SHANGHAI, Jan. 8, 2024 /PRNewswire/ -- On January 9, 2024 (Beijing Time), Abbisko Therapeutics (HKEX code: 02256) announced that its investigational innovative CSF-1R inhibitor pimicotinib（ABSK021） has been granted orphan drug designation（ODD） by the European Medicines Agency (EMA) for the treatment of inoperable tenosynovial giant cell tumor (TGCT).

Following the successful ODD granted by the EMA, the product will benefit from incentives, including protocol assistance, fee reductions, procedural advantages for market authorization, and market exclusivity and so on. In addition to the above-mentioned benefits within the European Union, member states may also offer specific stimuli for orphan drugs.

Previously, in June 2023, pimicotinib was granted the Priority Medicines（PRIME） designation by the EMA, which aims to expedite the review process for promising medicines in areas of unmet medical needs.

In early December 2023, Abbisko entered into an agreement with Merck that granted it an exclusive license to commercialize pimicotinib for all indications in the Chinese mainland, Hong Kong, Macau, and Taiwan. Merck also obtained an exclusive option for global commercial rights of pimicotinib, subject to the terms and conditions as agreed between the parties. Pursuant to the terms of the license agreement, Abbisko will receive a one-time, non-refundable down payment of US$ 70 million. In the event that Merck exercises the global commercialization option, Merck will pay Abbisko an additional option exercising fee. The aggregate amounts of upfront payment, option exercising payment, and payment for development and commercialization milestones will total US$ 605.5 million. Abbisko will also receive double-digit percentage (%) royalties on annual net sales.

Pimicotinib is a novel, orally available, highly selective, and potent small molecule CSF-1R inhibitor, independently developed by Abbisko Therapeutics. It has been granted the Break Through Designation（BTD） and PRIME designation by China NMPA, U.S. FDA, and EMA for the treatment of TGCT patients who are not amenable to surgery. The study is the first global Phase III clinical trial of TGCT conducted simultaneously in China, the U.S., Canada and Europe.

Upon 1-year follow-up in a Phase 1b trial for TGCT, pimicotinib demonstrated an ORR of 87.5% (28/32, including 3 CR) in the 50 mg QD cohort，which was presented at the 2023 CTOS. Pimicotinib has completed a Phase I dose-escalation trial in the U.S. In December this year, it was granted Fast Track Designation (FTD) by the U.S. FDA for the treatment of unresectable TGCT .