Dianthus Therapeutics, Inc. /DE/ (DNTH)

CIK: 0001690585. SIC: 2834 Pharmaceutical Preparations. Latest 10-K as of: 2026-03-09.

SIC breadcrumb: Manufacturing > Chemicals And Allied Products > SIC 2834 Pharmaceutical Preparations

SEC company page: https://www.sec.gov/edgar/browse/?CIK=1690585. Latest filing source: 0001690585-26-000006.

Selected Fundamentals

Financials

Annual standardized facts from SEC companyfacts as of latest extracted filing date 2026-03-09. Source: https://data.sec.gov/api/xbrl/companyfacts/CIK0001690585.json. Derived margins, ratios, and free cash flow are computed from the extracted annual SEC facts.

Flow metrics use full-year FY periods from 10-K/10-K/A filings; balance-sheet metrics use FY-end instants. Free cash flow = operating cash flow - capital expenditures. Missing metrics are omitted rather than fabricated.

Ratios

ROE and ROA use period-end equity/assets. Liabilities / equity uses total liabilities divided by stockholders' equity. Current ratio uses current assets divided by current liabilities when both are reported.

Financial Charts

Quarterly

Quarterly standardized facts from SEC companyfacts as of latest extracted filing date 2026-05-05. Source: https://data.sec.gov/api/xbrl/companyfacts/CIK0001690585.json.

Flow metrics use discrete quarter-length periods from 10-Q/10-Q/A filings. Q4 revenue and net income are derived only when annual FY and nine-month YTD facts exist for the same fiscal year; derived Q4 values are labeled. EPS Q4 is not derived.

Quarterly Charts

Macro Cross-References

• CPIAUCSL - Consumer Price Index for All Urban Consumers: All Items in U.S. City Average
• UNRATE - Unemployment Rate
• FEDFUNDS - Federal Funds Effective Rate
• CES0500000003 - Average Hourly Earnings of All Employees, Total Private
• DFEDTARU - Federal Funds Target Range - Upper Limit
• DFEDTARL - Federal Funds Target Range - Lower Limit
• DGS3MO - Market Yield on U.S. Treasury Securities at 3-Month Constant Maturity
• DGS2 - Market Yield on U.S. Treasury Securities at 2-Year Constant Maturity
• DGS10 - Market Yield on U.S. Treasury Securities at 10-Year Constant Maturity
• DGS30 - Market Yield on U.S. Treasury Securities at 30-Year Constant Maturity
• T10Y2Y - 10-Year Treasury Constant Maturity Minus 2-Year Treasury Constant Maturity
• CPILFESL - Consumer Price Index for All Urban Consumers: All Items Less Food and Energy
• CPIUFDSL - Consumer Price Index for All Urban Consumers: Food
• CPIENGSL - Consumer Price Index for All Urban Consumers: Energy
• CUSR0000SAH1 - Consumer Price Index for All Urban Consumers: Shelter
• PCEPI - Personal Consumption Expenditures: Chain-type Price Index
• PCEPILFE - Personal Consumption Expenditures Excluding Food and Energy: Chain-type Price Index
• PPIACO - Producer Price Index by Commodity: All Commodities
• T10YIE - 10-Year Breakeven Inflation Rate
• U6RATE - Total Unemployed, Plus All Marginally Attached Workers Plus Total Employed Part Time for Economic Reasons
• PAYEMS - All Employees, Total Nonfarm
• CIVPART - Labor Force Participation Rate
• EMRATIO - Employment-Population Ratio
• UNEMPLOY - Unemployed
• CE16OV - Employment Level
• ICSA - Initial Claims
• JTSJOL - Job Openings: Total Nonfarm
• JTSQUR - Quits: Total Nonfarm
• GDPC1 - Real Gross Domestic Product
• A191RL1Q225SBEA - Real Gross Domestic Product: Percent Change from Preceding Period
• INDPRO - Industrial Production: Total Index
• TCU - Capacity Utilization: Total Index
• HOUST - New Privately-Owned Housing Units Started: Total Units
• PERMIT - New Privately-Owned Housing Units Authorized in Permit-Issuing Places: Total Units
• RSAFS - Advance Retail Sales: Retail Trade
• PCE - Personal Consumption Expenditures
• DSPIC96 - Real Disposable Personal Income
• PSAVERT - Personal Saving Rate
• M2SL - M2
• BOPGSTB - U.S. International Trade in Goods and Services: Balance
• MSPUS - Median Sales Price of Houses Sold for the United States
• HSN1F - New One Family Houses Sold: United States
• RHORUSQ156N - Homeownership Rate in the United States
• TTLCONS - Total Construction Spending: Total Construction in the United States
• RRVRUSQ156N - Rental Vacancy Rate in the United States
• TOTALSL - Total Consumer Credit Owned and Securitized
• REVOLSL - Revolving Consumer Credit Owned and Securitized
• DRCCLACBS - Delinquency Rate on Credit Card Loans, All Commercial Banks
• GDP - Gross Domestic Product
• GPDI - Gross Private Domestic Investment
• GCE - Government Consumption Expenditures and Gross Investment
• PCEC - Personal Consumption Expenditures
• NETEXP - Net Exports of Goods and Services
• GFDEBTN - Federal Debt: Total Public Debt
• GFDEGDQ188S - Federal Debt: Total Public Debt as Percent of Gross Domestic Product
• FYFSD - Federal Surplus or Deficit
• FGRECPT - Federal Government Current Receipts
• FGEXPND - Federal Government: Current Expenditures
• MANEMP - All Employees, Manufacturing
• USCONS - All Employees, Construction
• USTRADE - All Employees, Retail Trade
• USFIRE - All Employees, Financial Activities
• USGOVT - All Employees, Government
• AWHAETP - Average Weekly Hours of All Employees, Total Private
• DGORDER - Manufacturers' New Orders: Durable Goods
• NEWORDER - Manufacturers' New Orders: Nondefense Capital Goods Excluding Aircraft
• BUSINV - Total Business Inventories
• EXPGS - Exports of Goods and Services
• IMPGS - Imports of Goods and Services
• IR - Import Price Index (End Use): All Commodities
• PPIFIS - Producer Price Index by Commodity: Final Demand

Latest quarter (10-Q)

Latest 10-Q source: 0001690585-26-000022.

Extracted structurally from real Item 2 body heading to real Item 3/4 boundary. Confidence: high. Filing date: 2026-05-05. Report date: 2026-03-31.

Item 2. 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 unaudited condensed consolidated financial statements and related notes included elsewhere in this Quarterly Report on Form 10-Q. This discussion contains forward-looking statements that involve risks and uncertainties, including those described in the section titled “Special Note Regarding Forward-Looking Statements” included elsewhere in this Quarterly Report on Form 10-Q. Our actual results and the timing of selected events could differ materially from those discussed below. Factors that could cause or contribute to such differences include, but are not limited to, those identified below and those set forth under the section titled “Risk Factors” included elsewhere in this Quarterly Report on Form 10-Q and in our Annual Report on Form 10-K for the year ended December 31, 2025 filed with the SEC on March 9, 2026.

Overview

We are a clinical-stage biotechnology company dedicated to developing potentially best-in-disease therapies for patients living with severe autoimmune diseases. Our lead clinical-stage candidate, claseprubart, is a monoclonal antibody that is purposefully engineered with extended half-life, improved potency, and high selectivity for only the active C1s complement protein (“C1s”) – enabling less frequent and more convenient self-administered subcutaneous (“S.C.”) injections suitable for a pre-filled pen. Additionally, selective inhibition of the classical complement pathway may lower patient risk of infection from encapsulated bacteria by preserving immune activity of the lectin and alternative pathways. We believe claseprubart has the potential to address a broad array of complement-dependent diseases as currently available therapies and those in development leave room for improvements in efficacy, safety, and/or dosing convenience.

Our second clinical-stage candidate, DNTH212, is a first-in-class and potentially best-in-disease, bifunctional fusion protein that targets plasmacytoid dendritic cell (“pDC”) BDCA2 to reduce Type 1 interferon production, while simultaneously inhibiting BAFF/APRIL to suppress B cell function. By targeting both the innate and adaptive immune systems via two clinically validated pathways that are known drivers of autoimmune disease pathogenesis, this complementary and differentiated approach has the potential to address multiple autoimmune indications with improved outcomes. DNTH212 is also designed with the potential for patient friendly convenient, infrequent, self-administered S.C. injections suitable for a pre-filled pen.

Our Pipeline-in-a-Product Potential for Claseprubart, a Next-Generation Complement Therapeutic

Our most advanced product candidate, claseprubart, is a clinical-stage, highly potent, highly selective and fully human monoclonal immunoglobulin G4 with picomolar binding affinity that is designed to selectively bind only to the active form of C1s. The active form of C1s is generated during complement activation by cleavage of the inactive proC1s. As a validated complement target in the autoimmune and inflammatory field, C1s inhibition prevents further progression of the classical pathway cascade. Claseprubart is engineered with YTE half-life extension technology, a specific three amino acid change in the Fc domain, and has a pharmacokinetic (“PK”) profile designed to support less frequent, lower dose, self-administration as a convenient S.C. injection.

We are currently conducting three mid- to late-stage clinical trials with claseprubart in generalized Myasthenia Gravis (“gMG”), Chronic Inflammatory Demyelinating Polyneuropathy (“CIDP”), and Multifocal Motor Neuropathy (“MMN”).

In September 2025, we reported positive top-line results from the Phase 2 MaGic trial of claseprubart for patients with gMG and subsequently held an end-of-Phase 2 meeting with the FDA in the first quarter of 2026. We expect to initiate a Phase 3 registrational trial in gMG in mid-2026 and report top-line results in the second half of 2028.

In March 2026, we made an early GO announcement in the interim responder analysis for our Phase 3 CAPTIVATE trial of claseprubart in patients with CIDP due to achieving a target of 20 confirmed responders with less than the planned 40 participants completing Part A. We expect to provide CAPTIVATE Part B top-line guidance by the end of 2026.

Claseprubart is also being evaluated in the Phase 2 MoMeNtum trial for patients with MMN, and we anticipate initial top-line results from this trial will be available in the fourth quarter of 2026.

In March 2026, we received written feedback from the FDA agreeing to three proposals for all ongoing and planned future claseprubart trials:

•
Removal of anti-nuclear antibodies (“ANAs”) as a screening criteria, a common reason for screen failure across all three claseprubart programs;

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•
Removal of routine ANA testing during claseprubart clinical trials; and

•
Reclassification of the hypothetical risk of Systemic Lupus Erythematosus to drug-induced lupus (“DIL”), a side effect in several classes of widely used medications characterized by the reversal of symptoms upon discontinuation of the precipitating medication.

On May 1, 2026, claseprubart was granted Orphan Drug Designation by the FDA for the treatment of Myasthenia Gravis. The FDA’s Office of Orphan Products Development grants orphan designation to drugs and biologics intended to treat rare diseases affecting fewer than 200,000 people in the United States. Orphan Drug Designation qualifies sponsors for incentives including tax credits for qualified clinical trials, exemption from user fees, and potential seven years of market exclusivity after approval.

MAGIC

The MaGic trial is a global, randomized, double-blind, placebo-controlled Phase 2 trial of claseprubart that enrolled 65 acetylcholine receptor positive (“AChR+”) participants with gMG. Following an initial loading dose, claseprubart was administered every two weeks (“Q2W”) via S.C. injection at a dose of 300mg/2mL or 600mg/4mL. The initial randomized treatment duration was 13 weeks, followed by a 52-week open-label extension (“OLE”). The primary endpoint of the study was safety and tolerability. Secondary and exploratory efficacy endpoints included Myasthenia Gravis Activities of Daily Living Scale (“MG-ADL”) and Quantitative Myasthenia Gravis (“QMG”) score assessments, as well as Minimal Symptom Expression (“MSE”), Myasthenia Gravis Composite (“MGC”) score, and the Myasthenia Gravis Quality of Life Scale (“MG-QOL-15r”).

In September 2025, we announced positive top-line data from the Phase 2 MaGic trial. Claseprubart 300mg and 600mg demonstrated rapid, statistically significant and clinically meaningful improvements over placebo as measured by both MG-ADL and QMG, including at week 1 and at week 13. The claseprubart 300mg Q2W dose was also statistically significant and clinically meaningful across other key efficacy endpoints, including MSE, MGC, and MG-QoL-15r.

Claseprubart was generally well tolerated with no drug-related serious adverse events (“SAE”) or discontinuations due to any related adverse event. Claseprubart had a favorable clinical safety profile comparable to placebo with no treatment-related serious bacterial infections and no clinical symptoms of emergent autoimmune disorders observed.

In the OLE portion of the MaGic trial, patients who were on placebo during the randomized controlled portion of the trial received claseprubart 600mg Q2W without a loading dose. Data from the OLE demonstrate that after two doses of claseprubart 600mg Q2W, participants experienced robust reductions in MG-ADL and QMG at PK levels far below the steady state of the 300mg Q2W dose, supporting the potential for dosing of 300mg claseprubart every four weeks (“Q4W”).

Based on the outcome of our end-of-Phase 2 meeting with the FDA held in the first quarter of 2026, we expect to initiate a registrational Phase 3 trial of claseprubart evaluating 300mg Q2W and 300mg Q4W in gMG patients in mid-2026 and report top-line results in the second half of 2028.

CAPTIVATE

The CAPTIVATE trial is a single, two-part, randomized withdrawal global Phase 3 trial of claseprubart in patients with CIDP. In the open label Part A of this trial, participants will be administered claseprubart with a loading dose followed by 300mg/2mL administered Q2W via S.C. injection for up to 13 weeks. Only participants who respond to claseprubart in Part A, as measured as greater than or equal to one point decrease (improvement) in adjusted Inflammatory Neuropathy Cause and Treatment (“INCAT”) disability score compared to Part A baseline, are randomized into Part B, a double-blind, placebo-controlled treatment period of up to 52 weeks, where they will be assessed for prevention of relapse, safety and tolerability, followed by an OLE period. Part A included an interim responder analysis of the first 40 participants to complete Part A. Our target for the Part A interim responder analysis was a response rate of 50% or greater (i.e., ≥20 confirmed responders out of first 40 participants to complete Part A) based on precedent set with aC1s inhibition.

In March 2026, we announced that we achieved our target of 20 confirmed responders in Part A early, with less than 40 participants completing Part A, which supported our plan to maintain the claseprubart 300mg/2mL S.C. Q2W dose in Part A; engage with regulators to remove the claseprubart 600mg/4mL S.C. Q2W arm from Part B; and enroll up to 256 patients (previously up to 480) in Part A to randomize 128 patients in Part B (previously 192). We expect to provide CAPTIVATE Part B top-line guidance by the end of 2026. We believe that this single pivotal trial will support a Biologics License Application (“BLA”) filing in adult patients with CIDP.

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MOMENTUM

The MoMeNtum trial is a global, randomized, double-blind, placebo-controlled Phase 2 study designed to evaluate the safety, tolerability, and efficacy of claseprubart in 36 patients with MMN. Following determination of immunoglobulin (“Ig”) dependency and responsiveness, patients will be randomized to receive placebo or claseprubart with a loading dose followed by 300mg/2mL or 600mg/4mL administered Q2W via S.C. injection. The initial S.C. treatment duration is 17 weeks followed by a 52-week OLE. The primary endpoint of this study is safety and tolerability. Secondary endpoints include time to intravenous immunoglobulin (“IVIg”) retreatment, time to relapse, and assessments of muscle and grip strength. We anticipate initial top-line results from this trial to be available in the fourth quarter of 2026.

Our First-In-Class and Potentially Best-In-Disease Bifunctional BDCA2 and BAFF/APRIL Inhibitor (DNTH212)

On October 16, 2025, we entered into an exclusive license agreement with Nanjing Leads Biolabs Co., Ltd. (“Leads”) for DNTH212, a first-in-class and potentially best-in-disease bifunctional BDCA2 and BAFF/APRIL inhibitor.

DNTH212 is an investigational, extended half-life bifunctional fusion protein targeting plasmacytoid dendritic cell BDCA2 to reduce Type 1 interferon production, while simultaneously inhibiting BAFF/APRIL to suppress B cell function. By targeting both the innate and adaptive immune systems via two clinically validated pathways that are known drivers of autoimmune disease pathogenesis, this complementary and differentiated approach has the potential to address multiple autoimmune indications with improved outcomes.

DNTH212 has pipeline-in-a-product potential to serve as the foundation of a synergistic rheumatology franchise, and Sjögren’s Disease, Systemic Lupus Erythematosus, and Dermatomyositis have been selected as the first three prioritized indications for DNTH212 clinical development. These indications are areas of high unmet need, where co

[Excerpt truncated for page length; source filing is linked above.]

Latest 10-K MD&A

Extracted structurally from real Item 7 body heading to real Item 7A/8 boundary. Confidence: high. Filing date: 2026-03-09. Report date: 2025-12-31.

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 on Form 10-K. This discussion contains forward-looking statements that involve risks and uncertainties, including those described in the section titled “Special Note Regarding Forward Looking Statements” included elsewhere in this Annual Report on Form 10-K. Our actual results and the timing of selected events could differ materially from those discussed below. Factors that could cause or contribute to such differences include, but are not limited to, those identified below and those set forth under the section titled “Item 1A. Risk Factors” included elsewhere in this Annual Report on Form 10-K.

Overview

We are a clinical-stage biotechnology company dedicated to developing potentially best-in-class therapies for patients living with severe autoimmune diseases. Our lead clinical-stage candidate, claseprubart, is a monoclonal antibody that is purposefully engineered with extended half-life, improved potency, and high selectivity for only the active C1s complement protein (“C1s”) – enabling less frequent and more convenient self-administered subcutaneous (“S.C.”) injections suitable for a pre-filled pen. Additionally, selective inhibition of the classical complement pathway may lower patient risk of infection from encapsulated bacteria by preserving immune activity of the lectin and alternative pathways. We believe claseprubart has the potential to address a broad array of complement-dependent diseases as currently available therapies and those in development leave room for improvements in efficacy, safety, and/or dosing convenience.

Our second clinical-stage candidate, DNTH212, is a first and potentially best-in-class, bifunctional fusion protein that targets plasmacytoid dendritic cell (“pDC”) BDCA2 to reduce Type 1 interferon production, while simultaneously inhibiting BAFF/APRIL to suppress B cell function. By targeting both the innate and adaptive immune systems via two clinically validated pathways that are known drivers of autoimmune disease pathogenesis, this complementary and differentiated approach has the potential to address multiple autoimmune indications with improved outcomes. DNTH212 is also designed with the potential for patient friendly convenient, infrequent, self-administered S.C. injections suitable for a pre-filled pen.

Our Pipeline-in-a-Product Potential for Claseprubart, a Next-Generation Complement Therapeutic

Our most advanced product candidate, claseprubart, is a clinical-stage, highly potent, highly selective and fully human monoclonal immunoglobulin G4 with picomolar binding affinity that is designed to selectively bind only to the active form of C1s. The active form of C1s is generated during complement activation by cleavage of the inactive proC1s. As a validated complement target in the autoimmune and inflammatory field, C1s inhibition prevents further progression of the classical pathway cascade. Claseprubart is engineered with YTE half-life extension technology, a specific three amino acid change in the Fc domain, and has a pharmacokinetic (“PK”) profile designed to support less frequent, lower dose, self-administration as a convenient S.C. injection.

We are currently conducting three mid- to late-stage clinical trials with claseprubart in generalized Myasthenia Gravis (“gMG”), Chronic Inflammatory Demyelinating Polyneuropathy (“CIDP”), and Multifocal Motor Neuropathy (“MMN”).

In September 2025, we reported positive top-line results from the Phase 2 MaGic trial of claseprubart for patients with gMG and subsequently held an end-of-Phase 2 meeting with the FDA in the first quarter of 2026. We expect to initiate a Phase 3 registrational trial in gMG in mid-2026 and report top-line results in the second half of 2028.

In March 2026, we made an early GO announcement in the interim responder analysis for our Phase 3 CAPTIVATE trial of claseprubart in patients with CIDP due to achieving a target of 20 confirmed responders with less than the planned 40 participants completing Part A.

Claseprubart is also being evaluated in the Phase 2 MoMeNtum trial for patients with MMN, and we anticipate initial top-line results from this trial will be available in the second half of 2026.

MAGIC

The MaGic trial is a global, randomized, double-blind, placebo-controlled Phase 2 trial of claseprubart that enrolled 65 acetylcholine receptor positive (“AChR+”) participants with gMG. Following an initial loading dose, claseprubart was administered every two weeks (“Q2W”) via S.C. injection at a dose of 300mg/2mL or 600mg/4mL. The initial randomized treatment duration was 13 weeks, followed by a 52-week open-label extension (“OLE”). The primary endpoint of the study was safety and tolerability. Secondary and exploratory efficacy endpoints included Myasthenia Gravis Activities of Daily Living Scale (“MG-ADL”) and Quantitative Myasthenia Gravis (“QMG”) score assessments, as well as Minimal Symptom Expression (“MSE”), Myasthenia Gravis Composite (“MGC”) score, and the Myasthenia Gravis Quality of Life Scale (“MG-QOL-15r”).

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In September 2025, we announced positive top-line data from the Phase 2 MaGic trial. Claseprubart 300mg and 600mg demonstrated rapid, statistically significant and clinically meaningful improvements over placebo as measured by both MG-ADL and QMG, including at week 1 and at week 13. The claseprubart 300mg Q2W dose was also statistically significant and clinically meaningful across other key efficacy endpoints, including MSE, MGC, and MG-QoL-15r.

Claseprubart was generally well tolerated with no drug-related serious adverse events (“SAE”) or discontinuations due to any related adverse event. Claseprubart had a favorable clinical safety profile comparable to placebo with no treatment-related serious bacterial infections and no clinical symptoms of emergent autoimmune disorders observed.

In the OLE portion of the MaGic trial, patients who were on placebo during the randomized controlled portion of the trial received claseprubart 600mg Q2W without a loading dose. Data from the OLE demonstrate that after two doses of claseprubart 600mg Q2W, participants experienced robust reductions in MG-ADL and QMG at PK levels far below the steady state of the 300mg Q2W dose, supporting the potential for dosing of 300mg claseprubart every four weeks (“Q4W”).

Based on the outcome of our end-of-Phase 2 meeting with the FDA held in the first quarter of 2026, we expect to initiate a registrational Phase 3 trial of claseprubart evaluating 300mg Q2W and 300mg Q4W in gMG patients in mid-2026 and report top-line results in the second half of 2028.

CAPTIVATE

The CAPTIVATE trial is a single, two-part, randomized withdrawal global Phase 3 trial of claseprubart in patients with CIDP. In the open label Part A of this trial, participants will be administered claseprubart with a loading dose followed by 300mg/2mL administered Q2W via S.C. injection for up to 13 weeks. Only participants who respond to claseprubart in Part A, as measured as greater than or equal to one point decrease (improvement) in adjusted Inflammatory Neuropathy Cause and Treatment (“INCAT”) disability score compared to Part A baseline, are randomized into Part B, a double-blind, placebo-controlled treatment period of up to 52 weeks, where they will be assessed for prevention of relapse, safety and tolerability, followed by an OLE period. Part A included an interim responder analysis of the first 40 participants to complete Part A. Our target for the Part A interim responder analysis was a response rate of 50% or greater (i.e., ≥20 confirmed responders out of first 40 participants to complete Part A) based on precedent set with aC1s inhibition. In March 2026, we announced that we achieved our target of 20 confirmed responders in Part A early, with less than 40 participants completing Part A. We believe that this single pivotal trial will support a Biologics License Application (“BLA”) filing in adult patients with CIDP.

MOMENTUM

The MoMeNtum trial is a global, randomized, double-blind, placebo-controlled Phase 2 study designed to evaluate the safety, tolerability, and efficacy of claseprubart in 36 patients with MMN. Following determination of Ig dependency and responsiveness, patients will be randomized to receive placebo or claseprubart with a loading dose followed by 300mg/2mL or 600mg/4mL administered Q2W via S.C. injection. The initial S.C. treatment duration is 17 weeks followed by a 52-week OLE. The primary endpoint of this study is safety and tolerability. Secondary endpoints include time to intravenous immunoglobulin (“IVIg”) retreatment, time to relapse, and assessments of muscle and grip strength. We anticipate initial top-line results from this trial to be available in the second half of 2026.

Our First and Potentially Best-In-Class Bifunctional BDCA2 and BAFF/APRIL Inhibitor (DNTH212)

On October 16, 2025, we entered into an exclusive license agreement with Nanjing Leads Biolabs Co., Ltd. (“Leads”) for DNTH212, a first and potentially best-in-class bifunctional BDCA2 and BAFF/APRIL inhibitor.

DNTH212 is an investigational, extended half-life bifunctional fusion protein targeting plasmacytoid dendritic cell BDCA2 to reduce Type 1 interferon production, while simultaneously inhibiting BAFF/APRIL to suppress B cell function. By targeting both the innate and adaptive immune systems via two clinically validated pathways that are known drivers of autoimmune disease pathogenesis, this complementary and differentiated approach has the potential to address multiple autoimmune indications with improved outcomes.

A two-part Phase 1 study in China in healthy volunteers (Part A) and patients with systemic lupus erythematosus (Part B) was initiated in December 2025, with top-line results in healthy volunteers expected in the second half of 2026.

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Corporate Update

September 2025 Public Offering

On September 9, 2025, we entered into an underwriting agreement with certain underwriters to issue and sell 7,627,879 shares of our common stock, including the full exercise by the underwriters of their option to purchase an additional 1,140,000 shares, at a public offering price of $33.00 per share and, in lieu of common stock to certain investors, pre-funded warrants to purchase 1,112,121 shares of our common stock at a public offering price of $32.999 per share, which represented the per share public offering price for the common stock less the $0.001 per share exercise price for each pre-funded warrant. The gross proceeds from the underwritten offering were $288.4 million, before underwriting discounts and commissions and expenses of the offering. The underwritten offering closed on September 11, 2025.

The pre-funded warrants are exercisable at any time after the date of issuance. A holder of the pre-funded warrants may not exercise the warrant if the holder, together with its affiliates, would beneficially own more than 4.99%, 9.99%, or 19.99%, as applicable to each holder, of the number of shares of common stock outstanding immediately after giving effect to such exercise. A holder of the pre-funded warrants may increase or decrease this percentage to a percentage not in excess of 19.99% by providing us with at least 61 days’ prior notice.

We intend to use the net proceeds from this underwritten offering to advance our preclinical and clinical development activities, as well as for working capital and general corporate purposes. We may also use a portion of the proceeds to license, acquire or invest in new product candidates or for drug development activities related to such product candidates, complementary businesses, technology, or assets.

The underwritten offering was made pursuant to a shelf registration statement, which became effective on October 9, 2024. A final prospectus supplement dated September 9, 2025 relating to and describing the terms of the underwritten offering was filed with the SEC on September 11, 2025.

Global and Macroeconomic Developments

Uncertainty in the global economy presents significant risks to our business. We are subject to continuing risks and uncertainties in connection with legislative, regulatory, political, geopolitical and macroeconomic developments beyond our control, including inflationary pressures, a general economic slowdown or a recession, high interest rates, changes in monetary policy or foreign currency exchange rates, changes in trade policies, including tariffs and other trade restrictions or the threat of such actions, instability in financial institutions, the ongoing conflict in Ukraine, conflicts in the Middle East, rising tensions between China and Taiwan, the attacks on marine vessels traversing the Red Sea and the responses thereto, and supply chain disruptions. While we are closely monitoring the impact of the current macroeconomic conditions on all aspects of our business, including the impacts on participants in our clinical trials, employees, suppliers, vendors, business partners and regulators, the ultimate extent of the impact on our business remains highly uncertain and will depend on future developments and factors that continue to evolve. Most of these developments and factors are outside of our control and could exist for an extended period of time. We will continue to evaluate the nature and extent of the potential impacts to our business, results of operations, liquidity and capital resources. For additional information, see the section titled “Item 1A. Risk Factors” found elsewhere in this Annual Report on Form 10-K.

Components of Results of Operations

Revenues

Since inception, we have not generated any revenue from product sales, and we do not expect to generate any revenue from the sales of products in the foreseeable future. We have recognized revenues attributable to upfront payments, milestone payments and cost reimbursements under our license agreements.

If our development efforts for claseprubart, DNTH212, or any other future product candidates, if any, are successful and result in regulatory approval, we may generate revenue from future product sales. If we enter into license or collaboration agreements for claseprubart, DNTH212, or any other future product candidates, if any, or intellectual property, revenue may be generated in the future from such license or collaboration agreements. We cannot predict if, when, or to what extent we will generate revenue from the commercialization and sale of claseprubart, DNTH212, or any other future product candidates or from license or collaboration agreements. We may never succeed in obtaining regulatory approval for claseprubart, DNTH212, or any other future product candidates.

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Licensing Agreements

In June 2022, we executed a license agreement with Zenas BioPharma, Inc. (formerly Zenas BioPharma Limited) (“Zenas”), a former related party, which provided Zenas with a license in Greater China for the development and commercialization of certain sequences and products under an identified antibody sequence (the “Zenas License Agreement”). The Zenas License Agreement included the following payments from Zenas: (i) a non-refundable upfront payment of $1.0 million; (ii) an approximately $1.1 million reimbursement payment for a portion of development costs previously incurred by us; (iii) reimbursement of a portion of all chemistry, manufacturing and control (“CMC”)-related costs and expenses for the first antibody sequence through the manufacture of the first two batches of drug product; (iv) reimbursement of a portion of all non-CMC-related costs and expenses for the development of the first antibody sequence through the first regulatory approval; (v) development milestones totaling up to $11.0 million; and (vi) royalties on net sales ranging from the mid-single digits to the low teen percentages.

On October 21, 2024, Zenas assigned the Zenas License Agreement to its affiliated entity, Zenas BioPharma (HK) Limited (“Zenas HK”). After the assignment, we entered into a novation agreement (the “Novation Agreement”) with Zenas and Tenacia Biotechnology (Hong Kong) Co., Limited (“Tenacia”) and an amendment to the Zenas License Agreement, now with Tenacia (as amended, the “Tenacia License Agreement”), pursuant to which Tenacia replaced Zenas HK as a party to the Zenas Agreements and certain economic terms under the Zenas License Agreement with respect to cost sharing and development milestones were amended.

Except as stated otherwise, the economic terms of the Zenas License Agreement were unchanged when novated by the Novation Agreement and amended by the Tenacia License Agreement.

The consideration under the Tenacia License Agreement, which replaced the consideration of the Zenas License Agreement, related to the first antibody sequence includes the following payments by Tenacia to us: (i) a $2.5 million upfront payment, which was paid by Tenacia to us in October 2024 upon execution of the Tenacia License Agreement; (ii) reimbursement of a portion of certain clinical costs; (iii) development milestones totaling up to $15.0 million; and (iv) royalties on net sales ranging from the mid-single digits to the low teen percentages. Tenacia is also responsible for paying local development costs in Greater China and a portion of central development costs based on the number of patients enrolled from China in our global Phase 3 studies. No milestones were achieved under the Zenas Agreements prior to novation. During the year ended December 31, 2025, we achieved $6.0 million of milestone payments under the Tenacia Agreements (as defined below), which were added to the transaction price. We had not recorded any royalty revenue under the Zenas Agreement prior to novation, and we have not recorded any royalty revenue under the Tenacia Agreements.

Under the Zenas License Agreement, Zenas also had the right to exercise an option with respect to a second antibody sequence, which is now held by Tenacia (the “Tenacia Option” and, together with the Tenacia License Agreement, the “Tenacia Agreements”). Pursuant to the Tenacia Option, if Tenacia exercises the option and pays us the option exercise fee related to the second antibody sequence, we will grant Tenacia an exclusive license to the sequences and licensed products under this second antibody sequence. The economic terms with respect to this second antibody sequence were unchanged by the amendment to the Zenas License Agreement.

For the years ended December 31, 2025 and 2024, we recognized related party license revenue totaling nil and $5.9 million, respectively, associated with the Zenas Agreements.

For the years ended December 31, 2025 and 2024, we recognized license revenue totaling $2.0 million and $0.3 million, respectively, associated with the Tenacia Agreements.

Operating Expenses

Research and Development

Research and development expenses account for a significant portion of our operating expenses and consist primarily of external and internal expenses incurred in connection with the discovery and development of claseprubart, DNTH212 and other potential product candidates.

External expenses include:

•
payments to third parties in connection with research and development, including agreements with third parties, such as contract research organizations (“CROs”), clinical trial sites and consultants;

•
the cost of manufacturing products for use in our clinical trials and preclinical studies, including payments to contract development and manufacturing organizations (“CDMOs”) and consultants; and

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•
payments to third parties in connection with the preclinical development of other potential product candidates, including for outsourced professional scientific development services, consulting research and collaborative research.

Internal expenses include:

•
personnel-related costs, including salaries, bonuses, related benefits and stock-based compensation expenses for employees engaged in research and development functions; and

•
depreciation, supplies, travel expenses and other allocated expenses.

We recognize research and development expenses in the periods in which they are incurred. Our internal resources, employees and infrastructure are not directly tied to any one research or drug discovery program and are typically deployed across multiple programs. External expenses are recognized based on an evaluation of the progress to completion of specific tasks using information provided to us by our service providers or our estimate of the level of service that has been performed at each reporting date. We utilize CROs for research and development activities and CDMOs for manufacturing activities and we do not have laboratory or manufacturing facilities. Therefore, we have no material facilities expenses attributed to research and development.

Product candidates in later stages of development generally have higher development costs than those in earlier stages. As a result, we expect that our research and development expenses will increase substantially over the next several years as we advance claseprubart into larger and later-stage clinical trials, develop DNTH212, work to discover and develop additional product candidates, seek to expand, maintain, protect and enforce our intellectual property portfolio and hire additional research and development personnel.

The successful development of claseprubart, DNTH212, or any other future product candidates, if any, is highly uncertain, and we do not believe it is possible at this time to accurately project the nature, timing and estimated costs of the efforts necessary to complete the development of, and obtain regulatory approval for, claseprubart, DNTH212, or any other future product candidates, if any. To the extent claseprubart, DNTH212, or any other future product candidates advance into larger and later-stage clinical trials, our expenses will increase substantially and may become more variable. The duration, costs and timing of development of claseprubart, DNTH212, or any other future product candidates are subject to numerous uncertainties and will depend on a variety of factors, including:

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

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

•
our ability to establish a favorable safety profile with Investigational New Drug application (“IND”)-enabling toxicology studies to enable clinical trials;

•
successful patient enrollment in, and the initiation and completion of, larger and later-stage clinical trials;

•
per subject trial costs;

•
the number and extent of our clinical trials required for regulatory approval;

•
the countries in which our clinical trials are conducted;

•
the length of time required to enroll eligible subjects in our clinical trials;

•
the number of subjects that participate in our clinical trials;

•
the drop-out and discontinuation rate of subjects in our clinical trials;

•
potential additional safety monitoring requested by regulatory agencies;

•
the duration of subject participation in our clinical trials and follow-up;

•
the extent to which we encounter any serious adverse events in our clinical trials;

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•
the timing of receipt of regulatory approvals from applicable regulatory authorities;

•
the timing, receipt and terms of any marketing approvals and post-marketing approval commitments from applicable regulatory authorities;

•
the extent to which we establish collaborations, strategic partnerships, or other strategic arrangements with third parties, if any, and the performance of any such third party;

•
hiring and retaining research and development personnel;

•
our arrangements with our CDMOs and CROs;

•
development and timely delivery of commercial-grade drug formulations that can be used in our planned clinical trials and for commercial launch;

•
the impact of any business interruptions to our operations or to those of the third parties with whom we work; and

•
obtaining, maintaining, defending and enforcing patent claims and other intellectual property rights.

Any of these factors could significantly impact the costs, timing and viability associated with the development of claseprubart, DNTH212, or any other future product candidates.

General and Administrative Expenses

General and administrative expenses primarily consist of salaries, bonuses, related benefits, and stock-based compensation expense for personnel in executive, finance, and administrative functions; professional fees for legal, consulting, accounting, and audit services; and travel expenses, technology costs, and other allocated expenses. General and administrative expenses also include corporate facility costs, including insurance, rent, utilities, depreciation, and maintenance, not otherwise included in research and development expenses. We recognize general and administrative expenses in the periods in which they are incurred.

We expect that our general and administrative expenses will increase in the future to support our continued research and development activities, pre-commercial preparation activities for the product candidates and, if any product candidate receives marketing approval, commercialization activities. In addition, we will continue to incur expenses associated with being a public company, including expenses related to accounting, audit, legal, regulatory, public company reporting and compliance, director and officer insurance, investor and public relations, and other administrative and professional services.

Other Income/(Expense)

Other income/(expense) consists primarily of interest and investment income generated from earnings on invested cash and investment securities.

Income Tax

Since inception, we have not recorded any U.S. federal or state income tax benefits for the net losses we have incurred in each year or for our earned research tax credits due to uncertainty of realizing a benefit from those items. We maintain a full valuation allowance on our federal and state deferred tax assets as we have concluded that it is more likely than not that the deferred assets will not be utilized.

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Results of Operations

A discussion regarding our financial condition and results of operations for the year ended December 31, 2025 compared to the year ended December 31, 2024 is presented below. A discussion regarding our financial condition and results of operations for the year ended December 31, 2024 compared to the year ended December 31, 2023 can be found in “Management’s Discussion and Analysis of Financial Condition and Results of Operations” in our Annual Report on Form 10-K filed with the SEC on March 11, 2025.

Comparison of the Years Ended December 31, 2025 and 2024

The following table summarizes our results of operations and other comprehensive loss for the periods indicated:

Year Ended

December 31,

2025

2024

(in thousands)

Revenues:

License revenue - former related party

$

—

$

5,909

License revenue

2,036

326

Total revenues

2,036

6,235

Operating expenses:

Research and development

145,638

83,105

General and administrative

34,331

24,994

Total operating expenses

179,969

108,099

Loss from operations

(177,933

)

(101,864

)

Other income/(expense):

Interest and investment income

16,119

17,365

Gain on investment in former related party

508

148

Loss on currency exchange, net

(57

)

(64

)

Other expense

(974

)

(554

)

Total other income

15,596

16,895

Net loss

$

(162,337

)

$

(84,969

)

Revenues

Under the terms of the Zenas Agreements, we recognized related party license revenue of nil and $5.9 million during the years ended December 31, 2025 and 2024, respectively. Additionally, under the terms of the Tenacia Agreements, we recognized license revenue of $2.0 million and $0.3 million for the years ended December 31, 2025 and 2024, respectively. The decrease in total revenues was due to a decrease of reimbursable costs associated with claseprubart’s ongoing clinical trials that were subject to the Zenas Agreements and are subject to the Tenacia Agreements.

Research and Development Expenses

Research and development expenses were $145.6 million for the year ended December 31, 2025, as compared to $83.1 million for the year ended December 31, 2024, an increase of $62.5 million. This increase was due to: (1) a $47.7 million increase in external research and development costs, consisting of clinical operation activities, CMC activities, preclinical study costs, discovery expenses and licensing and milestone payments; and (2) a $14.8 million increase in internal research and development costs, consisting of personnel and related costs, stock-based compensation expense and other costs.

The $47.7 million increase in external research and development costs was due to a $30.0 million increase in expenses related to discovery activities and a $17.7 million increase in expenses related to claseprubart. The increase in discovery activities related primarily to the upfront and clinical development milestone payments of $30.0 million for the DNTH212 program. The increase in expenses related to claseprubart were due to increases of $24.1 million in clinical operations activities and $1.5 million in licensing and milestone payments, partially offset by decreases of $4.9 million in preclinical study costs and $3.0 million in CMC activities. The changes related to claseprubart’s ongoing Phase 2 clinical trials in gMG and MMN and Phase 3 clinical trial in CIDP.

The $14.8 million increase in internal research and development costs was due to increases of $9.3 million in personnel and related costs, $4.5 million in stock-based compensation expense and $1.0 million in other expenses. The increases were due to the

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buildout of our internal research and development function to support our Phase 2 and Phase 3 clinical trials in claseprubart and development of DNTH212.

General and Administrative Expenses

General and administrative expenses were $34.3 million for the year ended December 31, 2025, as compared to $25.0 million for the year ended December 31, 2024, an increase of $9.3 million. The increase was primarily due to increases of $5.4 million in stock-based compensation expense, $3.3 million in personnel and related costs and $0.6 million in other administrative costs. The increases in costs were due to the buildout of our general and administrative function to support our Phase 2 and Phase 3 clinical trials in claseprubart and development of DNTH212.

Other Income/(Expense)

Other income was $15.6 million for the year ended December 31, 2025, as compared to $16.9 million for the year ended December 31, 2024, a decrease of $1.3 million. The decrease was primarily due to a decrease of $1.3 million in interest income from a lower average investment balance and lower interest rates on investments and an increase of $0.4 million in other expense, partially offset by $0.4 million increased gain on an investment in a former related party.

Income Tax

The provision for income taxes consists primarily of income taxes related to federal and state jurisdictions in which we conduct business. We maintain a full valuation allowance on our federal and state deferred tax assets as we have concluded that it is more likely than not that the deferred assets will not be utilized.

Liquidity and Capital Resources

Sources of Liquidity

Since inception, we have not generated any revenue from product sales and have incurred significant operating losses and negative cash flows from operations. We expect to continue to incur significant expenses and operating losses for the foreseeable future as we advance the clinical development of our lead product candidate, claseprubart, DNTH212, or any other future product candidates. We expect that our research and development and general and administrative costs will continue to increase significantly, including in connection with conducting clinical trials and manufacturing for our lead product candidate, claseprubart, DNTH212, or any other future product candidates to support potential future commercialization and providing general and administrative support for our operations, including the costs associated with operating as a public company. As a result, we will need additional capital to fund our operations, which we may obtain from additional equity or debt financings, collaborations, licensing arrangements or other sources. See the section titled “Risk Factors” found elsewhere in this Annual Report on Form 10-K for additional risks associated with our substantial capital requirements.

We have an open market sales agreement (the “ATM Agreement”) pursuant to which we may sell, from time-to-time shares of our common stock under an at-the-market (“ATM”) offering for an aggregate sales price of up to $200 million. Any sales of our common stock pursuant to the ATM Agreement are made under our registration statement on Form S-3 which was deemed effective by the SEC on October 9, 2024. As of the date of this filing, we have sold 2,626,834 shares of our common stock under the ATM offering program and have $100.1 million in remaining capacity under the ATM offering program. There were no sales under the ATM offering program during the three months ended December 31, 2025.

We historically have funded our operations with proceeds from the sale of capital stock. As of the date of this filing, we have raised aggregate gross proceeds of $288.4 million from public offerings, $423.5 million from private placements, and $99.9 million from our ATM offering program.

Future Capital Requirements

Since inception, we have devoted substantially all of our resources to conducting research and development activities (including with respect to the claseprubart program and DNTH212) and undertaking preclinical studies, conducting clinical trials and the manufacturing of the product used in our clinical trials and preclinical studies, business planning, developing and maintaining our intellectual property portfolio, hiring personnel, raising capital, and providing general and administrative support for these activities.

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We do not own or operate, and currently have no plans to establish, any significant laboratory or manufacturing facilities. We rely, and expect to continue to rely, on third parties for the testing and manufacture of our product candidates, as well as for commercial manufacturing should any of our product candidates obtain marketing approval. We believe this strategy allows us to maintain a more efficient infrastructure by eliminating the need to invest in our own significant laboratory and manufacturing facilities, equipment, and personnel while also enabling us to focus expertise and resources on the development of our product candidates.

We have not generated any revenue from product sales. We do not expect to generate any meaningful product revenue unless and until we obtain regulatory approval of and commercialize claseprubart, DNTH212, or any other future product candidates, and we do not know when, or if, that will occur. In order to complete the development of claseprubart, DNTH212, or any other future product candidates and to build the sales, marketing and distribution infrastructure that we believe will be necessary to commercialize product candidates, if approved, we will require substantial additional capital. Accordingly, until such time that we can generate a sufficient amount of revenue from product sales or other sources, if ever, we expect to seek to raise any necessary additional capital through private or public equity or debt financings, loans or other capital sources, which could include income from collaborations, partnerships or other marketing, distribution, licensing or other strategic arrangements with third parties, or from grants. To the extent that we raise additional capital through equity financings, such as our ATM offering program, 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 equity financing, if available, may involve agreements that include covenants limiting or restricting our ability to take specific actions, including restricting our operations and limiting our ability to incur liens, issue additional debt, pay dividends, repurchase our common stock, make certain investments or engage in merger, consolidation, licensing, or asset sale transactions. If we raise capital through collaborations, partnerships, and other similar arrangements with third parties, we may be required to grant rights to develop and market product candidates that we would otherwise prefer to develop and market ourselves. We may be unable to raise additional capital from these sources on favorable terms, or at all. Our ability to raise additional capital may be adversely impacted by potential worsening global economic conditions and the disruptions to, and volatility in, the credit and financial markets in the United States and worldwide resulting from bank failures, other general macroeconomic conditions and otherwise. Our failure to obtain sufficient capital on acceptable terms when needed could have a material adverse effect on our business, results of operations or financial condition, including requiring us to seek other alternatives which may include, among others, a delay or termination of our clinical trials or the development of our product candidates, temporary or permanent curtailment of our operations, a sale of our assets, or other alternatives with strategic or financial partners. We cannot provide assurance that we will ever generate positive cash flow from operating activities.

Historically, we have funded our operations with proceeds from the sale of capital stock. As of the date of this filing, we have raised aggregate gross proceeds of $288.4 million from public offerings, $423.5 million from private placements, and $99.9 million from our ATM offering program. However, we have incurred significant recurring losses. We generated net losses of $162.3 million and $85.0 million for the years ended December 31, 2025 and 2024, respectively. As of December 31, 2025, we had an accumulated deficit of $336.7 million. Our net losses may fluctuate significantly from quarter-to-quarter and year-to-year, depending on a variety of factors, including the timing, scope and results of our research and development activities. As of December 31, 2025, we had cash, cash equivalents and investments of $514.4 million. Based on our current operating plan, we believe that our existing cash, cash equivalents and investments as of December 31, 2025 should be sufficient to fund our operations into 2028. Until we achieve profitability, we plan to fund our operations and capital expenditures with cash on hand and expect to seek to raise any necessary additional capital through private or public equity or debt financings, loans or other capital sources, which could include income from collaborations, partnerships or other marketing, distribution, licensing or other strategic arrangements with third parties, or from grants. There can be no assurance that we will be successful in raising additional capital or that such capital, if available, will be on terms that are acceptable to us.

We based projections of operating capital requirements on our current operating plan, which includes several assumptions that may prove to be incorrect, and we may use all of our available capital resources sooner than we expect.

Because of the numerous risks and uncertainties associated with research, development and commercialization of product candidates, we are unable to estimate the exact amount and timing of our capital requirements. Our future funding requirements will depend on many factors, including:

•
the scope, timing, progress, results, and costs of researching and developing claseprubart, and conducting larger and later-stage clinical trials;

•
the scope, timing, progress, results, and costs of researching and developing DNTH212 or any other future product candidates that we may pursue;

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

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•
the costs of future activities, including product sales, medical affairs, marketing, manufacturing, and distribution, for any of our product candidates for which we receive marketing approval;

•
the costs of manufacturing commercial-grade products and sufficient inventory to support commercial launch;

•
the revenue, if any, received from commercial sale of our products, should any of our product candidates receive marketing approval;

•
the cost and timing of attracting, hiring, and retaining skilled personnel to support our operations and continued growth;

•
the costs of preparing, filing and prosecuting patent applications, maintaining and enforcing our intellectual property rights and defending intellectual property-related claims;

•
our ability to establish, maintain, and derive value from collaborations, partnerships or other marketing, distribution, licensing, or other strategic arrangements with third parties on favorable terms, if at all;

•
the extent to which we acquire or in-license other product candidates and technologies, if any; and

•
the costs associated with operating as a public company.

A change in the outcome of any of these or other factors 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 capital to meet the capital requirements associated with such operating plans.

Cash Flows

The following table summarizes our cash flows for the periods indicated:

Year Ended

December 31,

2025

2024

(in thousands)

Net cash used in operating activities

$

(129,060

)

$

(78,180

)

Net cash used in investing activities

(122,833

)

(286,812

)

Net cash provided by financing activities

280,125

255,623

Increase/(decrease) in cash, cash equivalents and restricted cash

$

28,232

$

(109,369

)

Cash Flows from Operating Activities

For the year ended December 31, 2025, net cash used in operating activities consisted of a net loss of $162.3 million, partially offset by net non-cash operating expenses of $16.5 million and a decrease in net operating assets and liabilities of $16.7 million. The non-cash operating expenses consisted primarily of stock-based compensation expense of $22.8 million, amortization of right-of-use operating lease assets of $0.3 million and depreciation expense of $0.1 million, partially offset by accretion of discount on investment securities of $6.2 million and a gain on an investment in a former related party of $0.5 million. The decrease in net operating assets and liabilities was primarily attributable to increases in accounts payable, accrued expenses and operating lease liabilities of $11.3 million and deferred revenue of $4.6 million and decreases in receivables from Zenas of $0.8 million and other assets of $0.3 million, partially offset by increases in prepaid expenses and other current assets of $0.2 million and accounts receivable of $0.1 million.

For the year ended December 31, 2024, net cash used in operating activities consisted of a net loss of $85.0 million and an increase in net operating assets and liabilities of $0.4 million, partially offset by net non-cash operating expenses of $7.1 million. The increase in net operating assets and liabilities was primarily attributable to increases in other assets of $8.2 million, prepaid expenses and other current assets of $1.6 million, and receivables from a former related party of $0.5 million, partially offset by increases in accounts payable, accrued expenses and operating lease liabilities of $8.2 million and deferred revenue of $1.5 million and a decrease in unbilled receivable from a former related party of $0.2 million. The non-cash operating expenses consisted primarily of stock-based compensation expense of $12.9 million and amortization of right-of-use operating lease assets of $0.3 million, partially offset by accretion of discount on investment securities of $6.0 million and a gain on an investment in a former related party of $0.1 million.

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Cash Flows from Investing Activities

For the year ended December 31, 2025, net cash used in investing activities consisted primarily of $435.0 million of purchases of investment securities and capital expenditures of $0.2 million, partially offset by $312.4 million of proceeds from sales and maturities of investment securities.

For the year ended December 31, 2024, net cash used in investing activities consisted primarily of $413.7 million of purchases of investment securities and capital expenditures of $0.1 million, partially offset by $127.0 million of proceeds from sales and maturities of investment securities.

Cash Flows from Financing Activities

For the year ended December 31, 2025, net cash provided by financing activities consisted of $271.9 million of net proceeds from a public offering, $7.9 million of proceeds from the exercise of stock options and $0.3 million of proceeds from the issuance of stock under the employee stock purchase plan.

For the year ended December 31, 2024, net cash provided by financing activities consisted of $215.3 million of net proceeds from the private placement, $39.2 million of net proceeds from the ATM offering program and $1.1 million of proceeds from the exercise of stock options.

Contractual Obligations and Commitments

Lease Obligations

We lease administrative office space under operating lease agreements in New York, New York, and Waltham, Massachusetts, which expire in February 2031 and January 2027, respectively.

Research and Development and Manufacturing Agreements

We enter into agreements with certain vendors for the provision of goods and services, which includes manufacturing services with CDMOs and development and clinical trial services with CROs. These agreements may include certain provisions for purchase obligations and termination obligations that could require payments for the cancellation of committed purchase obligations or for early termination of the agreements. The amount of the cancellation or termination payments vary and are based on the timing of the cancellation or termination and the specific terms of the agreement. These obligations and commitments are not presented separately.

License and Collaboration Agreements

In October 2025, we entered into a license agreement with Leads, pursuant to which Leads granted us a royalty-bearing, exclusive license outside Greater China to develop, manufacture, commercialize, or otherwise exploit DNTH212, a bifunctional fusion protein being developed in China by Leads as LBL-047. We also obtained certain non-exclusive rights to perform development and manufacturing activities in Greater China to support DNTH212 outside of Greater China. DNTH212 is an investigational, extended half-life bifunctional fusion protein targeting plasmacytoid dendritic cell BDCA2 to reduce Type 1 interferon production, while simultaneously inhibiting BAFF/APRIL to suppress B cell function. We are obligated to pay Leads up to $38.0 million, comprised of $30.0 million in upfront and near-term milestone payments plus an additional $8.0 million milestone, payable in cash or our common stock at our election, upon the initiation of a Dianthus-led Phase 1 study, for exclusive rights to develop and commercialize DNTH212 globally outside of Greater China. We are also obligated to pay up to $962.0 million in development and regulatory approval milestones across three key geographies and sales-based milestones across five indications, as well as tiered royalties from mid-single digits up to a low double-digit on ex-Greater China net sales.

During the three months ended December 31, 2025, we paid Leads $25.0 million in upfront and near-term milestone payments. In addition, we recorded $5.0 million of milestone payments within the accounts payable line item on our consolidated balance sheet as of December 31, 2025.

In July 2020, we entered into a collaborative research agreement with IONTAS Limited (“IONTAS”) to perform certain milestone-based research and development activities under our first development program. We are obligated to pay development and commercial milestone payments of up to £5.4 million (approximately $7.3 million based on the December 31, 2025 exchange rate) with the first development program, which has been selected for the claseprubart program.

In August 2019, we entered into a license agreement with Alloy Therapeutics, LLC (“Alloy”) for (i) a worldwide, non-exclusive license to use the Alloy technology solely to generate Alloy antibodies and platform assisted antibodies for internal, non-clinical

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research purposes, and (ii) with respect to Alloy antibodies and platform assisted antibodies that are selected by us for inclusion into a partnered antibody program, a worldwide, assignable license to make, have made, use, offer for sale, sell, import, develop, manufacture, and commercialize products comprising partnered antibody programs selected from Alloy antibodies and platform assisted antibodies in any field of use. In addition to annual license fees, we are obligated to pay development and commercial milestone payments of up to $12.8 million for the first partnered antibody, which has been selected for the claseprubart program.

Critical Accounting Policies and Estimates

Our financial statements are prepared in accordance with generally accepted accounting principles in the United States of America (“U.S. GAAP”). The preparation of the financial statements and related disclosures requires management to make estimates and judgments that affect the reported amounts of assets, liabilities, costs and expenses, and the disclosure of contingent assets and liabilities in our financial statements. We base our estimates on historical experience, known trends and events and various other factors that we believe are reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. We evaluate estimates and assumptions on a periodic basis. Our actual results may differ materially from these estimates.

While our significant accounting policies are described in more detail in the notes to our consolidated financial statements appearing elsewhere in this Annual Report on 10-K, we believe that the following accounting policies are critical to understanding our historical and future performance, as the policies relate to the more significant areas involving management’s judgments and estimates used in the preparation of our financial statements.

Research and Development Expenses

Research and development expenses are recorded as an expense, as incurred. Research and development expenses consists of: (i) costs to engage contractors who specialize in our development activities; (ii) external research and development costs incurred under arrangements with third parties, such as CROs, CDMOs and consultants; and (iii) costs associated with preclinical and clinical activities and regulatory operations.

We enter into consulting, research, and other agreements with commercial firms, researchers, and others for the provision of goods and services. Under such agreements, we may pay for services on a monthly, quarterly, project or other basis. Such arrangements are generally cancelable upon reasonable notice and payment of costs incurred. Costs are considered incurred based on an evaluation of the progress to completion of specific tasks under each contract using information and data provided to us by our service providers or our estimate of the level of service that has been performed at each reporting date, whereas payments are dictated by the terms of each agreement. As such, depending on the timing of payment relative to the receipt of goods or services, we may record either prepaid expenses or accrued services. These costs consist of direct and indirect costs associated with specific projects, as well as fees paid to various entities that perform certain research and development activities on our behalf.

We make estimates of our accrued expenses as of each balance sheet date in our consolidated financial statements based on facts and circumstances known to us at that time. There may also be instances in which payments made to our vendors will exceed the level of services provided and result in a prepayment of the expense. In accruing expenses, 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 the estimate, we adjust the accrual or the amount of prepaid expense accordingly. Although we do not expect our estimates to be materially different from amounts actually incurred, our understanding of the status and timing of services performed relative to the actual status and timing of services performed may vary and may result in reporting amounts that are too high or too low in any particular period. To date, there have not been any material adjustments to our prior estimates of accrued or prepaid research and development expenses.

Revenue Recognition - Licensing Agreements

We analyze our licensing agreements pursuant to ASC 606, Revenue from Contracts with Customers (“ASC 606”). This assessment is performed throughout the life of the arrangement based on changes in the responsibilities of all parties in the arrangement. Under ASC 606, an entity recognizes revenue when its 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 arrangements that an entity determines are within the scope of ASC 606, the entity performs the following five steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine 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. As part of the accounting for contracts with customers, management develops assumptions that require judgment to determine whether promised goods and services represent distinct performance obligations and the standalone selling price for each performance obligation identified in the contract. This evaluation is subjective and requires us to make judgments about the promised goods and services and whether those goods and services are separable from other aspects of the

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contract. Further, determining the standalone selling price for performance obligations requires significant judgment, and when an observable price of a promised good or service is not readily available, we consider relevant assumptions to estimate the standalone selling price, including, as applicable, market conditions, development timelines, probabilities of technical and regulatory success and forecasted revenues.

We evaluate the performance obligations promised in the contract that are based on goods and services that will be transferred to the customer and determine whether those obligations are both (i) capable of being distinct and (ii) distinct in the context of the contract. Goods or services that meet these criteria are considered distinct performance obligations. We estimate the transaction price based on the amount expected to be received for transferring the promised goods or services in the contract. The consideration may include fixed consideration or variable consideration. At the inception of each arrangement that includes variable consideration, we evaluate the amount of potential transaction price and the likelihood that the transaction price will be received. We utilize either the most likely amount method or expected value method to estimate the amount expected to be received based on which method best predicts the amount expected to be received. The amount of variable consideration that is included in the transaction price may be constrained and is included in the transaction price only to the extent that it is probable that a significant reversal in the amount of the cumulative revenue recognized will not occur in a future period.

We apply judgment in determining whether a combined performance obligation is satisfied at a point in time or over time, and, if over time, concluding upon the appropriate method of measuring progress to be applied for purposes of recognizing revenue. We evaluate the measure of progress each reporting period and, as estimates related to the measure of progress change, related revenue recognition is adjusted accordingly. Changes in the estimated measure of progress are accounted for prospectively as a change in accounting estimate.

When two or more contracts are entered into with the same customer at or near the same time, we evaluate the contracts to determine whether the contracts should be accounted for as a single arrangement. Contracts are combined and accounted for as a single arrangement if one or more of the following criteria are met: (i) the contracts are negotiated as a package with a single commercial objective; (ii) the amount of consideration to be paid in one contract depends on the price or performance of the other contract; or (iii) the goods or services promised in the contracts (or some goods or services promised in each of the contracts) are a single performance obligation.

Upfront payments and fees are recorded as deferred revenue upon receipt or when due and may require deferral of revenue recognition to a future period until we perform our obligations under these arrangements. Where applicable, amounts are recorded as unbilled revenue when our right to consideration is unconditional. We do not assess whether a contract with a customer has a significant financing component if the expectation at contract inception is such that the period between payment by the licensees and the transfer of the promised goods or services to the licensees will be one year or less.