Vanda Pharmaceuticals Inc. (Vanda) (Nasdaq: VNDA) and AnaptysBio, Inc. (Anaptys) (Nasdaq: ANAB) announced an exclusive, global license agreement for the development and commercialization of imsidolimab (IL-36R antagonist mAb), which has successfully completed two registration-enabling global Phase 3 trials, GEMINI-1 and GEMINI-2, evaluating the safety and efficacy of imsidolimab in patients with Generalized Pustular Psoriasis (GPP).

GPP is a rare skin disorder often caused by mutations in the IL36RN gene that codes for a regulatory protein that balances the activity of the proinflammatory IL-36 family of cytokines. Dysregulation of this balance in IL-36 signaling leads to severe chronic skin inflammation with pustules and systemic symptoms which carry significant morbidity and mortality often associated with sepsis and multi-organ failure.

Imsidolimab inhibits the function of the IL-36R, compensating for the deficiency of the endogenous IL-36 regulator in patients with GPP. Imsidolimab has successfully concluded its development program in GPP, including the GEMINI-1 and GEMINI-2 global Phase 3 studies.

In 2025, Vanda intends to initiate and complete the technology transfer activities and will immediately begin preparing the BLA and MAA applications for the US and EU and making preparations for commercialization.

"We are excited to add imsidolimab to Vanda's product portfolio for rare orphan disorders, as well as explore the potential of this IL-36 signal regulator in the treatment of additional inflammatory conditions where the IL-36 homeostatic balance is dysregulated," said Mihael H. Polymeropoulos, M.D., Vanda's President, CEO and Chairman of the Board. "Imsidolimab has great synergy with our commercial portfolio, leveraging both our rare disease expertise in the US and EU as well as the anti-inflammatory portfolio that includes Ponvory^® for multiple sclerosis, psoriasis and ulcerative colitis."

GPP prevalence estimates in the general population vary considerably, between 1.76 and 124 patients per million persons worldwide. The majority of GPP cases are caused by genetic variants in IL36RN. Loss-of-function mutations in IL36RN are mostly missense mutations in a recessive pattern and result in unrestricted IL-36 activity.^5,6

"GPP is a severely debilitating, life-threatening skin disease in need of novel therapeutic approaches," said Johann Gudjonsson, M.D., Ph.D., Arthur C. Curtis Professor of Molecular Skin Immunology and Scholar of the Taubman Medical Research Institute, University of Michigan. "The positive Phase 3 data, demonstrating GPP patients achieved rapid disease clearance through Week 4 after a single dose of infused imsidolimab, and maintained clear to almost clear skin for at least 24 weeks, with no clinically meaningful safety signals, represents a promising new option for patients living with this disease. I'm excited imsidolimab is progressing toward a regulatory filing this year."

"Vanda is an ideal partner for imsidolimab due to their strong regulatory and commercial capabilities in the US and Europe, evidenced by successful recent launches in specialty and rare diseases, and their commitment to invest in label expansion across their therapeutic portfolio, including their growing presence in inflammatory disease," said Daniel Faga, president and chief executive officer of Anaptys. "Following our productive pre-BLA meeting with FDA in 2024, we look forward to Vanda's BLA and MAA submissions later in 2025, with the hope that this potentially differentiated therapeutic option will be made available for patients living with GPP, a burdensome, and sometimes life-threatening skin disease."

Under the terms of the agreement, Vanda will make to Anaptys an upfront payment of $10 million and a $5 million payment for existing drug supply. Anaptys is also eligible to receive up to $35 million for future regulatory approval and sales milestones in addition to a 10% royalty on net sales. Vanda will receive an exclusive global license to develop, manufacture and commercialize imsidolimab.

Guggenheim Securities acted as financial advisor and Fenwick & West LLP served as legal counsel to Anaptys on this transaction. Cantor Fitzgerald & Co. acted as financial advisor and Orrick, Herrington & Sutcliffe LLP served as legal counsel to Vanda.