RAPT Therapeutics and Jemincare Announce License Deal for New Anti-IgE Antibody

RAPT Therapeutics, Inc., a clinical-stage biopharmaceutical company based in South San Francisco, has entered into a significant license agreement with Shanghai Jemincare Pharmaceutical Co., Ltd, a subsidiary of the Jiangxi Jemincare Group. This collaboration focuses on the monoclonal antibody JYB1904, also known as RPT904, which is geared towards treating various allergic disorders. RAPT has secured the rights to develop and market RPT904 globally, except in China, Hong Kong, Macau, and Taiwan—territories retained by Jemincare.

Under the terms of this agreement, Jemincare receives an upfront payment of $35 million and stands to gain up to $672.5 million in milestone payments, along with royalties on sales outside its retained territories. The goal of RPT904 is to offer a potentially superior therapeutic option compared to omalizumab, a well-known anti-IgE monoclonal antibody used for a range of allergic conditions. The initial focus for RAPT904 is its development in the treatment of food allergies.

Currently, Jemincare is actively conducting Phase 2 clinical trials for JYB1904 in China, focusing on asthma and chronic spontaneous urticaria (CSU). Brian Wong, President and CEO of RAPT, expressed enthusiasm about the partnership with Jemincare, emphasizing RPT904's potential to emerge as a leading treatment option for food allergies. He noted the rapid adoption of omalizumab in food allergy treatment since its approval, highlighting the significant need in this market. RAPT plans to launch a Phase 2b clinical trial for RPT904 targeting food allergies in the latter half of 2025.

Jemincare has successfully completed a Phase 1 trial in China, involving 56 healthy volunteers, which compared multiple dosages of JYB1904 to omalizumab and a placebo. Results indicated that JYB1904 had favorable safety and tolerability, with dose-dependent pharmacokinetics and a median half-life over twice that of omalizumab. The trial also revealed that JYB1904 was more effective in reducing free IgE levels and accumulating total IgE than omalizumab.

As Jemincare continues its Phase 2 trials in asthma and CSU, the data from these studies will be instrumental in determining appropriate dosing for potential Phase 3 trials. The outcomes of Jemincare's Phase 2 asthma trial are expected by the second half of 2025, while the CSU trial results should be available in the first half of 2026.

This partnership between RAPT and Jemincare represents a strategic alliance aimed at advancing the development and commercial potential of JYB1904/RPT904. RAPT's commitment to exploring new treatment avenues for food allergies and other allergic disorders, combined with Jemincare's ongoing clinical efforts, positions RPT904 as a promising candidate in addressing unmet patient needs in allergic diseases. This collaboration leverages the strengths of both companies, potentially accelerating the path to bringing innovative therapies to market and improving patient outcomes in allergic disease management.