Ligand Acquires Royalty and Milestone Interest in Santen’s Ryjunea® from Sydnexis for $23 Million (Form 8-K)

Ligand Acquires Royalty and Milestone Interest in Santen's Ryjunea® from Sydnexis for $23 Million

Ryjunea is the first and only pharmacologic treatment approved by the European Commission and UK MHRA to slow myopia progression in pediatric patients

Ligand will receive a tiered low-double-digit to high-teens royalty on Ryjunea net sales in Europe, the Middle East, and Africa

JUPITER, Fla., September 22, 2026 - Ligand Pharmaceuticals Incorporated (Nasdaq: LGND) today announced it has acquired an ascending tiered royalty interest in Santen Pharmaceutical Co., Ltd.'s ("Santen") Ryjunea® from Sydnexis, Inc. ("Sydnexis") for a $23 million upfront payment.

Ryjunea is a once-nightly, low-dose atropine eye drop designed to slow progression of myopia (commonly known as nearsightedness) in pediatric patients. Treatment may be indicated in children aged 3-14 years with a progression rate of 0.5 D or more per year and a severity of -0.5 D to -6.0 D. The product uses a standardized 0.01% formulation of atropine with deuterated water designed to improve efficacy, comfort, and stability in the pediatric population. Santen licensed rights to Ryjunea in Europe, the Middle East, and Africa ("EMEA") from Sydnexis in 2021. Ryjunea was approved by the European Commission in June 2025 and the UK Medicines and Healthcare products Regulatory Agency ("MHRA") in October 2025.

"Ryjunea represents the type of differentiated asset we look to add to our expanding royalty portfolio. As the first and only approved pharmacological treatment in the European Union and the United Kingdom for slowing pediatric myopia, Ryjunea addresses a significant market need by providing a stable, clinically validated, and GMP manufactured option to manage this chronic condition. Santen has built a strong ophthalmology presence across Europe and has identified myopia as a key strategic growth area, giving us confidence in the product's long-term commercial potential," said Todd Davis, CEO of Ligand.

Under the terms of the agreement, Ligand will pay $23 million upfront to acquire a 100% interest in certain payments and related rights under Sydnexis's existing license agreement with Santen. The acquired payment rights include a tiered low-double-digit to high-teens royalty on Ryjunea net sales in EMEA, as well as certain milestone payments. Sydnexis retains commercial rights to Ryjunea in the U.S. and all other non-Santen licensed territories.

Myopia is a condition in which the focal point for distant objects is in front of the retina, instead of directly on it, and results in vision loss. It has been reported that, in addition to affecting patient quality of life, the progression to "high myopia" increases the risk of severe ocular complications that can lead to permanent visual impairment or blindness. In Europe, approximately 1 in 3 children and adolescents are projected to be affected by myopia by 2050,i and Santen estimates 14 million patients were affected in 2025.ii

McDermott Will & Schulte LLP and Cooley LLP served as legal advisors to Ligand.

About Ligand

Ligand is a leading royalty aggregator, partnering with biopharmaceutical companies to finance and advance late-stage clinical development programs. Ligand owns and manages one of the largest and most diversified portfolios of biopharmaceutical royalties in the industry, with economic interests in more than 200 development and commercial-stage assets. Ligand funds high-value programs in exchange for long-term economic interests, aligning capital with clinical and commercial success. Ligand's royalty portfolio is designed to deliver consistent and predictable revenue streams across a broad range of therapeutic assets. Ligand also licenses its proprietary technologies, Captisol® and NITRICIL™, to support drug development and formulation across its global partner network. For more information, visit www.ligand.com or follow Ligand on X and LinkedIn.