29 May 2025, Shanghai – Abbisko Therapeutics Co., Ltd. (“Abbisko Therapeutics”, Stock Code: 02256.HK) today announced receipt of the global commercialization option exercise fee of US$85 million from Merck under the licensing agreement for pimicotinib (ABSK021). This option exercise fee will be recognized as revenue in 2025.

In December 2023, Abbisko Therapeutics entered into an exclusive commercial licensing agreement with Merck regarding pimicotinib, a CSF-1R inhibitor. Under the terms of the agreement, Merck obtained an exclusive license to commercialize pimicotinib for all indications in the Chinese mainland, Hong Kong, Macau and Taiwan, with an option for global commercial rights. In March 2025, Merck exercised its option to obtain the exclusive license to commercialize pimicotinib worldwide. Abbisko is eligible to receive up to US$605.5 million in milestone payments, including upfront, development, and commercial milestones, as well as double-digit percentage royalties on annual net sales of pimicotinib worldwide.

Pimicotinib is a novel, orally administered, highly selective, and potent small molecule CSF-1R inhibitor, independently developed by Abbisko Therapeutics. Abbisko reported positive topline results from the Global Phase III MANEUVER Study in tenosynovial giant cell tumor (“TGCT”) in November 2024, in which pimicotinib met the primary endpoint with an objective response rate (“ORR”) at Week 25 of 54.0% versus 3.2% for placebo (p<0.0001). Treatment with oral, once-daily pimicotinib was well-tolerated, with very low rates of discontinuation due to treatment-related adverse events, and no evidence of cholestatic hepatotoxicity. 

Pimicotinib was recently granted Priority Review by the Center for Drug Evaluation (CDE) of the China National Medical Products Administration (NMPA) for the treatment of patients with tenosynovial giant cell tumor (TGCT), who require systemic therapy. Pimicotinib also has been granted Breakthrough Therapy Designation (BTD) by the China National Medical Products Administration (NMPA) and U.S. Food and Drug Administration (FDA), as well as and Priority Medicine (PRIME) Designation from the European Medicines Agency (EMA) for the treatment of patients with TGCT not amenable to surgery.