Lilly to Acquire Adverum Biotechnologies (Form SC14D9C)

Lilly to Acquire Adverum Biotechnologies

Adverum's lead program, Ixo-vec, is a Phase 3 gene therapy designed to treat vision loss associated with wet age-related macular degeneration with a single intravitreal dose

Acquisition aligns Lilly's genetic medicine capabilities with opportunity to expand gene therapy's potential to alleviate the burden of age-related diseases

INDIANAPOLIS and REDWOOD CITY, Calif., October 24, 2025 - Eli Lilly and Company (NYSE: LLY) and Adverum Biotechnologies, Inc. (Nasdaq: ADVM), a clinical-stage company pioneering the use of intravitreal gene therapy with the aim of preserving sight for life in highly prevalent ocular diseases, today announced a definitive agreement for Lilly to acquire Adverum Biotechnologies, Inc. ("Adverum"), including its lead product candidate, Ixo-vec.

Adverum is developing a pipeline of intravitreal single-administration gene therapies with the aspiration of developing functional cures to restore vision and prevent blindness. Its lead product candidate, Ixo-vec, is an intravitreal gene therapy being developed for the treatment of wet age-related macular degeneration (wAMD). This serious, chronic and progressive retinal disease affects millions of people worldwide. Ixo-vec is designed as a single one-time treatment to deliver continuous and stable intraocular aflibercept levels, thereby reducing the significant patient burden associated with current chronic anti-VEGF therapies, while also potentially leading to improved vision outcomes.

Ixo-vec is being evaluated in the ARTEMIS Phase 3 clinical trial, which has completed screening. The program has been granted Fast Track and Regenerative Medicine Advanced Therapy (RMAT) designations by the U.S. Food and Drug Administration, as well as PRIME designation by

the European Medicines Agency and the Innovation Passport from the United Kingdom's Medicines and Healthcare Products Regulatory Agency for the treatment of wAMD.

"Ixo-vec has the potential to transform wAMD treatment from a paradigm of chronic care with repeated intravitreal injections to a convenient one-time therapy," said Andrew Adams, Lilly group vice president, Molecule Discovery. "We are eager to welcome Adverum colleagues to Lilly and to help accelerate this innovative medicine to patients."

"We are excited about the potential to join Lilly, with a proven track record in the discovery, development, and commercialization of innovative medicines for chronic and age-related conditions," said Laurent Fischer, M.D., president and chief executive officer of Adverum Biotechnologies. "We share Lilly's commitment to healthy aging and genetic medicines innovation. Their scientific depth and global reach offer the opportunity to accelerate our vision to deliver a transformative One and Done^™ therapy that can potentially restore and preserve vision for millions of patients living with wAMD. My deepest appreciation goes out to the entire Adverum team for their expertise, creativity and commitment. We are also grateful to the investigators, patients and caregivers who have contributed to the success of Ixo-vec thus far."

Under the terms of the merger agreement, Lilly will commence a tender offer to acquire all of the outstanding shares of Adverum common stock for a per share price of (1) $3.56 per share in cash payable at closing plus (2) one non-transferrable contingent value right (CVR) that entitles the holder to receive up to an additional $8.91 per CVR in cash upon the achievement of two milestones described below, for total potential per share consideration of up to $12.47.

The CVR provides payments if and when the following milestones are achieved:

The transaction is subject to closing conditions that appear in the merger agreement and tender offer documents that will be filed with the SEC, including the tender of a majority of the outstanding shares of Adverum's common stock. These conditions do not include a financing condition. The transaction is expected to close in the fourth quarter of 2025, subject to satisfaction of the closing conditions. If the tender offer successfully closes, then Lilly would acquire any shares of Adverum that are not tendered in the tender offer through a second-step merger for the same consideration as is paid in the tender offer.

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In conjunction with the transaction, Adverum has entered into a Promissory Note (the "Promissory Note") with Lilly. The Promissory Note is secured by all of Adverum's assets, including all of its intellectual property rights, and enables Adverum to receive a loan of up to $65 million from Lilly, drawable by Adverum in four installments, subject to specified conditions, to support ongoing Ixo-vec clinical trials and registrational development activities prior to the anticipated closing of the transaction. Funding obligations cease and the Promissory Note immediately becomes due if the transaction is terminated, including as a result of the minimum tender condition not being satisfied. Absent funds provided by Lilly under the Promissory Note, Adverum's remaining cash and cash equivalents were expected to finance only its October 2025 operations and wind down activities.

The transaction was unanimously approved by Adverum's board of directors following a comprehensive evaluation of strategic alternatives. This evaluation process included numerous discussions with potential partners and buyers. In addition, the board of directors evaluated a range of potential sources of additional capital and financing options. It was determined that the merger agreement with Lilly, inclusive of the potential upside for Adverum's stockholders of the CVR as Lilly advances development of Ixo-vec, is in the best interests of Adverum and its stockholders.

For Lilly, Ropes & Gray LLP is acting as legal counsel. For Adverum, Aquilo Partners, L.P. is acting as exclusive financial advisor and Cooley LLP is acting as legal counsel.

About Lilly

Lilly is a medicine company turning science into healing to make life better for people around the world. We've been pioneering life-changing discoveries for nearly 150 years, and today our medicines help tens of millions of people across the globe. Harnessing the power of biotechnology, chemistry and genetic medicine, our scientists are urgently advancing new discoveries to solve some of the world's most significant health challenges: redefining diabetes care; treating obesity and curtailing its most devastating long-term effects; advancing the fight against Alzheimer's disease; providing solutions to some of the most debilitating immune system disorders; and transforming the most difficult-to-treat cancers into manageable diseases. With each step toward a healthier world, we're motivated by one thing: making life better for millions more people. That includes delivering innovative clinical trials that reflect the diversity of our world and working to ensure our medicines are accessible and affordable. F-LLY

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About Adverum Biotechnologies

Adverum Biotechnologies (NASDAQ: ADVM) is a clinical-stage company that aims to establish gene therapy as a new standard of care for highly prevalent ocular diseases with the aspiration of developing functional cures to restore vision and prevent blindness. Leveraging the capabilities of its proprietary intravitreal platform, Adverum is developing durable, single-administration therapies, designed to be delivered in physicians' offices, to eliminate the need for frequent ocular injections to treat these diseases. Adverum is evaluating its novel gene therapy candidate, ixoberogene soroparvovec (Ixo-vec, formerly referred to as ADVM-022), as a one-time, IVT injection for patients with neovascular or wet age-related macular degeneration. Additionally, by overcoming the challenges associated with current treatment paradigms for debilitating ocular diseases, Adverum aspires to transform the standard of care, preserve vision, and create a profound societal impact around the globe.

About Ixo-vec in Wet AMD

Adverum is developing ixoberogene soroparvovec (Ixo-vec, formerly referred to as ADVM-022), its clinical-stage gene therapy product candidate, for the treatment of wet AMD. Ixo-vec utilizes a proprietary vector capsid, AAV.7m8, carrying an aflibercept coding sequence under the control of a proprietary expression cassette. Unlike other ophthalmic gene therapies that require surgery to administer the gene therapy under the retina (sub-retinal approach), Ixo-vec is designed to be administered as a one-time IVT injection in the physician's office, deliver long-term efficacy, reduce the burden of frequent anti-VEGF, optimize patient compliance, and improve vision outcomes for patients with wet AMD. In recognition of the need for new treatment options for wet AMD, FDA granted Fast Track and Regenerative Medicine Advanced Therapy (RMAT) designations for Ixo-vec for the treatment of wet AMD. Ixo-vec has also received PRIME designation from the EMA and the Innovation Passport from the United Kingdom's Medicines and Healthcare Products Regulatory Agency for the treatment of wet AMD.