Denali Therapeutics Inc. (DNLI) FY 2023 MD&A

ITEM 7.    MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

The following discussion and analysis of our financial condition and results of operations should be read together with our consolidated financial statements and the related notes to those statements included elsewhere in this report. This discussion and analysis and other parts of this report contain forward-looking statements based upon current beliefs, plans and expectations related to future events and our future financial performance that involve risks, uncertainties and assumptions, such as statements regarding our intentions, plans, objectives, expectations, forecasts and projections. Our actual results and the timing of selected events could differ materially from those anticipated in these forward-looking statements as a result of several factors, including those set forth under the section titled “Risk Factors” and elsewhere in this report.

Overview

Our goal is to discover, develop and deliver therapeutics to defeat degeneration.

Our discovery and development strategy is guided by three overarching principles that we believe will significantly increase the probability of success and accelerate the timing to bring effective therapeutics to people living with neurodegenerative diseases and LSDs:

•Degenogenes: Genetic Pathway Realization – each of our programs addresses a molecular target or biological pathway that is genetically validated to cause or increase the risk for neurodegenerative diseases.

•Brain Delivery: Validation and Optionality – we engineer our product candidates to cross the BBB and act directly in the brain. Our proprietary TV platform technology is designed to effectively deliver large therapeutic molecules, such as enzymes, proteins, antibodies, and oligonucleotides, across the BBB after intravenous administration.

•Biomarker-Driven Development and Approval – we discover, develop and use biomarkers to inform dose selection, assess clinical activity, and identify patients most likely to respond to our therapies. We are actively engaged in discussions with health authorities regarding the potential use of biomarkers as primary clinical endpoints to support faster paths to approval.

Our clinical-stage large molecule programs are as follows:

•Tividenofusp alfa (DNL310, ETV:IDS), our lead ERT program enabled by our ETV, ETV:IDS is designed to cross the BBB and restore IDS and reduce GAGs, both peripherally and in the brain, in patients with MPS II (Hunter syndrome);

•TAK-594/DNL593 (PTV:PGRN), our recombinant PGRN biotherapeutic enabled by our PTV, being developed in collaboration with Takeda, to address certain types of FTD, specifically FTD-GRN caused by PGRN deficiency;

•DNL126 (ETV:SGSH), our second most advanced ETV enabled program, which is designed to restore lysosomal activity of SGSH, an enzyme responsible for degrading heparan sulfates in the lysosome, in patients with MPS IIIA (Sanfilippo syndrome Type A).

Our clinical-stage small molecule programs are as follows:

•BIIB122/DNL151 (LRRK2), our LRRK2 inhibitor program, being developed in collaboration with Biogen, to address Parkinson’s disease;

•DNL343 (eIF2B), our eIF2B activator program to address diseases such as ALS and FTD;

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•SAR443820/DNL788 (CNS-penetrant RIPK1 inhibitor), our CNS-penetrant RIPK1 inhibitor program, partnered with Sanofi, to address neurological diseases such as MS and Alzheimer's disease; and

•Eclitasertib (SAR443122/DNL758, peripheral RIPK1 inhibitor), a second non-CNS penetrant RIPK1 inhibitor, partnered with Sanofi, to address peripheral inflammatory diseases such as UC.

The following table summarizes key information about our clinical stage programs:

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(1)Study has been voluntarily paused in order to implement protocol modifications and is expected to resume this year.

(2)Study will be closing as it did not meet its primary endpoint.

Since we commenced operations, we have devoted substantially all of our resources to discovering, acquiring and developing product candidates, building our BBB platform technology and assembling our core capabilities in understanding key neurodegenerative disease pathways.

Key operational and financing milestones for the year ended December 31, 2023 and in 2024 to date include:

•Tividenofusp alfa DNL310 (ETV:IDS)

◦In February 2023, at the WORLDSymposiumTM, we reported additional interim data from the open-label, single-arm Phase 1/2 study of DNL310. Over 49 weeks of DNL310 treatment in the Phase 1/2 study, positive changes across measures of exploratory clinical outcomes including VABS-II (adaptive behavior) and BSID-III (cognitive capabilities) scores and global impression scales were observed. The data also suggested that DNL310 improved hearing, as assessed by auditory brainstem response testing. Additional biomarker data out to 49 weeks continued to demonstrate that DNL310 enabled rapid and sustained normalization of cerebrospinal fluid ("CSF") heparan sulfate to normal healthy levels and improvement in lysosomal function biomarkers. Reduction in urine heparan sulfate and dermatan sulfate after switch from standard of care to DNL310 suggested additional sustained peripheral activity of DNL310. The DNL310 safety profile, with up to two years of treatment, remained consistent with standard of care;

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◦In June 2023, we announced a robust reduction in Neurofilament Light ("NfL") with DNL310 treatment in MPS II (Hunter syndrome). Interim results demonstrated average reduction of 64% (p 0.001) from baseline in serum NfL after two years of dosing with DNL310 in the Phase 1/2 study. The FDA has recommended assessment of NfL, a marker of neuroaxonal damage, as a possible biomarker in MPS II;

◦In August 2023, we presented new interim data from the Phase 1/2 study of DNL310 in MPS II in an oral presentation at the Society for the Study of Inborn Errors of Metabolism ("SSIEM") Annual Symposium 2023. The interim clinical outcomes data, safety profile, and biomarker effects, including normalization of CSF heparan sulfate and reduction in NfL, continue to support development of DNL310 in MPS II;

◦In January 2024, we announced that enrollment continues in the global Phase 2/3 COMPASS study and is expected to be completed in 2024. We continue to engage with the U.S. Food and Drug Administration on a faster path to approval; and

◦In February 2024, we presented additional interim data from the open-label, single-arm Phase 1/2 study of DNL310 at the 2024 WORLDSymposiumTM. Data out to 104 weeks showed additional improvement and stabilization in multiple measures of clinical outcomes, including those of adaptive behavior, cognition, hearing, and growth trajectory. In addition, robust and sustained responses in biomarkers of neuronal health (e.g., CSF heparan sulfate, neurofilament light (NfL)) and peripheral activity (e.g. urine heparan sulfate and dermatan sulfate) were observed. DNL310 continued to be generally well tolerated.

•TAK-594/DNL593 (PTV:PGRN)

◦In March 2023, a $10.0 million milestone payment from Takeda was triggered upon achievement of a specified clinical milestone in the Phase 1/2 study of TAK-594/DNL593 in patients with FTD-GRN, which we received in May 2023;

◦In July 2023, we presented healthy volunteer data from Part A of the Phase 1/2 study of TAK-594/DNL593 at the Alzheimer's Association International Conference, which continued to demonstrate that single doses of TAK-594/DNL593 resulted in substantial increases in CSF PGRN levels and were generally well tolerated; and

◦In January 2024, we announced that Part B in the TAK-594/DNL593 Phase 1/2 study in participants with FTD-GRN has been voluntarily paused to implement protocol modifications and is expected to resume this year.

•DNL126 (ETV:SGSH)

◦In February 2024, we announced that dosing had been initiated in the Phase 1/2 study of DNL126 in MPS IIIA; biomarker proof of concept and safety data are expected by the end of 2024. Further, in February 2024, we presented preclinical data at WORLDSymposiumTM demonstrating that DNL126 improves lysosomal and microglial morphology, degeneration, and cognitive behavior in MPS IIIA mice.

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•BIIB122/DNL151 (LRRK2)

◦In June 2023, in conjunction with Biogen, and based on review of portfolio timelines and resource prioritization, we announced plans to revise the clinical development program for BIIB122/DNL151. Prior to the planned revisions, the BIIB122 clinical development program encompassed two global late-stage clinical trials: the Phase 2b LUMA study in participants with early-stage Parkinson’s disease, which commenced in May 2022; and the Phase 3 LIGHTHOUSE study in participants with Parkinson’s disease related to LRRK2 mutations, which commenced in September 2022. In consideration of the LIGHTHOUSE study’s complexity, including the long timeline with anticipated study completion in 2031, Biogen and we plan to refocus our efforts to enable a timely readout on efficacy in idiopathic early-stage Parkinson’s disease while gaining further clinical data in Parkinson’s disease with and without a LRRK2 mutation. The planned revisions to the BIIB122 clinical development program are not based on any safety or efficacy data from studies of BIIB122. Biogen and we plan to modify the LUMA study’s enrollment criteria to allow for inclusion of eligible participants with Parkinson’s disease and a confirmed pathogenic variant of LRRK2, in addition to continuing to enroll eligible participants with idiopathic early-stage Parkinson’s disease. Collectively, data from the LUMA study will inform next steps for the development of BIIB122 in Parkinson’s disease;

◦In August 2023, we executed an amendment to the Definitive LRRK2 Collaboration and License Agreement and Waiver of and Amendment to Right of First Negotiation (ROFN), Option, and License Agreement. As part of the amendment, certain milestone criteria were changed while the total amount of development, regulatory, and commercial milestones across all indications remains the same. In addition, Biogen agreed to waive the remaining option and rights of first negotiation under the ROFN and Option Agreement; and

◦In February 2024, we announced the execution of a Collaboration and Development Funding Agreement in January 2024 with a third party related to a global Phase 2a study of BIIB122/DNL151, which we plan to solely operationalize to evaluate safety and biomarkers associated with BIIB122 in participants with Parkinson’s disease and confirmed pathogenic variants of LRRK2. This agreement includes committed funding of $75.0 million, of which $12.5 million was received in January 2024, and the remainder will be triggered based on time and operational milestones in the study. Biogen will continue to conduct the ongoing global Phase 2b LUMA study in early-stage Parkinson’s disease. Denali and Biogen will co-commercialize BIIB122/DNL151 assuming regulatory approval. The third party will be eligible to receive low single-digit royalties from Denali on annual worldwide net sales of LRRK2 inhibitors for the treatment of Parkinson’s disease, with royalty amounts varying based on the scope of the label.

•SAR443820/DNL788 and Eclitasertib (SAR443122/DNL758) (RIPK1)

◦In January 2023, our collaboration partner Sanofi commenced dosing in the Phase 2 study of SAR443820/DNL788 in patients with MS, triggering a $25.0 million milestone payment, which was received in January 2023. In November 2023 we announced that Sanofi has completed enrollment in this study;

◦In August 2023, we announced that Sanofi had completed enrollment in the global Phase 2 HIMALAYA study of SAR443820/DNL788 in ALS in July;

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◦In August 2023, we announced that Sanofi completed a Phase 2 study of eclitasertib, also known as SAR443122/DNL758, in patients with CLE in June. In October 2023, Sanofi announced that the development of eclitasertib in CLE is being discontinued because the Phase 2 proof-of-concept study did not meet its primary endpoint (percent change from baseline in CLASI-A at week 12). Eclitasertib was found to be generally well-tolerated. Sanofi continues to recruit the Phase 2 study of eclitasertib in patients with UC; and

◦In February 2024, we announced that the Phase 2 HIMALAYA study evaluating SAR443820/DNL788 in participants with ALS did not meet the primary endpoint of change in ALS Functional Rating Scale-Revised (ALSFRS-R). Sanofi intends to present the detailed efficacy and safety results of the ALS Phase 2 HIMALAYA study at a future scientific forum. Sanofi is evaluating SAR443820/DNL788 in another Phase 2 clinical trial in participants with MS, and the outcome of HIMALAYA study has no impact on the ongoing MS study.

•DNL343 (eIF2B)

◦In April 2023, we presented final data from the 28-day treatment period of the Phase 1b study of DNL343 in participants with ALS at the 75th Annual Meeting of the American Academy of Neurology ("AAN"). The results continued to demonstrate that once-daily oral dosing with DNL343 for 28 days was generally well tolerated and demonstrated extensive CSF penetration. In addition, robust inhibition of biomarkers associated with the ISR pathway was observed in blood samples from study participants; and

◦In May 2023, the first patient was dosed with DNL343 in the Phase 2/3 HEALEY ALS Platform Trial. Recruitment of participants continues for this trial.

•Other

◦In March 2023, a contingent consideration payment of $30.0 million associated with our acquisition of F-star Gamma was triggered upon the achievement of a specified clinical milestone in the ETV:IDS program. This payment fully satisfies our clinical contingent consideration obligations under the Purchase Agreement;

◦In April 2023, we entered into a new operating lease in Salt Lake City, Utah for a 59,336 square foot laboratory (the "Utah site"), office and warehouse premises, after terminating our previous SLC lease in March 2023, decreasing future lease payments by $6.1 million while increasing the lease term by approximately five and a half years. The Utah site will expand our clinical manufacturing capabilities for biologic therapeutics (large molecules) as we plan to use the premises for the manufacture of materials for toxicology studies and drug substance for early human clinical studies with the goal of increasing flexibility and speed in advancing new investigational therapies into clinical trials;

◦In April 2023, our collaboration partner Biogen exercised its option to develop and commercialize our ATV program targeting amyloid-beta, triggering an option exercise payment of $5.0 million, which we received in May 2023;

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◦In August 2023 we announced that, in agreement with Takeda, the companies will discontinue clinical development of TAK-920/DNL919 in Alzheimer’s disease. This is a strategic decision based on the totality of clinical data emerging from the single ascending dose Phase 1 study of TAK-920/DNL919 in healthy volunteers and in consideration of the rapidly evolving treatment landscape for Alzheimer's disease whereby an understanding of drug combinations with newly approved therapies will be important. A preliminary analysis of Phase 1 data indicates robust target engagement and effects on microglial biomarkers (e.g., CSF1R, SPP1, IL1RA, IP10, MIP1b, MCP-1), which were consistent with preclinical studies that demonstrate that ATV:TREM2 induces robust changes to a responsive microglial cell state (van Lengerich B, et al. Nat Neurosci. 2023). In the Phase 1 study, TAK-920/DNL919 was clinically well tolerated at doses with demonstrated changes in CSF biomarkers and there were no serious adverse events or severe treatment emergent adverse events; however, safety signals of moderate, reversible hematologic effects were observed at the highest dose tested, suggesting a narrow therapeutic window for the Alzheimer’s disease patient population. The Phase 1 safety findings are believed to be specific to properties of TAK-920/DNL919 and TREM2 biology. Denali and Takeda will continue to focus research efforts on back-up molecules in preclinical development, including exploration of potential combination therapy given recent new drug approvals in Alzheimer's disease;

◦In January 2024, we announced our intention to spin out our preclinical small molecule portfolio. We will maintain ownership of, and continue to advance, our current portfolio of clinical stage small molecule programs. The decision was made based on clinical validation and prioritization of our TV-enabled platforms for brain delivery of large molecules; and

◦In February 2024, we announced that on February 27, 2024 we entered into a securities purchase agreement with certain existing accredited investors for the private placement of 3,244,689 shares of our common stock at a price of $17.07 per share and pre-funded warrants to purchase an aggregate of 26,046,065 shares of our common stock at a purchase price of $17.06 per pre-funded warrant, resulting in anticipated gross proceeds of approximately $499.7 million. The pre-funded warrants will have an exercise price of $0.01 per share of Common Stock, be immediately exercisable and remain exercisable until exercised in full. The private placement is expected to close on February 29, 2024, subject to customary closing conditions.

We do not have any products approved for sale and have not generated any product revenue since our inception. We have funded our operations primarily from the issuance and sale of convertible preferred stock, the sale of common stock in public offerings, and payments received from our collaboration agreements with Takeda, Sanofi and Biogen.

We have incurred significant operating losses to date and expect to continue to incur operating losses for the foreseeable future. Our ability to generate product revenue will depend on the successful development and eventual commercialization of one or more of our product candidates. We had net losses of $145.2 million, $326.0 million, and $290.6 million for the years ended December 31, 2023, 2022, and 2021, respectively. As of December 31, 2023, we had an accumulated deficit of $1.12 billion. We expect to continue to incur significant expenses and operating losses as we advance our current clinical stage programs through healthy volunteer and patient trials; broaden and improve our BBB platform technology; acquire, discover, validate and develop additional product candidates; obtain, maintain, protect and enforce our intellectual property portfolio; and hire additional personnel.

We currently rely on third-party contract manufacturers to manufacture and supply our preclinical and clinical materials to be used during the development of our product candidates. We currently do not need commercial manufacturing capacity.

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License and Collaboration Agreements

Collaborations and partnering are central components of our strategy to build, develop and commercialize our portfolio of product candidates. We have numerous arrangements with biopharmaceutical companies, technology companies, academic institutions, foundations, and patient-focused data companies.

Biogen

In October 2020, we entered into the LRRK2 Agreement with Biogen pursuant to which we granted Biogen a license to co-develop and co-commercialize our small molecule LRRK2 Program, in addition to the ROFN and Option Agreement pursuant to which we granted an option and a right of first negotiation to certain of our programs utilizing our TV technology platform; collectively the "Biogen Collaboration Agreement." In connection with our collaboration with Biogen, we also entered into a common stock purchase agreement pursuant to which we sold 13,310,243 shares of our common stock to BIMA for an aggregate purchase price of $465.0 million. Under the terms of the Biogen Collaboration Agreement, we received $560.0 million in upfront payments in October 2020.

In April 2023, Biogen exercised its option to license our ATV:Abeta program and we received additional consideration of $5.0 million for an option exercise fee. In August 2023, we executed an Amendment (the “Biogen Amendment”) to the LRRK2 Agreement and ROFN and Option Agreement with Biogen. Pursuant to the Biogen Amendment, the schedule of potential LRRK2 Agreement milestones was amended, while maintaining the same total value of milestones that Denali is eligible to receive. In addition, Biogen waived its option right to the second option program and waived its rights of first negotiation for two other TV-enabled programs under the ROFN and Option Agreement. Further details regarding the terms of the agreements between us and Biogen are included in this Annual Report on Form 10-K in the section titled "Business - Licenses and Collaborations."

In relation to the Biogen Collaboration Agreement, we have recognized related party collaboration revenue of $295.5 million, $3.1 million, and $3.7 million in the years ended December 31, 2023, 2022 and 2021, respectively, related party research and development expense of $17.7 million and $8.2 million for cost sharing payments to Biogen in the year ended December 31, 2023 and 2022, respectively, and a related party offset to research and development expense as a result of cost sharing reimbursements from Biogen of $6.5 million in the year ended December 31, 2021. We have recorded cost sharing payables of $3.2 million and $4.4 million on the Consolidated Balance Sheet as of December 31, 2023 and 2022, respectively. Through December 31, 2023, we had earned $5.0 million in option fee payments but had not recorded any milestone revenue or product sales under the Biogen Collaboration Agreement.

Sanofi

In October 2018, we entered into the Sanofi Collaboration Agreement with Sanofi pursuant to which certain small molecule CNS and peripheral RIPK1 inhibitors contributed by Sanofi and by us are being, or will be developed and commercialized. Further details regarding the terms of the agreement between us and Sanofi, and historic payments between the parties under the agreement, are included in this Annual Report on Form 10-K in the section titled "Business - Licenses and Collaborations."

We have recognized collaboration revenue of $25.0 million, $53.4 million and $15.0 million associated with the Sanofi Collaboration Agreement in the years ended December 31, 2023, 2022 and 2021, respectively, and recorded no receivable from Sanofi on the Consolidated Balance Sheets as of December 31, 2023 and 2022. Through December 31, 2023, we had received milestone payments of $100.0 million and we had not recorded any product sales under the Sanofi Collaboration Agreement.

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Takeda

In January 2018, we entered into the Takeda Collaboration Agreement pursuant to which we granted Takeda an option to develop and commercialize, jointly with us, our ATV:TREM2, PTV:PGRN and ATV:BACE1/Tau programs, the latter of which was later replaced with our ATV:Tau program. Pursuant to the terms of the Takeda Collaboration Agreement, we also entered into the Purchase Agreement with Takeda in January 2018, pursuant to which we sold 4,214,559 shares of our common stock to Takeda for an aggregate purchase price of $110.0 million.

In November 2021 and December 2021, Takeda exercised its options for the PTV:PGRN and ATV:TREM2 programs, respectively, subsequent to which we have shared equally in the development costs for the programs. In March 2022, we mutually agreed under the Takeda Collaboration Agreement to terminate activity on the ATV:Tau program. Further details regarding the terms of the agreement between us and Takeda, and historic payments between the parties under the agreements, are included in this Annual Report on Form 10-K in the section titled "Business - Licenses and Collaborations."

We recognized collaboration revenue of $10.0 million, $51.9 million and $29.9 million associated with the Takeda Collaboration Agreement in the years ended December 31, 2023, 2022 and 2021, respectively, and offsets to research and development expense for cost sharing reimbursements of $12.2 million, $18.2 million and $13.7 million in the years ended December 31, 2023, 2022, and 2021, respectively. We recorded receivables of $2.7 million and $8.9 million from Takeda as of December 31, 2023 and 2022, respectively. Through December 31, 2023, we have received $65.0 million in milestone payments and $10.0 million of option exercise fees from Takeda, and we have not recorded any product sales under the Takeda Collaboration Agreement.

F-star

In August 2016, we entered into the F-star Collaboration Agreement with the F-star entities. The goal of the collaboration was the development of Fcabs to enhance delivery of therapeutics across the BBB into the brain. In connection with the entry into the F-star Collaboration Agreement, we also purchased an option to acquire all of the outstanding shares of F-star Gamma pursuant to a pre-negotiated buy-out option agreement. In May 2018, we exercised such buy-out option and entered into the F-star Purchase Agreement with the shareholders of F-star Gamma and Shareholder Representative Services LLC, pursuant to which we acquired all of the outstanding shares of F-star Gamma. As a result of the Acquisition, F-star Gamma became our wholly-owned subsidiary and the entity's name was changed to Denali BBB Holding Limited. In addition, we became a direct licensee of certain intellectual property of F-star Ltd by way of our assumption of F-star Gamma’s license agreement with F-star Ltd, dated August 24, 2016. Further details regarding the terms of the arrangements between us and the F-star entities, and historic payments between the parties under the agreements, are included in this Annual Report on Form 10-K in the section titled "Business - Licenses and Collaborations."

Through December 31, 2023 we have recognized consideration paid under the F-star Purchase Agreement of $49.8 million as research and development expenses consisting of up-front, preclinical and clinical contingent consideration payments, of which $30.0 million of research and development expense was recognized in the year ended December 31, 2023 for a contingent consideration payment triggered in March 2023 upon the achievement of a specified clinical milestone in the ETV:IDS program. There was no contingent consideration research and development expense recognized in the years ended December 31, 2022 or 2021. We recognized $0.1 million of research and development expense related to the funding of F-star research costs for the year ended December 31, 2021, but none for the years ended December 31, 2023 or 2022.

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Genentech

In June 2016, we entered into an exclusive license agreement with Genentech. The agreement gives us access to Genentech’s LRRK2 inhibitor program. Our collaboration partner in the LRRK2 program, Biogen, is responsible for 50% of any payment obligation to Genentech under the Biogen Collaboration Agreement.

As consideration to date, we have paid Genentech $25.0 million in the aggregate, including an upfront fee, a technology transfer fee and three clinical milestone payments, with $18.8 million of this recorded as research and development expense as incurred, net of cost sharing reimbursements from Biogen. Included within this amount, in the year ended December 31, 2022, we paid Genentech a $7.5 million clinical milestone payment triggered upon the commencement of dosing in the global Phase 2b LUMA study to evaluate the efficacy and safety of BIIB122/DNL151 by Biogen, and a further $5.0 million clinical milestone payment triggered upon the commencement of dosing in the global Phase 3 LIGHTHOUSE study to evaluate the efficacy and safety profile of BIIB122/DNL151 by Biogen. Of these milestones, we recognized $6.3 million as research and development expense as incurred after cost sharing reimbursements from Biogen in the year ended December 31, 2022. We recognized no expenses under this agreement in the years ended December 31, 2023 and 2021.

Components of Operating Results

Collaboration Revenue

To date, we have not generated any revenue from product sales and do not expect to generate any revenue from product sales for the foreseeable future. All revenue recognized to date has been collaboration and license revenue from our collaboration agreements with Takeda, Sanofi and Biogen.

Future revenue may be recognized from the Takeda Collaboration Agreement, Sanofi Collaboration Agreement, and Biogen Collaboration Agreement, and may be generated from product sales or milestone payments, royalties and profit sharing reimbursement from other collaboration agreements, strategic alliances and licensing arrangements. We expect that our revenue will fluctuate from quarter-to-quarter and year-to-year as a result of the timing and amount of license fees, option exercise fees, milestone payments, profit sharing reimbursement, other payments and product sales, to the extent any are successfully commercialized. If we fail to complete the development of our product candidates in a timely manner or obtain regulatory approval for them, our ability to generate future revenue, and our results of operations and financial position, would be materially adversely affected.

Operating Expenses

Research and Development

Research and development activities account for a significant portion of our operating expenses. We record research and development expenses as incurred. Research and development expenses incurred by us for the discovery and development of our product candidates and BBB platform technology include:

• external research and development expenses, including:

–expenses incurred under arrangements with third parties, such as contract research organizations ("CROs"), preclinical testing organizations, contract development and manufacturing organizations ("CDMOs"), academic and non-profit institutions and consultants;

–expenses to acquire technologies to be used in research and development that have not reached technological feasibility and have no alternative future use;

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–fees related to our license and collaboration agreements;

•personnel related expenses, including salaries, benefits and stock-based compensation expense; and

•other expenses, which include direct and allocated expenses for laboratory, facilities and other costs.

A portion of our research and development expenses are direct external expenses, which we track on a program-specific basis once a program has commenced late-stage IND-enabling studies.

Program expenses include expenses associated with our most advanced product candidates and the discovery and development of backup or next-generation molecules. We also track external expenses associated with our TV platform. These expenses include external expenses incurred by us relating to our Takeda Collaboration Agreement, Sanofi Collaboration Agreement and Biogen Collaboration Agreement. All external costs associated with earlier stage programs, or that benefit the entire portfolio, are tracked as a group. We also incur personnel and other operating expenses for our research and development programs which are presented in aggregate. These expenses primarily relate to salaries and benefits, stock-based compensation, facility expenses including rent and depreciation, and lab consumables. Where we share costs with our collaboration partners, such as in our Biogen Collaboration Agreement and Takeda Collaboration Agreement, research and development expenses may include cost sharing reimbursements from, or payments to, our collaboration partners.

It is challenging to predict the nature, timing and estimated long-range costs of the efforts that will be necessary to complete the development of, and obtain regulatory approval for, any of our product candidates. This is made more challenging by events outside of our control, such as the COVID-19 pandemic and increased geopolitical uncertainty. We are also unable to predict when, if ever, material net cash inflows will commence from sales or licensing of our product candidates. This is due to the numerous risks and uncertainties associated with drug development, including the uncertainty of:

•our ability to add and retain key research and development personnel;

•our ability to establish an appropriate safety profile with IND-enabling toxicology studies;

•our ability to successfully develop, obtain regulatory approval for, and then successfully commercialize, our product candidates;

•our successful enrollment in and completion of clinical trials;

•the costs associated with the development of any additional product candidates we identify in-house or acquire through collaborations;

•our ability to discover, develop and utilize biomarkers to demonstrate target engagement, pathway engagement and the impact on disease progression of our molecules;

•our ability to establish agreements with third-party manufacturers for clinical supply for our clinical trials and commercial manufacturing, if our product candidates are approved;

•the terms and timing of any collaboration, license or other arrangement, including the terms and timing of any milestone payments thereunder;

•our ability to obtain and maintain patent, trade secret and other intellectual property protection and regulatory exclusivity for our product candidates if and when approved;

•our receipt of marketing approvals from applicable regulatory authorities;

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•our ability to commercialize products, if and when approved, whether alone or in collaboration with others; and

•the continued acceptable safety profiles of the product candidates following approval.

A change in any of these variables with respect to the development of any of our product candidates would significantly change the costs, timing and viability associated with the development of that product candidate. We expect our research and development expenses to increase at least over the next several years as we continue to implement our business strategy, advance our current programs, expand our research and development efforts, seek regulatory approvals for any product candidates that successfully complete clinical trials, access and develop additional product candidates and incur expenses associated with hiring additional personnel to support our research and development efforts. In addition, product candidates in later stages of clinical development generally incur higher development costs than those in earlier stages of clinical development, primarily due to the increased size and duration of later-stage clinical trials.

General and Administrative

General and administrative expenses include personnel related expenses, such as salaries, benefits, travel and stock-based compensation expense, expenses for outside professional services and allocated expenses. Outside professional services consist of legal, accounting and audit services and other consulting fees. Allocated expenses consist of rent, depreciation and other expenses related to our office and research and development facility not otherwise included in research and development expenses. We expect to increase our administrative headcount as we advance our product candidates through clinical development, which will increase our general and administrative expenses.

Interest and Other Income, Net

Interest and other income, net, consists primarily of interest income and investment income earned on our cash, cash equivalents, and marketable securities, and sublease income.

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Results of Operations

Comparison of the years ended December 31, 2023 and 2022

The following table sets forth the significant components of our results of operations (in thousands):

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*Percentage is not meaningful.

Collaboration revenue. Collaboration revenue was $330.5 million for the year ended December 31, 2023 compared to $108.5 million for the year ended December 31, 2022. The increase in collaboration revenue of $222.0 million was primarily due to $293.9 million in revenue recognized in April 2023 under the Biogen Collaboration Agreement as a result of Biogen exercising its option to license our ATV:Abeta program, partially offset by a decrease of $41.9 million in revenue earned under the Takeda Collaboration Agreement, as well as a decrease of $28.4 million in milestone revenue earned under the Sanofi Collaboration Agreement. The decreases in revenues from the Sanofi and Takeda Collaboration Agreements are due to the timing of underlying activities and achievement of milestones under the collaboration agreements.

Research and development expenses. Research and development expenses were $423.9 million for the year ended December 31, 2023 compared to $358.7 million for the year ended December 31, 2022.

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The following table summarizes our research and development expenses by program and category (in thousands):

_________________________________________________

*Percentage is not meaningful.

(1)Personnel-related expenses include stock-based compensation expense of $62.9 million and $60.2 million for the years ended December 31, 2023 and 2022, respectively, reflecting an increase of $2.7 million.

(2)Net cost sharing payments (reimbursements) details are broken down as shown in the table below. The underlying costs for reimbursements are included with the specified external expenses line and personnel related expenses in the table above. ATV:TREM2 program external expenses are presented within the TV platform and other program external expenses line.

The increase in research and development expenses of approximately $65.2 million for the year ended December 31, 2023 compared to the year ended December 31, 2022 was primarily attributable to the following:

•An increase of $53.2 million in ETV:IDS program external expenses primarily due to the contingent consideration payment of $30.0 million recorded in the first quarter of 2023 related to the acquisition of F-star Gamma, which was triggered in March 2023 upon the achievement of a specified clinical milestone in the ETV:IDS program. Further, the increase reflects the continued progress of this program in clinical trials during 2023, including costs related to our ongoing Phase 1/2 study and our potentially registrational Phase 2/3 study;

•An increase of $9.6 million in eIF2B program external expenses reflecting the continued progress of the Phase 2/3 HEALEY ALS Platform Trial in 2023;

•An increase of $15.6 million in net cost sharing payments primarily due to an increase in payments to Biogen for LRRK2 program expenses, and a decrease in costs and associated reimbursements from Takeda in the PTV:PGRN and ATV:TREM2 programs;

•An increase of $9.3 million in other unallocated research and development expenses primarily due to increased facility costs as a result of accelerated depreciation on leasehold improvements associated with the termination of the previous SLC Lease as well as other general research costs;

•An increase of $16.4 million in personnel-related expenses, consisting of $13.7 million in employee compensation and $2.7 million in stock-based compensation expense in stock-based compensation expense pertaining to additional salaries, related expenses, and equity award grants driven by an increase in our research and development headcount.

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These increases were partially offset by decreases of $14.2 million in LRRK2 program external expenses due to the transition of LRRK2 clinical activities to Biogen, $10.5 million in TV platform and other program external expenses as a result of discontinuation of clinical development of TAK-920/DNL919, and $7.0 million in other external research and development expenses and $7.2 million in PTV:PGRN program external expenses due to the timing of significant external research and manufacturing related activities year over year.

General and administrative expenses. General and administrative expenses were $103.4 million for the year ended December 31, 2023 compared to $90.5 million for the year ended December 31, 2022. The increase of $12.9 million was primarily attributable to the following:

•An increase of $9.5 million of personnel-related expenses consisting of employee compensation and stock-based compensation expense associated with additional salary expenses and equity award grants driven primarily by higher general and administrative headcount;

•An increase of $3.4 million in professional services, facilities and other corporate costs.

Comparison of the years ended December 31, 2022 and 2021

Refer to “Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations—Results of Operations” in our 2022 Annual Report on Form 10-K for a discussion of the results of operations for the year ended December 31, 2022 compared to the year ended December 31, 2021.

Liquidity and Capital Resources

Sources of Liquidity

As of December 31, 2023, we had cash, cash equivalents and marketable securities in the amount of $1.03 billion. We fund our operations primarily with the proceeds from the sale of common stock and payments received from collaboration partners, including those received under agreements with Takeda, Sanofi, and Biogen. We have sold common stock in public offerings and stock purchase agreements with Takeda and Biogen. Through December 31, 2023 we have obtained aggregate net proceeds of approximately $754.4 million from public offerings of our common stock, including $296.2 million obtained through the sale of 11.9 million shares of common stock in October 2022. Under stock purchase agreements with collaboration partners we have received a further $575.0 million through December 31, 2023.

In February 2022, we established a registered “at-the-market” facility for the sale of up to 400.0 million of shares of common stock from time to time by entering into an equity distribution agreement with Goldman Sachs & Co. LLC, SVB Securities LLC and Cantor Fitzgerald & Co. as sales agents. To date, no shares have been sold under the equity distribution agreement.

Pursuant to our collaboration agreements with Takeda, Sanofi and Biogen, through December 31, 2023 we have received upfront, option and milestone payments of $115.0 million, $225.0 million, and $560.0 million, respectively, and have also received $41.3 million and $16.2 million of gross cost sharing reimbursements from Takeda and Biogen, respectively, and $13.7 million in specified reimbursements from Sanofi.

Future Funding Requirements and Commitments

To date, we have not generated any product revenue. We do not expect to generate any product revenue unless and until we obtain regulatory approval of and commercialize any of our product candidates, and we do not know when, or if, either will occur.

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We expect to continue to incur significant losses for the foreseeable future, and we expect the losses to increase as we expand our research and development activities and continue the development of, and seek regulatory approvals for, our product candidates, and begin to commercialize any approved products. Further, we expect general and administrative expenses to increase as we continue to incur additional costs associated with supporting our growing operations. We are subject to all of the risks typically related to the development of new product candidates, and we may encounter unforeseen expenses, difficulties, complications, delays and other unknown factors that may adversely affect our business. We anticipate that we will need substantial additional funding in connection with our continuing operations.

Until we can generate a sufficient amount of revenue from the commercialization of our product candidates or from our existing collaboration agreements, or future agreements with other third parties, if ever, we expect to finance our future cash needs through public or private equity or debt financings. Additional capital may not be available on reasonable terms, if at all. If we are unable to raise additional capital in sufficient amounts or on terms acceptable to us, we may have to significantly delay, scale back or discontinue the development or commercialization of one or more of our product candidates. If we raise additional funds through the issuance of additional debt or equity securities, it could result in dilution to our existing stockholders, increased fixed payment obligations and the existence of securities with rights that may be senior to those of our common stock. If we incur indebtedness, we could become subject to covenants that would restrict our operations and potentially impair our competitiveness, such as limitations on our ability to incur additional debt, limitations on our ability to acquire, sell or license intellectual property rights and other operating restrictions that could adversely impact our ability to conduct our business. Additionally, any future collaborations we enter into with third parties may provide capital in the near term but limit our potential cash flow and revenue in the future. Any of the foregoing could significantly harm our business, financial condition and prospects.

Since our inception, we have incurred significant losses and negative cash flows from operations. We have an accumulated deficit of $1.12 billion through December 31, 2023. We expect to incur substantial additional losses in the future as we conduct and expand our research and development activities. We believe that our existing cash, cash equivalents and marketable securities will be sufficient to enable us to fund our projected operations through at least the twelve months following the filing date of this Form 10-K, including our existing commitments as outlined below. We have based this estimate on assumptions that may prove to be wrong, and we could utilize our available capital resources sooner than we currently expect. In the longer term, we anticipate that we will need substantial additional resources to fund our operations and meet future commitments.

Our existing commitments primarily relate to our obligations under existing lease agreements, and certain clinical and manufacturing agreements, including the DMSA with Lonza Sales AG ("Lonza") for the development and manufacture of biologic products. As of December 31, 2023, operating lease liabilities were $52.2 million. Under the SLC lease which was executed in April 2023, we have future undiscounted lease payments totaling approximately $13.4 million. Under the DMSA with Lonza, and certain other clinical and manufacturing agreements, we had total non-refundable purchase commitments of $74.0 million as of December 31, 2023, with certain amounts subject to cost sharing with Takeda. Further, in the normal course of business, we enter into various firm purchase commitments primarily related to research and development activities. While the lease obligations span multiple years, the majority of the purchase commitments with Lonza and other clinical and manufacturing agreements are due within twelve months, with some spanning several years. These commitments are more fully described in Note 8, "Commitments and Contingencies" to the consolidated financial statements included in Item 8. of this Annual Report on Form 10-K.

Our future funding requirements, including changes to and new commitments, will depend on many factors, including:

•the timing and progress of preclinical and clinical development activities;

•the number and scope of preclinical and clinical programs we decide to pursue;

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•the progress of the development efforts of third parties with whom we have entered into license and collaboration agreements;

•our ability to maintain our current research and development programs and to establish new research and development, license or collaboration arrangements;

•our ability and success in securing manufacturing relationships with third parties or in establishing and operating a manufacturing facility;

•the costs involved in prosecuting, defending and enforcing patent claims and other intellectual property claims;

•the cost and timing of regulatory approvals;

•our efforts to enhance operational, financial and information management systems and hire additional personnel, including personnel to support development of our product candidates; and

•the costs and ongoing investments to in-license and/or acquire additional technologies.

A change in the outcome of any of these or other variables with respect to the development of any of our product candidates could significantly change the costs and timing associated with the development of that product candidate. Furthermore, our operating plans may change in the future, and we may need additional funds to meet operational needs and capital requirements associated with such operating plans.

Cash Flows

The following table sets forth a summary of the primary sources and uses of cash for each of the periods presented below (in thousands):

Net Cash Used In Operating Activities

During the year ended December 31, 2023, net cash used in operating activities was $358.0 million, which consisted of a net loss of $145.2 million, adjusted by non-cash items primarily related to stock-based compensation expense, depreciation and amortization, net amortization of premiums and (discounts) on marketable securities and non-cash rent expenses. Cash used in operating activities was also driven by changes in our operating assets and liabilities, the most significant of which was the reduction in our related-party contract liability as a result of Biogen's option exercise during the second quarter of 2023.

Net Cash Provided By (Used In) Investing Activities

During the year ended December 31, 2023, net cash provided by investing activities was $249.3 million, which consisted of $2.1 billion in proceeds from the maturities and sales of marketable securities, partially offset by $1.8 billion of purchases of marketable securities, and $12.9 million capital expenditures to purchase property and equipment.

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Net Cash Provided By Financing Activities

During the year ended December 31, 2023, net cash provided by financing activities was $17.8 million, which consisted of proceeds from the exercise of options to purchase common stock and purchases of ESPP shares.

Years ended December 31, 2022 and 2021

Refer to “Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations—Liquidity and Capital Resources” in our 2022 Annual Report on Form 10-K for a discussion of the cash flows for the years ended December 31, 2022 and 2021.

Critical Accounting Estimates

This discussion and analysis of our financial condition and results of operations is based on our consolidated financial statements, which have been prepared in accordance with U.S. GAAP. The preparation of these consolidated financial statements requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements, as well as the reported revenues recognized and expenses incurred during the reporting periods. Our estimates are based on our historical experience and on various other factors that we believe are reasonable under the circumstances, the results of which form the basis for making judgments about the carrying value of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these estimates under different assumptions or conditions. Our significant accounting policies are described in detail in the notes to our consolidated financial statements included elsewhere in this report. We believe that the following accounting estimates involve a significant level of estimation uncertainty which could have a material impact on our financial condition or results of operations.

Revenue Recognition

We recognize revenue associated with our collaboration arrangements, which may require us to exercise considerable judgment in estimating revenue to be recognized, including judgments made on day one accounting and judgments associated with the amount of revenue to be recognized over time as performance obligations are satisfied.

Significant judgment is required to apply the authoritative accounting guidance at the outset of a collaboration arrangement, and over time, as detailed below:

•Identification of performance obligations - there is judgment involved in identifying the promised goods or services in the collaboration agreement, determining whether these are distinct in the context of the contract, and determining if these represent a performance obligation to a customer. These determinations are highly subjective and can differ between arrangement based on specific contractual terms. The identified performance obligations will impact most significantly the timing of revenue recognition, and is a point-in-time assessment performed at the outset of a collaboration arrangement.

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•Measurement of the transaction price - determining the transaction price includes varying levels of judgment. Where amounts are fixed and paid, such as upfront payments, estimation is not required. However, other elements of the transaction price do require estimation or assumptions by management. The calculation of a share issuance premium requires the use of a valuation model for purposes of determining the fair value of the shares for financial reporting purposes, with any resulting premium impacting the transaction price. An assumption needs to be made regarding whether future variable consideration, such as milestone payments, are constrained, which also requires management judgment. The measurement of transaction price impacts the measurement of revenue, and is performed both at the outset of a collaboration arrangement and at each reporting period. To date, we have not recognized any adjustments to revenue as a result of an adjustment to variable consideration constraint.

•Allocation of the transaction price to the performance obligations - there is significant judgment required to allocate the transaction price to performance obligations. Generally, this is done by estimating the standalone selling price of identified performance obligations, and allocating on a relative value basis. The estimate of standalone selling price includes several assumptions that cannot be observed, which may include forecasted revenue (for products not yet on the market), development timelines, reimbursement rates for personnel costs, discount rates and probabilities of technical and regulatory success. The standalone selling price of performance obligations can be very sensitive to many of these underlying assumptions, which are based on management estimates since they cannot be observed. This is a point-in-time assessment performed at the outset of a collaboration arrangement.

•Recognition of revenue when (or as) we satisfy each performance obligation - determining the timing of revenue recognition includes varying levels of judgment. For revenue types recognized at a point in time, such as functional IP, there can be some judgment as to when the performance obligation has been satisfied. For revenue recognized over time, this is often based on an underlying measure deemed to approximate the progress towards satisfaction of performance obligations. These underlying measures, such as costs incurred to date compared with total forecasted costs for a service, may include inherent estimates, which in turn can impact the timing of revenue recognition. The satisfaction of performance obligations assessment is performed at each reporting period. To date, there have been no material true ups to revenue as a result of changes in the satisfaction of performance obligations.

Research and Development Expenses

A significant portion of our research and development expenses in the Consolidated Statements of Operations and Comprehensive Loss are external costs, which we track on a program-specific basis once a program has commenced a late-stage IND-enabling study. These research and development expenses include the conduct of preclinical studies and clinical trials, contract manufacturing activities and consulting services. The measurement of these research and development expenses can impact the measurement of research and development expenses in the Consolidated Statements of Operations and Comprehensive Loss, and of prepaid assets and accrued liabilities on the Consolidated Balance Sheets.

The level of judgment required to estimate research and development expenses varies based on the nature of the services being performed and the underlying support obtained. We estimate the amount of work completed through discussions with internal personnel and external service providers as to the progress or stage of completion of the services and the agreed-upon fee to be paid for such services. As actual costs become known, we adjust our accrued estimates. Although we do not expect our estimates to be materially different from amounts actually incurred, incomplete or inaccurate data from vendors could impact our understanding of the status and timing of services performed which could result in us reporting expenses that are too high or too low in any particular period.

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In some cases, expense is recorded using an underlying assumption of the progress to completion of specific activities. For example, costs may be recognized based on the passage of time for activities that span reporting periods. If the provision of services is not linear then this assumption could impact the amount of expense recognized. For other activities, such as for certain clinical trials, expense is recorded based on information obtained from vendors as an intermediary to those performing the underlying services, such as contract research organizations. These estimates are inherently more judgmental since the quality and availability of the underlying data may vary. To date, there have been no material true ups from estimated to actual external research and development expenses. However, we expect that the level of judgment in estimating research and development expenses may increase over time as we are entering later stage, more extensive, clinical trials.

Research and development expenses also include reimbursements owed or owing to a collaboration partner to satisfy cost sharing requirements. These reimbursement amounts are estimated based, in part, on data received from our collaboration partner, which may include a certain level of estimation or judgments made by that partner. They also reflect our estimates of research and development expense as discussed above. As such, a change in estimates or judgments by either our partner or us can result in a change to a reimbursement amount. To date, there have been no material true ups from estimated to actual reimbursements owed or owing.

Recent Accounting Pronouncements

See Note 1 to our consolidated financial statements included in Part II, Item 8, “Financial Statements and Supplementary Data,” of this Annual Report on Form 10-K for a description of recent accounting pronouncements applicable to our business.