Abbisko Therapeutics Co. Ltd. announced that its CSF-1R inhibitor Pimicotinib(ABSK021)has been granted the breakthrough therapy designation from FDA for the treatment of tenosynovial giant cell tumor (TGCT) patients that are not amenable to surgery. This breakthrough therapy designation approval is based on results from the phase Ib clinical trial of TGCT cohort for Pimicotinib.

Pimicotinib is the new-generation CSF-1R drug candidate recognized by the US FDA as a breakthrough therapy. This is another crucial milestone for Abbisko Therapeutics after Pimicotinib was awarded the ‘Breakthrough Therapy Drug' certification by the Center for Drug Evaluation, NMPA, in July 2022. The dual recognition of breakthrough therapy in China and the United States demonstrates the innovative research and development strength of Abbisko.

Breakthrough Therapy designation is a process designed by the US FDA, China CDE, and other regulatory agencies to expedite the development and review of drugs that are intended to treat a serious condition, and preliminary clinical evidence indicates that the drug may demonstrate substantial improvement over available therapy on a clinically significant endpoint. Pimicotinib is a novel, orally available, highly selective, and highly potent small molecule inhibitor of CSF-1R independently discovered and developed by Abbisko Therapeutics. A number of studies have shown that blocking the CSF-1R signaling pathway could effectively modulate and change macrophage functions, and potentially treat many macrophage-dependent human diseases.

Pimicotinib is currently being investigated as a treatment for tenosynovial giant cell tumor (TGCT) and cGVHD, and under evaluation as treatment for a number of other indications. In July 2022, pimicotinib was granted Breakthrough Therapy Designation from the Center for Drug Evaluation, NMPA for the treatment of TGCT that is not amenable to surgery. Subsequently in October 2022, Abbisko Therapeutics obtained CDE approval to conduct a Phase III clinical trial in TGCT for pimicotinib.

Prior to these, pimicotinib demonstrated significant antitumor efficacy in a phase Ib trial in patients with TGCT, achieving a preliminary ORR of 68.0% and favorable safety profile. Abbisko Therapeutics also completed a Phase Ia dose escalation study for ABSK021 in the U.S. and is conducting an ongoing Phase Ib multi-cohort expansion trial in both the U.S. and China. In addition to TGCT and cGVHD, Abbisko Therapeutics is actively exploring the potential of ABSK021 in treating many other types of solid tumors and has collaborated with Sperogenix (Shanghai) MedTech Co.

Ltd. in exploring its potential for treating amyotrophic lateral sclerosis (ALS) among other central nervous system disorders. As of current, no highly selective CSF-1R inhibitor has been approved in China.