Gossamer Bio, Inc. (GOSS)

Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations.

You should read the following discussion and analysis of our financial condition and results of operations together with our consolidated financial statements and related notes included elsewhere in this annual report. This discussion and analysis contains forward-looking statements based upon our current beliefs, plans and expectations that involve risks, uncertainties and assumptions. Our actual results may differ materially from those anticipated in these forward-looking statements as a result of various factors, including those set forth under “Risk Factors” or in other parts of this annual report.

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Overview

We are a clinical-stage biopharmaceutical company focused on the development and commercialization of seralutinib for the treatment of PH, including PAH and PH-ILD. Our goal is to be an industry leader in, and to enhance the lives of patients living with PH. In May 2024, we entered into the collaboration agreement for seralutinib with Chiesi. In December 2022, we announced positive topline results from the Phase 2 TORREY Study in PAH patients. In the fourth quarter of 2023, we initiated the registrational Phase 3 PROSERA Study in PAH. We expect to report topline data from the PROSERA study in the fourth quarter of 2025. In addition to PAH, we believe that seralutinib holds potential as a therapeutic for the treatment of PH-ILD. We expect to activate clinical sites for a global registrational Phase 3 for the treatment of PH-ILD in the second half of 2025. We have assembled a deeply experienced and highly skilled group of industry veterans, scientists, clinicians and key opinion leaders from leading biotechnology and pharmaceutical companies, as well as leading academic centers from around the world. Our employees are a team of highly dedicated, passionate individuals who pride themselves on a culture of respect, humility, transparency, inclusion, dedication, collaboration and fun. Our ultimate goal is to enhance and extend the lives of patients.

We were incorporated in October 2015 and commenced operations in 2017. To date, we have focused primarily on organizing and staffing our company, business planning, raising capital, identifying, acquiring and in-licensing our product candidates and conducting preclinical studies and clinical trials. We have funded our operations primarily through equity financings and the collaboration agreement. We raised $1,401.1 million from October 2017 through December 31, 2024 through the sale of Series A and Series B convertible preferred stock, issuance of convertible notes, proceeds from our IPO, completed in February 2019, proceeds from 2027 Notes (as defined below), issuance of common stock in May 2020 and July 2022, issuance of common stock and accompanying warrants in July 2023 and entry into the collaboration agreement in May 2024. As of December 31, 2024, we had $294.5 million in cash, cash equivalents and marketable securities.

We have incurred significant operating losses since our inception and expect to continue to incur significant operating losses for the foreseeable future. For the years ended December 31, 2024 and 2023, our net loss was $56.5 million and $179.8 million, respectively. As of December 31, 2024, we had an accumulated deficit of $1,268.6 million. We expect to incur expenses and operating losses for the foreseeable future as we continue our development of and seek regulatory approvals for seralutinib, including the conduct of ongoing and planned clinical trials and other research and development activities; and as we hire additional personnel, protect our intellectual property and incur additional costs associated with being a public company. In addition, as seralutinib progresses through development and toward commercialization, we will need to make milestone payments to Pulmokine from whom we have in-licensed seralutinib. Our net losses may fluctuate significantly from quarter-to-quarter and year-to-year, depending in particular on the timing of our clinical trials and preclinical studies and our expenditures on other research and development activities.

On May 3, 2024, we announced a strategic global partnership with Chiesi. Under the terms of the collaboration agreement, we granted Chiesi exclusive licenses for the worldwide development, manufacture and commercialization of seralutinib and licensed products and an Equity Option to purchase our common stock. The total potential transaction value includes the one-time $160.0 million development cost reimbursement payment for licenses, research and development funding, and certain regulatory and commercial milestones. We and Chiesi share equally in the costs of ongoing global seralutinib clinical development and the costs of commercialization in the United States, with the exception of the PROSERA Phase 3 study, for which we bear all costs. We are also eligible for double-digit royalties in the mid-to-high teens percentage on tiers of annual net sales outside of the U.S. and to an equal share of profits and losses from the commercialization of seralutinib and licensed products in the U.S. . For additional information regarding the collaboration agreement, as well as our license agreement with Pulmokine, see the section titled “Business—License and Collaboration Agreements” in this annual report.

We do not expect to generate any revenue from product sales unless and until we successfully complete development and obtain regulatory approval for seralutinib, which we expect will take a number of years. If we obtain regulatory approval for seralutinib, we expect to incur significant commercialization expenses related to product sales, marketing, manufacturing and distribution. Accordingly, until such time as we can generate substantial product revenues to support our cost structure, if ever, we expect to finance our cash needs through equity offerings, debt financings or other capital sources, including potentially collaborations, licenses and other similar arrangements. However, we may be unable to raise additional funds or enter into such other arrangements when needed on favorable terms or at all. Our failure to raise capital or enter into such other arrangements when needed could have a negative impact on our financial condition and on our ability to pursue our business plans and strategies. If we are unable to raise additional capital when needed, we could be forced to delay, limit, reduce or terminate seralutinib development or future commercialization efforts or grant additional rights to develop and market seralutinib even if we would otherwise prefer to retain such right.

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Components of Results of Operations

Revenue

To date, we have generated all of our revenue from our collaboration agreement with Chiesi. Our revenue consists of a one-time development cost reimbursement payment for licenses and ongoing cost-sharing payments for performance of research and development services classified as revenue from contracts with collaborators.

In the future, we may generate revenue from a combination of license fees and other upfront payments, other funded research and development agreements, milestone payments, product sales, other third-party funding, US profit/loss share and royalties in connection with strategic alliances. We expect that any revenue we generate will fluctuate from quarter-to-quarter as a result of the timing of performance of research and development services, the timing of our achievement of regulatory and commercialization milestones, the timing and amount of payments relating to such milestones and the extent to which any of our products are approved and successfully commercialized. If we are unable to fund our development costs or we are unable to develop product candidates in a timely manner or obtain regulatory approval for them, our ability to generate future revenues and our results of operations and financial position would be adversely affected.

Operating expenses

Research and development

Research and development expenses relate primarily to preclinical and clinical development of seralutinib, as well as our discontinued clinical product candidates. Research and development expenses are recognized as incurred and payments made prior to the receipt of goods or services to be used in research and development are capitalized until the goods or services are received.

Research and development expenses include or could include:

•salaries, payroll taxes, employee benefits, and stock-based compensation charges for those individuals involved in research and development efforts;

•external research and development expenses incurred under agreements with contract research organizations, or CROs, investigative sites and consultants to conduct our clinical trials and preclinical and non-clinical studies;

•laboratory supplies;

•costs related to manufacturing our product candidates for clinical trials and preclinical studies, including fees paid to third-party manufacturers;

•costs related to compliance with regulatory requirements; and

•facilities, depreciation and other allocated expenses, which include direct and allocated expenses for rent, maintenance of facilities, insurance, equipment and other supplies.

Our direct research and development expenses consist principally of external costs, such as fees paid to CROs, investigative sites and consultants in connection with our clinical trials, preclinical and non-clinical studies, and costs related to manufacturing clinical trial materials. We deploy our personnel and facility related resources across all of our research and development activities. We track external costs and personnel expense on a program-by-program basis and allocate common expenses, such as facility related resources, to each program based on the personnel resources allocated to such program. Stock-based compensation and personnel and common expenses not attributable to a specific program are considered unallocated research and development expenses. We categorize Terminated Programs as any research and development expenses attributable to our clinical stage product candidates that were terminated prior to December 31, 2023.

We expect to incur research and development expenses for the foreseeable future as we continue the development of seralutinib. We cannot determine with certainty the timing of initiation, the duration or the completion costs of current or future preclinical studies and clinical trials of seralutinib due to the inherently unpredictable nature of preclinical and clinical development. Clinical and preclinical development timelines, the probability of success and development costs can differ materially from expectations. We anticipate that we will make determinations as to how much funding to direct to seralutinib on an ongoing basis in response to the results of ongoing and future preclinical studies and clinical trials, regulatory

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developments and our ongoing assessments as to seralutinib's commercial potential. We will need to raise substantial additional capital in the future.

Our clinical development costs may vary significantly based on factors such as:

•per patient trial costs;

•the number of trials required for approval;

•the number of sites included in the trials;

•the countries in which the trials are conducted;

•the length of time required to enroll eligible patients;

•the number of patients that participate in the trials;

•the number of doses that patients receive;

•the drop-out or discontinuation rates of patients;

•potential additional safety monitoring requested by regulatory agencies;

•the duration of patient participation in the trials and follow-up;

•the cost and timing of manufacturing seralutinib;

•the costs incurred as a result of health epidemics and pandemics, including the COVID-19 pandemic, and clinical site staff shortages, including clinical trial delays;

•the phase 3 stage of development for seralutinib; and

•the efficacy and safety profile of seralutinib.

In process research and development

In process research and development, or IPR&D, expenses include IPR&D acquired as part of an asset acquisition or in-license for which there is no alternative future use, are expensed as incurred.

General and administrative

General and administrative expenses consist primarily of salaries and employee-related costs, including stock-based compensation, for personnel in executive, finance and other administrative functions. Other significant costs include facility-related costs, legal fees relating to intellectual property and corporate matters, professional fees for accounting and consulting services and insurance costs.

We expect to incur general and administrative expenses for the foreseeable future to support our current infrastructure and continued costs of operating as a public company. These expenses will likely include audit, legal, regulatory, and tax-related services associated with maintaining compliance with exchange listing and SEC requirements, director and officer insurance premiums, and investor relations costs associated with operating as a public company.

Other income (expense), net

Other income (expense), net consists of (1) interest income on our cash, cash equivalents and marketable securities, (2) investment accretion, (3) interest expense related to our Credit Facility, prior to its termination and the 2027 Notes, (4) research and development tax credit and (5) other miscellaneous income (expense).

Provision for income taxes

Our tax provision from income taxes is determined using an estimate of our annual effective tax rate, adjusted for discrete items, if any, that are taken into account in the relevant period.

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Critical Accounting Policies and Estimates

Our management’s discussion and analysis of our financial condition and results of operations are based on our consolidated financial statements, which have been prepared in accordance with generally accepted accounting principles in the United States, or GAAP. The preparation of these financial statements requires us to make judgments and estimates that affect the reported amounts of assets, liabilities, revenue, expenses and the disclosure of contingent assets and liabilities in our consolidated financial statements. We base our estimates on historical experience, known trends and events, and various other factors that are believed to be reasonable under the circumstances. Actual results may differ from these estimates under different assumptions or conditions (See Note 2 to our consolidated financial statements).

Accrued expenses

As part of the process of preparing our consolidated financial statements, we are required to estimate our accrued expenses as of each balance sheet date. This process involves reviewing open contracts and purchase orders, communicating with our personnel to identify services that have been performed on our behalf and estimating the level of service performed and the associated cost incurred for the service when we have not yet been invoiced or otherwise notified of the actual cost. We make estimates of our accrued expenses as of each balance sheet date based on facts and circumstances known to us at that time. We periodically confirm the accuracy of our estimates with the service providers and make adjustments if necessary. The significant estimates in our accrued research and development expenses include the costs incurred for services performed by our vendors in connection with research and development activities for which we have not yet been invoiced.

We base our expenses related to research and development activities on our estimates of the services received and efforts expended pursuant to quotes and contracts with vendors that conduct research and development on our behalf. The financial terms of these agreements are subject to negotiation, vary from contract to contract and may result in uneven payment flows. There may be instances in which payments made to our vendors will exceed the level of services provided and result in a prepayment of the research and development expense. In accruing service fees, we estimate the time period over which services will be performed and the level of effort to be expended in each period. If the actual timing of the performance of services or the level of effort varies from our estimate, we adjust the accrual or prepaid expense accordingly. Advance payments for goods and services that will be used in future research and development activities are expensed when the activity has been performed or when the goods have been received rather than when the payment is made.

Although we do not expect our estimates to be materially different from amounts actually incurred, if our estimates of the status and timing of services performed differ from the actual status and timing of services performed, it could result in us reporting amounts that are too high or too low in any particular period. To date, there have been no material differences between our estimates of such expenses and the amounts actually incurred.

Collaborative Arrangements

We assess whether our licensing and other agreements are collaborative arrangements based on whether they involve joint operating activities and whether both parties have active participation in the arrangement and are exposed to significant risks and rewards. For arrangements that we determine are collaborations, we identify each unit of account, and then determine whether a customer relationship exists for that unit of account. If we determine a performance obligation within the collaborative arrangement to be with a customer, we apply our revenue recognition accounting policy. If a portion of a distinct bundle of goods or services within the collaborative arrangement is not with a customer, we apply recognition and measurement based on an analogy to authoritative accounting literature or, if there is no appropriate analogy, a reasonable, rational and consistently applied accounting policy election. To the extent the arrangement is within the scope of Accounting Standards Codification, or ASC, Topic 808, we assess whether aspects of the arrangement between us and the collaboration partner are within the scope of other accounting literature. If we conclude that some or all aspects of the arrangement represent a transaction with a customer, we account for those aspects of the arrangement within the scope of ASC Topic 606, Revenue from Contracts with Customers (ASC 606).

Revenue Recognition

We recognize revenue in accordance with ASC 606, Revenue from Contracts with Customers, or Topic 606, which applies to all contracts with customers, except for contracts that are within the scope of other standards, such as leases, insurance, collaboration arrangements and financial instruments. Under Topic 606, we recognize revenue when our customer obtains control of promised goods or services, in an amount that reflects the consideration that the entity expects to receive in exchange for those goods or services. To determine revenue recognition for contracts with customers, we perform the following five steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine

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the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the entity satisfies a performance obligation. We only apply the five-step model to contracts when it is probable that we will collect the consideration we are entitled to in exchange for the goods or services we transfer. At contract inception, once the contract is determined to be within the scope of Topic 606, we assess the goods or services promised within each contract, determine those that are performance obligations, and assess whether each promised good or service is distinct. We then recognize as revenue the amount of the transaction price, reduced by a consideration payable to a customer, that is allocated to the respective performance obligation when (or as) the performance obligation is satisfied. We utilize key assumptions to determine a stand-alone selling price for performance obligations, which may include forecasted revenues or costs, expected development timelines, discount rates and probabilities of technical and regulatory success.

Results of Operations for the Years Ended December 31, 2024 and 2023

The following table sets forth our selected statements of operations data for the years ended December 31, 2024 and 2023:

Operating Expenses

Revenue

For the year ended December 31, 2024, our revenue was $114.7 million. Our revenue is generated from our ongoing collaboration with Chiesi and consists of a one-time development cost reimbursement payment for the licenses and ongoing cost-sharing payments for performance of research and development and pre-commercial services.

Research and development expenses

Research and development expenses were $138.5 million for the year ended December 31, 2024, compared to $135.3 million for the year ended December 31, 2023, for an increase of $3.2 million, which was primarily attributable to an increase of $36.1 million of costs associated with clinical trials for seralutinib, offset by a decrease of $32.9 million of costs associated with preclinical studies and clinical trials for terminated programs.

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The following table shows our research and development expenses by program for the years ended December 31, 2024 and 2023:

In process research and development expenses

There were no IPR&D expenses for the year ended December 31, 2024. IPR&D expenses for the year ended December 31, 2023 were $10.0 million, which was attributable to a milestone obligation incurred upon the initiation of the Phase 3 clinical trial of seralutinib in the fourth quarter of 2023 and paid to Pulmokine in 2024.

General and administrative expenses

General and administrative expenses were $36.1 million for the year ended December 31, 2024, compared to $38.5 million for the year ended December 31, 2023, for a decrease of $2.3 million, which was primarily attributable to a $2.2 million decrease in stock-based compensation expense, a decrease of $0.8 million in legal expense, a decrease of $0.6 million in insurance costs, offset by an increase of $0.6 million in professional services expense and an increase of $0.4 million in travel costs.

Other income (expense), net

Other income, net was $4.3 million for the year ended December 31, 2024, compared to other income, net of $3.9 million for the year ended December 31, 2023, for an increase of $0.3 million, which was primarily attributable to a $3.2 million increase in investment accretion and a $2.0 million decrease in interest expense, offset by a $3.6 million decrease in other income primarily related to $2.8 million of employee retention credit under the CARES Act and $1.0 million of Ireland Corporate R&D tax credit.

Provision for income taxes

For the year ended December 31, 2024, the tax expense was $0.9 million, which was primarily attributable to the treatment of the Chiesi income and a partial release of the valuation allowance. There was no provision for income taxes for the year ended December 31, 2023.

Results of Operations for the Years Ended December 31, 2023 and 2022

The discussion of our financial condition and results of operations for the year ended December 31, 2023 and the comparison of 2023 and 2022 results included in Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations in our Annual Report on Form 10-K for the year ended December 31, 2023 is incorporated by reference into this MD&A.

Liquidity and Capital Resources

We have incurred substantial operating losses since our inception and expect to continue to incur significant operating losses for the foreseeable future and may never become profitable. As of December 31, 2024 and 2023, we had an accumulated deficit of $1,268.6 million and $1,212.0 million, respectively.

Our primary use of cash is to fund operating expenses, which consist primarily of research and development expenditures, and to a lesser extent, general and administrative expenditures. Cash used to fund operating expenses is impacted by the timing of when we pay these expenses, as reflected in the change in our outstanding accounts payable and accrued expenses. We may also use cash on hand to repurchase 2027 Notes through open-market transactions, including through a Rule 10b5-1 trading plan to facilitate open-market repurchases, or otherwise, from time to time.

Under our license agreement with Pulmokine, we have payment obligations that are contingent upon future events such as our achievement of specified development, regulatory and commercial milestones and are required to make royalty payments in connection with the sale of products developed under the agreement. As of December 31, 2024, we were

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unable to estimate the timing or likelihood of achieving the milestones or making future product sales. Other contractual obligations include future payments under the 2027 Notes and existing operating leases.

From our inception through the year ended December 31, 2024, our operations have been financed primarily by proceeds of $1,401.1 million from the sale of Series A and Series B convertible preferred stock, proceeds from our IPO, proceeds from the 2027 Notes, proceeds from issuance of common stock in May 2020 and July 2022, proceeds from issuance of common stock and accompanying warrants in July 2023 and the collaboration agreement with Chiesi. As of December 31, 2024, we had cash, cash equivalents and marketable securities of $294.5 million. Cash in excess of immediate requirements is invested in accordance with our investment policy, primarily with a view to capital preservation and liquidity.

On April 10, 2020, we filed a registration statement on Form S-3, or the 2020 Shelf Registration Statement, covering the offering from time to time of common stock, preferred stock, debt securities, warrants and units, which registration statement became automatically effective on April 10, 2020.

On May 21, 2020, we issued $200.0 million aggregate principal amount 5.00% convertible senior notes due 2027 in a registered public offering, or the 2027 Notes. The interest rate on the 2027 Notes is fixed at 5.00% per annum. Interest is payable semi-annually in arrears on June 1 and December 1 of each year commencing on December 1, 2020. The total net proceeds from the 2027 Notes, after deducting the underwriting discounts and commissions and other offering costs, were approximately $193.6 million. Concurrent with the registered underwritten public offering of the 2027 Notes, we completed an underwritten public offering of 9,433,963 shares of our common stock. We received net proceeds of $117.1 million, after deducting underwriting discounts and commissions and other offering costs. Our concurrent offerings of 2027 Notes and common stock were registered pursuant to the 2020 Shelf Registration Statement.

On July 15, 2022, we completed a private placement of 16,649,365 shares of our common stock. The aggregate gross proceeds for the private placement were approximately $120.1 million, before deducting offering expenses. On August 9, 2022, we filed a registration statement on Form S-3 registering the resale of the shares of common stock issued in the private placement, which became automatically effective on August 9, 2022.

On July 24, 2023, we completed a private placement of 129,869,440 shares of our common stock and 32,467,360 accompanying warrants. The aggregate gross proceeds for the private placement were $212.1 million, before deducting offering expenses. On August 18, 2023, we filed a registration statement on Form S-3 registering the resale of the shares of common stock and shares of common stock issuable upon the exercise of warrants issued in the private placement, which was declared effective on August 28, 2023.

On May 3, 2024, we entered into the collaboration agreement with Chiesi. In consideration and as reimbursement for our development costs, Chiesi paid us an up-front, nonrefundable payment of $160.0 million. In addition, we and Chiesi share equally in the costs of ongoing global seralutinib clinical development, with the exception of the PROSERA Phase 3 study, and the costs of commercialization in the United States. For the year ended on December 31, 2024, we received cost-sharing payments from Chiesi in the amount of $7.8 million.

Additional information about our long-term borrowings is presented in Note 5 “Indebtedness” and operating leases is presented in Note 11 "Commitments and Contingencies" to the Notes to Consolidated Financial Statements included in Part II, Item 8, of this Form 10-K, herein by this reference.

The following table shows a summary of our cash flows for each of the years shown below:

Operating activities

During the year ended December 31, 2024, operating activities used approximately $3.5 million of cash, primarily resulting from a net loss of $56.5 million and changes in amortization of premium on investments, net of accretion of

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discount, of $13.1 million, reduced by stock-based compensation expense of $20.6 million and changes in contract liabilities of $55.9 million.

During the year ended December 31, 2023, operating activities used approximately $159.2 million of cash, primarily resulting from a net loss of $179.8 million and changes in accrued research and development expenses of $7.8 million, changes in amortization of premium on investments of $9.5 million, reduced by stock-based compensation expense of $28.5 million and in process research and development expense of $10.0 million.

During the year ended December 31, 2022, operating activities used approximately $187.0 million of cash, primarily resulting from a net loss of $229.4 million and payments against operating lease liabilities of $2.7 million, partially reduced by stock-based compensation expense of $42.6 million and amortization of operating lease right-of-use assets of $2.6 million.

Investing activities

During the year ended December 31, 2024, investing activities provided approximately $29.0 million of cash, primarily resulting from the maturities of marketable securities of $523.8 million, offset by purchases of marketable securities of $494.8 million.

During the year ended December 31, 2023, investing activities used approximately $111.0 million of cash, primarily resulting from the purchases of marketable securities of $441.7 million, offset by the maturities of marketable securities of $330.7 million.

During the year ended December 31, 2022, investing activities used approximately $1.0 million of cash, primarily resulting from the purchase of marketable securities of $238.0 million and the purchase of property and equipment of $0.4 million, partially offset by maturities of marketable securities of $237.5 million.

Financing activities

During the year ended December 31, 2024, financing activities used $11.5 million of cash, resulting from the principal repayment of long-term debt of $12.6 million, reduced by the proceeds from the issuance of equity option pursuant to stock purchase agreement with Chiesi of $0.5 million and the proceeds from issuance of common stock pursuant to the ESPP of $0.6 million.

During the year ended December 31, 2023, financing activities provided $190.2 million of cash, primarily resulting from proceeds from the issuance of common stock and warrants in a private offering of $201.3 million, reduced by the principal repayments of long-term debt of $11.6 million.

During the year ended December 31, 2022, financing activities provided $117.1 million of cash, primarily resulting from proceeds from the purchase of shares pursuant to our 2019 Employee Stock Purchase Plan, or ESPP, of $1.2 million, proceeds from the private offering of $119.9 million, and proceeds from the exercise of stock options of $1.7 million, partially offset by the principal repayments of long-term debt of $5.8 million.

Funding requirements

Based on our current operating plan, we believe that our existing cash, cash equivalents and marketable securities, will be sufficient to fund our operations through at least the next 12 months from the date these consolidated financial statements were available to be issued. However, our forecast of the period of time through which our financial resources will be adequate to support our operations is a forward-looking statement that involves risks and uncertainties, and actual results could vary materially. We have based this estimate on assumptions that may prove to be wrong, and we could use our capital resources sooner than we expect. Additionally, the process of testing seralutinib in clinical trials is costly, and the timing of progress and expenses in these trials is uncertain.

Our future capital requirements will depend on many factors, including:

•the type, number, scope, progress, enrollment pace, expansions, results, costs and timing of, our preclinical studies and clinical trials of seralutinib which we are pursuing or may choose to pursue in the future;

•the costs and timing of manufacturing for seralutinib;

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•the costs, timing and outcome of regulatory review of seralutinib;

•the costs of obtaining, maintaining and enforcing our patents and other intellectual property rights;

•our efforts to enhance operational systems and hire additional personnel to satisfy our obligations as a public company, including enhanced internal controls over financial reporting;

•the costs associated with hiring additional personnel and consultants to continue the development and potential commercialization of seralutinib;

•the timing and amount of the milestone or other payments we must make to Pulmokine from whom we have in-licensed seralutinib;

•the costs and timing of establishing or securing sales and marketing capabilities if seralutinib is approved;

•our ability to achieve sufficient market acceptance, coverage and adequate reimbursement from third-party payors and adequate market share and revenue for any approved products;

•the terms and timing of establishing and maintaining collaborations, licenses and other similar arrangements;

•costs associated with any products or technologies that we may in-license or acquire; and

•any delays and cost increases that result from epidemic diseases.

Until such time as we can generate substantial product revenues to support our cost structure, if ever, we expect to finance our cash needs through equity offerings, debt financings or other capital sources, including potentially collaborations, licenses and other similar arrangements.

However, we may be unable to raise additional funds or enter into such other arrangements when needed on favorable terms or at all. To the extent that we raise additional capital through the sale of equity or convertible debt securities, the ownership interest of our stockholders will be or could be diluted, and the terms of these securities may include liquidation or other preferences that adversely affect the rights of our common stockholders. Debt financing and preferred equity financing, if available, may involve agreements that include covenants limiting or restricting our ability to take specific actions, such as incurring additional debt, making capital expenditures or declaring dividends. If we raise funds through collaborations, licenses and other similar arrangements with third parties, we may have to relinquish valuable rights to our technologies, future revenue streams, research programs or product candidates or grant licenses on terms that may not be favorable to us and/or may reduce the value of our common stock. Our failure to raise capital or enter into such other arrangements when needed could have a negative impact on our financial condition and on our ability to pursue our business plans and strategies. If we are unable to raise additional capital when needed, we could be forced to delay, limit, reduce or terminate seralutinib development or future commercialization efforts or grant rights to develop and market seralutinib even if we would otherwise prefer to develop and market seralutinib ourselves.

Recent Accounting Pronouncements

See Note 2 to our consolidated financial statements included elsewhere in this annual report.

Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations.

You should read the following discussion and analysis of our financial condition and results of operations together with our consolidated financial statements and related notes included elsewhere in this annual report. This discussion and analysis contains forward-looking statements based upon our current beliefs, plans and expectations that involve risks, uncertainties and assumptions. Our actual results may differ materially from those anticipated in these forward-looking statements as a result of various factors, including those set forth under “Risk Factors” or in other parts of this annual report.

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Overview

We are a clinical-stage biopharmaceutical company focused on the development and commercialization of seralutinib for the treatment of PAH. Our goal is to be an industry leader in, and to enhance the lives of patients living with PH. In December 2022, we announced positive topline results from the Phase 2 TORREY Study in PAH patients. In the fourth quarter of 2023, we initiated the registrational Phase 3 PROSERA Study in PAH. We expect to report topline data from the PROSERA study in the fourth quarter of 2025. In addition to PAH, we believe that seralutinib holds potential as a therapeutic for the treatment of PH-ILD. We are actively pursuing clinical development plans for seralutinib in PH-ILD. We have assembled a deeply experienced and highly skilled group of industry veterans, scientists, clinicians and key opinion leaders from leading biotechnology and pharmaceutical companies, as well as leading academic centers from around the world. Our employees are a team of highly dedicated, passionate individuals who pride themselves on a culture of respect, humility, transparency, inclusion, dedication, collaboration and fun. Our ultimate goal is to enhance and extend the lives of patients.

We were incorporated in October 2015 and commenced operations in 2017. To date, we have focused primarily on organizing and staffing our company, business planning, raising capital, identifying, acquiring and in-licensing our product candidates and conducting preclinical studies and clinical trials. We have funded our operations primarily through equity and debt financings. We raised $1,263.2 million from October 2017 through December 31, 2023 through the sale of Series A and Series B convertible preferred stock, issuance of convertible notes, proceeds from our initial public offering, or IPO, completed in February 2019, proceeds from the Credit Facility and 2027 Notes (as defined below), issuance of common stock in May 2020 and July 2022 and issuance of common stock and accompanying warrants in July 2023. As of December 31, 2023, we had $296.4 million in cash, cash equivalents and marketable securities.

We have incurred significant operating losses since our inception and expect to continue to incur significant operating losses for the foreseeable future. For the years ended December 31, 2023 and 2022, our net loss was $179.8 million and $229.4 million, respectively. As of December 31, 2023, we had an accumulated deficit of $1,212.0 million. We expect our expenses and operating losses will remain relatively flat as compared to 2023, as we continue our development of and seek regulatory approvals for seralutinib, including the conduct of ongoing and planned clinical trials and other research and development activities; and as we hire additional personnel, protect our intellectual property and incur additional costs associated with being a public company. In addition, as seralutinib progresses through development and toward commercialization, we will need to make milestone payments to Pulmokine from whom we have in-licensed seralutinib. Our net losses may fluctuate significantly from quarter-to-quarter and year-to-year, depending in particular on the timing of our clinical trials and preclinical studies and our expenditures on other research and development activities.

We do not expect to generate any revenue from product sales unless and until we successfully complete development and obtain regulatory approval for seralutinib, which we expect will take a number of years. If we obtain regulatory approval for seralutinib, we expect to incur significant commercialization expenses related to product sales, marketing, manufacturing and distribution. Accordingly, until such time as we can generate substantial product revenues to support our cost structure, if ever, we expect to finance our cash needs through equity offerings, debt financings or other capital sources, including potentially collaborations, licenses and other similar arrangements. However, we may be unable to raise additional funds or enter into such other arrangements when needed on favorable terms or at all. Our failure to raise capital or enter into such other arrangements when needed could have a negative impact on our financial condition and on our ability to pursue our business plans and strategies. If we are unable to raise additional capital when needed, we could be forced to delay, limit, reduce or terminate seralutinib development or future commercialization efforts or grant rights to develop and market seralutinib even if we would otherwise prefer to develop and market seralutinib ourselves.

Components of Results of Operations

Revenue

We have not generated any revenue since our inception and do not expect to generate any revenue from the sale of products for the foreseeable future.

Operating expenses

Research and development

Research and development expenses relate primarily to preclinical and clinical development of seralutinib and discovery efforts, as well as our discontinued clinical product candidates. Research and development expenses are recognized as incurred and payments made prior to the receipt of goods or services to be used in research and development are capitalized until the goods or services are received.

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Research and development expenses include or could include:

•salaries, payroll taxes, employee benefits, and stock-based compensation charges for those individuals involved in research and development efforts;

•external research and development expenses incurred under agreements with contract research organizations, or CROs, investigative sites and consultants to conduct our clinical trials and preclinical and non-clinical studies;

•laboratory supplies;

•costs related to manufacturing our product candidates for clinical trials and preclinical studies, including fees paid to third-party manufacturers;

•costs related to compliance with regulatory requirements; and

•facilities, depreciation and other allocated expenses, which include direct and allocated expenses for rent, maintenance of facilities, insurance, equipment and other supplies.

Our direct research and development expenses consist principally of external costs, such as fees paid to CROs, investigative sites and consultants in connection with our clinical trials, preclinical and non-clinical studies, and costs related to manufacturing clinical trial materials. We deploy our personnel and facility related resources across all of our research and development activities. We track external costs and personnel expense on a program-by-program basis and allocate common expenses, such as facility related resources, to each program based on the personnel resources allocated to such program. Stock-based compensation and personnel and common expenses not attributable to a specific program are considered unallocated research and development expenses. We categorize Terminated Programs as any research and development expenses attributable to our clinical stage product candidates that were terminated prior to December 31, 2023.

We expect our research and development expenses for the foreseeable future to remain relatively flat as we continue the development of seralutinib. We cannot determine with certainty the timing of initiation, the duration or the completion costs of current or future preclinical studies and clinical trials of seralutinib due to the inherently unpredictable nature of preclinical and clinical development. Clinical and preclinical development timelines, the probability of success and development costs can differ materially from expectations. We anticipate that we will make determinations as to how much funding to direct to seralutinib on an ongoing basis in response to the results of ongoing and future preclinical studies and clinical trials, regulatory developments and our ongoing assessments as to seralutinib's commercial potential. We will need to raise substantial additional capital in the future.

Our clinical development costs may vary significantly based on factors such as:

•per patient trial costs;

•the number of trials required for approval;

•the number of sites included in the trials;

•the countries in which the trials are conducted;

•the length of time required to enroll eligible patients;

•the number of patients that participate in the trials;

•the number of doses that patients receive;

•the drop-out or discontinuation rates of patients;

•potential additional safety monitoring requested by regulatory agencies;

•the duration of patient participation in the trials and follow-up;

•the cost and timing of manufacturing seralutinib;

•the costs incurred as a result of the COVID-19 pandemic, including clinical trial delays;

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•the phase 3 stage of development for seralutinib; and

•the efficacy and safety profile of seralutinib.

In process research and development

In process research and development, or IPR&D, expenses include IPR&D acquired as part of an asset acquisition or in-license for which there is no alternative future use, are expensed as incurred.

General and administrative

General and administrative expenses consist primarily of salaries and employee-related costs, including stock-based compensation, for personnel in executive, finance and other administrative functions. Other significant costs include facility-related costs, legal fees relating to intellectual property and corporate matters, professional fees for accounting and consulting services and insurance costs.

We expect our general and administrative expenses for the foreseeable future to remain relatively flat to support our current infrastructure and continued costs of operating as a public company. These expenses will likely include audit, legal, regulatory, and tax-related services associated with maintaining compliance with exchange listing and SEC requirements, director and officer insurance premiums, and investor relations costs associated with operating as a public company.

Other income (expense), net

Other income (expense), net consists of (1) interest income on our cash, cash equivalents and marketable securities, (2) investment accretion, (3) sublease income, (4) interest expense related to our Credit Facility and our 2027 Notes, (5) employee retention credit under the Coronavirus Aid, Relief, and Economic Security Act, or the CARES Act, (6) Ireland Corporate R&D tax credit and (7) other miscellaneous income (expense).

Critical Accounting Policies and Estimates

Our management’s discussion and analysis of our financial condition and results of operations are based on our consolidated financial statements, which have been prepared in accordance with generally accepted accounting principles in the United States, or GAAP. The preparation of these financial statements requires us to make judgments and estimates that affect the reported amounts of assets, liabilities, and expenses and the disclosure of contingent assets and liabilities in our consolidated financial statements. We base our estimates on historical experience, known trends and events, and various other factors that are believed to be reasonable under the circumstances. Actual results may differ from these estimates under different assumptions or conditions (See Note 2 to our consolidated financial statements).

Accrued expenses

As part of the process of preparing our consolidated financial statements, we are required to estimate our accrued expenses as of each balance sheet date. This process involves reviewing open contracts and purchase orders, communicating with our personnel to identify services that have been performed on our behalf and estimating the level of service performed and the associated cost incurred for the service when we have not yet been invoiced or otherwise notified of the actual cost. We make estimates of our accrued expenses as of each balance sheet date based on facts and circumstances known to us at that time. We periodically confirm the accuracy of our estimates with the service providers and make adjustments if necessary. The significant estimates in our accrued research and development expenses include the costs incurred for services performed by our vendors in connection with research and development activities for which we have not yet been invoiced.

We base our expenses related to research and development activities on our estimates of the services received and efforts expended pursuant to quotes and contracts with vendors that conduct research and development on our behalf. The financial terms of these agreements are subject to negotiation, vary from contract to contract and may result in uneven payment flows. There may be instances in which payments made to our vendors will exceed the level of services provided and result in a prepayment of the research and development expense. In accruing service fees, we estimate the time period over which services will be performed and the level of effort to be expended in each period. If the actual timing of the performance of services or the level of effort varies from our estimate, we adjust the accrual or prepaid expense accordingly. Advance payments for goods and services that will be used in future research and development activities are expensed when the activity has been performed or when the goods have been received rather than when the payment is made.

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Although we do not expect our estimates to be materially different from amounts actually incurred, if our estimates of the status and timing of services performed differ from the actual status and timing of services performed, it could result in us reporting amounts that are too high or too low in any particular period. To date, there have been no material differences between our estimates of such expenses and the amounts actually incurred.

Results of Operations for the Years Ended December 31, 2023 and 2022

The following table sets forth our selected statements of operations data for the years ended December 31, 2023 and 2022:

Operating Expenses

Research and development

Research and development expenses were $135.3 million for the year ended December 31, 2023, compared to $170.9 million for the year ended December 31, 2022, for a decrease of $35.6 million, which was primarily attributable to a decrease of $65.8 million of costs associated with preclinical studies and clinical trials for terminated programs, offset by an increase of $30.2 million of costs associated with preclinical studies and clinical trials for seralutinib.

The following table shows our research and development expenses by program for the years ended December 31, 2023 and 2022:

In process research and development

IPR&D expenses for the year ended December 31, 2023 were $10.0 million, which was attributable to a milestone obligation incurred upon the initiation of the Phase 3 clinical trial of seralutinib in the fourth quarter of 2023 and paid to Pulmokine in 2024. There were no significant IPR&D expenses for the year ended December 31, 2022.

General and administrative

General and administrative expenses were $38.5 million for the year ended December 31, 2023, compared to $47.6 million for the year ended December 31, 2022, for a decrease of $9.2 million, which was primarily attributable to a $5.5 million decrease in stock-based compensation expense, a decrease of $1.3 million in professional services expense, a decrease of $0.7 million in insurance costs and a decrease of $0.9 million in other operating expense.

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Other income (expense), net

Other income, net was $3.9 million for the year ended December 31, 2023, compared to other expense, net of $10.8 million for the year ended December 31, 2022, for an increase of $14.7 million, which was primarily attributable to a $8.7 million increase in investment accretion, a $5.2 million increase in other income related to $2.8 million of employee retention credit under the CARES Act and $2.1 million of Ireland Corporate R&D tax credit, a $0.4 million increase in interest income and a $0.4 million decrease in interest expense.

Results of Operations for the Years Ended December 31, 2022 and 2021

The discussion of our financial condition and results of operations for the year ended December 31, 2022 and the comparison of 2022 and 2021 results included in Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations in our Annual Report on Form 10-K for the year ended December 31, 2022 is incorporated by reference into this MD&A.

Liquidity and Capital Resources

We have incurred substantial operating losses since our inception and expect to continue to incur significant operating losses for the foreseeable future and may never become profitable. As of December 31, 2023 and 2022, we had an accumulated deficit of $1,212.0 million and $1,032.2 million, respectively.

Our primary use of cash is to fund operating expenses, which consist primarily of research and development expenditures, and to a lesser extent, general and administrative expenditures. Cash used to fund operating expenses is impacted by the timing of when we pay these expenses, as reflected in the change in our outstanding accounts payable and accrued expenses. We may also use cash on hand to repurchase 2027 Notes through open-market transactions, including through a Rule 10b5-1 trading plan to facilitate open-market repurchases, or otherwise, from time to time.

Under our license agreement with Pulmokine, we have payment obligations that are contingent upon future events such as our achievement of specified development, regulatory and commercial milestones and are required to make royalty payments in connection with the sale of products developed under the agreement. As of December 31, 2023, we were unable to estimate the timing or likelihood of achieving the milestones or making future product sales. Other contractual obligations include future payments under our Credit Facility, 2027 Notes and existing operating leases.

From our inception through the year ended December 31, 2023, our operations have been financed primarily by proceeds of $1,263.2 million from the sale of Series A and Series B convertible preferred stock, proceeds from our IPO, proceeds from our Credit Facility and 2027 Notes, proceeds from issuance of common stock in May 2020 and July 2022 and proceeds from issuance of common stock and accompanying warrants in July 2023. As of December 31, 2023, we had cash, cash equivalents and marketable securities of $296.4 million. Cash in excess of immediate requirements is invested in accordance with our investment policy, primarily with a view to capital preservation and liquidity.

On May 2, 2019, we entered into a credit, guaranty and security agreement, as amended on September 18, 2019, July 2, 2020, December 7, 2022 and February 14, 2023, pursuant to which the lenders party thereto agreed to make term loans available to us for working capital and general business purposes, in a principal amount of up to $150.0 million in term loan commitments, including a $30.0 million term loan which was funded at the closing date, with the ability to access the remaining $120.0 million in two additional tranches (each $60.0 million), subject to specified availability periods, the achievement of certain clinical development milestones, minimum cash requirements and other customary conditions, or the Credit Facility. As of December 31, 2023, no tranches under the Credit Facility were available to be drawn.

On April 10, 2020, we filed a registration statement on Form S-3, or the 2020 Shelf Registration Statement, covering the offering from time to time of common stock, preferred stock, debt securities, warrants and units, which registration statement became automatically effective on April 10, 2020.

On May 21, 2020, we issued $200.0 million aggregate principal amount 5.00% convertible senior notes due 2027 in a registered public offering, or the 2027 Notes. The interest rate on the 2027 Notes is fixed at 5.00% per annum. Interest is payable semi-annually in arrears on June 1 and December 1 of each year commencing on December 1, 2020. The total net proceeds from the 2027 Notes, after deducting the underwriting discounts and commissions and other offering costs, were approximately $193.6 million. Concurrent with the registered underwritten public offering of the 2027 Notes, we completed an underwritten public offering of 9,433,963 shares of our common stock. We received net proceeds of $117.1 million, after deducting underwriting discounts and commissions and other offering costs. Our concurrent offerings of 2027 Notes and common stock were registered pursuant to the 2020 Shelf Registration Statement.

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On July 15, 2022, we completed a private placement of 16,649,365 shares of our common stock. The aggregate gross proceeds for the private placement were approximately $120.1 million, before deducting offering expenses. On August 9, 2022, we filed a registration statement on Form S-3 registering the resale of the shares of common stock issued in the private placement, which became automatically effective on August 9, 2022.

On July 24, 2023, we completed a private placement of 129,869,440 shares of our common stock and 32,467,360 accompanying warrants. The aggregate gross proceeds for the private placement were $212.1 million, before deducting offering expenses. On August 18, 2023, we filed a registration statement on Form S-3 registering the resale of the shares of common stock and shares of common stock issuable upon the exercise of warrants issued in the private placement, which was declared effective on August 28, 2023.

Additional information about our long-term borrowings is presented in Note 5 “Indebtedness” to the Notes to Consolidated Financial Statements included in Part II, Item 8, of this Form 10-K, herein by this reference.

The following table shows a summary of our cash flows for each of the years shown below:

Operating activities

During the year ended December 31, 2023, operating activities used approximately $159.2 million of cash, primarily resulting from a net loss of $179.8 million and changes in accrued research and development expenses of $7.8 million, changes in amortization of premium on investments of $9.5 million, reduced by stock-based compensation expense of $28.5 million and in process research and development expense of $10.0 million.

During the year ended December 31, 2022, operating activities used approximately $187.0 million of cash, primarily resulting from a net loss of $229.4 million and payments against operating lease liabilities of $2.7 million, partially reduced by stock-based compensation expense of $42.6 million and amortization of operating lease right-of-use assets of $2.6 million.

During the year ended December 31, 2021, operating activities used approximately $188.9 million of cash, primarily resulting from a net loss of $234.0 million, partially reduced by stock-based compensation expense of $32.0 million, amortization of long-term debt discount and issuance costs of $6.7 million and accrued research and development expenses of $5.8 million.

Investing activities

During the year ended December 31, 2023, investing activities used approximately $111.0 million of cash, primarily resulting from the purchases of marketable securities of $441.7 million, offset by the maturities of marketable securities of $330.7 million.

During the year ended December 31, 2022, investing activities used approximately $1.0 million of cash, primarily resulting from the purchase of marketable securities of $238.0 million and the purchase of property and equipment of $0.4 million, partially offset by maturities of marketable securities of $237.5 million.

During the year ended December 31, 2021, investing activities used approximately $117.4 million of cash, primarily resulting from the purchase of marketable securities of $152.0 million, partially offset by maturities of marketable securities of $36.2 million.

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Financing activities

During the year ended December 31, 2023, financing activities provided $190.2 million of cash, resulting from proceeds from the issuance of common stock and warrants in a private offering of $201.3 million, reduced by the principal repayments of long-term debt of $11.6 million.

During the year ended December 31, 2022, financing activities provided $117.1 million of cash, resulting from proceeds from the private offering of $119.9 million, proceeds from the exercise of stock options of $1.7 million, and from proceeds from the purchase of shares pursuant to our 2019 Employee Stock Purchase Plan, or ESPP, of $1.2 million, partially offset by the principal repayments of long-term debt of $5.8 million.

During the year ended December 31, 2021, financing activities provided $3.3 million of cash, resulting from proceeds from the exercise of stock options of $2.0 million, and from the purchase of shares pursuant to the ESPP of $1.3 million.

Funding requirements

Based on our current operating plan, we believe that our existing cash, cash equivalents and marketable securities, will be sufficient to fund our operations through at least the next 12 months from the date these consolidated financial statements were available to be issued. However, our forecast of the period of time through which our financial resources will be adequate to support our operations is a forward-looking statement that involves risks and uncertainties, and actual results could vary materially. We have based this estimate on assumptions that may prove to be wrong, and we could use our capital resources sooner than we expect. Additionally, the process of testing seralutinib in clinical trials is costly, and the timing of progress and expenses in these trials is uncertain.

Our future capital requirements will depend on many factors, including:

•the type, number, scope, progress, enrollment pace, expansions, results, costs and timing of, our preclinical studies and clinical trials of seralutinib which we are pursuing or may choose to pursue in the future;

•the costs and timing of manufacturing for seralutinib;

•the costs, timing and outcome of regulatory review of seralutinib;

•the costs of obtaining, maintaining and enforcing our patents and other intellectual property rights;

•our efforts to enhance operational systems and hire additional personnel to satisfy our obligations as a public company, including enhanced internal controls over financial reporting;

•the costs associated with hiring additional personnel and consultants to continue the development and potential commercialization of seralutinib;

•the timing and amount of the milestone or other payments we must make to Pulmokine from whom we have in-licensed seralutinib;

•the costs and timing of establishing or securing sales and marketing capabilities if seralutinib is approved;

•our ability to achieve sufficient market acceptance, coverage and adequate reimbursement from third-party payors and adequate market share and revenue for any approved products;

•the terms and timing of establishing and maintaining collaborations, licenses and other similar arrangements;

•costs associated with any products or technologies that we may in-license or acquire; and

•any delays and cost increases that result from the COVID-19 pandemic or other epidemic diseases.

Until such time as we can generate substantial product revenues to support our cost structure, if ever, we expect to finance our cash needs through equity offerings, our Credit Facility, debt financings or other capital sources, including potentially collaborations, licenses and other similar arrangements.

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However, we may be unable to raise additional funds or enter into such other arrangements when needed on favorable terms or at all. To the extent that we raise additional capital through the sale of equity or convertible debt securities, the ownership interest of our stockholders will be or could be diluted, and the terms of these securities may include liquidation or other preferences that adversely affect the rights of our common stockholders. Debt financing and preferred equity financing, if available, may involve agreements that include covenants limiting or restricting our ability to take specific actions, such as incurring additional debt, making capital expenditures or declaring dividends. If we raise funds through collaborations, licenses and other similar arrangements with third parties, we may have to relinquish valuable rights to our technologies, future revenue streams, research programs or product candidates or grant licenses on terms that may not be favorable to us and/or may reduce the value of our common stock. Our failure to raise capital or enter into such other arrangements when needed could have a negative impact on our financial condition and on our ability to pursue our business plans and strategies. If we are unable to raise additional capital when needed, we could be forced to delay, limit, reduce or terminate seralutinib development or future commercialization efforts or grant rights to develop and market seralutinib even if we would otherwise prefer to develop and market seralutinib ourselves.

Recent Accounting Pronouncements

See Note 2 to our consolidated financial statements included elsewhere in this annual report.

Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations.

You should read the following discussion and analysis of our financial condition and results of operations together with our consolidated financial statements and related notes included elsewhere in this annual report. This discussion and analysis contains forward-looking statements based upon our current beliefs, plans and expectations that involve risks, uncertainties and assumptions. Our actual results may differ materially from those anticipated in these forward-looking statements as a result of various factors, including those set forth under “Risk Factors” or in other parts of this annual report.

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Overview

We are a clinical-stage biopharmaceutical company focused on discovering, acquiring, developing and commercializing therapeutics in the disease areas of immunology, inflammation and oncology. We are developing seralutinib for the treatment of pulmonary arterial hypertension, or PAH. In December 2022, we announced positive topline results from the Phase 2 TORREY Study in PAH patients. Upon completion of the 24-week blinded portion of the Phase 2 TORREY Study,

patients were able to enroll into an open-label extension trial. We anticipate reporting results from this ongoing

open-label extension trial in the middle of 2023.We expect to initiate a Phase 3 program in PAH in the second half of 2023. We are developing GB5121 for the treatment of relapsed / refractory primary CNS lymphoma, or PCNSL, and we commenced enrolling healthy volunteers in a Phase 1 clinical trial in the second quarter of 2021, and we commenced the Phase 1b/2 STAR CNS Study in relapsed / refractory PCNSL and other rare CNS malignancies in the fourth quarter of 2022. Based upon the benefit / risk profile observed to date and a prioritization of resources to support the seralutinib program, we have decided to pause enrollment in the Phase 1b/2 STAR CNS Study. We plan to discuss available data with the study's Data Review Committee to determine next steps. We are developing GB7208 for the treatment of multiple sclerosis. GB7208 is currently undergoing preclinical testing. We also have multiple preclinical programs at various stages of development in the therapeutic areas of immunology, inflammation and oncology. We have assembled a deeply experienced and highly skilled group of industry veterans, scientists, clinicians and key opinion leaders from leading biotechnology and pharmaceutical companies, as well as leading academic centers from around the world. Our employees are a team of highly dedicated, passionate individuals who pride themselves on a culture of respect, humility, transparency, inclusion, dedication, collaboration and fun. Our ultimate goal is to enhance and extend the lives of patients.

We were incorporated in October 2015 and commenced operations in 2017. To date, we have focused primarily on organizing and staffing our company, business planning, raising capital, identifying, acquiring and in-licensing our product candidates and conducting preclinical studies and clinical trials. We have funded our operations primarily through equity and debt financings. We raised $1,062.1 million from October 2017 through December 31, 2022 through the sale of Series A and B convertible preferred stock financings, issuance of convertible notes, proceeds from our IPO completed in February 2019, proceeds from our Credit Facility, proceeds from our concurrent underwritten public offerings of 5.00% convertible senior notes due 2027, or the 2027 Notes, and our common stock in May 2020 and proceeds from a private placement of our common stock in July 2022. As of December 31, 2022, we had $255.7 million in cash, cash equivalents and marketable securities.

We have incurred significant operating losses since our inception and expect to continue to incur significant operating losses for the foreseeable future. For the years ended December 31, 2022 and 2021, our net loss was $229.4 million and $234.0 million, respectively. As of December 31, 2022, we had an accumulated deficit of $1,032.2 million. We expect our expenses and operating losses will increase substantially as we conduct our ongoing and planned clinical trials, continue our research and development activities and conduct preclinical studies, and seek regulatory approvals for our product candidates, as well as hire additional personnel, protect our intellectual property and incur additional costs associated with being a public company. In addition, as our product candidates progress through development and toward commercialization, we will need to make milestone payments to the licensors and other third parties from whom we have in-licensed or acquired our product candidates, including seralutinib. Our net losses may fluctuate significantly from quarter-to-quarter and year-to-year, depending in particular on the timing of our clinical trials and preclinical studies and our expenditures on other research and development activities.

We do not expect to generate any revenue from product sales unless and until we successfully complete development and obtain regulatory approval for one or more of our product candidates, which we expect will take a number of years. If we obtain regulatory approval for any of our product candidates, we expect to incur significant commercialization expenses related to product sales, marketing, manufacturing and distribution. Accordingly, until such time as we can generate substantial product revenues to support our cost structure, if ever, we expect to finance our cash needs through equity offerings, debt financings or other capital sources, including potentially collaborations, licenses and other similar arrangements. However, we may be unable to raise additional funds or enter into such other arrangements when needed on favorable terms or at all. Our failure to raise capital or enter into such other arrangements when needed could have a negative impact on our financial condition and on our ability to pursue our business plans and strategies. If we are unable to raise additional capital when needed, we could be forced to delay, limit, reduce or terminate our product candidate development or future commercialization efforts or grant rights to develop and market our product candidates even if we would otherwise prefer to develop and market such product candidates ourselves.

COVID-19 Pandemic

As we continue to actively advance our programs, we are in close contact with our principal investigators and clinical sites and continue to assess any impacts of the ongoing COVID-19 global pandemic on our drug manufacturing, nonclinical activities, clinical trials, expected timelines and costs on an ongoing basis. In addition, while we are continuing the clinical trials

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we have underway in sites across the globe, COVID-19 precautions and related staffing shortages at sites and key vendors have delayed, such as the temporary closure of enrollment in 2020 at certain sites in our ongoing Phase 2 trial for seralutinib in PAH, and may continue to delay completion of our current and future trials and may directly or indirectly impact the timeline for data readouts, initiation of, as well as monitoring, data collection and analysis and other related activities for some of our current and future clinical trials. In light of the COVID-19 pandemic, and consistent with the FDA’s updated industry guidance for conducting clinical trials, clinical trials may be deprioritized in favor of treating patients who have contracted the virus or to prevent the spread of the virus. The direct and indirect impacts of COVID-19 on our business could alter our forecasted timelines, which could have a material adverse effect on our business, results of operations and financial condition. We will continue to evaluate the impact of the COVID-19 pandemic on our business.

Components of Results of Operations

Revenue

We have not generated any revenue since our inception and do not expect to generate any revenue from the sale of products for the foreseeable future.

Operating expenses

Research and development

Research and development expenses relate primarily to preclinical and clinical development of our product candidates and discovery efforts, as well as our discontinued clinical product candidates. Research and development expenses are recognized as incurred and payments made prior to the receipt of goods or services to be used in research and development are capitalized until the goods or services are received.

Research and development expenses include or could include:

•salaries, payroll taxes, employee benefits, and stock-based compensation charges for those individuals involved in research and development efforts;

•external research and development expenses incurred under agreements with contract research organizations, or CROs, investigative sites and consultants to conduct our clinical trials and preclinical and non-clinical studies;

•laboratory supplies;

•costs related to manufacturing our product candidates for clinical trials and preclinical studies, including fees paid to third-party manufacturers;

•costs related to compliance with regulatory requirements; and

•facilities, depreciation and other allocated expenses, which include direct and allocated expenses for rent, maintenance of facilities, insurance, equipment and other supplies.

Our direct research and development expenses consist principally of external costs, such as fees paid to CROs, investigative sites and consultants in connection with our clinical trials, preclinical and non-clinical studies, and costs related to manufacturing clinical trial materials. We deploy our personnel and facility related resources across all of our research and development activities. We track external costs and personnel expense on a program-by-program basis and allocate common expenses, such as facility related resources, to each program based on the personnel resources allocated to such program. Stock-based compensation and personnel and common expenses not attributable to a specific program are considered unallocated research and development expenses.

We expect our research and development expenses for the foreseeable future to remain relatively flat as we continue the development of our product candidates and conduct discovery and research activities for our preclinical programs. We cannot determine with certainty the timing of initiation, the duration or the completion costs of current or future preclinical studies and clinical trials of our product candidates due to the inherently unpredictable nature of preclinical and clinical development. Clinical and preclinical development timelines, the probability of success and development costs can differ materially from expectations. We anticipate that we will make determinations as to which product candidates to pursue and how much funding to direct to each product candidate on an ongoing basis in response to the results of ongoing and future

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preclinical studies and clinical trials, regulatory developments and our ongoing assessments as to each product candidate’s commercial potential. We will need to raise substantial additional capital in the future.

Our clinical development costs may vary significantly based on factors such as:

•per patient trial costs;

•the number of trials required for approval;

•the number of sites included in the trials;

•the countries in which the trials are conducted;

•the length of time required to enroll eligible patients;

•the number of patients that participate in the trials;

•the number of doses that patients receive;

•the drop-out or discontinuation rates of patients;

•potential additional safety monitoring requested by regulatory agencies;

•the duration of patient participation in the trials and follow-up;

•the cost and timing of manufacturing our product candidates;

•the costs incurred as a result of the COVID-19 pandemic, including clinical trial delays;

•the phase of development of our product candidates; and

•the efficacy and safety profile of our product candidates.

In process research and development

In process research and development, or IPR&D, expenses include IPR&D acquired as part of an asset acquisition or in-license for which there is no alternative future use, are expensed as incurred.

IPR&D expenses consist of our upfront and milestone payments made to Pulmokine, Inc., in connection with the in-license of seralutinib and upfront and milestone payments made in connection with the acquisition of certain preclinical programs.

General and administrative

General and administrative expenses consist primarily of salaries and employee-related costs, including stock-based compensation, for personnel in executive, finance and other administrative functions. Other significant costs include facility-related costs, legal fees relating to intellectual property and corporate matters, professional fees for accounting and consulting services and insurance costs.

We expect our general and administrative expenses for the foreseeable future to remain relatively flat to support our current infrastructure and continued costs of operating as a public company. These expenses will likely include audit, legal, regulatory, and tax-related services associated with maintaining compliance with exchange listing and SEC requirements, director and officer insurance premiums, and investor relations costs associated with operating as a public company.

Other income (expense), net

Other income (expense), net consists of (1) interest income on our cash, cash equivalents and marketable securities, (2) sublease income, (3) interest expense related to our Credit Facility and our 2027 Notes, and (4) other miscellaneous income (expense).

Critical Accounting Policies and Estimates

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Our management’s discussion and analysis of our financial condition and results of operations are based on our consolidated financial statements, which have been prepared in accordance with generally accepted accounting principles in the United States, or GAAP. The preparation of these financial statements requires us to make judgments and estimates that affect the reported amounts of assets, liabilities, and expenses and the disclosure of contingent assets and liabilities in our consolidated financial statements. We base our estimates on historical experience, known trends and events, and various other factors that are believed to be reasonable under the circumstances. Actual results may differ from these estimates under different assumptions or conditions (See Note 2 to our consolidated financial statements).

Accrued expenses

As part of the process of preparing our consolidated financial statements, we are required to estimate our accrued expenses as of each balance sheet date. This process involves reviewing open contracts and purchase orders, communicating with our personnel to identify services that have been performed on our behalf and estimating the level of service performed and the associated cost incurred for the service when we have not yet been invoiced or otherwise notified of the actual cost. We make estimates of our accrued expenses as of each balance sheet date based on facts and circumstances known to us at that time. We periodically confirm the accuracy of our estimates with the service providers and make adjustments if necessary. The significant estimates in our accrued research and development expenses include the costs incurred for services performed by our vendors in connection with research and development activities for which we have not yet been invoiced.

We base our expenses related to research and development activities on our estimates of the services received and efforts expended pursuant to quotes and contracts with vendors that conduct research and development on our behalf. The financial terms of these agreements are subject to negotiation, vary from contract to contract and may result in uneven payment flows. There may be instances in which payments made to our vendors will exceed the level of services provided and result in a prepayment of the research and development expense. In accruing service fees, we estimate the time period over which services will be performed and the level of effort to be expended in each period. If the actual timing of the performance of services or the level of effort varies from our estimate, we adjust the accrual or prepaid expense accordingly. Advance payments for goods and services that will be used in future research and development activities are expensed when the activity has been performed or when the goods have been received rather than when the payment is made.

Although we do not expect our estimates to be materially different from amounts actually incurred, if our estimates of the status and timing of services performed differ from the actual status and timing of services performed, it could result in us reporting amounts that are too high or too low in any particular period. To date, there have been no material differences between our estimates of such expenses and the amounts actually incurred.

Results of Operations for the Years Ended December 31, 2022 and 2021

The following table sets forth our selected statements of operations data for the years ended December 31, 2022 and 2021:

Operating Expenses

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Research and development

Research and development expenses were $170.9 million for the year ended December 31, 2022, compared to $170.3 million for the year ended December 31, 2021, for an increase of $0.7 million, which was primarily attributable to an increase of $23.1 million of costs associated with preclinical studies and clinical trials for GB5121 and an increase of $16.5 million of costs associated with preclinical studies and clinical trials for seralutinib; offset by a decrease of $20.9 million of costs associated with preclinical studies and clinical trials for terminated GB004 program, a decrease of $10.3 million of costs associated with preclinical studies for other programs, and a decrease of $7.7 million of costs associated with preclinical studies and clinical trials for other terminated programs.

The following table shows our research and development expenses by program for the years ended December 31, 2022 and 2021:

In process research and development

There were no significant IPR&D expenses for the years ended December 31, 2022 and 2021.

General and administrative

General and administrative expenses were $47.6 million for the year ended December 31, 2022, compared to $45.8 million for the year ended December 31, 2021, for an increase of $1.8 million, which was primarily attributable to a $5.1 million increase in stock-based compensation costs; offset by a decrease of $2.4 million of accrued costs associated with a settlement of outstanding securities litigation in 2021 and a $1.0 million decrease in insurance costs.

Other expense, net

Other expense, net was $10.8 million for the year ended December 31, 2022, compared to other expense, net of $17.9 million for the year ended December 31, 2021, for a decrease of $7.1 million, which was primarily attributable to a $5.6 million decrease in interest expense, an increase of $2.2 million of other income related to investment accretion and amortization and a $0.8 million increase in interest income earned on our cash, cash equivalents and marketable securities during the period; offset by a $1.1 million decrease in sublease income and a decrease of $0.5 million of other income.

Results of Operations for the Years Ended December 31, 2021 and 2020

The discussion of our financial condition and results of operations for the year ended December 31, 2020 and the comparison of 2021 and 2020 results included in Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations in our Annual Report on Form 10-K for the year ended December 31, 2021 is incorporated by reference into this MD&A.

Liquidity and Capital Resources

We have incurred substantial operating losses since our inception and expect to continue to incur significant operating losses for the foreseeable future and may never become profitable. As of December 31, 2022 and 2021, we had an accumulated deficit of $1,032.2 million and $811.5 million, respectively.

Our primary use of cash is to fund operating expenses, which consist primarily of research and development expenditures, and to a lesser extent, general and administrative expenditures. Cash used to fund operating expenses is impacted by the timing of when we pay these expenses, as reflected in the change in our outstanding accounts payable and accrued expenses. We may also use cash on hand to repurchase 2027 Notes through open-market transactions, including through a Rule 10b5-1 trading plan to facilitate open-market repurchases, or otherwise, from time to time.

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Under our license agreement with Pulmokine, as well as our other license and acquisition agreements, we have payment obligations that are contingent upon future events such as our achievement of specified development, regulatory and commercial milestones and are required to make royalty payments in connection with the sale of products developed under those agreements. As of December 31, 2022, we were unable to estimate the timing or likelihood of achieving the milestones or making future product sales. Other contractual obligations include future payments under our Credit Facility, 2027 Notes and existing operating leases.

From our inception through the year ended December 31, 2022, our operations have been financed primarily by gross proceeds of $1,062.1 million from the sale of our convertible preferred stock, issuance of convertible notes, proceeds from our IPO, proceeds from our Credit Facility, proceeds from our concurrent underwritten public offerings of 2027 Notes and common stock, and proceeds from our private placement of common stock. As of December 31, 2022, we had cash, cash equivalents and marketable securities of $255.7 million. Cash in excess of immediate requirements is invested in accordance with our investment policy, primarily with a view to capital preservation and liquidity.

On May 2, 2019, we entered into a credit, guaranty and security agreement, as amended on September 18, 2019 and July 2, 2020, pursuant to which the lenders party thereto agreed to make term loans available to us for working capital and general business purposes, in a principal amount of up to $150.0 million in term loan commitments, including a $30.0 million term loan which was funded at the closing date, with the ability to access the remaining $120.0 million in two additional tranches (each $60.0 million), subject to specified availability periods, the achievement of certain clinical development milestones, minimum cash requirements and other customary conditions, or the Credit Facility. As of December 31, 2022, no tranches under the Credit Facility were available to be drawn.

On April 10, 2020, we filed a registration statement on Form S-3, or the 2020 Shelf Registration Statement, covering the offering from time to time of common stock, preferred stock, debt securities, warrants and units, which registration statement became automatically effective on April 10, 2020.

On May 21, 2020, we issued $200.0 million aggregate principal amount 5.00% convertible senior notes due 2027 in a registered public offering. The interest rate on the 2027 Notes is fixed at 5.00% per annum. Interest is payable semi-annually in arrears on June 1 and December 1 of each year commencing on December 1, 2020. The total net proceeds from the 2027 Notes, after deducting the underwriting discounts and commissions and other offering costs, were approximately $193.6 million. Concurrent with the registered underwritten public offering of the 2027 Notes, we completed an underwritten public offering of 9,433,963 shares of our common stock. We received net proceeds of $117.1 million, after deducting underwriting discounts and commissions and other offering costs. Our concurrent offerings of 2027 Notes and common stock were registered pursuant to the 2020 Shelf Registration Statement.

On March 3, 2022, we filed a registration statement on Form S-3 covering the offering from time to time of common stock, preferred stock, debt securities, warrants and units, which registration statement became automatically effective on March 3, 2022.

On July 15, 2022, we completed a private placement of 16,649,365 shares of our common stock. The aggregate gross proceeds for the private placement were approximately $120.1 million, before deducting offering expenses. On August 9, 2022, we filed a registration statement on Form S-3 registering the resale of the shares of common stock issued in the private placement, which registration statement became automatically effective on August 9, 2022.

Additional information about our long-term borrowings is presented in Note 5 “Indebtedness” to the Notes to Consolidated Financial Statements included in Part II, Item 8, of this Form 10-K, herein by this reference.

The following table shows a summary of our cash flows for each of the years shown below:

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Operating activities

During the year ended December 31, 2022, operating activities used approximately $187.0 million of cash, primarily resulting from a net loss of $229.4 million and payments against operating lease liabilities of $2.7 million, partially reduced by stock-based compensation expense of $42.6 million and amortization of operating lease right-of-use assets of $2.6 million.

During the year ended December 31, 2021, operating activities used approximately $188.9 million of cash, primarily resulting from a net loss of $234.0 million, partially reduced by stock-based compensation expense of $32.0 million, amortization of long-term debt discount and issuance costs of $6.7 million and accrued research and development expenses of $5.8 million.

During the year ended December 31, 2020, operating activities used approximately $176.4 million of cash, primarily resulting from a net loss of $243.4 million, partially reduced by stock-based compensation expense of $38.7 million, IPR&D expenses of $23.4 million and amortization of long-term debt discount and issuance costs of $3.9 million.

Investing activities

During the year ended December 31, 2022, investing activities used approximately $1.0 million of cash, primarily resulting from the purchase of marketable securities of $238.0 million and the purchase of property and equipment of $0.4 million, partially offset by maturities of marketable securities of $237.5 million.

During the year ended December 31, 2021, investing activities used approximately $117.4 million of cash, primarily resulting from the purchase of marketable securities of $152.0 million, partially offset by maturities of marketable securities of $36.2 million.

During the year ended December 31, 2020, investing activities provided approximately $215.3 million of cash, primarily resulting from the sales and maturities of marketable securities of $349.2 million, partially offset by the purchase of marketable securities of $109.0 million and upfront and milestone payments of $23.4 million made to third parties in connection with the in-license or acquisition of our clinical and preclinical programs.

Financing activities

During the year ended December 31, 2022, financing activities provided $117.1 million of cash, resulting from the proceeds from the private offering of $119.9 million, the proceeds from the exercise of stock options of $1.7 million, and from proceeds from the purchase of shares pursuant to our 2019 Employee Stock Purchase Plan, or ESPP, of $1.2 million, partially offset by the principal repayments of long-term debt of $5.8 million.

During the year ended December 31, 2021, financing activities provided $3.3 million of cash, resulting from the proceeds from the exercise of stock options of $2.0 million, and from the purchase of shares pursuant to the ESPP of $1.3 million.

During the year ended December 31, 2020, financing activities provided $312.5 million of cash, primarily resulting from the concurrent registered underwritten public offerings of 2027 Notes and common stock for net proceeds of $193.6 million and $117.1 million, respectively.

Funding requirements

Based on our current operating plan, we believe that our existing cash, cash equivalents and marketable securities, and access to our Credit Facility, will be sufficient to fund our operations into the second quarter of 2024. However, our forecast of the period of time through which our financial resources will be adequate to support our operations is a forward-looking statement that involves risks and uncertainties, and actual results could vary materially. We have based this estimate on assumptions that may prove to be wrong, and we could use our capital resources sooner than we expect. Additionally, the process of testing product candidates in clinical trials is costly, and the timing of progress and expenses in these trials is uncertain.

Our future capital requirements will depend on many factors, including:

•the type, number, scope, progress, expansions, results, costs and timing of, our preclinical studies and clinical trials of our product candidates which we are pursuing or may choose to pursue in the future;

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•the costs and timing of manufacturing for our product candidates;

•the costs, timing and outcome of regulatory review of our product candidates;

•the costs of obtaining, maintaining and enforcing our patents and other intellectual property rights;

•our efforts to enhance operational systems and hire additional personnel to satisfy our obligations as a public company, including enhanced internal controls over financial reporting;

•the costs associated with hiring additional personnel and consultants as our preclinical and clinical activities increase;

•the timing and amount of the milestone or other payments we must make to the licensors and other third parties from whom we have in-licensed our acquired our product candidates;

•the costs and timing of establishing or securing sales and marketing capabilities if any product candidate is approved;

•our ability to achieve sufficient market acceptance, coverage and adequate reimbursement from third-party payors and adequate market share and revenue for any approved products;

•the terms and timing of establishing and maintaining collaborations, licenses and other similar arrangements;

•costs associated with any products or technologies that we may in-license or acquire; and

•any delays and cost increases that result from the COVID-19 pandemic or other epidemic diseases.

Until such time as we can generate substantial product revenues to support our cost structure, if ever, we expect to finance our cash needs through equity offerings, our Credit Facility, debt financings or other capital sources, including potentially collaborations, licenses and other similar arrangements.

However, we may be unable to raise additional funds or enter into such other arrangements when needed on favorable terms or at all. To the extent that we raise additional capital through the sale of equity or convertible debt securities, the ownership interest of our stockholders will be or could be diluted, and the terms of these securities may include liquidation or other preferences that adversely affect the rights of our common stockholders. Debt financing and preferred equity financing, if available, may involve agreements that include covenants limiting or restricting our ability to take specific actions, such as incurring additional debt, making capital expenditures or declaring dividends. If we raise funds through collaborations, licenses and other similar arrangements with third parties, we may have to relinquish valuable rights to our technologies, future revenue streams, research programs or product candidates or grant licenses on terms that may not be favorable to us and/or may reduce the value of our common stock. Our failure to raise capital or enter into such other arrangements when needed could have a negative impact on our financial condition and on our ability to pursue our business plans and strategies. If we are unable to raise additional capital when needed, we could be forced to delay, limit, reduce or terminate our product candidate development or future commercialization efforts or grant rights to develop and market our product candidates even if we would otherwise prefer to develop and market such product candidates ourselves.

Recent Accounting Pronouncements

See Note 2 to our consolidated financial statements included elsewhere in this annual report.

Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations.

You should read the following discussion and analysis of our financial condition and results of operations together with our consolidated financial statements and related notes included elsewhere in this annual report. This discussion and analysis contains forward-looking statements based upon our current beliefs, plans and expectations that involve risks, uncertainties and assumptions. Our actual results may differ materially from those anticipated in these forward-looking statements as a result of various factors, including those set forth under “Risk Factors” or in other parts of this annual report.

Overview

We are a clinical-stage biopharmaceutical company focused on discovering, acquiring, developing and commercializing therapeutics in the disease areas of immunology, inflammation and oncology. Our goal is to be an industry leader in each of these therapeutic areas and enhance and extend the lives of patients suffering from such diseases. We currently have three clinical-stage product candidates, in addition to one late-stage preclinical product candidate and five additional preclinical programs. We are developing seralutinib for the treatment of PAH and commenced enrolling patients for a Phase 2 TORREY clinical trial in PAH patients in December 2020. We expect topline results from this trial in the second half of 2022, subject to developments in the ongoing COVID-19 pandemic. We are developing GB004 for the treatment of inflammatory bowel disease, including UC and CD. We commenced enrolling patients for a Phase 2 SHIFT-UC clinical trial in UC in October 2020, and we completed enrollment in the fourth quarter of 2021. We expect topline results for the 12-week primary endpoint for this trial in the second quarter of 2022 and topline results for the week 36 treat-through endpoint from this trial in the fourth quarter of 2022. We are developing GB5121 for the treatment of PCNSL and commenced a Phase 1 study in healthy volunteers in the fourth quarter of 2021. We are developing GB7208 for the treatment of MS. GB7208 is currently undergoing preclinical testing, and pending the outcomes of our ongoing preclinical work, we expect to initiate a Phase 1 study in healthy volunteers in the second half of 2022.

We were incorporated in October 2015 and commenced operations in 2017. To date, we have focused primarily on organizing and staffing our company, business planning, raising capital, identifying, acquiring and in-licensing our product candidates and conducting preclinical studies and early clinical trials. We have funded our operations primarily through equity and debt financings. We raised $954.8 million from October 2017 through December 31, 2021 through Series A and B convertible preferred stock financings, a convertible note financing, our IPO completed in February 2019, proceeds from our Credit Facility, and proceeds from our concurrent underwritten public offerings of 5.00% convertible Notes due 2027 or the "2027 Notes" and proceeds from our common stock in May 2020. As of December 31, 2021, we had $325.2 million in cash, cash equivalents and marketable securities.

We have incurred significant operating losses since our inception and expect to continue to incur significant operating losses for the foreseeable future. For the years ended December 31, 2021 and 2020, our net loss was $234.0 million and $243.4 million, respectively. As of December 31, 2021, we had an accumulated deficit of $811.5 million. We expect our expenses and operating losses will increase substantially as we conduct our ongoing and planned clinical trials, continue our research and development activities and conduct preclinical studies, and seek regulatory approvals for our product candidates, as well as hire additional personnel, protect our intellectual property and incur additional costs associated with being a public company. In addition, as our product candidates progress through development and toward commercialization, we will need to make milestone payments to the licensors and other third parties from whom we have in-licensed or acquired our product candidates, including seralutinib and GB004. Our net losses may fluctuate significantly from quarter-to-quarter and year-to-year, depending in particular on the timing of our clinical trials and preclinical studies and our expenditures on other research and development activities.

We do not expect to generate any revenue from product sales unless and until we successfully complete development and obtain regulatory approval for one or more of our product candidates, which we expect will take a number of years. If we obtain regulatory approval for any of our product candidates, we expect to incur significant commercialization expenses related to product sales, marketing, manufacturing and distribution. Accordingly, until such time as we can generate substantial product revenues to support our cost structure, if ever, we expect to finance our cash needs through equity offerings, debt financings or other capital sources, including potentially collaborations, licenses and other similar arrangements. However, we may be unable to raise additional funds or enter into such other arrangements when needed on favorable terms or at all. Our failure to raise capital or enter into such other arrangements when needed could have a negative impact on our financial condition and on our

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ability to pursue our business plans and strategies. If we are unable to raise additional capital when needed, we could be forced to delay, limit, reduce or terminate our product candidate development or future commercialization efforts or grant rights to develop and market our product candidates even if we would otherwise prefer to develop and market such product candidates ourselves.

COVID-19 Pandemic

The COVID-19 pandemic continues to rapidly evolve. The pandemic and government measures taken in response have had a significant impact, both direct and indirect, on businesses and commerce, as worker shortages have occurred; supply chains have been disrupted; facilities and production have been suspended; and demand for certain goods and services, such as medical services and supplies, has spiked, while demand for other goods and services, such as travel, has fallen. The extent to which the COVID-19 pandemic may impact our business, including our preclinical studies, clinical trials, and financial condition will depend on future developments, which are highly uncertain and cannot be predicted with confidence, such as the continued geographic spread of variants, the duration of the pandemic, the timing and effectiveness of vaccine distribution, travel restrictions and social distancing in the United States and other countries, business closures or business disruptions and the effectiveness of actions taken in the United States and other countries to contain and treat the disease. With a focus on employee safety and well-being during the COVID-19 pandemic, we have transitioned to a hybrid work model with our employees generally working both remotely and onsite. We anticipate we will continue to use this model going forward as we provide our employees with the flexibility and tools to support their well-being and effectiveness in an evolving public health environment. To date, we have been able to continue to supply our product candidates to our patients currently enrolled in our clinical trials, including our Phase 2 clinical trials of seralutinib and GB004 and Phase 1 study of GB5121, and do not currently anticipate any interruptions in supply. In addition, while we are continuing the clinical trials we have underway in sites across the globe, COVID-19 precautions and related staffing shortages at sites and key vendors have delayed, such as the temporary closure of enrollment in 2020 at certain sites in our ongoing Phase 2 trial for seralutinib in PAH, and may continue to delay completion of our current and future trials and may directly or indirectly impact the timeline for data readouts, initiation of, as well as monitoring, data collection and analysis and other related activities for, some of our current and future clinical trials. For example, our current expectations for how we will continue to enroll our Phase 2 clinical trial of seralutinib are based on an assumption that clinical trial and healthcare activities remain somwhat normal, and clinical sites stay open in the first half of 2022 and that we do not experience another slowdown in enrollment such as what we experienced during the surge of the COVID-19 Delta variant in the summer of 2021. In particular, with respect to seralutinib, some PAH clinical trial sites may limit operations and enrollment as PAH patients may be at a higher risk of COVID-19 complications than the general population. Therefore, our assumptions around enrollment timing may prove to be incorrect, in particular if COVID-19 continues to spread and/or surge. In light of recent developments relating to the COVID-19 pandemic, and consistent with the FDA’s updated industry guidance for conducting clinical trials, clinical trials may be deprioritized in favor of treating patients who have contracted the virus or to prevent the spread of the virus. This may lead to clinical trial protocol deviations or to discontinuation of treatment for patients who are currently enrolled in our trials. Any delays in the completion of our clinical trials, data analysis or readouts and any disruption in our supply chain could have a material adverse effect on our business, results of operations and financial condition. The full extent to which the COVID-19 pandemic will directly or indirectly impact our business, results of operations and financial condition, will depend on future developments that are highly uncertain, including as a result of new information that may emerge concerning COVID-19 and the actions taken to contain or treat it, as well as the economic impact on local, regional, national and international markets.

Components of Results of Operations

Operating expenses

Research and development

Research and development expenses relate primarily to preclinical and clinical development of our product candidates and discovery efforts. Research and development expenses are recognized as incurred and payments made prior to the receipt of goods or services to be used in research and development are capitalized until the goods or services are received.

Research and development expenses include or could include:

•salaries, payroll taxes, employee benefits, and stock-based compensation charges for those individuals involved in research and development efforts;

•external research and development expenses incurred under agreements with contract research organizations, or CROs, investigative sites and consultants to conduct our clinical trials and preclinical and non-clinical studies;

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•laboratory supplies;

•costs related to manufacturing our product candidates for clinical trials and preclinical studies, including fees paid to third-party manufacturers;

•costs related to compliance with regulatory requirements; and

•facilities, depreciation and other allocated expenses, which include direct and allocated expenses for rent, maintenance of facilities, insurance, equipment and other supplies.

Our direct research and development expenses consist principally of external costs, such as fees paid to CROs, investigative sites and consultants in connection with our clinical trials, preclinical and non-clinical studies, and costs related to manufacturing clinical trial materials. We deploy our personnel and facility related resources across all of our research and development activities. We track external costs and personnel expense on a program-by-program basis and allocate common expenses, such as facility related resources, to each program based on the personnel resources allocated to such program. Stock-based compensation and personnel and common expenses not attributable to a specific program are considered unallocated research and development expenses.

We plan to substantially increase our research and development expenses for the foreseeable future as we continue the development of our product candidates and conduct discovery and research activities for our preclinical programs. We cannot determine with certainty the timing of initiation, the duration or the completion costs of current or future preclinical studies and clinical trials of our product candidates due to the inherently unpredictable nature of preclinical and clinical development. Clinical and preclinical development timelines, the probability of success and development costs can differ materially from expectations. We anticipate that we will make determinations as to which product candidates to pursue and how much funding to direct to each product candidate on an ongoing basis in response to the results of ongoing and future preclinical studies and clinical trials, regulatory developments and our ongoing assessments as to each product candidate’s commercial potential. We will need to raise substantial additional capital in the future.

Our clinical development costs may vary significantly based on factors such as:

•the costs incurred as a result of the COVID-19 pandemic, including clinical trial delays;

•per patient trial costs;

•the number of trials required for approval;

•the number of sites included in the trials;

•the countries in which the trials are conducted;

•the length of time required to enroll eligible patients;

•the number of patients that participate in the trials;

•the number of doses that patients receive;

•the drop-out or discontinuation rates of patients;

•potential additional safety monitoring requested by regulatory agencies;

•the duration of patient participation in the trials and follow-up;

•the cost and timing of manufacturing our product candidates;

•the phase of development of our product candidates; and

•the efficacy and safety profile of our product candidates.

In process research and development

In process research and development, or IPR&D, expenses include IPR&D acquired as part of an asset acquisition or in-license for which there is no alternative future use, are expensed as incurred.

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IPR&D expenses consist of our upfront and milestone payments made to Pulmokine, Inc., in connection with the in-license of seralutinib, our upfront payments made to Aadi in connection with the in-license and subsequent amendment of the in-license of GB004, our upfront and milestone payments made to Adhaere Pharmaceuticals, Inc., or Adhaere, in connection with the acquisition of GB1275, and upfront and milestone payments made in connection with the acquisition of certain preclinical programs.

General and administrative

General and administrative expenses consist primarily of salaries and employee-related costs, including stock-based compensation, for personnel in executive, finance and other administrative functions. Other significant costs include facility-related costs, legal fees relating to intellectual property and corporate matters, professional fees for accounting and consulting services and insurance costs.

We expect our general and administrative expenses will increase for the foreseeable future to support our expanded infrastructure and increased costs of operating as a public company. These increases will likely include increased expenses related to audit, legal, regulatory, and tax-related services associated with maintaining compliance with exchange listing and SEC requirements, director and officer insurance premiums, and investor relations costs associated with operating as a public company.

Other income (expense), net

Other income (expense), net consists of (1) interest income on our cash, cash equivalents and marketable securities, (2) sublease income, (3) interest expense related to our Credit Facility and our 2027 Notes, and (4) other miscellaneous income (expense).

Critical Accounting Policies and Estimates

Our management’s discussion and analysis of our financial condition and results of operations are based on our consolidated financial statements, which have been prepared in accordance with generally accepted accounting principles in the United States, or GAAP. The preparation of these financial statements requires us to make judgments and estimates that affect the reported amounts of assets, liabilities, revenues, and expenses and the disclosure of contingent assets and liabilities in our consolidated financial statements. We base our estimates on historical experience, known trends and events, and various other factors that are believed to be reasonable under the circumstances. Actual results may differ from these estimates under different assumptions or conditions (See Note 2 to our consolidated financial statements).

Accrued expenses

As part of the process of preparing our consolidated financial statements, we are required to estimate our accrued expenses as of each balance sheet date. This process involves reviewing open contracts and purchase orders, communicating with our personnel to identify services that have been performed on our behalf and estimating the level of service performed and the associated cost incurred for the service when we have not yet been invoiced or otherwise notified of the actual cost. We make estimates of our accrued expenses as of each balance sheet date based on facts and circumstances known to us at that time. We periodically confirm the accuracy of our estimates with the service providers and make adjustments if necessary. The significant estimates in our accrued research and development expenses include the costs incurred for services performed by our vendors in connection with research and development activities for which we have not yet been invoiced.

We base our expenses related to research and development activities on our estimates of the services received and efforts expended pursuant to quotes and contracts with vendors that conduct research and development on our behalf. The financial terms of these agreements are subject to negotiation, vary from contract to contract and may result in uneven payment flows. There may be instances in which payments made to our vendors will exceed the level of services provided and result in a prepayment of the research and development expense. In accruing service fees, we estimate the time period over which services will be performed and the level of effort to be expended in each period. If the actual timing of the performance of services or the level of effort varies from our estimate, we adjust the accrual or prepaid expense accordingly. Advance payments for goods and services that will be used in future research and development activities are expensed when the activity has been performed or when the goods have been received rather than when the payment is made.

Although we do not expect our estimates to be materially different from amounts actually incurred, if our estimates of the status and timing of services performed differ from the actual status and timing of services performed, it could

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result in us reporting amounts that are too high or too low in any particular period. To date, there have been no material differences between our estimates of such expenses and the amounts actually incurred.

Convertible Senior Notes

In accounting for the issuance of the 2027 Notes, we separated the 2027 Notes into liability and equity components at issuance. The carrying amount of the liability component was calculated by measuring the fair value of similar debt instruments that do not have associated convertible features. The carrying amount of the equity component representing the conversion option was determined by deducting the fair value of the liability component from the par value of the 2027 Notes. The equity component is not remeasured as long as it continues to meet the condition for equity classification. The excess of the principal amount of the liability component over its carrying amount (“debt discount”) is amortized to interest expense over the term of the 2027 Notes.

We allocated the issuance costs incurred to the liability and equity components of the 2027 Notes based on their relative fair values. Issuance costs attributable to the liability component were recorded as a reduction to the liability portion of the 2027 Notes and are being amortized to interest expense over the term of the 2027 Notes. Issuance costs attributable to the equity component, representing the conversion option, were netted with the equity component in stockholders' equity.

Results of Operations for the Years Ended December 31, 2021 and 2020

The following table sets forth our selected statements of operations data for the years ended December 31, 2021 and 2020:

Operating expenses

Research and development

Research and development expenses were $170.3 million for the year ended December 31, 2021, compared to $160.9 million for the year ended December 31, 2020, for an increase of $9.4 million, which was primarily attributable to an increase of $18.0 million of costs associated with preclinical studies and clinical trials for GB004, an increase of $11.9 million of costs associated with preclinical studies and clinical trials for GB002, an increase of $16.2 million of costs associated with preclinical studies and clinical trials for GB5121, and an increase of $6.2 million of costs associated with preclinical studies for other programs; offset by a decrease of $34.6 million of costs associated with preclinical studies and clinical trials for GB001 and a decrease of $8.3 million of costs associated with preclinical studies and clinical trials for GB1275.

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The following table shows our research and development expenses by program for the years ended December 31, 2021 and 2020:

In process research and development

There were no significant IPR&D expenses for the year ended December 31, 2021. IPR&D expenses for the year ended December 31, 2020 were $23.4 million, which was primarily attributable to a $15.0 million upfront payment to Aadi in connection with the amendment to the in-license agreement of GB004 and a $5.0 million milestone payment to Pulmokine for the initiation of the Phase 2 clinical trial for seralutinib.

General and administrative

General and administrative expenses were $45.8 million for the year ended December 31, 2021, compared to $49.7 million for the year ended December 31, 2020, for a decrease of $3.9 million, which was primarily attributable to a $6.7 million decrease in stock-based compensation costs; offset by $2.4 million of accrued costs associated with a settlement of outstanding securities litigation and a $0.5 million increase in insurance costs.

Other expense, net

Other expense, net was $17.9 million for the year ended December 31, 2021, compared to other expense, net of $9.4 million for the year ended December 31, 2020, for an increase of $8.5 million, which was primarily attributable to a $6.8 million increase in interest expense, a $2.7 million decrease in interest income earned on our cash, cash equivalents and marketable securities during the period, offset by an increase of $1.3 million of sublease income.

Results of Operations for the Years Ended December 31, 2020 and 2019

The discussion of our financial condition and results of operations for the year ended December 31, 2019 and the comparison of 2020 and 2019 results included in Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations in our Annual Report on Form 10-K for the year ended December 31, 2020 is incorporated by reference into this MD&A.

Liquidity and Capital Resources

We have incurred substantial operating losses since our inception and expect to continue to incur significant operating losses for the foreseeable future and may never become profitable. As of December 31, 2021 and 2020, we had an accumulated deficit of $811.5 million and $577.5 million, respectively.

Our primary use of cash is to fund operating expenses, which consist primarily of research and development expenditures, and to a lesser extent, general and administrative expenditures. Cash used to fund operating expenses is impacted by the timing of when we pay these expenses, as reflected in the change in our outstanding accounts payable and accrued expenses.

Under our license agreements with Pulmokine and Aadi, as well as our other license and acquisition agreements, we have payment obligations that are contingent upon future events such as our achievement of specified development, regulatory and commercial milestones and are required to make royalty payments in connection with the sale of products developed under those agreements. As of December 31, 2021, we were unable to estimate the timing or likelihood of achieving the milestones or making future product sales. Other contractual obligations include future payments under our Credit Facility, 2027 Notes and existing operating leases.

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From our inception through the year ended December 31, 2021, our operations have been financed primarily by gross proceeds of $942.0 million from the sale of our convertible preferred stock, convertible promissory note, proceeds from our IPO, proceeds from our Credit Facility, and proceeds from our concurrent underwritten public offerings of 2027 Notes and common stock. As of December 31, 2021, we had cash, cash equivalents and marketable securities of $325.2 million. Cash in excess of immediate requirements is invested in accordance with our investment policy, primarily with a view to capital preservation and liquidity.

On February 12, 2019, we closed our IPO and the underwriters in the IPO purchased 19,837,500 shares, including the full exercise of their option to purchase additional shares of common stock. The net proceeds from the IPO were $291.3 million, after deducting underwriting discounts and commissions and estimated offering costs. In connection with the closing of the IPO, the outstanding shares of our convertible preferred stock were converted into shares of common stock at a ratio of 4.5-to-one.

On May 2, 2019, we entered into a credit, guaranty and security agreement, as amended on September 18, 2019 and July 2, 2020, pursuant to which the lenders party thereto agreed to make term loans available to us for working capital and general business purposes, in a principal amount of up to $150.0 million in term loan commitments, including a $30.0 million term loan which was funded at the closing date, with the ability to access the remaining $120.0 million in two additional tranches (each $60.0 million), subject to specified availability periods, the achievement of certain clinical development milestones, minimum cash requirements and other customary conditions, or the Credit Facility. As of December 31, 2021, no other tranches under the Credit Facility were available to be drawn.

On April 10, 2020, we filed a registration statement on Form S-3, or the Shelf Registration Statement, covering the offering from time to time of common stock, preferred stock, debt securities, warrants and units, which registration statement became automatically effective on April 10, 2020.

On May 21, 2020, we issued $200.0 million aggregate principal amount 5.00% convertible senior notes due 2027 in a registered public offering. The interest rate on the 2027 Notes is fixed at 5.00% per annum. Interest is payable semi-annually in arrears on June 1 and December 1 of each year commencing on December 1, 2020. The total net proceeds from the 2027 Notes, after deducting the underwriting discounts and commissions and other offering costs, were approximately $193.6 million. Concurrent with the registered underwritten public offering of the 2027 Notes, we completed an underwritten public offering of 9,433,963 shares of our common stock. We received net proceeds of $117.1 million, after deducting underwriting discounts and commissions and other offering costs. Our concurrent offerings of 2027 Notes and common stock were registered pursuant to the Shelf Registration Statement.

Additional information about the our long-term borrowings is presented in Note 5 “Indebtedness” to the Notes to Consolidated Financial Statements included in Part II, Item 8, of this Form 10-K, herein by this reference.

The following table shows a summary of our cash flows for each of the years shown below:

Operating activities

During the year ended December 31, 2021, operating activities used approximately $188.9 million of cash, primarily resulting from a net loss of $234.0 million, partially reduced by stock-based compensation expense of $32.0 million, amortization of long-term debt discount and issuance costs of $6.7 million and accrued research and development expenses of $5.8 million.

During the year ended December 31, 2020, operating activities used approximately $176.4 million of cash, primarily resulting from a net loss of $243.4 million, partially reduced by stock-based compensation expense of $38.7 million, IPR&D expenses of $23.4 million and amortization of long-term debt discount and issuance costs of $3.9 million.

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During the year ended December 31, 2019, operating activities used approximately $144.8 million of cash, primarily resulting from a net loss of $180.3 million, partially reduced by stock-based compensation expense of $20.8 million, and changes in operating assets and liabilities of $12.3 million. Net cash provided by changes in operating assets and liabilities consisted primarily of increases in accounts payable, accrued research and development expenses, and accrued expenses of $13.9 million, and an increase in other assets of $2.7 million due to long-term deposits for clinical development activities and property leases, partially offset by an increase in prepaid expenses and other current assets due to prepayments for clinical development activities, investments receivable, and receivables for stock option exercises of $4.4 million.

Investing activities

During the year ended December 31, 2021, investing activities used approximately $117.4 million of cash, primarily resulting from the purchase of marketable securities of $152.0 million, partially offset by maturities of marketable securities of $36.2 million.

During the year ended December 31, 2020, investing activities provided approximately $215.3 million of cash, primarily resulting from the sales and maturities of marketable securities of $349.2 million, partially offset by the purchase of marketable securities of $109.0 million and upfront and milestone payments of $23.4 million made to third parties in connection with the in-license or acquisition of our clinical and preclinical programs.

During the year ended December 31, 2019, investing activities used approximately $147.1 million of cash, primarily resulting from the purchase of marketable securities of $499.1 million, partially offset by sales and maturities of investments of $358.5 million.

Financing activities

During the year ended December 31, 2021, financing activities provided $3.3 million of cash, resulting from the proceeds from the exercise of stock options of $2.0 million, and from the purchase of shares pursuant to the Employee Stock Purchase Plan of $1.3 million.

During the year ended December 31, 2020, financing activities provided $312.5 million of cash, primarily resulting from the concurrent registered underwritten public offerings of 2027 Notes and common stock for net proceeds of $193.6 million and $117.1 million, respectively.

During the year ended December 31, 2019, financing activities provided $321.6 million of cash, primarily resulting from the net proceeds from our IPO of $291.3 million, and proceeds from our Credit Facility of $30.0 million, offset by $1.8 million of debt issuance costs.

Funding requirements

Based on our current operating plan, we believe that our existing cash, cash equivalents and marketable securities, and access to our Credit Facility, will be sufficient to fund our operations into the second half of 2023. However, our forecast of the period of time through which our financial resources will be adequate to support our operations is a forward-looking statement that involves risks and uncertainties, and actual results could vary materially. We have based this estimate on assumptions that may prove to be wrong, and we could use our capital resources sooner than we expect. Additionally, the process of testing product candidates in clinical trials is costly, and the timing of progress and expenses in these trials is uncertain.

Our future capital requirements will depend on many factors, including:

•the type, number, scope, progress, expansions, results, costs and timing of, our preclinical studies and clinical trials of our product candidates which we are pursuing or may choose to pursue in the future;

•the costs and timing of manufacturing for our product candidates;

•the costs, timing and outcome of regulatory review of our product candidates;

•the costs of obtaining, maintaining and enforcing our patents and other intellectual property rights;

•our efforts to enhance operational systems and hire additional personnel to satisfy our obligations as a public company, including enhanced internal controls over financial reporting;

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•the costs associated with hiring additional personnel and consultants as our preclinical and clinical activities increase;

•the timing and amount of the milestone or other payments we must make to the licensors and other third parties from whom we have in-licensed our acquired our product candidates;

•the costs and timing of establishing or securing sales and marketing capabilities if any product candidate is approved;

•our ability to achieve sufficient market acceptance, coverage and adequate reimbursement from third-party payors and adequate market share and revenue for any approved products;

•the terms and timing of establishing and maintaining collaborations, licenses and other similar arrangements;

•costs associated with any products or technologies that we may in-license or acquire; and

•any delays and cost increases that result from the COVID-19 pandemic.

Until such time as we can generate substantial product revenues to support our cost structure, if ever, we expect to finance our cash needs through equity offerings, our Credit Facility, debt financings or other capital sources, including potentially collaborations, licenses and other similar arrangements.

However, we may be unable to raise additional funds or enter into such other arrangements when needed on favorable terms or at all. To the extent that we raise additional capital through the sale of equity or convertible debt securities, the ownership interest of our stockholders will be or could be diluted, and the terms of these securities may include liquidation or other preferences that adversely affect the rights of our common stockholders. Debt financing and preferred equity financing, if available, may involve agreements that include covenants limiting or restricting our ability to take specific actions, such as incurring additional debt, making capital expenditures or declaring dividends. If we raise funds through collaborations, licenses and other similar arrangements with third parties, we may have to relinquish valuable rights to our technologies, future revenue streams, research programs or product candidates or grant licenses on terms that may not be favorable to us and/or may reduce the value of our common stock. Our failure to raise capital or enter into such other arrangements when needed could have a negative impact on our financial condition and on our ability to pursue our business plans and strategies. If we are unable to raise additional capital when needed, we could be forced to delay, limit, reduce or terminate our product candidate development or future commercialization efforts or grant rights to develop and market our product candidates even if we would otherwise prefer to develop and market such product candidates ourselves.

Recent Accounting Pronouncements

See Note 2 to our consolidated financial statements included elsewhere in this annual report.