dnli-20251231

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

(Mark One)

For the fiscal year ended December 31, 2025

For the transition period from to

Denali Therapeutics Inc.

(Exact name of registrant as specified in its charter)

161 Oyster Point Blvd.South San Francisco, CA, 94080

(Address of principal executive offices and zip code)

(650) 866-8547

(Registrant’s telephone number, including area code)

Securities registered pursuant to Section 12(b) of the Act:

Title of each class Trading Symbol Name of each exchange on which registered

Common Stock, par value $0.01 per share DNLI The Nasdaq Global Select Market

Securities registered pursuant to Section 12(g) of the Act: None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes☒ No ☐

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Securities Exchange Act. Yes ☐No☒

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes☒ No ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes☒ No ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer”, “smaller reporting company” and "emerging growth company" in Rule 12b-2 of the Exchange Act. (Check one):

Large accelerated filer ☒ Accelerated filer ☐

Non-accelerated filer ☐ Smaller reporting company ☐

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. ☒

If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements. ☐

Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to §240.10D-1(b). ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No ☒

The aggregate market value of the common stock held by non-affiliates of the registrant as of June 30, 2025 (the last business day of the registrant’s most recently completed second fiscal quarter) was approximately $1.1 billion, based on the closing price of the registrant’s common stock, as reported by the Nasdaq Global Select Market on June 30, 2025 of $13.99 per share. Shares of the registrant’s common stock held by each executive officer, director and holder of 5% or more of the outstanding common stock have been excluded in that such persons may be deemed to be affiliates. This calculation does not reflect a determination that certain persons are affiliates of the registrant for any other purpose.

The number of outstanding shares of the registrant’s common stock as of February 20, 2026 was 158,591,491 par value $0.01 per share, outstanding. This number does not include 28,331,779 shares of common stock issuable upon the exercise of pre-funded warrants outstanding as of February 20, 2026 (which are immediately exercisable at an exercise price of $0.01 per share of common stock, subject to beneficial ownership limitations). See Note 8 — Common Stock to the registrant’s consolidated financial statements.

DOCUMENTS INCORPORATED BY REFERENCE:

Portions of the registrant’s Definitive Proxy Statement relating to the registrant’s 2026 Annual Meeting of Stockholders are incorporated by reference into Part III of this Annual Report on Form 10-K where indicated. Such Definitive Proxy Statement will be filed with the Securities and Exchange Commission within 120 days after the end of the registrant’s2025fiscal year ended December 31, 2025.

Denali Therapeutics Inc.

Annual Report on Form 10-K

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PART I

Item 1. Business 6

Item 1A. Risk Factors 63

Item 1B. Unresolved Staff Comments 119

Item 1C. Cybersecurity 120

Item 2. Properties 121

Item 3. Legal Proceedings 121

Item 4. Mine Safety Disclosures 121

PART II

Item 6. [Reserved] 124

Item 7A. Quantitative and Qualitative Disclosures About Market Risk 140

Item 8. Financial Statements and Supplementary Data 142

Item 9A. Controls and Procedures 176

Item 9B. Other Information 178

Item 9C. Disclosure Regarding Foreign Jurisdictions that Prevent Inspections 178

PART III

Item 10. Directors, Executive Officers and Corporate Governance 179

Item 11. Executive Compensation 179

Item 14. Principal Accountant Fees and Services 179

PART IV

Item 15. Exhibits and Financial Statement Schedules 180

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PART I

Special Note Regarding Forward-Looking Statements

This Annual Report on Form 10-K contains forward-looking statements. All statements other than statements of historical facts contained in this report, including statements regarding our future results of operations and financial position, business strategy, product candidates, planned preclinical studies and clinical trials, research and development costs, regulatory approvals, timing and likelihood of success, as well as plans and objectives of management for future operations, are forward-looking statements. These statements involve known and unknown risks, uncertainties and other important factors that are in some cases beyond our control and may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements.

In some cases, you can identify forward-looking statements by terms such as “may,” “will,” “should,” “would,” “expect,” “plan,” “anticipate,” “could,” “intend,” “target,” “project,” “contemplate,” “believe,” “estimate,” “predict,” “potential” or “continue” or the negative of these terms or other similar expressions. Forward-looking statements contained in this report include, but are not limited to, statements about:

•the progress, success, cost and timing of our development activities, preclinical studies and clinical trials, and in particular the development of our blood-brain barrier (“BBB”) platform technology, programs, and biomarkers, including the initiation and completion of studies or trials and related preparatory work, enrollment in such trials, the timing of when data from clinical trials will become available, the advancement of new molecule entities into clinical development and related timing, and the filing of investigational new drug applications or clinical trial applications;

•the impact of preclinical findings on our ability to achieve exposures of our product candidates that allow us to explore a robust pharmacodynamic range of these candidates in humans;

•the expected potential benefits and potential revenue resulting from strategic collaborations with third parties and our ability to attract collaborators with development, regulatory, and commercialization expertise;

•the timing or likelihood of regulatory filings and approvals;

•our ability to obtain and maintain regulatory approval of our product candidates, and any related restrictions, limitations, and/or warnings in the label of any approved product candidate;

•the extent to which any dosing limitations that we have been subject to, and/or may be subject to in the future, may affect the success of our product candidates;

•the scope of protection we are able to establish and maintain for intellectual property rights covering our product candidates and technology;

•the terms and conditions of licenses granted to us and our ability to license and/or acquire additional intellectual property relating to our product candidates and Transport Vehicle;

•our ability to obtain funding for our operations, including funding necessary to develop and commercialize our current and potential future product candidates;

•our plans and ability to establish sales, marketing, manufacturing, and distribution infrastructure to commercialize any product candidates for which we obtain approval;

•future agreements with third parties in connection with the commercialization of our product candidates;

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•the size and growth potential of the markets for our product candidates, if approved for commercial use, and our ability to serve those markets;

•the rate and degree of market acceptance of our product candidates;

•existing regulations and regulatory developments in the United States and foreign countries;

•potential claims relating to our intellectual property and third-party intellectual property;

•our ability to contract with third-party suppliers and manufacturers and their ability to perform adequately;

•our plans and ability to develop our own manufacturing facilities;

•the pricing and reimbursement of our product candidates, if approved and commercialized;

•the success of competing products or platform technologies that are or may become available;

•our ability to attract and retain key managerial, scientific, and medical personnel;

•the accuracy of our estimates regarding expenses, future revenue, capital requirements and needs for additional financing;

•our ability to enhance operational, financial, and information management systems;

•the impact of adverse economic conditions such as instability in the financial services sector, rising interest rates, rising inflation, and increased labor market competition;

•the impact of increased geopolitical uncertainty, the global pandemic, and related global economic disruptions and social conditions on our business; and

•our financial performance.

We have based these forward-looking statements largely on our current expectations and projections about our business, the industry in which we operate, and financial trends that we believe may affect our business, financial condition, results of operations and prospects, and these forward-looking statements are not guarantees of future performance or development. These forward-looking statements speak only as of the date of this report and are subject to a number of risks, uncertainties and assumptions described in the section titled “Risk Factors” and elsewhere in this report. Because forward-looking statements are inherently subject to risks and uncertainties, some of which cannot be predicted or quantified, you should not rely on these forward-looking statements as predictions of future events. The events and circumstances reflected in our forward-looking statements may not be achieved or occur and actual results could differ materially from those projected in the forward-looking statements. Except as required by applicable law, we undertake no obligation to update publicly any forward-looking statements for any reason after the date of this Annual Report on Form 10-K to conform these statements to actual results or to changes in expectations.

In addition, statements that “we believe” and similar statements reflect our beliefs and opinions on the relevant subject. These statements are based upon information available to us as of the date of this report, and while we believe such information forms a reasonable basis for such statements, such information may be limited or incomplete, and our statements should not be read to indicate that we have conducted an exhaustive inquiry into, or review of, all potentially available relevant information. These statements are inherently uncertain and you are cautioned not to unduly rely upon these statements.

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This report contains estimates, projections and other information concerning our industry, our business and the markets for our product candidates. We obtained the industry, market and similar data set forth in this report from our own internal estimates and research and from academic and industry research, publications, surveys and studies conducted by third parties, including governmental agencies. Information that is based on estimates, forecasts, projections, market research or similar methodologies is inherently subject to uncertainties and actual events or circumstances may differ materially from events and circumstances that are assumed in this information. While we believe that the data we use from third parties are reliable, we have not separately verified these data. Further, while we believe our internal research is reliable, such research has not been verified by any third party. You are cautioned not to give undue weight to any such information, projections and estimates.

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ITEM 1. BUSINESS

Overview and Strategy

Our purpose is to bring the power of biotherapeutics to the whole body, including the brain, by discovering, developing, and delivering medicines for people living with serious diseases.

Historically, the blood-brain barrier has been a major challenge to the development of medicines for diseases of the central nervous system. While the blood-brain barrier protects the brain and is essential for our survival, it also prevents the delivery of medicines to the brain in sufficient quantities to have therapeutic effect. We have invented, developed, and validated a proprietary technology, called the TransportVehicleTM ("TV"), to address the blood-brain barrier challenge and enable a new class of barrier-crossing therapeutics. The TV has a modular design enabling delivery of large molecules, i.e., enzymes, oligonucleotides, and antibodies, to all tissues of the body, including the brain, by crossing the blood-brain barrier after systemic administration. Over the last few decades, large molecule biotherapeutics have enabled medical breakthroughs in treating a wide array of serious diseases, but with very limited success in central nervous system diseases. Now, with the invention and validation of our TV technology, we are leading the field in delivering on the potential of biotherapeutics to transform the lives of individuals with neurodegenerative diseases, lysosomal storage disorders, and other serious diseases.

We are building a broad portfolio of therapeutic candidates by investing in our TV franchises, i.e., Enzyme TV ("ETV"), Oligonucleotide TV ("OTV"), and Antibody TV ("ATV"), to advance programs for rare diseases, such as lysosomal storage diseases, and common diseases, such as Alzheimer's disease and Parkinson's disease. Our most advanced TV-enabled program is tividenofusp alfa (DNL310, ETV:IDS) for the potential treatment of mucopolysaccharidosis II ("MPS II", or Hunter syndrome). Thebiologics license application ("BLA") for tividenofusp alfa is under priority review for accelerated approval by the U.S. Food and Drug Administration ("FDA"), and we have established commercial readiness in anticipation of the Prescription Drug User Fee Act (PDUFA) target action date of April 5, 2026. Our TV-enabled clinical development portfolio also includes DNL126 (ETV:SGSH) for mucopolysaccharidosis IIIA (“MPS IIIA”, or Sanfilippo syndrome type A), DNL593 (PTV:PGRN) for frontotemporal dementia-granulin (“FTD-GRN”), DNL628 (OTV:MAPT) for Alzheimer’s disease, and DNL952 (ETV:GAA) for Pompe disease. We believe the combination of a clinically-validated delivery platform and a maturing therapeutic portfolio will position us for long-term success in our goal to deliver barrier-crossing, targeted, and effective medicines.

Key elements of our strategy include:

1)Discover: Advance a new class of barrier-crossing therapeutics by leveraging our TV platforms and deep expertise in blood-brain barrier biology to enhance the delivery of biotherapeutics to the brain and throughout the body.

2)Develop: Accelerate and expand a broad portfolio of TV-based product candidates to fully unlock the potential of barrier-crossing therapeutics, applying patient-informed development and driving biomarker-guided regulatory approvals.

3)Deliver: Launch initial products targeting rare lysosomal storage diseases as a strategic foundation for expansion into common neurodegenerative conditions and other serious diseases, while building integrated capabilities for long-term growth and profitability.

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Our “D3X3” strategy reflects our next phase of execution and is anchored in our “Discover, Develop, Deliver” (D3) framework, with three-year objectives (X3) across our portfolio, as we transition from platform validation to delivery and scalable growth. Our goals are to (i) deliver two growing commercial brands, tividenofusp alfa (ETV:IDS) for Hunter syndrome and DNL126 (ETV:SGSH) for Sanfilippo syndrome type A, establishing the foundation for a durable rare disease franchise; (ii) achieve five clinical proof-of-concept readouts across our portfolio, including programs in Alzheimer’s disease (ATV:Abeta and OTV:MAPT), FTD-GRN (PTV:PGRN), Pompe disease (ETV:GAA), and Parkinson’s disease (LRRK2 inhibitor); and (iii) advance four to six additional TV-enabled programs into the clinic (Figure 1). We believe disciplined and efficient execution against these objectives will demonstrate the breadth and scalability of our TV platform, position us to deliver sustainable long-term growth, and advance our mission to unlock the full potential of biotherapeutics with the goal of transforming the lives of people living with serious diseases.

Figure 1: Denali’s D3X3 Three-Year Strategic Framework. Illustration of Denali’s evolution over time in the context of our Discover, Develop, Deliver (D3) foundation and three-year (D3X3) objectives (2026 - 2028) to deliver two growing brands, achieve five clinical proof-of-concept readouts, and advance four to six new clinical programs as we transition from platform validation to commercial delivery and scalable growth.

We expect our first potential product launches will be with tividenofusp alfa for MPS II followed by DNL126 for MPS IIIA. MPS II and MPS IIIA belong to a group of lysosomal storage diseases, which are caused by genetic mutations that lead to single-enzyme deficiencies. Lysosomal storage diseases afflict more than 30,000 individuals worldwide. About two-thirds of these diseases affect the central nervous system; however, the current standard treatment, enzyme replacement therapy, does not address central nervous system manifestations, even for the lysosomal storage diseases where enzyme replacement therapy is available. Our ETV therapeutics are designed as next-generation enzyme replacement therapies to address both central nervous system and somatic manifestations of lysosomal storage diseases. Our BLA submission for tividenofusp alfa under the accelerated approval pathway is based on alignment with the FDA that cerebrospinal fluid ("CSF") heparan sulfate may be used as a surrogate biomarker for MPS II. Likewise, given that CSF heparan sulfate is also the primary substrate in MPS IIIA, we have aligned with the FDA on an accelerated approval path for DNL126. Together, we expect these two programs to have a combined market opportunity of over $1 billion and to be the foundation of a broad commercial franchise of ETV-enabled enzyme replacement therapies with a collective market potential of over $5 billion.

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We have established commercial readiness for tividenofusp alfa including continued dialogue with advocacy groups, prescribers and payers, and building a suite of patient support services and capabilities to enable access. We have established a right-sized team in commercial and medical affairs to support tividenofusp alfa and additional ETV launches, including DNL126 (ETV:SGSH) for MPS IIIA. We include PTV:PGRN as one of our ETV franchise programs as it has a similar mechanism of action in increasing levels of deficient or missing protein to improve lysosomal function. We have an active collaboration with Takeda Pharmaceutical Company Limited ("Takeda") for the development and commercialization of TAK-594/DNL593 (PTV:PGRN) for FTD-GRN. We are initiating clinical development with DNL952 (ETV:GAA) for late-onset Pompe disease, expanding the reach of our TV platform into muscle disease. We intend to commercialize these product candidates, if approved, in key markets and/or leverage partnerships or distributors to ensure optimal access for patients. Launching in rare indications first gives us the opportunity to build and establish our own commercial organization so that we are poised for success in larger indications over time.

In parallel, we are advancing TV-enabled programs for common neurodegenerative diseases, such as Alzheimer’s disease and Parkinson's disease, which afflict over 40 million individuals worldwide and have a market potential of over $5 billion per indication. We have advanced DNL628 (OTV:MAPT) targeting tau into a Phase 1b clinical study for Alzheimer’s disease, and we plan to submit a regulatory application in the first half of 2026 to begin clinical testing of DNL921 (ATV:Abeta) targeting amyloid plaques. Amyloid plaques and tau tangles are pathological hallmarks of Alzheimer's disease. We are targeting both of these pathologies with our ATV and OTV platforms, respectively, aiming to deliver the next generation of anti-amyloid therapeutics and a potential first-in-class anti-tau therapeutic. Preclinical studies with ATV:Abeta have demonstrated potential for better efficacy and safety compared to a standard antibody, with superior plaque reduction and very low rates of amyloid related imaging abnormalities ("ARIA"). Likewise, preclinical studies with OTV:MAPT have demonstrated robust and sustained reductions of tau protein. For late-stage development and commercialization in common indications, such as Alzheimer's disease, we may plan to initially leverage strategic collaborations that contribute existing global infrastructure.

In addition to our development programs for neurodegenerative and lysosomal storage diseases, we have a robust discovery effort to further expand our portfolio and capture the full potential of our TV platform to enhance delivery of biotherapeutics to all tissues in the body. We are also pursuing opportunities of unmet need in other disease areas including oncology. For example, we have engineered a bispecific ATV:HER2 antibody and have demonstrated preclinically improved peripheral anti-tumor activity as well as enhanced brain uptake of the bispecific ATV:HER2 as compared to a non-ATV HER2 antibody. The data support the potential for ATV:HER2 to treat HER2-positive peripheral tumors and brain metastases and further validate the potential for TV applications in oncology.

Our therapeutic portfolio also includes BIIB122/DNL151 (LRRK2 inhibitor) for Parkinson's disease, a small molecule drug candidate that does not use the TV platform but is engineered with optimized chemical and physical properties to cross the blood-brain barrier. Denali has an active collaboration with Biogen Inc.’s subsidiaries, Biogen MA Inc. (“BIMA”) and Biogen International GmbH (“BIG”) (BIMA and BIG, collectively, “Biogen”) for the development and commercialization of BIIB122/DNL151. Biogen is conducting the global Phase 2b LUMA study, which is evaluating the ability of BIIB122 to slow disease progression as compared to placebo in participants with early-stage Parkinson's disease. A total of 650 participants were enrolled in LUMA and data are expected in mid-2026. In addition, Denali is conducting the complementary Phase 2a BEACON study in LRRK2-associated Parkinson's disease with the aim to generate biomarker and safety data to inform how LRRK2 inhibition may impact this disease.

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In March 2025, we officially opened our clinical biomanufacturing facility in Salt Lake City, Utah, expanding our U.S. manufacturing capabilities and strengthening supply chain control and operational efficiency. We have begun manufacturing drug supply for clinical trials to support expansion of our TV-enabled therapeutic portfolio. We employ standard antibody manufacturing processes, including Chinese hamster ovary cell culture and Protein A affinity purification, which are compatible with existing global manufacturing infrastructure and enable efficient scale-up. We expect to continue a hybrid manufacturing strategy, utilizing both internal capabilities and external contract manufacturers for additional capacity, sterile fill-finish, and oligonucleotide synthesis, as appropriate, to support our pipeline and future commercial needs.

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. Notable active arrangements include those with Biogen and Takeda as described above and Genzyme Corporation, a wholly owned subsidiary of Sanofi S.A. ("Sanofi"), for the development and commercialization of SAR443122/DNL758 (peripherally restricted small molecule RIPK1 inhibitor) in ulcerative colitis. We hold significant development and commercialization rights to all of our central nervous system programs, including the programs which are subject to our collaboration agreements with Biogen and Takeda, where we share responsibility for clinical development and share commercialization rights in the United States and China. Our costs of developing programs associated with these collaborations are largely covered through upfront payments, expected incoming milestone and royalty payments, and cost sharing. We may seek additional strategic partnering opportunities as we strive to capture the full value of our portfolio and platforms.

We are guided by the core Denali Values of trust, growth, grit and unity. Our working culture seeks to develop quality leaders, emphasize continuous growth, and promote problem-solving and invention. We strive to manage our operations in a way that is sustainable and reduces our impact on the environment, including through a Green Alternative program, which provides researchers with information on suitable alternative chemicals that have a lower environmental impact for common solvents. Additionally, several waste streams have been segregated on-site for proper disposal or recycling, such as containers, food waste, plastics, styrofoam, and glass chemical containers, to maximize recycling and composting. We also maintain an ongoing commitment to corporate governance principles, with oversight of ESG matters by Denali's Board of Directors, and strong performance orientation in our compensation program.

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Our TransportVehicleTM Platform

Historically, the blood-brain barrier has been a major challenge to the development of medicines for diseases of the central nervous system. As a tightly knit layer of endothelial cells lining the vasculature of the brain, the blood-brain barrier protects the brain from threats such as harmful substances and infections by closely regulating transport of molecules from the blood into and out of the brain. While the blood-brain barrier is essential for our survival, it also prevents the delivery of medicines to the brain in sufficient quantities to have therapeutic effect. We have pioneered and are developing a new class of biotherapeutics to directly address the blood-brain barrier challenge.

We invented, developed, and continue to optimize a proprietary technology, called the TransportVehicleTM ("TV"), to deliver our large molecule biotherapeutic candidates to the brain after systemic administration. Our research has shown that the TV platform enables efficient delivery of biotherapeutics throughout the body, including the brain and other tissues that are traditionally difficult to reach. By engaging endogenous receptor-mediated transport pathways, such as the transferrin receptor ("TfR"), the TV enhances distribution beyond the vasculature, supporting uptake in the central nervous system as well as peripheral tissues such as muscle, bone, and other organs. This whole-body delivery capability allows us to address diseases with both central and systemic manifestations using a single therapeutic approach. Our TV technology is modular and enables brain delivery of several classes of biotherapeutics including enzymes, oligonucleotides, antibodies, and other proteins (Figure 2).

Figure 2: Engineering brain delivery. Schematic of the TV platform and modalities, designed to cross the blood-brain barrier through receptor mediated transcytosis, leveraging endogenous receptors expressed on endothelial cells of the central nervous system vasculature.

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Our TV technology is differentiated from other blood-brain barrier technologies through its engineering approach, which may provide superior therapeutic efficacy, safety, and tolerability through higher stability, exposure, and biodistribution as well as the potential for lower immunogenicity of drug candidates in the brain. Compared to conventional approaches that use the Fab portion (the "arms") of a full-length antibody to bind to the targeted blood-brain barrier receptor (e.g.,TfR), we use an Fc domain (the "legs") (Figure 3). We have engineered the blood-brain barrier receptor binding site into one of the Fc's (monovalent binding) and we can optimize binding affinity (how tightly the Fc binds its blood-brain barrier receptor target) and epitope (where the Fc binds its blood-brain barrier receptor target) to enhance brain delivery and limit receptor degradation. Clinical and preclinical studies with several of our TV-enabled product candidates demonstrated high concentrations and broad distribution in all explored regions of the central nervous system and in key central nervous system cell types and showed improved pharmacodynamic effects compared to standard biotherapeutics.

We can also modify the amino acid sequences in the Fc to enable "conditional effector function", which is important for optimal activity of certain molecules, such as ATV:Abeta, that require immune cell activity for therapeutic effect. By toggling effector function "on or off", the loss of reticulocytes (immature red blood cells) can be avoided, potentially limiting anemia, which is a known liability associated with targeting TfR. Further, as the blood-brain barrier receptor binding site is a short amino acid sequence integrated into the Fc, the TV maintains high fidelity to the natural protein and does not require appended sequences, thereby improving stability and limiting risk of immunogenicity and infusion-related reactions ("IRRs"). In addition, Fc engineering enables modularity for the broadest utility to transport biologics including enzymes, oligonucleotides, and antibodies.

Figure 3: Denali’s Fc-based TV technology is modular, designed to optimize brain delivery and safety, and is highly differentiated from conventional Fab-based approaches.

Across TV modalities, we have shown in preclinical and/or clinical studies that TV enables broader brain biodistribution, enhanced target engagement, and normalization of key disease biomarkers (Figure 4). More than 200 subjects have participated in clinical studies of our TV-enabled programs and more than 11,000 doses of TV-enabled therapeutics have been administered for up to over five years (as of November 3, 2025). We achieved proof of concept with safety and pharmacokinetic and pharmacodynamic data from Phase 1/2 clinical studies in patients and healthy volunteers, as well as data from several preclinical studies in mouse and nonhuman primate models. For example, we have demonstrated the ability to correct neurodegeneration observed as substantial reduction and normalization of levels of neurofilament light chain (“NfL”), a biomarker of neuronal damage, in the Phase 1/2 study of tividenofusp alfa for MPS II as well as in multiple animal models.

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Figure 4:Left Panel: TV provides high and uniform deposition of ATV across the brain with systemic delivery; Middle Panel: TV enables sustained brain tau knockdown with OTV:MAPT systemic delivery; Right Panel: TV enables ETV:IDS to reduce serum NfL by >80%, achieving normal levels.

We believe that we can further expand our portfolio by targeting other blood-brain barrier receptors that may confer different properties from targeting TfR. For example, we are targeting CD98hc, an amino acid transporter highly expressed on the blood-brain barrier (Figure 5). Our preclinical studies have established TVCD98hc as a modular brain delivery platform with favorable kinetic, biodistribution, and safety properties distinct from previously reported blood-brain barrier platforms. We believe that the distinct properties of our two TV platforms, TVTfR and TVCD98hc may enable selection of the optimal platform for a given drug target thereby expanding our portfolio opportunities. In addition, we have developed a dual TV platform that engages both TfR and CD98hc, combining complementary brain delivery properties and providing additional flexibility to optimize brain exposure across a range of therapeutic programs.

Figure 5: TVTfR targets TfR and TVCD98hctargetsCD98hc, an amino acid transporter. Both receptors are highly expressed on the blood-brain barrier and can be utilized for brain delivery of biotherapeutics.

Our Therapeutic Portfolio

Our therapeutic portfolio (Figure 6) currently includes five clinical-stage TV-enabled programs and more than ten programs in preclinical development and spans a broad range of investigational therapies for neurodegenerative diseases, lysosomal storage disorders, and other serious diseases. In addition to our current clinical development portfolio, we expect to advance four to six new molecule entities (“NMEs”) into clinical development over the next three years beginning in 2026. We discuss our most advanced programs in further detail below.

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Figure 6: Our therapeutic portfolio is broad and diverse, spanning neurodegenerative diseases, lysosomal storage disorders, and other serious diseases that may be addressed by our TV platform for enabling and enhancing the delivery of biotherapeutics to target tissues.

Enzyme TransportVehicleTM Franchise

The Enzyme TransportVehicleTM ("ETV") franchise (Figure 7) represents our first potential commercial application of the TV platform and is designed to address significant unmet needs in lysosomal storage disorders, many of which have both central nervous system and systemic manifestations. By enabling efficient delivery of enzyme replacement therapies to the brain and throughout the body, the ETV franchise has the potential to improve upon existing standards of care that are limited by inadequate tissue distribution, and do not reach the brain in sufficient concentrations. We believe the ETV franchise offers a substantial near- and long-term commercial opportunity, supported by validated disease biology, established regulatory pathways, and the historically high success rates of approximately 80 percent of enzyme replacement therapies in rare genetic diseases.

The ETV franchise is intended to serve as the commercial and financial foundation of our business, with the anticipated launch of tividenofusp alfa for Hunter syndrome and the advancement of additional ETV programs, including DNL126 for Sanfilippo syndrome type A, DNL593 for FTD-GRN, and DNL952 for Pompe disease. Revenue generated from the ETV franchise is expected to support continued investment in our TV platform, enabling us to expand our pipeline across additional enzyme, antibody, and oligonucleotide-based therapeutics. Through this strategy, we aim to build a sustainable, revenue-generating rare disease business while funding the long-term development of our broader platform across neurodegenerative and other serious diseases.

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Figure 7: Our ETV franchise is intended to deliver the next generation of enzyme replacement therapies designed to treat central nervous system and somatic manifestations of lysosomal storage diseases and other serious genetic diseases.

ETV Clinical Programs

Tividenofusp alfa(DNL310, ETV:IDS) Enzyme Replacement Therapy Program for MPS II (Hunter Syndrome)

MPS II, also called Hunter syndrome, is a rare genetic disease that affects over2,000 individuals, primarily males, in commercially accessible geographies world-wide and leads to behavioral, cognitive, and physical symptoms ultimately resulting in shortened lifespan. MPS II is caused by mutations in the iduronate-2-sulfatase ("IDS") gene, which leads to a deficiency of the IDS enzyme responsible for the breakdown of the glycosaminoglycans ("GAGs") heparan sulfate and dermatan sulfate in lysosomes. Symptoms often begin emerging around age two and include physical complications, including organ dysfunction, joint stiffness, hearing loss and impaired growth leading to short stature, and neurocognitive symptoms with impaired development. The disease is characterized by a buildup of GAGs in lysosomes, the part of the cell that breaks down materials, including GAGs. The current standard of care enzyme replacement therapy partially treats the physical symptoms but does not cross the blood-brain barrier, and as a result, cognitive and behavioral symptoms experienced by the majority of patients with MPS II are not addressed. Therapies that address behavioral, cognitive, and somatic manifestations of the disease are one of the greatest unmet needs for this community.

Tividenofusp alfa (DNL310, ETV:IDS), composed of the IDS enzyme fused to TV, is designed to deliver IDS into cells and tissues throughout the body, including the brain by crossing the blood-brain barrier, with the goal of addressing behavioral, cognitive, and physical manifestations of Hunter syndrome (MPS II). In March 2021, the U.S. Food and Drug Administration granted Fast Track designation to tividenofusp alfa for the treatment of patients with MPS II. In May 2022, the European Medicines Agency ("EMA") granted tividenofusp alfa Priority Medicines designation. In January, 2025, the FDA granted tividenofusp alfa Breakthrough Therapy Designation for MPS II.

In September 2024, we announced a successful Type C meeting with FDA’s Center for Drug Evaluation and Research (“CDER”) providing a path to filing a BLA for accelerated approval and subsequent conversion to full approval for tividenofusp alfa based on the Phase 2/3 COMPASS study for the treatment of MPS II. Agreement was reached that a reduction in CSF heparan sulfate is reasonably likely to predict clinical benefit and can be used as a surrogate endpoint to support accelerated approval for tividenofusp alfa in MPS II.

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In May 2025, we announced that the BLA was submitted under the accelerated approval pathway and included preclinical and clinical data on biomarkers (CSF and urine heparan sulfate and neurofilament light ("NfL")), safety data, and clinical data including liver volume, hearing thresholds, cognition, and adaptive behavior. In July 2025, we announced that the FDA accepted the BLA submission and assigned a PDUFA target action date of January 5, 2026. In October 2025, we announced that the FDA had extended its review timeline of the BLA and assigned a new PDUFA target date of April 5, 2026. The extension followed our submission of updated clinical pharmacology data in response to an information request from the FDA as part of the standard review process and was not related to efficacy, safety or biomarkers. The FDA classified the submission as a Major Amendment (MA) to the BLA, which, per FDA regulations, extended the review by three months. No additional data were requested by the FDA in the MA letter. We believe that the updated information submitted in the amendment does not affect the clinical pharmacology or benefit-risk conclusions of the BLA.

Tividenofusp alfa received Rare Pediatric Disease Designation (“RPDD”) status for the treatment of Hunter syndrome in January 2019. In December 2025, we announced ongoing dialogue with the FDA related to the eligibility of tividenofusp alfa to receive a Rare Pediatric Disease Priority Review Voucher (“PRV”) upon approval. Because we submitted a filing of our intent to request a PRV after the initial BLA submission, based on discussions with the FDA, we may not be eligible to receive the PRV. Therefore, we are not including any potential future proceeds from the sale of a PRV in our financial planning. We continue to work with the FDA and the FDA will determine whether to award a PRV upon approval of tividenofusp alfa.

The Late Cycle Meeting with the FDA has been completed and labeling discussions are ongoing. We are building our launch plans in partnership with the MPS II community, and we are engaged in prelaunch activities, including continued dialogue with advocacy groups, prescribers and payers, and building a suite of patient support services and capabilities to enable access. We have built a right-sized team in commercial and medical affairs to support tividenofusp alfa and additional ETV product launches.

We are also conducting the global Phase 2/3 COMPASS study, which will support global approval. The Phase 2/3 COMPASS study is being conducted in North America, South America, and Europe. The participants are randomized 2:1 to receive either tividenofusp alfa or idursulfase, respectively. Cohort A includes children ages ≥2 to <6 years with neuronopathic disease; cohort B includes children and adults ages ≥6 to <26 without neuronopathic disease. Cohort A enrollment of a total of 44 participants was completed in December 2025, and Cohort B continues to enroll participants with non-neuronopathic MPS II.

We have previously reported interim analyses from the Phase 1/2 study, and, most recently, the primary analysis upon which the BLA was based was published in The New England Journal of Medicine in January 2026 (Muenzer et al., NEJM, 2026).

The primary objective of the Phase 1/2 study was safety and tolerability, and secondary objectives evaluated central nervous system and peripheral effects of tividenofusp alfa by measuring the GAG heparan sulfate (HS) in cerebrospinal fluid (CSF) and urine, adaptive behavior and liver volume. The study evaluated treatment in 47 ERT-naïve (n=15) and previously treated (n=32) study participants (aged 0.3–13 [median, 5] years), ranging from less severe to severe disease variants. Safety and tolerability data were consistent with previously reported results from this Phase 1/2 trial (Table 1). The most common treatment-related adverse events were infusion-related reactions, which decreased in incidence with continued use (Figure 8A). At baseline, 19% of the participants had anemia of grade 1 or higher. Decreases in the hemoglobin level were observed early with tividenofusp alfa treatment but generally returned to baseline values (Figure 8B), were clinically manageable, and did not result in discontinuation of study participation. Causes of anemia are probably multifactorial, including nutritional deficiencies, frequent phlebotomy early in the study, and possible immune effects such as the formation of antidrug antibodies.

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Table 1: Summary of Adverse Events in Phase 1/2 study of tividenofusp alfa (Muenzer et al., NEJM, 2026)

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Figure 8: Infusion-Related Reactions and Hemoglobin Levels over Time. Infusion related reactions (A) decreased in frequency and severity over time and early decreases in hemoglobin levels (B) generally returned to baseline values, were clinically manageable, and did not result in discontinuation of study participation in the Phase 1/2 study of tividenofusp alfa (Muenzer et al., NEJM, 2026).

Results from key secondary endpoints included:

•Mean CSF levels of HS, the primary substrate found in high levels in the brain of individuals with MPS II, were reduced from baseline by 91% (95% CI, 90% to 92%; N=44) at Week 24 and maintained through Week 153 (92%; 95% CI, 90% to 93%; N=16). At Week 24, 93% of study participants reached levels within the range of children without MPS II (Figure 9).

•Mean urine HS levels were reduced by 88% (95% CI, 85% to 90%; N=40) from baseline at Week 24 and maintained through Week 153 (91%; 95% CI, 87% to 94%; N=10). At Week 24, 58% of participants reached levels in the range of children without MPS II (Figure 9).

•Serum neurofilament light (NfL) chain levels, a well-established biomarker of neuronal injury and an exploratory endpoint of the study, were reduced by 21% (95% CI, 5% to 35%; N=34) from baseline at Week 49. At Week 153, NfL was reduced by 76% (95% CI, 68% to 82%; N=13), and 85% of participants reached levels within the range of children without MPS II (Figure 9).

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•Clinical results included normalization in liver volume after 24 weeks, and as shown in Figure 10, improvement in hearing thresholds across tested frequencies, and skill gains in most participants on measures of adaptive behavior and cognition.

2026 expected progress and milestones:

•Commercial launch pending approval with PDUFA target action date of April 5, 2026.

Figure 9: Treatment with tividenofusp alfa over a median duration of 2 years was associated with reductions in central nervous system and peripheral biomarkers of substrate accumulation and neuronal injury to levels within the range of unaffected children (Muenzer et al., NEJM 2026).

Figure 10: While on tividenofusp alfa, clinical outcomes showed skill gains relative to baseline on measures of adaptive behavior, cognition and hearing threshold improvement represented as pure tone average (PTA) (Muenzer et al., NEJM, 2026).

DNL126 (ETV:SGSH) Program for MPS IIIA (Sanfilippo Syndrome Type A)

MPS III, also called Sanfilippo syndrome, is a rare, genetic lysosomal storage disease that causes neurodegeneration. There are four main types of MPS III, depending on the enzyme affected. Type A is caused by genetic defects that result in reduction in the activity of N-sulfoglucosamine sulfohydrolase ("SGSH"), an enzyme responsible for degrading heparan sulfate in the lysosome. There are no approved treatments for MPS IIIA.

DNL126 (ETV:SGSH) is composed of SGSH fused to TV, which is engineered to cross the blood-brain barrier via receptor mediated transcytosis into the brain and to enable broad delivery of SGSH into cells and tissues throughout the body with the goal of treating MPS IIIA. Preclinical datademonstrate that DNL126 improved lysosomal and microglial morphology, neurodegeneration, and cognitive function in adult MPS IIIA mice. Peripheral treatment with ETV:SGSH lowered substrate accumulation (heparan sulfate) in the brain and in CSF, which was correlated with improved cognitive behavioral performance in adult MPS IIIA mice.

In January 2024, we commenced dosing of participants with MPS IIIA in a multicenter, open-label, Phase 1/2 study to assess the safety, tolerability, pharmacokinetics, pharmacodynamics, and exploratory clinical efficacy of DNL126. The core study period is 25 weeks followed by an open-label extension period through 193 weeks. In June 2024, we announced that DNL126 was selected for the FDA's Support for Clinical Trials Advancing Rare disease Therapeutics ("START") program to accelerate the development of rare disease therapeutics, and collaborative engagement has commenced to support progress to a pre-BLA meeting.

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In August 2025, we announced having reached alignment with the FDA’s CDER that cerebrospinal fluid heparan sulfate (CSF HS) may be considered a reasonably likely surrogate endpoint to predict clinical benefit and may therefore be used to support accelerated approval of DNL126 for MPS IIIA. We also announced that additional 49-week data from the ongoing open-label Phase 1/2 study were consistent with previously announced 25-week data, demonstrating a significant reduction in CSF HS from baseline, including normalization, and a safety profile that supports continued development.

The Phase 1/2 study completed enrollment of a total of 20 participants with MPS IIIA in September 2025. In February 2026, we reported preliminary results from the Phase 1/2 study at the WORLDSymposium. Preliminary data from 14 participants enrolled at the time of the clinical data cut-off (June 4, 2025) were presented, including biomarker results from the dose-finding cohorts (n=8) and safety data from the dose-finding and efficacy cohorts (n=14). Preliminary biomarker results from dose-finding cohorts showed treatment with DNL126 resulted in a mean reduction in cerebrospinal fluid heparan sulfate (CSF HS) of 80% (95% CI: 43% to 93%) and 61% in CSF GM3 (95% CI: 36% to 76%), a biomarker of lysosomal function, from baseline at Week 49 (Figure 11). Normalization of CSF HS and CSF GM3 levels was observed in three and six of seven individuals, respectively, with CSF samples available at Week 49. A mean reduction in urine HS of 83% (95% CI: 77% to 87%) from baseline was observed at Week 49, and improvement in liver volume was observed as early as Week 25 (Figure 12). Preliminary safety data from dose finding and efficacy cohorts up to the data cutoff date, including 13 of 14 participants treated for at least 24 weeks and 8 of 14 participants treated for at least 48 weeks, demonstrated that the safety profile of DNL126 is generally consistent with established enzyme replacement therapies. The most common treatment-related adverse events in the study were infusion-related reactions (Table 2).

2026 expected progress and milestones:

•Report preliminary data at WORLDSymposium (presented February 2026).

•Initiate activities to begin the Phase 3 confirmatory study.

Figure 11: Robust reductions from baseline in CSF heparan sulfate and CSF GM3 with normalization of levels in 3 and 6 of 7 participants, respectively, who had CSF samples at Week 49 after treatment with DNL126.

Figure 12:Substantial reductions from baseline in urine HS and liver volume at the first post-baseline time point where these endpoints were measured.

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Table 2: Treatment-Emergent Adverse Events (TEAEs) reported in >30% of participants (n=14) from dose-finding and efficacy cohorts as of the clinical cutoff date (June 4, 2025).

TAK-594/DNL593 (PTV:PGRN) Program for FTD-GRN

FTD is the most common form of dementia in people under 60 years of age. While the progression of symptoms varies by individual, FTD brings an inevitable decline in function together with changes in personality and social behaviors, and sometimes language and/or motor dysfunction. Mutations in the granulin ("GRN") gene, which encodes the progranulin ("PGRN") protein, generally result in reduced levels of PGRN and are among the most common genetic causes of FTD. It is estimated that FTD-GRN is 5-10% of the total FTD patient population, or more than 25,000 people worldwide. There are currently no approved medicines to stop or slow the progression of FTD or FTD-GRN.

TAK-594/DNL593 (PTV:PGRN) is an investigational, PGRN replacement therapy enabled by Denali's TV platform and designed to cross the blood-brain barrier and restore PGRN levels in the brain without interfering with normal PGRN transport and processing. As described in more detail in “Business - Licenses and Collaborations” below, we are collaborating with Takeda to co-develop and co-commercialize TAK-594/DNL593 (PTV:PGRN). Preclinical proof of concept demonstrates that PTV enhances uptake of recombinant PGRN by multiple cell types in the brain, including neurons and microglia, as compared to non-PTV PGRN. In addition, TAK-594/DNL593 rescued both neurodegeneration and microglial dysfunction in PGRN-deficient mice. Our improved mechanistic understanding of the role of PGRN in lysosomal function indicates that intravenous delivery of TAK-594/DNL593 followed by PTV-enhanced transport to the brain may be an effective therapeutic approach to increase PGRN levels in lysosomes.

Together with Takeda, we initiated a Phase 1/2 clinical trial of TAK-594/DNL593 for FTD-GRN in 2022. Results from Part A of this study evaluating TAK-594/DNL593 in healthy subjects were presented at the Alzheimer's Association International Conference in July 2023. Single doses of TAK-594/DNL593 were generally well-tolerated and resulted in substantial increases in CSF PGRN levels, suggesting that brain delivery of TAK-594/DNL593 was achieved and that TAK-594/DNL593 has the potential to address PGRN deficiency (Figure 13).

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Figure 13: Dose-dependent increase in CSF PGRN in healthy volunteers with intravenous TAK-594/DNL593.

In January 2024, Denali announced that enrollment and dosing were voluntarily paused in Part B of the Phase 1/2 study to implement protocol modifications. The pause was based on infusion-related reactions reported in two study participants, one Grade 2 and one Grade 3 in severity and both deemed serious adverse events. Both study participants’ infusion-related reactions resolved within the same day with infusion discontinuation and standard treatment measures. TAK-594/DNL593 was otherwise well-tolerated in the study, with all other adverse events reported as mild in severity. In August 2024, we announced that the protocol amendment for the Phase 1/2 study was finalized, allowing for premedication and other measures aimed at reducing the risk of infusion-related reactions, and prescreening of participants for Cohort B2 had begun. In January 2025, we announced that dosing was ongoing in the study. In February 2026, we announced that enrollment in the study is complete with a total of 40 participants with FTD-GRN enrolled.

2026 expected progress and milestones:

•Interim data from Phase 1/2 Part B study in participants with FTD-GRN.

DNL952 (ETV:GAA) for Pompe disease

Acid alpha-glucosidase ("GAA") is an enzyme that breaks down glycogen into glucose in the body's lysosomes. Pompe disease occurs due to lack of GAA enzyme activity, which leads to lysosomal glycogen accumulation and autophagic buildup resulting in cellular disruption. There are two types of Pompe disease: Infantile Onset Pompe Disease ("IOPD") and Late Onset Pompe Disease ("LOPD"). IOPD affects the heart and causes ventilatory failure leading to early death, typically before one year age if left untreated. LOPD can occur from early childhood through later decades in life and is characterized by slow progression, limb-girdle weakness leading to inability to walk, respiratory weakness leading to ventilator dependence, and central nervous system involvement. The estimated prevalence of Pompe disease is 5,000 to 10,000 people worldwide excluding India and China. The current standard of care is enzyme replacement therapy. Progressive motor weakness and respiratory failure remain unmet needs.

DNL952 (ETV:GAA) is composed of GAA fused to TV and is engineered to replace GAA in all tissues, including TfR-enabled biodistribution to muscle and brain, for the treatment of Pompe disease. In preclinical studies, compared to standard of care enzyme replacement therapies, ETV:GAA has demonstrated superior correction of glycogen load in the brain and in muscle tissue with normalization of lysosomal volume and correction of autophagy (Figure 14).

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In November 2025, we announced submission of an Investigational New Drug ("IND") application to the FDA to begin clinical studies of DNL952. In December 2025, we announced that the IND application for the Phase 1 study of DNL952 has been placed on clinical hold. The FDA requested a protocol amendment to include a lower starting dose, revised inclusion criteria, certain safety monitoring commitments, and stopping rules. These requests were related to preclinical hypersensitivity reactions observed in GAA mouse models, which are commonly observed across all GAA enzyme replacement therapies in mice. The FDA did not request additional nonclinical studies. We submitted a response to the FDA in December 2025 and announced in January 2026 that the FDA lifted the clinical hold. We are proceeding with the planned Phase 1 study. As part of our global development strategy for DNL952, we submitted a Clinical Trial Application (“CTA”) in the UK and Europe in the first quarter of 2026.

The clinical development plan for DNL952 includes an initial Phase 1 study in participants with LOPD, with planned cohorts evaluating different dose regimens of DNL952 in participants previously treated with second-generation enzyme replacement therapies, as well as optional additional cohorts, including treatment-naïve participants. The study is intended to evaluate the safety, tolerability, pharmacokinetics, and pharmacodynamics of DNL952.

2026 expected progress and milestones:

•Initiate dosing in Phase 1 clinical study of DNL952 in participants with LOPD.

Figure 14:In a rodent model of Pompe, ETV:GAA is superior to standard of care, alglucosidase alfa (Alg.) and avalglucosidase alfa-ngpt (Aval.), in correction of glycogen load in brain and in muscle (left) and superior reduction of lysosomal volume and autophagy in muscle (right).

DNL111 (ETV:Gcase) for Parkinson's disease and Gaucher disease

Glucocerebrosidase ("GCase") is an enzyme that breaks down lipids in the lysosome. Aberrant GCase substrate storage drives lysosomal dysfunction and is associated with Gaucher disease and Parkinson's disease. Homozygous loss-of-function mutations in the GBA1 gene, which encodes the GCase enzyme, leads to Gcase enzyme deficiency resulting in Gaucher disease. Gaucher disease can be associated with debilitating symptoms including a swollen belly from spleen and liver enlargement; bone pain and easily fractured and weak bones; anemia resulting in fatigue. Some people with Gaucher disease have central nervous system involvement: abnormal eye movements, muscle rigidity, swallowing difficulties, and seizures. There are an estimated 10,000 to 15,000 people with Gaucher disease worldwide (excluding China and India). Approximately 10% of all Parkinson's disease patients are heterozygous carriers of a loss-of-function GBA1 mutation, leading to lysosomal dysfunction which is strongly associated with neuroinflammation/degeneration. There are an estimated 300,000 GBA-PD patients worldwide (excluding China and India). Peripheral enzyme replacement therapy is the current standard of care for Gaucher disease, and no GBA-PD specific treatments currently approved.

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DNL111 is composed of an engineered GCase variant with improved potency, fused to TV to enable replacement of GCase in peripheral tissues and the brain via blood–brain barrier transport. In preclinical studies, ETV:GCase demonstrated enhanced substrate reduction in brain, liver, and serum compared to GCase enzyme alone. This engineered ETV:GCase approach may enable a stable, potent, brain-penetrant enzyme replacement therapy for Parkinson’s disease and Gaucher disease. DNL111 is currently in the IND-enabling stage of preclinical development.

DNL622 (ETV:IDUA) for MPS I (Hurler syndrome)

Alpha-L-iduronidase (“IDUA”) is as enzyme responsible for degrading heparan and dermatan sulfate in the lysosome. Genetic defects in the gene encoding IDUA result in deficient enzyme activity, leading to MPS I (Hurler syndrome). MPS I is characterized by alterations in the skeleton, heart, respiratory system, and brain and affects approximately 1,500 individuals worldwide.

DNL622 (ETV:IDUA) is composed of IDUA fused to TV, which is engineered to cross the blood-brain barrier via receptor-mediated transcytosis into the brain and to enable broad delivery of IDUA into cells and tissues throughout the body with the goal of treating MPS I. DNL622 is currently in the IND-enabling stage of preclinical development.

Alzheimer’s Disease Portfolio

Alzheimer’s disease represents a large and growing unmet medical need, and recent advances in biomarkers and disease-modifying therapies have increased confidence in the ability to intervene earlier and more effectively in the disease course. Despite these advances, existing antibody and nucleic acid therapeutic approaches are limited by suboptimal delivery to the brain, dose-related safety concerns, and, specific to antibodies or nucleic acid therapies respectively, difficultly engaging intracellular targets or the need for frequent or invasive administration. We believe that improved delivery of biotherapeutics across the blood-brain barrier is critical to achieving greater efficacy, improved safety, and more convenient dosing in Alzheimer’s disease, particularly as treatment paradigms shift toward earlier-stage and presymptomatic patient populations

Our approach to Alzheimer’s disease leverages the TV platform to enhance brain delivery of antibodies and oligonucleotide-based therapeutics targeting key disease-driving pathologies, including amyloid beta and tau. Our Alzheimer’s disease portfolio includes TV-enabled antibody programs designed to improve plaque clearance while potentially reducing vascular-related safety risks, as well as oligonucleotide programs intended to achieve broad and uniform distribution throughout the brain. We expect to use validated fluid and imaging biomarkers to inform patient selection, assess target engagement, and enable efficient clinical development. Through this strategy, we aim to apply the TV platform to address limitations of existing therapies and advance next-generation treatments with the potential to modify disease progression across multiple stages of Alzheimer’s disease.

DNL628 Oligonucleotide TransportVehicleTM Microtubule-Associated Protein Tau (OTV:MAPT) for Alzheimer’s disease

Oligonucleotide-based therapeutics, such as ASOs and siRNAs, are designed to modify gene expression and hold promise as therapeutics for neurological disorders. A major challenge in their development, however, is that oligonucleotides are unable to cross the blood-brain barrier on their own. Currently, oligonucleotides must be delivered directly to the central nervous system through invasive routes such as intrathecal delivery and still may not distribute uniformly throughout the brain where treatment is needed. We are using our OTV platform to enable brain delivery of oligonucleotides by crossing the blood-brain barrier following systemic administration.

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In August 2024, our preclinical research related to OTV was published in Science Translational Medicine. Denali scientists describe using OTV, which is an engineered TV conjugated to an ASO, for delivery of therapeutic molecules to the mouse and nonhuman primate brain. Our research demonstrated that OTV can successfully cross the blood-brain barrier following intravenous administration and provide cumulative and sustained knockdown of the ASO target gene expression across multiple central nervous system regions and all major cell types, including endothelial cells, neurons, astrocytes, microglia, and oligodendrocytes. In comparison to other clinically relevant ASO delivery platforms, including intrathecal delivery of a non-TV-enabled ASO, systemic OTV enabled a much more uniform ASO biodistribution profile (Figure 15) and knockdown of the target.

Figure 15: OTV demonstrated uniform ASO deposition in the nonhuman primate brain with intravenous (IV) delivery in contrast to intrathecally administered oligonucleotides, which showed limited penetration into deeper brain regions and high localized exposure in the spinal cord (left panel). OTV delivered IV showed enhanced ASO deposition in brain regions that are challenging to target including the striatum and cerebellum (right panel).

DNL628 is our TV-enabled ASO program targeting microtubule-associated protein tau (MAPT) for the treatment of Alzheimer’s disease and other tauopathies. Using the TV platform, DNL628 is engineered to facilitate efficient delivery across the blood-brain barrier, with the goal of achieving sustained reduction of tau expression in relevant neuronal populations. DNL628 is designed to address key limitations of existing tau-targeted approaches by enabling systemic administration with broad and uniform distribution throughout the brain and reducing intracellular tau that is inaccessible to antibody-based approaches.

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Preclinical studies in disease-relevant animal models expressing human tau demonstrated DNL628 achieved potent and durable reductions in MAPT RNA and tau protein levels following systemic dosing, with sustained knockdown observed well beyond the dosing period (Figure 16). These data support the potential for less frequent dosing and more uniform target engagement compared to existing approaches, which we believe may be important for achieving meaningful and durable therapeutic effects in tau-driven neurodegenerative diseases.

Figure 16: Brain MAPT RNA and tau protein knockdown (KD) persisted for >12 weeks after dosing with DNL628 in mice.

Based on these preclinical findings, we believe DNL628 has the potential to be a best-in-class tau-targeted therapy by combining potent tau reduction with improved brain distribution and a differentiated safety and convenience profile. By reducing total tau expression rather than targeting specific post-translational tau species, DNL628 is designed to broadly address tau pathology across disease stages and brain regions. The clinical development plan for DNL628 includes a Phase 1b multiple ascending dose study, which will evaluate safety, pharmacokinetics, and pharmacodynamic biomarkers of tau reduction. We expect to leverage cerebrospinal fluid and imaging biomarkers to assess target engagement and inform dose selection, with the goal of generating initial clinical biomarker data in the first half of 2027 to guide subsequent development decisions.

2026 expected progress and milestones:

•Initiate dosing in Phase 1b clinical study of DNL628 in participants with Alzheimer’s disease

DNL921 Antibody TransportVehicleTM Amyloid beta (ATV:Abeta) program for Alzheimer’s disease

The accumulation of Abeta plaque in the brain is a defining feature of Alzheimer's disease. Recently approved Abeta-directed antibody therapeutics were shown in clinical studies to reduce Abeta plaque and have modest efficacy in slowing disease progression; however, these therapies are limited by suboptimal brain distribution, dose- and exposure-related safety concerns, including amyloid-related imaging abnormalities (“ARIA”), and administration and safety monitoring requirements that may constrain broader or earlier use. As treatment paradigms increasingly shift toward earlier and potentially preclinical stages of Alzheimer’s disease, there remains a significant unmet need for therapies that can achieve more efficient and uniform brain target engagement with improved safety and dosing flexibility. Thus, there is a significant opportunity for improving the efficacy and safety of Abeta-directed antibodies, and we are using our ATV platform to develop the next generation of these therapies.

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Our ATV:Abeta program utilizes the ATV platform to enable increased brain exposure and target engagement of Abeta plaques while avoiding ARIA. In preclinical studies in mice, ATV:Abeta was shown to be superior in reducing amyloid plaque load and oligomeric Abeta load (Figure 17) compared to a conventional Abeta antibody. ATV-enabled antibodies also essentially eliminate ARIA (Figure 18). These preclinical studies provide the first mechanistic understanding of how ARIA can be prevented by virtue of ATV-enabled brain delivery of Abeta antibodies through microvessels and largely bypassing arteries, which contain the majority of the vascular amyloid that is responsible for inducing ARIA. Furthermore, as published in Pizzo et al., Science, 2025, our unique Fc engineering allows for conditional effector function through a cisLALA mutation, which preserves the ability for ATV:Abeta to engage microglia for plaque phagocytosis while mitigating TfR-related hematology liabilities such as depletion of reticulocytes (Figure 18).

Figure 17: Preclinical mouse data showing superior amyloid plaque reduction (left), superior oligomeric plaque reduction (right) with DNL921 compared to a non-TV enabled anti-Abeta

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Figure 18: Preclinical studies in a mouse model demonstrated that an ATV-enabled Abeta displays fewer to no ARIA events (left) and preservation of reticulocytes (right).

DNL921 (ATV:Abeta) is our TV-enabled antibody targeting amyloid beta and is designed to enhance brain delivery while maintaining antibody effector function in a differentiated molecular architecture. By incorporating the TV directly into the antibody structure, DNL921 is engineered to engage the transferrin receptor to facilitate receptor-mediated transport across the blood-brain barrier, enabling deeper and more uniform penetration into brain parenchyma compared to conventional antibodies. This integrated design is intended to improve plaque engagement throughout the brain while reducing perivascular localization, which we believe may contribute to vascular-related safety liabilities observed with existing therapies.

In preclinical studies, DNL921 demonstrated substantially greater amyloid plaque engagement and deeper brain penetration compared to first-generation anti-amyloid antibodies, with labeling observed across cortical and subcortical regions rather than being restricted to superficial or perivascular areas (Figure 19). In head-to-head comparisons with other transferrin receptor-enabled competitor molecules, DNL921 showed increased plaque binding efficiency at lower doses and reduced vascular engagement with higher engagement of plaque-associated microglia, which are involved in amyloid clearance (Figure 20). In preclinical studies comparing DNL921 with other TfR-based brain shuttle approaches in a humanized mouse model that allows for cross-platform comparisons (Figure 21), DNL921 demonstrated approximately two-fold higher brain concentrations. This increased brain uptake was associated with greater in vivo molecular stability, with a higher proportion of intact DNL921 maintained over time relative to Fab-based shuttle formats. In addition, DNL921 preserved effector function without inducing measurable reductions in reticulocytes, in contrast to certain TfR-binding molecules associated with hematologic effects.

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Figure 19: Whole mount imaging of brains from a mouse model of Alzheimer’s disease reveals substantially improved engagement of antibody with plaque following dosing with DNL921 compared to a non-TV enabled anti-Abeta antibody.

Figure 20: Images show increased antibody associated with amyloid plaque and less vascular staining with DNL921 compared to a non-TV enabled Abeta antibody. The increased antibody engagement leads to increased engagement with plaque-associated microglia.

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Figure 21: Studies comparing TV-enabled DN921 to molecules representing competitor TfR-based blood-brain barrier programs in a mouse model that expressed the full TfR extracellular domain reveals higher brain uptake and more intact molecule with DNL921 compared to competitor platforms.

Based on these data, we believe DNL921 has the potential to be a best-in-class amyloid beta therapy by combining efficient brain delivery, robust plaque engagement, and a differentiated safety profile that may enable lower doses, longer dosing intervals, or alternative routes of administration. The clinical development plan for DNL921 includes an initial Phase 1/1b study designed to evaluate safety, tolerability, pharmacokinetics, and biomarker-based measures of target engagement, including amyloid imaging and fluid biomarkers. The study is structured to enable rapid assessment of proof of mechanism and dose selection, with the potential to advance efficiently into later-stage clinical development. We expect to leverage validated biomarkers to inform patient selection and clinical decision making, with the goal of generating early clinical data to guide subsequent development in Alzheimer’s disease.

2026 expected progress and milestones:

•Initiate dosing in Phase 1/1b clinical study of DNL921 in healthy volunteers and participants with Alzheimer’s disease.

Our Small Molecule Programs

BIIB122/DNL151 LRRK2 Inhibitor Program for Parkinson's disease

Parkinson's disease is one of the most common brain diseases, affecting approximately 10 million people worldwide. It is considered to be a movement disorder because patients can experience tremors, slowness of movement, stiffness and difficulty with walking and balance. In addition, Parkinson's patients can have other non-motor type problems such as constipation, depression and memory loss. The Parkinson symptoms are a result of the loss of dopamine-producing cells in the brain, which is currently thought to be caused by a combination of genetic and environmental risk factors.

Mutations in the LRRK2 gene are one of the most common genetic risk factors for Parkinson's disease. LRRK2 is involved in maintaining a healthy cellular environment by regulating lysosomal function through modification of Rab proteins. Increased levels of LRRK2 kinase activity lead to lysosomal dysfunction, which is believed to contribute to neurodegeneration. Inhibition of LRRK2 activity has the potential to slow the progression of Parkinson’s disease in patients, with and without known genetic risks based on restoration of lysosomal function.

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As described in more detail in “Business - Licenses and Collaborations” below, we are collaborating with Biogen to co-develop and co-commercialize our small molecule inhibitors of LRRK2 for Parkinson's disease. BIIB122/DNL151 is the most clinically advanced small molecule inhibitor of LRRK2 currently in clinical testing for Parkinson's disease. Biogen is conducting the global Phase 2b LUMA study, which commenced in May 2022 and is evaluating the efficacy and safety of BIIB122/DNL151 as compared to placebo. Enrollment of 650 participants with early-stage Parkinson's disease was completed in March 2025.

Results from Phase 1 and Phase 1b trials of BIIB122/DNL151 in healthy volunteers and patients with Parkinson's disease, respectively, showed robust target and pathway engagement as measured by pS935 LRRK2 and pT73 Rab10 (“pRab10”), respectively. Furthermore, reduction in total LRRK2 in the CSF demonstrated central target engagement, and a dose-dependent reduction in urine of the lysosomal lipid 22:6-bis(monoacylglycerol)phosphate (“BMP”), a biomarker of lysosomal function, suggested improvement of lysosomal function. BIIB122/DNL151 was generally well tolerated across a broad range of doses for up to 28 days, the longest treatment duration in both studies.

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 Denali is operationalizing to evaluate safety and biomarkers associated with dosing BIIB122 in participants with Parkinson’s disease and confirmed pathogenic variants of LRRK2. This agreement includes committed funding of $75.0 million, of which $50.0 million has been received through 2025, and the remainder will be triggered based on 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.

In December 2024, we announced that dosing had commenced in the Phase 2a study, called BEACON, which is expected to enroll approximately 50 participants into a double-blind treatment period of three months followed by an open label extension.

2026 expected progress and milestones:

•Data from the Phase 2b LUMA study in early-stage PD in mid-2026.

Other LRRK2 Compounds

Genetic and functional studies have linked LRRK2 and other proteins that modulate lysosomal function to Crohn's disease. Excessive LRRK2 activity leads to a reduction in lysosomal function, which contributes to the inflammation and intestinal dyshomeostasis that are characteristic of this disorder. We have discovered potent and selective small molecule inhibitors of LRRK2 and have selected a lead clinical candidate (DNL975) for treatment of Crohn's disease. As described in more detail in “Business - Licenses and Collaborations” below, we are collaborating with Biogen on the Peripheral LRRK2 program.

Eclitasertib (SAR443122/DNL758) RIPK1 Inhibitor Program for Peripheral Inflammatory Diseases: UC

As part of our parallel development strategy, we have also developed peripherally-restricted RIPK1 inhibitor molecules, which are included as part of the collaboration agreement with Sanofi, described in more detail in “Business - Licenses and Collaborations” below. Sanofi is solely responsible for the development and commercialization of peripherally restricted RIPK1 inhibitors.

Sanofi is conducting a Phase 2 study of eclitasertib in patients with ulcerative colitis; data readout expected in the first half of 2026, as planned.

2026 expected progress and milestones:

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•Data from the Phase 2 UC study in the first half of 2026.

Discovery Programs

In addition to our development portfolio for neurodegenerative and lysosomal storage diseases, we have a robust discovery effort to further expand and capture the full potential of our TV platform to enhance delivery of biotherapeutics to all tissues in the body. For example, using ATV, we have engineered mono- and bispecific formats of HER2 antibodies. Human epidermal growth factor receptor 2 ("HER2") is a growth factor receptor that is over-expressed in multiple cancers, including breast, colorectal, and gastric cancer. Up to half of patients diagnosed with metastatic HER2-positive breast cancer develop brain metastases for which limited treatment options exist. In preclinical mouse studies, we have demonstrated improved anti-tumor activity of ATV-enabled HER2 antibodies in a HER2-positive peripheral tumor model. Our bispecific ATV:HER2 antibody demonstrated improved peripheral anti-tumor activity as compared to non-ATV HER2 antibodies as well as enhanced brain uptake as compared to a non-ATV HER2 antibody. The data support the potential for ATV:HER2 to treat HER2-positive peripheral tumors and brain metastases and to further validate the potential for TV applications in oncology.

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Licenses and Collaborations

Biogen License and Collaboration Agreement and Right of First Negotiation, Option and License Agreement

Overview

In October 2020, we entered into a Definitive LRRK2 Collaboration and License Agreement (“LRRK2 Agreement”) pursuant to which we granted Biogen a license to co-develop and co-commercialize our small molecule LRRK2 inhibitor program (the "LRRK2 Program"), and a Right of First Negotiation, Option and License Agreement (the "ROFN and Option Agreement"), pursuant to which we granted an option and right of first negotiation to certain of our programs utilizing our TV technology platform, including our amyloid beta program (collectively the "Biogen Collaboration Agreement"), with Biogen Inc.’s subsidiaries, Biogen MA Inc. (“BIMA”) and Biogen International GmbH (“BIG”) (BIMA and BIG, collectively, “Biogen”). 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, Option, and License Agreement (the "Biogen Amendment").

LRRK2 Agreement

The LRRK2 Agreement includes our small molecule LRRK2 inhibitors (“LRRK2 Products”) that penetrate the BBB, including DNL201 and BIIB122/DNL151, as well as those that do not penetrate the BBB, with BIIB122/DNL151 currently proceeding in clinical development.

Payments

Under the terms of the LRRK2 Agreement, Biogen paid us a $400.0 million upfront payment in October 2020. With respect to the LRRK2 Program, Biogen is required to make milestone payments up to approximately $1.125 billion upon achievement of certain development and sales milestone events. Such milestone payments include $375.0 million in development, $375.0 million upon first commercial sale, and $375.0 million in net sales-based milestones. The Biogen Amendment changed certain milestone criteria while the total amount of development, regulatory, and commercial milestones across all indications remained the same. We will share profits and losses equally with Biogen for LRRK2 Products in the United States and will share profits and losses in China with Biogen sharing 60% of such profits and losses and us sharing 40% of such profits and losses. We will be entitled to receive royalties in the high teens to low twenties percentages on net sales for LRRK2 Products outside of the United States and China. Information on cost sharing reimbursements between us and Biogen is included in this Annual Report on Form 10-K in our financial statements and the related notes and the section titled “Management’s Discussion and Analysis of Financial Condition and Results of Operations.”

License Grant to LRRK2 Program

Under the LRRK2 Agreement, we granted Biogen a co-exclusive, worldwide license under intellectual property that we control related to our LRRK2 inhibitors, including certain intellectual property licensed to us by a third party.

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Development and Commercialization of LRRK2 Program

We and Biogen are jointly developing LRRK2 Products pursuant to a clinical development plan set forth within the LRRK2 Agreement. We and Biogen share responsibility and costs for global development of LRRK2 Products pursuant to a mutually agreed development plan and budget, with Biogen funding 60% of such costs and us funding 40% of such costs. We have the ability to opt out of the development cost sharing arrangement, as further described below.

Biogen will lead commercialization activities globally for LRRK2 Products. We will co-commercialize the LRRK2 Products with Biogen in the United States and China, provided that the profit-sharing arrangement for the LRRK2 Products is still in effect, as further described below.

We may opt out of development cost sharing worldwide and upon such election, from any further profit-sharing from the LRRK2 Program. We also have the right to opt out of the profit-sharing arrangement for the LRRK2 Program or for only those LRRK2 Products that do not penetrate the BBB (“Peripheral LRRK2 Products”), in each of the United States and China. After such an opt out, we will no longer be obligated to share in the development and commercialization costs for, or be entitled to share in the applicable revenues from, such LRRK2 Program (or from the Peripheral LRRK2 Products) for such country, as applicable. If we choose to exercise our opt out rights, we will be entitled to receive tiered royalties on net sales of the applicable LRRK2 Program in the relevant country (or countries). The royalty rates for the applicable LRRK2 Program will be a percentage in the high teens to low twenties, but may increase to the low twenties to mid-twenties if we have met certain co-funding thresholds or there has been a first commercial sale at the time of our election.

LRRK2 Program Manufacturing

Biogen will be responsible for delivering all supplies for clinical trials and commercial production for LRRK2 Products, except that we will deliver such supplies until the point of transition which will be mutually agreed by us and Biogen, but in no event later than commencement of activities to support commercial launch, and in any event we retain manufacturing rights for certain independent clinical activities.

LRRK2 Program Royalty Term

For any LRRK2 Product for which Biogen is required to pay royalties, Biogen will pay us royalties on a country-by-country basis and product-by-product basis until the latest of (i) the expiration of certain patents covering the relevant product, (ii) the expiration of all regulatory exclusivity for that product in the applicable country, and (iii) an agreed period of time after the first commercial sale of that product in the applicable country. If, in a particular country, a LRRK2 Product for which Biogen is required to pay royalties is not covered by specified patent rights in that country or where generic competition exists, Biogen’s royalty obligations in the applicable country would be reduced.

Exclusivity of LRRK2 Program

During the term of the LRRK2 Agreement, neither we nor Biogen may conduct preclinical, clinical or commercial activities involving any small molecule that targets LRRK2 as its primary mechanism of action anywhere in the world, unless such molecule is included under the collaboration and only to the extent such activity is permitted under the LRRK2 Agreement or, with respect to Biogen, the molecule is an ASO product that is the subject of a collaboration between Biogen and a particular third party.

ROFN and Option Agreement

Option & ROFN Programs

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In addition to the LRRK2 Program, Biogen also received an exclusive option to license two preclinical programs enabled by our TV technology platform, including our ATV:Abeta program ("Option Programs"). In April 2023, Biogen exercised its option to develop and commercialize our ATV:Abeta program. As Biogen exercised its option with respect to the ATV:Abeta Program, we granted Biogen an exclusive, worldwide license under certain intellectual property to develop, manufacture, and commercialize products that are the subject of the ATV:Abeta Program. In August 2023, Biogen agreed to waive the remaining option upon execution of the Biogen Amendment.

In August 2023, upon execution of the Biogen Amendment, Biogen also agreed to waive its right of first negotiation on two additional TV-enabled therapeutics, which we initially granted to Biogen under the ROFN and Option Agreement.

On July 26, 2024, a Side Letter to the ROFN and Option Agreement was executed, pursuant to which, effective as of the date of the Side Letter, Biogen terminated its license to the ATV:Abeta program enabled by our TfR-targeting technology against amyloid beta for the potential treatment of Alzheimer's disease, and granted us rights to data generated during the collaboration. The side letter also effected the immediate termination of the ROFN and Option Agreement; as such, we expect to receive no future milestone or royalty payments from Biogen related to the ATV:Abeta program.

Common Stock Purchase Agreement

In August 2020, in connection with our collaboration with Biogen, we entered into a common stock purchase agreement with BIMA, pursuant to which we sold 13,310,243 shares of our common stock to BIMA for an aggregate purchase price of $465.0 million in September 2020. In connection with the sale of shares, we entered into a standstill and stock restriction agreement (the "Biogen Standstill Agreement") with Biogen, pursuant to which Biogen agreed to certain transfer and standstill restrictions, which have now expired, with the exception of certain volume limitations.

Sanofi Collaboration and License Agreement

Overview

In October 2018, we entered into the Collaboration Agreement with Genzyme Corporation, a wholly owned subsidiary of Sanofi S.A. ("Sanofi") pursuant to which certain small molecule compounds that bind to and inhibit RIPK1 (“RIPK1 Inhibitors”) contributed by Sanofi and by us will be developed and commercialized. The Sanofi Collaboration Agreement became effective in November 2018 when the requirements of the Hart-Scott-Rodino Antitrust Improvements Act of 1976 were satisfied, and included our and Sanofi’s RIPK1 Inhibitors that measurably penetrate the BBB ("CNS Products"), and our and Sanofi’s RIPK1 Inhibitors that do not measurably penetrate the BBB ("Peripheral Products").

We and Sanofi were jointly developing products containing RIPK1 Inhibitors for neurological indications, such as Alzheimer’s disease and MS, until the 2024 discontinuations of the HIMALAYA and K2 phase 2 studies evaluating SAR443820/DNL788 in participants with ALS and multiple sclerosis, respectively. On February 24, 2025, Denali and Sanofi executed a side letter terminating Sanofi's license to the CNS Products program including SAR443820/DNL788. Sanofi continues to develop eclitasertib (SAR443122/DNL758), a Peripheral Product discovered by us, and licensed to Sanofi who is leading a Phase 2 clinical trial in patients with UC.

License Grant

Under the Sanofi Collaboration Agreement, we granted Sanofi an exclusive, worldwide license under intellectual property that we control related to our RIPK1 Inhibitors, including certain intellectual property licensed to us by an academic institution.

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Payments

When the Sanofi Collaboration Agreement became effective in November 2018, Sanofi paid us $125.0 million upfront. Sanofi is required to make milestone payments totaling up to approximately $495.0 million upon achievement of certain clinical, regulatory and sales milestone events for the Peripheral Products. Such milestone payments include $120.0 million in clinical milestone payments, $175.0 million in regulatory milestone payments and $200.0 million in commercial milestone payments for Peripheral Products, as defined, that are developed and approved in the United States, Europe and in Japan for three indications. Sanofi has made payments of $35.0 million for Peripheral Product clinical milestones through December 31, 2025, and a further $65.0 million for CNS Product clinical milestones through the same date. Subsequent to the side letter executed on February 24, 2025, we expect to receive no future milestone or royalty payments from Sanofi related to the CNS Products program. We will receive variable royalties on net sales for Peripheral Products sold worldwide, each as further described below.

RIPK1 Inhibitors contributed by Sanofi and developed and commercialized under the Sanofi Collaboration Agreement will be subject to lower milestone and royalty payments to us compared to RIPK1 Inhibitors contributed by us. We will also retain responsibility for certain payment obligations under our agreement with an academic institution which licensed certain intellectual property to us that we are sublicensing to Sanofi under the Sanofi Collaboration Agreement.

Program for Development and Commercialization of Peripheral Products

Sanofi will be responsible, at its cost, for conducting activities relating to the development and commercialization of all Peripheral Products. Sanofi will lead commercialization activities globally for Peripheral Products. We will be entitled to receive tiered royalties in the low- to mid- teen percentages on net sales of Peripheral Products.

Manufacturing

Sanofi will be responsible for delivering all supplies for current and future clinical trials and commercial production for Peripheral Products. However, we retain manufacturing rights for certain independent clinical activities.

Royalty Term

For each Peripheral Product, Sanofi will pay royalties to us on a country-by-country basis until the latest of (i) the expiration of certain patents covering the relevant product, (ii) the expiration of all regulatory exclusivity for that product in the applicable country, and (iii) an agreed period of time after the first commercial sale of that product in the applicable country. If, in a particular country, a Peripheral Product is not covered by specified patent rights in that country or net sales in that country decrease below specified thresholds as a result of generic competition, Sanofi’s royalty obligations in the applicable country would be reduced or would terminate as specified in the Sanofi Collaboration Agreement.

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Exclusivity

During the term of the Sanofi Collaboration Agreement, neither we nor Sanofi may conduct IND-enabling, clinical or commercial activities involving any Peripheral Product, anywhere in the world, unless the Peripheral Product is included by us or Sanofi, as the case may be, under the collaboration and only to the extent such activity is permitted under the Sanofi Collaboration Agreement.

Termination

Each party may terminate the Sanofi Collaboration Agreement in its entirety, or with respect to a particular program, as applicable, if the other party remains in material breach of the Sanofi Collaboration Agreement following a cure period to remedy the material breach. After giving a specified amount of prior notice to us, Sanofi may terminate the Sanofi Collaboration Agreement for convenience in its entirety, with respect to any particular program, or with respect to one or more specified regions of the world. Sanofi may also terminate the Sanofi Collaboration Agreement with respect to any program or a particular RIPK1 Inhibitor if a material safety event has occurred and cessation of all development and commercialization of all RIPK1 Inhibitors in the affected program or the affected RIPK1 Inhibitor is recommended. We and Sanofi may each terminate the Sanofi Collaboration Agreement in its entirety if the other party is declared insolvent or in similar financial distress or if, subject to a specified cure period, the other party challenges any patents licensed to it under the Sanofi Collaboration Agreement.

Following any termination of the Sanofi Collaboration Agreement with respect to a particular program or a particular region (or regions) of the world or termination of the Sanofi Collaboration Agreement in its entirety, our rights to each of our RIPK1 Inhibitors that were licensed to Sanofi will revert to us. Sanofi will conduct certain development, manufacturing and commercialization activities on a transitional basis following termination of the Sanofi Collaboration Agreement, as outlined in the Sanofi Collaboration Agreement or agreed by Sanofi, depending upon the basis for the applicable termination.

If the Sanofi Collaboration Agreement is terminated for any reason other than by Sanofi for our material uncured breach, our insolvency or our challenge to any of the patents licensed to us by Sanofi, Sanofi will grant us an exclusive license to certain intellectual property controlled by Sanofi with respect to such RIPK1 Inhibitors (which could be subject to low single digit royalties payable to Sanofi).

Takeda Option and Collaboration Agreement

Overview

In January 2018, we entered into a Collaboration Agreement ("Takeda Collaboration Agreement") with Takeda Pharmaceutical Company Limited ("Takeda"), pursuant to which we granted Takeda an option with respect to our ATV:BACE1/Tau, ATV:TREM2 and PTV:PGRN programs. Takeda paid us a $40.0 million upfront payment related to the collaboration, and an additional $110.0 million under a share purchase agreement in February 2018. The Takeda Collaboration Agreement became effective in February 2018, following satisfaction of certain requirements of the Hart-Scott-Rodino Antitrust Improvements Act of 1976. In February 2019, we amended the agreement to replace the ATV:BACE1/Tau program with the ATV:Tau program and in March 2022, the parties mutually agreed to terminate activity on the ATV:Tau program over which Takeda had its option to develop and commercialize jointly with the Company. Takeda exercised its option for the PTV:PGRN program in November 2021. Takeda exercised its option for the ATV:TREM2 program in December 2021. In February 2025, after mutual agreement to discontinue preclinical activities on ATV:TREM2, Takeda delivered notice of its election to terminate the ATV:TREM2 program on February 26, 2025, as per the terms of the Takeda Collaboration Agreement. The ATV:TREM2 program termination became effective 60 days following the notice date.

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Research Phase and Takeda’s Option

Under the Takeda Collaboration Agreement we were responsible, at our cost, for conducting activities relating to pre-IND development of biologic products directed to the identified targets and enabled by our TV technology targeting TfR during the applicable option period. The option period continued for each target until the first biologic product candidate directed to the relevant target was IND-ready or about five years after selection of the target, whichever was earlier.

Takeda was obligated to pay us up to an aggregate of $25.0 million with respect to each of the programs under the Takeda Collaboration Agreement directed to a target and based upon the achievement of certain preclinical milestone events, up to $55.0 million in total after the ATV:Tau program termination, all of which was earned and received as of September 30, 2022.

Collaboration Activities Following Takeda’s Option Exercise

Subsequent to Takeda exercising its option with respect to a particular target and collaboration program (i.e., the biologic products directed to the target for which Takeda has exercised its option), Takeda has the right to develop and commercialize, jointly with us, a specified number of biologic products enabled by our TV technology that were developed during the option period and which are directed to the relevant target, and we are obligated to grant to Takeda a co-exclusive license under the intellectual property we control related to those biologic products.

Takeda was obligated to pay us a $5.0 million option fee for each target for which Takeda exercised its option, and we received fees totaling $10.0 million from Takeda in 2021 for option exercise payments for the PTV:PGRN and ATV:TREM2 programs.

Subsequent to the ATV:TREM2 termination, Takeda may be obligated to pay us milestones related to the PTV:PGRN program, including up to $140.0 million upon achievement of certain clinical milestone events and up to $100.0 million in regulatory milestone events relating to receipt of regulatory approval in the United States, certain European countries and Japan. Further, Takeda may also be obligated to pay us up to $75.0 million upon achievement of a certain sales-based milestone.

Further, we and Takeda share equally the development and commercialization costs, and, if applicable, the profits, for the PTV:PGRN program. However, we may elect not to continue sharing development and commercialization costs, or Takeda may elect to terminate our cost-profit sharing rights and obligations if, following notice from Takeda and a cure period, we fail to satisfy our cost sharing obligations. After such an election by us or termination by Takeda becomes effective, we will no longer be obligated to share in the development and commercialization costs for the PTV:PGRN program, and we will not share in any profits from that program. Instead, we will be entitled to receive tiered royalties. The royalty rates will be in the low- to mid-teen percentages on net sales, or low- to high-teen percentages on net sales if we have met a certain co-funding threshold at the time of our election to opt out of co-development or Takeda’s termination of our cost-profit sharing rights and obligations, and, in each case, these royalty rates will be subject to certain reductions specified in the Takeda Collaboration Agreement. Takeda will pay these royalties to us, on a country-by-country basis, until the latest of (i) the expiration of certain patents covering the biologic product, (ii) the expiration of all regulatory exclusivity for that biologic product, and (iii) an agreed period of time after the first commercial sale of that biologic product in the applicable country, unless biosimilar competition in excess of a significant level specified in the Takeda Collaboration Agreement occurs earlier, in which case Takeda’s royalty obligations in the applicable country would terminate.

For the PTV:PGRN program for which we are sharing costs and profits with Takeda, we will lead the conduct of clinical activities for each indication up to the first trial with a clinical outcomes-based efficacy endpoint, and Takeda will lead the conduct of all subsequent clinical activities for that indication. We and Takeda will jointly commercialize biologic product(s) included in the PTV:PGRN program in the United States and China. Takeda will lead commercialization activities in the United States and China and will solely conduct commercialization activities in all other countries.

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We have the right to lead all manufacturing activities for the PTV:PGRN program.

Information on cost sharing reimbursements between us and Takeda is included in this Annual Report on Form 10-K in our financial statements and the related notes and the section titled “Management’s Discussion and Analysis of Financial Condition and Results of Operations.”

Exclusivity

Unless the Takeda Collaboration Agreement is terminated earlier, until expiration of an agreed period of time after the first regulatory approval in the United States or Europe of a biologic product within the PTV:PGRN program, neither party may conduct clinical or commercial activities involving antibodies or protein-based therapeutic products directed to the same target (or in the case of a bi-specific program, the same combination of targets) that have an intended therapeutic effect in diseases and conditions of the CNS (including lysosomal storage diseases), except to the extent permitted under the Takeda Collaboration Agreement.

Termination

Each party may terminate the Takeda Collaboration Agreement in its entirety, or with respect to a particular collaboration program, as applicable, if the other party remains in material breach of the Takeda Collaboration Agreement following a cure period to remedy the material breach. Takeda may terminate the Takeda Collaboration Agreement in its entirety or with respect to any particular collaboration program, for convenience and after giving a specified amount of prior notice to us. Takeda may also terminate the Takeda Collaboration Agreement with respect to any collaboration program if the joint steering committee established under the Takeda Collaboration Agreement unanimously agrees that a material safety event has occurred with respect to the applicable collaboration program. We may terminate the Takeda Collaboration Agreement with respect to a particular collaboration program if Takeda fails to conduct material development and commercial activities for a specified period of time with respect to a collaboration program, unless Takeda cures such failure within a certain period of time. We and Takeda may each terminate the Takeda Collaboration Agreement in its entirety if the other party is declared insolvent or in similar financial distress or if, subject to a specified cure period, the other party challenges any patents licensed to it under the Takeda Collaboration Agreement.

Following any termination of the Takeda Collaboration Agreement with respect to a particular collaboration program or the Takeda Collaboration Agreement in its entirety, our rights to each terminated collaboration program will revert to us, Takeda will grant us a license to intellectual property owned by Takeda with respect to such collaboration program (which could be subject to certain royalty payments that would be negotiated at the time of such a termination) and, unless the termination was by Takeda on the basis of a material safety event, Takeda will conduct certain development, manufacturing and commercialization wind-down activities.

Common Stock Purchase Agreement

Pursuant to the terms of the Takeda Collaboration Agreement, we entered into a common stock purchase agreement with Takeda in January 2018, pursuant to which we sold 4,214,559 shares of our common stock (the “Shares”) to Takeda for an aggregate purchase price of $110.0 million. We closed the sale to Takeda in February 2018.

At closing, we also entered into a standstill and stock restriction agreement (the “Takeda Standstill Agreement”) with Takeda. Pursuant to the terms of the Takeda Standstill Agreement, Takeda agreed to certain transfer and standstill restrictions for a specified period of time following the closing of the sale, which have now expired. Takeda remains entitled to certain demand registration rights with respect to the Shares following termination of the transfer restrictions if the Shares cannot be resold without restriction pursuant to Rule 144 promulgated under the Securities Act of 1933, as amended (the "Securities Act").

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F-star License and Collaboration Agreement

Overview

In August 2016, we entered into a License and Collaboration Agreement (“F-star Collaboration Agreement”) with F-star Gamma Limited (“F-star Gamma”), F-star Biotechnologische Forschungs-und Entwicklungsges m.b.H ("F-star GmbH") and F-star Biotechnology Limited ("F-star Ltd") (collectively "F-star"). The goal of the collaboration was the development of certain constant Fc domains of an antibody with non-native antigen binding activity, or Fcabs, to enhance delivery of therapeutics across the BBB into the brain. The collaboration was designed to leverage F-star’s modular antibody technology and our expertise in the development of therapies for neurodegenerative diseases. The agreement included the purchase of an option for $0.5 million to acquire all outstanding shares pursuant to a pre-negotiated buy-out option agreement. We exercised this buy-out option in May 2018 and entered into a Share Purchase Agreement with the shareholders of F-star Gamma and Shareholder Representative Services LLC (the "Acquisition").

As a result of the Acquisition, F-star Gamma became a wholly-owned subsidiary of the Company and we changed the entity’s name to Denali BBB Holding Limited. In addition, we became a direct licensee of certain intellectual property of F-star Ltd (by way of the Company’s assumption of F-star Gamma’s license agreement with F-star Ltd, dated August 24, 2016, (the “F-star Gamma License”)). We made initial exercise payments under the Purchase Agreement and the F-star Gamma License of $18.0 million in the aggregate, less the net liabilities of F-star Gamma, which were approximately $0.2 million. In addition, we are required to make contingent payments, to F-star Ltd and the former shareholders of F-star Gamma, up to a maximum amount following completion of the research phase of the F-star collaboration of $243.0 million in the aggregate upon the achievement of certain defined preclinical, clinical, regulatory and commercial milestones. These include up to $3.0 million in preclinical contingent payments, $30.0 million in clinical contingent payments, $60.0 million in regulatory contingent payments, including $36.0 million due upon regulatory approval of tividenofusp alfa in the United States, and $150.0 million in commercial contingent payments. We have made payments of $49.8 million through December 31, 2025 in the aggregate consisting of up-front, preclinical and clinical contingent consideration.

Under the terms of the original F-star Collaboration Agreement, we could nominate up to three Fcab targets (“Accepted Fcab Targets”) within the first three years of the date of the F-star Collaboration Agreement. Upon entering into the F-star Collaboration Agreement, we had selected TfR as the first Accepted Fcab Target and paid F-star Gamma an upfront fee of $5.5 million, which included selection of the first Accepted Fcab Target. In May 2018, we exercised our right to nominate two additional Fcab Targets and identified CD98 as the second Accepted Fcab Target. We made a one-time payment for the two additional Accepted Fcab Targets of, in the aggregate, $6.0 million and extended the time period for our selection of the third Accepted Fcab Target until approximately the fourth anniversary of the date of the original F-star Collaboration Agreement. We did not identify a third Fcab Target. We were also responsible for certain research costs incurred by F-star Ltd in conducting activities under an agreed development plan for each Fcab, for up to 24 months after the target Fcab is accepted. In July 2021, we executed a side letter to our agreements with F-star which confirmed the completion of the research services performed by F-star Ltd that were funded by us.

Genentech Exclusive License Agreement

In June 2016, we entered into an exclusive license agreement with Genentech, Inc. (“Genentech”). The agreement gives us access to Genentech’s LRRK2 inhibitor small molecule program for Parkinson’s disease. Under the agreement, Genentech granted us (i) an exclusive, worldwide, sublicensable license under Genentech’s rights to certain patents and patent applications directed to small molecule compounds which bind to and inhibit LRRK2 and (ii) a non-exclusive, worldwide, sublicensable license to certain related know-how, in each case, to develop and commercialize certain compounds and licensed products incorporating any such compound. We are obligated to use commercially reasonable efforts during the first three years of the agreement to research, develop and commercialize at least one licensed product.

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Our financial obligations upon entering the agreement with Genentech included an upfront payment of $8.5 million and a technology transfer fee of $1.5 million. In addition, we may owe Genentech milestone payments upon the achievement of certain development, regulatory and commercial milestones, up to a maximum of $315.0 million in the aggregate, which are subject to equal cost sharing with Biogen since execution of the Biogen Collaboration Agreement. These milestones include up to $37.5 million in clinical milestone payments, $102.5 million in regulatory milestone payments and $175.0 million in commercial milestone payments. We have made milestone payments to Genentech of $15.0 million through December 31, 2025.

In addition, we are obligated to pay royalties on net sales of licensed products ranging from low to high single-digit percentages, with the exact royalty rate dependent on various factors, including (i) whether the compound incorporated in the relevant licensed product is a Genentech-provided compound or a compound acquired or developed by us, (ii) the date a compound was first discovered, derived or optimized by us, (iii) the existence of patent rights covering the relevant licensed product in the relevant country, (iv) the existence of orphan drug exclusivity covering a licensed product that is a Genentech-provided compound and (v) the level of annual net sales of the relevant licensed product. We also have the right to credit a certain amount of third-party royalty and milestone payments against royalty and milestone payments owed to Genentech, but such credit cannot reduce our royalty obligation to Genentech by more than fifty percent. Our royalty payment obligations will expire on a country-by-country and licensed product-by-licensed product basis upon the later of (a) ten years after the first commercial sale of such licensed product in such country or (b) the expiration of the last valid claim of a licensed patent covering such licensed product in such country. If one of our licensed products incorporates a compound provided to us by Genentech, has orphan drug exclusivity, and is not covered by a valid claim of a licensed patent, we must pay royalties on net sales of such licensed products on a country-by-country and licensed product-by-licensed product basis until such orphan drug exclusivity in such country expires, but our obligation to pay these royalties may be eliminated or reduced if there is a clinically superior product marketed in such country. Under the terms of our LRRK2 Agreement with Biogen, Biogen is responsible for 50% of any payment obligation to Genentech under this agreement accruing after October 2020.

Unless earlier terminated, our agreement with Genentech will continue in effect until all of our royalty and milestone payment obligations to Genentech expire. Following expiration of the agreement, we will retain our licenses under the intellectual property Genentech licensed to us on a non-exclusive, royalty-free basis. Genentech may terminate the agreement if we challenge any of the patent rights licensed to us by Genentech, or if we materially breach the agreement, subject to specified notice and cure provisions, or enter into bankruptcy or insolvency proceedings. If Genentech terminates the agreement for our material breach, bankruptcy or insolvency after we have made a milestone payment to Genentech, then we are obligated to grant to Genentech an exclusive right of first negotiation with respect to certain of our patents, know-how and regulatory filings directed to Genentech-provided compounds. We do not have the right to terminate the agreement without cause, but may terminate the agreement for Genentech’s material breach, subject to specified notice and cure provisions.

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Royalty Pharma Funding Agreement

In December 2025, we entered into a synthetic royalty funding agreement (the “Royalty Agreement”) with Royalty Pharma plc (“Royalty Pharma”). Pursuant to the Royalty Agreement, Royalty Pharma has agreed to provide us with up to $275.0 million in funding in exchange for a 9.25% royalty on future net sales of tividenofusp alfa. The transaction is subject to various closing conditions, including our achieving U.S. Food and Drug and Administration (FDA) accelerated approval of tividenofusp alfa on or before June 30, 2026. At the closing, Royalty Pharma will make an initial payment of $200.0 million. We will receive an additional payment of $75.0 million upon approval of tividenofusp alfa by the European Medicines Agency (EMA) on or before December 31, 2029. The royalty payments to Royalty Pharma will cease upon reaching a multiple of 3.0x, or 2.5x if achieved by the first quarter of 2039. We will retain all worldwide development and commercialization rights to tividenofusp alfa.

Manufacturing

We believe it is important to our business success to have a reliable, high-quality drug supply chain to support our preclinical and clinical development activities and, if approved, the commercialization of our product candidates. We currently rely on third-party contract development and manufacturing organizations (“CDMOs”) to manufacture and supply preclinical and clinical materials used in the development of our product candidates, and we have established relationships with several CDMOs, including Lonza Sales AG (“Lonza”), which provides development and manufacturing services with respect to certain of our biologic products on a fee-for-service basis. As we mature as a company and advance product candidates toward commercialization, securing and maintaining reliable, high-quality drug supply chains for each product candidate will be critical. We have established a third-party supply chain for tividenofusp alfa and, if approved for the treatment of Hunter syndrome, we plan to continue to rely on third-party contract manufacturers for its commercial supply.

Over time, we intend to complement our use of third-party manufacturers by selectively developing internal manufacturing capabilities, including for commercial supply, to support the advancement and commercialization of our product candidates.

In early 2025, we commenced operations at our clinical manufacturing site in Salt Lake City, Utah, expanding our clinical manufacturing capabilities for biologic therapeutics, including the manufacture of materials for toxicology studies and drug substance for human clinical studies. This facility represents an initial step in building internal manufacturing capabilities, with the goal of increasing flexibility and speed in advancing new investigational therapies into clinical trials.

Commercialization Plan

We do not currently have any approved drugs. The PDUFA date for our lead asset, tividenofusp alfa, is currently April 5, 2026. With this timeline in mind, over the course of 2025 we invested in building right-sized marketing, product distribution, and sales capabilities for the U.S. market. As of the date of this filing, we have established our U.S. commercial infrastructure to support a potential commercial launch following the PDUFA date. We expect to continue to refine these capabilities through and following launch, including distribution planning and logistics, to support the U.S. launch of tividenofusp alfa. In parallel, we are engaging in discussions with potential regional commercial partners regarding possible paths for selective expansion into certain markets outside the United States, subject to applicable regulatory requirements.

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Our vision is to become a fully integrated, independent global leader in delivering the power of biotherapeutics to the whole body, including the brain, transforming the lives of people living with serious diseases. We apply our capabilities in discovery, development, manufacturing, and commercial in order to optimize speed, quality, and patient access to our medicines. We look to grow strategically both in terms of therapeutic areas of high unmet need, starting with lysosomal storage diseases and expanding into large neurodegenerative disorders and other serious diseases, as well as from a geographic perspective, with an initial focus on building a commercial presence in the United States and the European Union ("EU"), and establishing a network of specialized regional partners to access other major markets.

For programs covered by collaboration agreements (including those with Takeda, Sanofi, and Biogen), we expect to commercialize only in certain geographies, as defined by the terms of the agreements with the counterpart, and rely on our partners to provide commercialization infrastructure for the rest of the world.

Competition

The biotechnology and pharmaceutical industries, including in the neurodegenerative disease field, are characterized by rapidly advancing technologies, strong competition and an emphasis on intellectual property. We believe that the key competitive factors affecting the success of any of our product candidates will include efficacy, safety profile, method of administration, cost, level of promotional activity and intellectual property protection.

Our product candidates will compete with current therapies approved for the treatment of neurodegenerative diseases, which to date have been primarily targeted at treating the symptoms of such diseases rather than halting or slowing the progression of the disease. However, in addition to such currently approved therapies, we believe that our product candidates, if approved, may also compete with other potential therapies intended to halt or slow the progression of neurodegenerative disease that are being developed by a number of companies and institutions, including but not limited to:

•Alzheimer’s Disease: Treatments currently approved in some geographies for Alzheimer’s Disease include the amyloid beta-directed antibody therapies ADUHELM (Biogen), LEQEMBI (Eisai/Biogen), and KISLUNA (Eli Lilly). Additionally, potentially disease modifying therapeutics are being developed by several large and specialty pharmaceutical and biotechnology companies, including Biogen/lonis, Arrowhead, Eli Lilly (including Prevail Therapeutics, its wholly owned subsidiary), Roche (including Genentech, its wholly owned subsidiary), AbbVie, Bristol Myers Squibb, Prothena, Regeneron, Alnylam, Eisai, and BioArctic in various stages of development.

•Parkinson’s Disease: Potentially disease modifying therapeutics are being developed by several large and specialty pharmaceutical and biotechnology companies, including Roche/Prothena (including Genentech, its wholly owned subsidiary), Ionis, Eli Lilly (including Prevail Therapeutics, its wholly owned subsidiary), AstraZeneca, Takeda, Oncodesign/Servier, Neuron23 and AbbVie in various stages of development.

•FTD-GRN: Potentially disease modifying therapeutics are being developed by several large and specialty pharmaceutical and biotechnology companies, including GSK/Alector, Eli Lilly (including Prevail Therapeutics, its wholly owned subsidiary), Passage Bio, AviadoBio, Vesperbio, Arkuda Therapeutics, and Orchard Therapeutics in various stages of development.

•Lysosomal storage diseases: The currently approved treatments for lysosomal storage diseases are conventional enzyme-based therapies. Various BBB-penetrant and direct to CNS delivered ERTs and gene therapies are being developed by several large and specialty pharmaceutical and biotechnology companies, including JCR Pharmaceuticals, RegenxBio, Kyowa Kirin/Orchard Therapeutics, and Ultragenyx, and are in various stages of development.

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In addition, companies are developing technologies that would compete directly with our TV technology. These include several large and specialty pharmaceutical and biotechnology companies developing BBB delivery technologies that utilize RMT, including JCR Pharmaceuticals, Roche (including Genentech, its wholly owned subsidiary), Eli Lilly (including Prevail Therapeutics, its wholly owned subsidiary), Abbvie, Regeneron, BioArctic, Alector, Bicycle Therapeutics, Ossianix, Vect-Horus, Sanofi, and ABL Bio, among others.

Intellectual Property

Our intellectual property is critical to our business and we strive to protect it, including by obtaining and maintaining patent protection in the United States and internationally for our product candidates, novel biological discoveries and TV platform, including new targets and applications, and other inventions that are important to our business. We also rely on trademarks, trade secrets, know-how, continuing technological invention and licensing opportunities to develop and maintain our proprietary position.

As of December 31, 2025, our owned and licensed patent portfolio includes over 1,600 patents and patent applications, including over 30 licensed U.S. issued patents and 40 owned U.S. issued patents, covering certain aspects of our proprietary technology, our product candidates, and related inventions and improvements. The patent portfolio also includes over 500 licensed patents issued in jurisdictions outside of the United States, and over 950 owned patents and patent applications pending in jurisdictions outside of the United States that, in many cases, are counterparts to the foregoing U.S. patents and patent applications. For our product candidates and our TV platform, we generally pursue or in-license patent protection covering compositions of matter, methods of use, and manufacture.

TV Platform

We own 10 patent families related to our TV platform. These include a family directed to the composition and sequences of our TfR-binding TVs, the earliest of which are expected to expire in 2038, not including any patent term adjustments and any patent term extensions. We also have 7 issued U.S. patents, which are also expected to expire in 2038, not including any patent term adjustments and any patent term extensions, as well as pending patent applications, to other TV platform. Other families related to TV platform, if issued, are expected to expire in 2038 or later, all not including any patent term adjustments and any patent term extensions. In addition, we license multiple patent families from F-star, the earliest issued patents of which are expected to expire in 2026, not including any patent term adjustments and any patent term extensions.

ETV Platform and Programs

We own 12 patent families directed to our ETV platform and related products, including ETV:IDS, ETV:SGSH, ETV:GAA, ETV:Gcase, and ETV:IDUA. This includes 1 issued U.S. patent, which is expected to expire in 2038, not including any patent term adjustments and any patent term extensions, directed to the composition of matter of our ETV:IDS molecules, including DNL310. We also own 5 additional patent families directed to various aspects of our DNL310 program, which if issued, are expected to expire in 2039 or later, all not including any patent term adjustments and any patent term extensions. Of the 12 patent families, 3 families relate to the composition of matter of our ETV:SGSH structures, including DNL126. This includes 1 issued U.S. patent, which is expected to expire in 2041, not including any patent term adjustments and any patent term extensions. Any patents issuing from these families are expected to expire between 2039 and 2046, respectively, not including any patent term adjustments and any patent term extensions. Of the 12 patent families, 2 families relate to the composition of matter of our ETV:GAA structures, including DNL952. This includes 1 issued U.S. patent, which is expected to expire in 2044, not including any patent term adjustments and any patent term extensions.

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PTV:PGRN Program

We own 4 patent families directed to our PTV:PGRN program. This includes 1 issued U.S. patent, which is expected to expire in 2040, not including any patent term adjustments and any patent term extensions, directed to the composition of matter of our PTV:PGRN molecules, including TAK-594/DNL593. We also own an additional patent family directed to the composition of matter of our PTV:PGRN structures, including TAK-594/DNL593, the earliest of which are expected to expire in 2039, not including any patent term adjustments and any patent term extensions. We also own additional patent families directed to various aspects of our TAK-594/DNL593 program, which, if issued, are expected to expire in 2039 or later, all not including any patent term adjustments and any patent term extensions. Our PTV:PGRN program is subject to our Takeda collaboration.

Oligonucleotide Transport Vehicle Platform and Programs

We own 7 patent families directed to our OTV platform, including OTV:MAPT and OTV:SNCA. These families are directed to compositions and methods of use of our OTVs, including DNL628 (OTV:MAPT) and DNL422(OTV:SNCA), and if issued, are expected to expire between 2042 and 2045, not including any patent term adjustments and any patent term extensions.

LRRK2 Inhibitor Program

Our LRRK2 program is subject to our collaboration agreement with Biogen. For this program, we license multiple patent families from Genentech directed to, among other things, DNL201, BIIB122/DNL151 and other related compounds, which are expected to expire in 2031, not including any patent term adjustments and any patent term extensions. Furthermore, we own additional patent families that have projected expiration dates in 2038 or later, not accounting for any patent term adjustments and any patent term extensions, related to the LRRK2 program. We also own a patent family that includes 3 issued U.S. patents, which are expected to expire in 2037, not including any patent term adjustments and any patent term extensions, directed to the composition of matter of BIIB122/DNL151 and methods of treatment using BIIB122/DNL151, respectively, as well as pending patent applications and granted patents in jurisdictions outside the U.S.

RIPK1 Inhibitor Program

Our RIPK1 program is subject to our collaboration agreement with Sanofi. We own 6 patent families directed to our RIPK1 inhibitor program. These include 13 issued U.S. patents, including one directed to the composition of matter of eclitasertib (SAR443122/DNL758), which is expected to expire in 2037, not including any patent term adjustments and any patent term extensions.

ATV:Abeta Program

We own 4 patent families directed to our ATV:Abeta program. This includes a family directed to our composition of matter of DNL921, which is expected to expire in 2046, not accounting for any patent term adjustments and any patent term extensions.

We cannot guarantee that our owned and licensed pending patent applications, or any patent applications that we may in the future file or license from third parties, will result in the issuance of patents. We also cannot predict the scope of claims that may be allowed or enforced in our patents. In addition, the coverage claimed in a patent application can be significantly reduced before the patent is issued, and its scope can be reinterpreted after issuance. Consequently, we may not obtain or maintain adequate patent protection for any of our programs and product candidates. For more information regarding the risks related to our intellectual property, see "Risk Factors - Risks Related to Our Intellectual Property."

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The term of individual patents depends upon the legal term of the patents in the countries in which they are obtained. In most countries in which we file, the patent term is 20 years from the earliest date of filing a non-provisional patent application. In the United States, the patent term of a patent that covers an FDA-approved drug may also be eligible for patent term extension, which permits patent term restoration as compensation for the patent term lost during the FDA regulatory review process. The Hatch-Waxman Act permits a patent term extension of up to five years beyond the expiration of the patent. Similar provisions are available in Europe and other foreign jurisdictions to extend the term of a patent that covers an approved drug. In the future, if and when our products receive FDA approval, we expect to apply for patent term extensions on patents covering those products. We plan to seek patent term extensions to any of our issued patents in any jurisdiction where these are available, however there is no guarantee that the applicable authorities, including the FDA in the United States, will agree with our assessment of whether such extensions should be granted, and if granted, the length of such extensions. For more information regarding the risks related to our intellectual property, see "Risk Factors - Risks Related to Our Intellectual Property."

In addition to patent protection, we also rely on trademark registration, trade secrets, know how, other proprietary information and continuing technological invention to develop and maintain our competitive position. We seek to protect and maintain the confidentiality of proprietary information to protect aspects of our business that are not amenable to, or that we do not consider appropriate for, patent protection. Although we take steps to protect our proprietary information and trade secrets, including through contractual means with our employees and consultants, third parties may independently develop substantially equivalent proprietary information and techniques or otherwise gain access to our trade secrets or disclose our technology. Thus, we may not be able to meaningfully protect our trade secrets. It is our policy to require our employees, consultants, outside scientific collaborators, sponsored researchers and other advisors to execute confidentiality agreements upon the commencement of employment or consulting relationships with us. These agreements provide that all confidential information concerning our business or financial affairs developed or made known to the individual during the course of the individual’s relationship with us is to be kept confidential and not disclosed to third parties except in specific circumstances. Our agreements with employees also provide that all inventions conceived by the employee in the course of employment with us or from the employee’s use of our confidential information are our exclusive property. However, such confidentiality agreements and invention assignment agreements can be breached and we may not have adequate remedies for any such breach. For more information regarding the risks related to our intellectual property, see "Risk Factors - Risks Related to Our Intellectual Property."

The patent positions of biotechnology companies like ours are generally uncertain and involve complex legal, scientific and factual questions. Geopolitical actions in the United States and in foreign countries could increase the uncertainties and costs surrounding the prosecution or maintenance of our patent applications or those of any current or future licensors and the maintenance, enforcement or defense of our issued patents or those of any current or future licensors. Our commercial success will also depend in part on not infringing upon the proprietary rights of third parties. It is uncertain whether the issuance of any third-party patent would require us to alter our development or commercial strategies, or our drugs or processes, obtain licenses or cease certain activities. Our breach of any license agreements or our failure to obtain a license to proprietary rights required to develop or commercialize our future products may have a material adverse impact on us. If third parties prepare and file patent applications in the United States that also claim technology to which we have rights, we may have to participate in interference or derivation proceedings in the United States Patent and Trademark Office (the "USPTO") to determine priority of invention. For more information, see "Risk Factors - Risks Related to Our Intellectual Property."

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Government Regulation

Government authorities in the United States at the federal, state and local level and in other countries regulate, among other things, the research, development, testing, manufacture, quality control, approval, labeling, packaging, storage, record-keeping, promotion, advertising, distribution, post-approval monitoring and reporting, marketing and export and import of drug and biological products. Generally, before a new drug or biologic can be marketed, considerable data demonstrating its quality, safety and efficacy must be obtained, organized into a format specific for each regulatory authority, submitted for review and approved by the regulatory authority.

U.S. Drug Development

In the United States, the FDA regulates drugs under the Federal Food, Drug, and Cosmetic Act ("FDCA"), and its implementing regulations, and biologics under the FDCA, the Public Health Service Act ("PHSA"), and their implementing regulations. Both drugs and biologics also are subject to other federal, state and local statutes and regulations. The process of obtaining regulatory approvals and the subsequent compliance with appropriate federal, state, local and foreign statutes and regulations requires the expenditure of resources. Failure to comply with the applicable U.S. requirements at any time during the product development process, approval process or post-market may subject an applicant to administrative or judicial sanctions. These sanctions could include, among other actions, the FDA’s refusal to approve pending applications, withdrawal of an approval, a clinical hold, untitled or warning letters, product recalls or market withdrawals, product seizures, total or partial suspension of production or distribution, injunctions, fines, refusals of government contracts, restitution, disgorgement and civil or criminal penalties. Any agency or judicial enforcement action could have a material adverse effect on us.

Any future product candidates must be approved by the FDA through either a new drug application ("NDA"), or a biologics license application ("BLA"), process before they may be legally marketed in the United States. The process generally involves the following:

•Completion of extensive nonclinical studies in accordance with applicable regulations, including studies conducted in accordance with good laboratory practice ("GLP"), requirements;

•Submission of an IND to the FDA, which must become effective before human interventional clinical trials may begin;

•Approval by an independent institutional review board ("IRB") at each clinical trial site before each trial may be initiated;

•Performance of adequate and well-controlled human clinical trials in accordance with applicable IND regulations, good clinical practice ("GCP") requirements and other clinical trial-related regulations to establish the safety and efficacy of the investigational product for each proposed indication;

•Submission to the FDA of an NDA or BLA;

•A determination by the FDA within 60 days of its receipt of an NDA or BLA to accept the filing for review;

•Satisfactory completion of a FDA pre-approval inspection of the manufacturing facility or facilities where the drug or biologic will be produced to assess compliance with current good manufacturing practices ("cGMP"), requirements to assure that the facilities, methods and controls are adequate to preserve the drug or biologic’s identity, strength, quality and purity;

•Potential FDA inspection of the preclinical and/or clinical trial sites that generated the data in support of the NDA or BLA;

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•FDA review and approval of the NDA or BLA, including consideration of the views of any FDA advisory committee, prior to any commercial marketing or sale of the drug or biologic in the United States; and

•Compliance with any post-approval requirements, including the potential requirement to implement a Risk Evaluation and Mitigation Strategy ("REMS"), and the potential requirement to conduct post-approval studies.

Preclinical Studies and IND

The preclinical developmental stage generally involves laboratory evaluations of drug chemistry, formulation and stability, as well as studies to evaluate pharmacology, pharmacokinetics and toxicity in animals, which support subsequent clinical testing. The sponsor must submit the results of the preclinical studies, together with chemistry, manufacturing, and control information, analytical data, including pharmacology and toxicology information, any available clinical data or literature, investigator's brochure, and a proposed clinical protocol, among other information, to the FDA as part of the IND. An IND is a request for authorization from the FDA to administer an investigational product to humans, and must become effective before human clinical trials may begin.

Preclinical studies include laboratory evaluation of product chemistry and formulation, as well as in vitro and animal studies to assess the pharmacology, pharmacokinetics, and potential for adverse events and in some cases to establish a rationale for therapeutic use. The conduct of preclinical studies is subject to federal regulations and requirements, including GLP regulations for safety/toxicology studies. An IND sponsor must submit the results of the preclinical tests, together with manufacturing information, analytical data, any available clinical data or literature and plans for clinical studies, among other things, to the FDA as part of an IND. Some long-term preclinical testing, such as animal tests of reproductive adverse events, chronic toxicity and carcinogenicity, may continue after the IND is submitted. An IND automatically becomes effective 30 days after receipt by the FDA, unless before that time, the FDA raises concerns or questions related to one or more proposed clinical trials that precludes study initiation and places the trial on clinical hold. In such a case, the IND sponsor and the FDA must resolve any outstanding concerns before the clinical trial can begin. As a result, submission of an IND may not result in the FDA allowing clinical trials to commence.

Clinical Trials

The clinical stage of development involves the administration of the investigational product to healthy volunteers or patients under the supervision of qualified investigators, generally physicians not employed by or under the trial sponsor’s control, in accordance with GCP requirements, which include the requirement that all research subjects provide their informed consent for their participation in any clinical trial. Interventional clinical trials are conducted under protocols detailing, among other things, the objectives of the clinical trial, dosing procedures, subject selection and exclusion criteria and the parameters to be used to monitor subject safety and assess efficacy. Each protocol, and any subsequent amendments to the protocol, must be submitted to the FDA as part of the IND. Furthermore, each clinical trial must be reviewed and approved by an IRB for each institution at which the clinical trial will be conducted to ensure that the risks to individuals participating in the clinical trials are minimized and are reasonable in relation to anticipated benefits. The IRB also approves the informed consent form that must be provided to each clinical trial subject or his or her legal representative, and must monitor the clinical trial until completed. There also are requirements governing the reporting of ongoing clinical trials and completed clinical trial results to public registries.

A sponsor who wishes to conduct a clinical trial outside of the United States may, but need not, obtain FDA authorization to conduct the clinical trial under an IND. If a foreign clinical trial is not conducted under an IND, the sponsor may submit data from the clinical trial to the FDA in support of an NDA or BLA. The FDA will accept a well-designed and well-conducted foreign clinical trial not conducted under an IND if the trial was conducted in accordance with GCP requirements and the FDA is able to validate the data through an onsite inspection if deemed necessary.

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Clinical trials in the United States generally are conducted in three sequential phases, known as Phase 1, Phase 2 and Phase 3, which may overlap or be combined:

•Phase I clinical trials generally involve a small number of healthy volunteers or disease-affected patients who are initially exposed to a single dose and then multiple doses of the product candidate. The primary purpose of these clinical trials is to assess the metabolism, pharmacologic action, and initial side effect tolerability and safety of the drug.

•Phase II clinical trials involve studies in a limited number of disease-affected patients to evaluate the preliminary efficacy, optimal dosages, and dosing schedule and to identify possible adverse side effects and safety risks.

•Phase III clinical trials generally involve a large number of patients at multiple sites and are designed to provide the data necessary to demonstrate the effectiveness of the product for its intended use, its safety in use and to establish the overall benefit/risk relationship of the product and provide an adequate basis for product approval. These trials may include comparisons with placebo and/or other comparator treatments. The duration of treatment is often extended to mimic the actual use of a product during marketing.

When these phases overlap or are combined, the trials may be referred to as Phase 1/2 or Phase 2/3. Post-approval trials, sometimes referred to as Phase 4 clinical trials, may be conducted after initial marketing approval. These trials are used to gain additional experience from the treatment of patients in the intended therapeutic indication. In certain instances, the FDA may mandate the performance of Phase 4 clinical trials as a condition of approval of an NDA or BLA.

Progress reports detailing the results of the clinical trials, among other information, must be submitted at least annually to the FDA. Expedited written IND safety reports must be submitted to the FDA, IRBs, and the investigators for serious and unexpected suspected adverse events, findings from other studies suggesting a significant risk to humans exposed to the drug, findings from animal or in vitro testing that suggest a significant risk for human subjects and any clinically important increase in the rate or severity of a serious suspected adverse reaction over that listed in the protocol or investigator brochure.

Phase 1, Phase 2 and Phase 3 clinical trials may not be completed successfully within any specified period, if at all. The FDA or the sponsor may suspend or terminate a clinical trial at any time on various grounds, including a finding that the research subjects or patients are being exposed to an unacceptable health risk. Similarly, an IRB can suspend or terminate approval of a clinical trial at its institution if the clinical trial is not being conducted in accordance with the IRB’s requirements or if the drug or biologic has been associated with unexpected serious harm to patients. Additionally, some clinical trials are overseen by an independent group of qualified experts organized by the clinical trial sponsor, known as a data safety monitoring board or committee. This group provides authorization for whether a trial may move forward at designated check points based on access to certain data from the trial. Concurrent with clinical trials, companies usually complete additional animal studies and also must develop additional information about the chemistry and physical characteristics of the drug or biologic as well as finalize a process for manufacturing the product in commercial quantities in accordance with cGMP requirements. The manufacturing process must be capable of consistently producing quality batches of the product and, among other things, companies must develop methods for testing the identity, strength, quality and purity of the final product. Additionally, appropriate packaging must be selected and tested and stability studies must be conducted to demonstrate that our product candidates do not undergo unacceptable deterioration over their shelf life.

We may be required to develop and implement additional clinical trial policies and procedures designed to help protect subjects from public health concerns, such as a global pandemic. For example, the FDA has issued various guidance documents on conducting clinical trials during the COVID-19 pandemic, including certain reporting requirements and additional guidance on good manufacturing practice considerations for responding to global pandemic infection.

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NDA/BLA Review Process

Following completion of the clinical trials, data are analyzed to assess whether the investigational product is safe and effective for the proposed indicated use or uses. The results of preclinical studies and clinical trials are then submitted to the FDA as part of an NDA or BLA, along with the proposed labeling, and information relating to the product's chemistry, manufacturing, and controls, among other information, to ensure consistent product quality, safety, and efficacy. In short, the NDA or BLA is a request for approval to market the drug or biologic for the specified indication(s) and must contain sufficient evidence of efficacy, acceptable safety profile, and appropriate quality attributes. The application may include both negative and ambiguous results of preclinical studies and clinical trials, as well as positive findings. Data may come from company-sponsored clinical trials intended to test the safety and efficacy of a product’s use and/or from a number of alternative sources, including but not limited to studies initiated by investigators or cooperative clinical groups. To support marketing approval, the data submitted must be sufficient in quality and quantity to establish the safety and efficacy of the investigational product to the satisfaction of FDA. FDA approval of an NDA or BLA must be obtained before a drug or biologic may be marketed in the United States.

Under the Prescription Drug User Fee Act ("PDUFA"), as amended, each NDA or BLA must be accompanied by a user fee. FDA adjusts the PDUFA user fees on an annual basis. According to the FDA’s FY 2026 user fee schedule, effective through September 30, 2026, the user fee for an application requiring clinical data, such as an NDA or BLA, is $4,682,003. PDUFA also imposes an annual program fee for each marketed human drug or biologic of $442,213.Fee waivers or reductions are available in certain limited circumstances. Additionally, no user fees are assessed on NDAs or BLAs for products designated as orphan drugs for an orphan indication submission.

The FDA reviews all submitted NDAs and BLAs before it accepts them for filing, and may request additional information rather than accepting the NDA or BLA for filing, such as the issuance of a Refuse to File ("RTF") letter. The FDA must make a decision on accepting an NDA or BLA for filing within 60 days of receipt. Once the submission is accepted for filing, the FDA begins an in-depth review of the NDA or BLA. Under the goals and policies agreed to by the FDA under PDUFA, the FDA has ten months, from the filing date, in which to complete its initial review of a new molecular-entity NDA or original BLA and respond to the applicant, and six months from the filing date of a new molecular-entity NDA or original BLA designated for priority review. The FDA does not always meet its PDUFA goal dates for standard and priority NDAs or BLAs, and the review process may be extended by FDA requests for additional information or clarification.

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DNLI US Equity

DNLI · 10-K · period ended 2025-12-31

ITEM 1. BUSINESS

DNLI US Equity☆

DNLI · 10-K · period ended 2025-12-31

ITEM 1. BUSINESS

DNLI US Equity