30 October 2023, Shanghai – Abbisko Therapeutics Co., Ltd. (“Abbisko Therapeutics” hereafter) announced that two major clinical updates of its CSF-1R inhibitor pimicotinib（ABSK021）will be presented at the 2023 Connective Tissue Oncology Society Annual Meeting, which will be held in Ireland from November 1 to 4, 2023. The two clinical updates include reporting the design of the pivotal global multi-center phase III clinical trial and the further update of the phase Ib clinical trial of pimicotinib.

Abbisko will present the following posters at the CTOS:

Abstract ID: 1572315

Title: MANEUVER STUDY: A PHASE 3, RANDOMIZED, DOUBLE-BLIND, PLACEBO-CONTROLLED, MULTICENTER STUDY OF PIMICOTINIB (ABSK021) TO ASSESS THE EFFICACY AND SAFETY IN PATIENTS WITH TENOSYNOVIAL GIANT CELL TUMOR

Category: Trials in Progress

Abstract ID: 1571943

Title: UPDATED EFFICACY AND SAFETY PROFILE OF PIMICOTINIB (ABSK021) INTENOSYNOVIAL GIANT CELL TUMOR (TGCT): 1-YEAR FOLLOW-UP FROM PHASE 1B

Category: Medical & Pediatric Oncology and Trials

About Pimicotinib

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 breakthrough therapy designation and Priority Medicine (PRIME) designation by China NMPA, U.S. FDA, and Europe EMA for the treatment of TGCT that is not amenable to surgery. According to epidemiological data, its incidence rate rose from 28/million people in 1998 to 49/million people in 2012, and the number of new cases in China and the U.S. is about 60,000 and 14,000 people each year. Thus, many existing patients are in desperate need of drug treatment. TCGT mainly results in swelling, pain, stiffness, and decreased activity of the affected joints which seriously affect the patient’s quality of life. There is currently no approved drug available in China, and only one systemic therapy agent has been approved in the U.S.. However, it is only available through the Risk Evaluation and Mitigation Strategy (REMS) Program due to potential liver injuries it may cause. There are unmet medical needs of TGCT patients in China, the U.S., and Europe.

Abbisko has completed a Phase Ia dose escalation study for pimicotinibin the U.S., followed by a Phase Ib expansion trial ongoing and a global phase III MRCT trial initiated in China, the U.S. and Europe. In addition to TGCT, Abbisko is actively exploring the potential of pimicotinib in treating other indications including many types of solid tumors in clinic, and has obtained approval from NMPA to conduct a Phase II clinical study in chronic graft-versus-host disease and advanced pancreatic cancer, and also exploring its potential for treating ALS and other CNS diseases. As of the date of this press release, no highly selective CSF-1R inhibitor has been approved in China.

About TGCT

TGCT is a locally aggressive neoplasm which usually affects synovial joints, mucous sacs, and tendon membranes, resulting in swelling, pain, stiffness, and decreased activity of the affected joints which seriously affect the patient’s quality of life [1]. According to the 2013 World Health Organization classification, TGCTs were classified as localized TGCT and diffuse TGCT. Diffuse TGCT encompasses formerly known nodular tenosynovitis and pigmented villonodular synovitis (PVNS). Overexpression of CSF-1 occurs in most TGCTs. Surgical resection is the standard treatment for TGCT. However, not all patients are suitable for surgical treatment. It is difficult to remove tumors of diffuse TGCT patients by surgery, which may possibly lead to severe joint damage, total synovectomy, joint replacement, or even amputation, and the risk of surgical complications can be high. It has been reported that more than 50% of patients with diffuse TGCT will undergo recurrence after surgical resection [2]. For TGCT patients not amenable to surgery, there is currently no approved drug available in China.

[1] Stacchiotti S, Dürr HR, Schaefer IM, et al. Best clinical management of tenosynovial giant cell tumour (TGCT): A consensus paper from the community of experts. Cancer Treat Rev. 2023;112:102491.

[2] Verspoor FG, van der Geest IC, Vegt E, Veth RP, van der Graaf WT, Schreuder HW. Pigmented villonodular synovitis: current concepts about diagnosis and management. FutureOncol. 2013;9(10):1515-1531.