Vanda Pharmaceuticals Secures Global License to Develop and Market Imsidolimab

Vanda Pharmaceuticals Inc. and AnaptysBio, Inc. have entered into a worldwide, exclusive licensing agreement for the development and commercialization of imsidolimab. This IL-36R antagonist monoclonal antibody has concluded its registration-enabling Phase 3 trials, GEMINI-1 and GEMINI-2, which evaluated its safety and efficacy for treating Generalized Pustular Psoriasis (GPP), a rare and severe skin disease.

GPP is characterized by widespread pustules and systemic inflammation, often attributed to mutations in the IL36RN gene. This gene is responsible for a regulatory protein that manages the IL-36 cytokine family. When the IL-36 signaling is disrupted, it can lead to severe chronic inflammation, significantly contributing to morbidity and mortality associated with complications like sepsis and multi-organ failure. Imsidolimab functions by inhibiting IL-36R, thereby compensating for the lack of natural IL-36 regulation in GPP patients.

Vanda plans to undertake technology transfer activities in 2025, with immediate steps to prepare applications for U.S. and EU regulatory approvals and commercialization strategies. Mihael H. Polymeropoulos, Vanda’s President and CEO, expressed enthusiasm about adding imsidolimab to Vanda’s portfolio, highlighting the drug’s potential to address other inflammatory conditions where IL-36 balance is compromised. This addition aligns with Vanda’s expertise in treating rare diseases, complemented by their anti-inflammatory products like Ponvory® for multiple sclerosis, psoriasis, and ulcerative colitis.

Estimates of GPP prevalence range widely, with figures suggesting between 1.76 to 124 patients per million globally. The majority of cases result from genetic mutations in IL36RN, leading to uncontrolled IL-36 activity due to loss-of-function mutations. Johann Gudjonsson, a molecular skin immunology professor at the University of Michigan, noted the promising Phase 3 results, where patients showed rapid disease clearance and maintained skin clarity for at least 24 weeks post-treatment with imsidolimab. The data revealed no significant safety concerns, marking a hopeful advancement for GPP therapy as regulatory submissions are anticipated this year.

Daniel Faga, CEO of Anaptys, emphasized Vanda’s fit as a partner due to their adeptness in regulatory and commercial operations, particularly in the U.S. and Europe, and their commitment to expanding their therapeutic labels. Following a productive pre-BLA meeting with the FDA in 2024, Anaptys looks forward to Vanda’s regulatory submissions in 2025, aiming to provide a differentiated therapeutic option for GPP, a potentially life-threatening skin condition.

According to the agreement terms, Vanda will pay Anaptys $10 million upfront and an additional $5 million for existing drug supplies. Anaptys may earn up to $35 million based on future regulatory and sales milestones, along with a 10% royalty on net sales. Vanda gains exclusive global rights to develop, produce, and market imsidolimab.

The GEMINI-1 trial involved 45 patients who received either 750mg or 300mg of intravenous imsidolimab or a placebo. The results showed that a significant percentage of patients treated with imsidolimab achieved near-clear skin compared to those receiving a placebo. In the subsequent GEMINI-2 trial, patients who responded in GEMINI-1 were re-randomized to receive monthly subcutaneous imsidolimab or placebo. Those continuing treatment maintained their GPPPGA score without flares, reinforcing imsidolimab’s favorable safety and tolerability.

Imsidolimab is a humanized antibody targeting IL-36R, developed to address GPP. If untreated, GPP can be life-threatening, as patients suffer from severe pustule outbreaks and systemic symptoms like fever and fatigue. Vanda Pharmaceuticals focuses on innovative therapies for unmet medical needs, while Anaptys is dedicated to developing immunology therapeutics for autoimmune and inflammatory diseases, with a pipeline that includes treatments for rheumatoid arthritis and ulcerative colitis.