C4 Therapeutics has made the decision to discontinue the development of one of its cancer drugs following an ineffective phase 1/2 trial. The small-molecule biotech company has halted the advancement of CFT8634, an oral BRD9 degrader, for the treatment of synovial sarcoma, a rare form of cancer that typically impacts large joints, as well as SMARCB-1 null tumors, as of a November 1 announcement.
While the drug was well-tolerated by patients, the high levels of BRD9 degradation did not produce the desired therapeutic effects in heavily pre-treated patients receiving CFT8634 as a monotherapy. Consequently, C4 Therapeutics has ceased further enrollment in the trial and expects to completely terminate the study by the end of the first quarter of 2024.
The Massachusetts-based biotech firm has chosen to shift its focus to two other ongoing phase 1/2 trials. The primary candidate, CFT7455, is an IKZF1/3 degrader being investigated in combination with the corticosteroid dexamethasone for patients with relapsed or refractory multiple myeloma (R/R MM) and as a standalone therapy for patients with advanced non-Hodgkin’s lymphoma. In 2022, the company reported early signs of efficacy in five multiple myeloma patients from the CFT7455 trial. In October, it announced the completion of phase 1 dose escalation for CFT7455 in R/R MM, involving 22 patients across five dosing groups.
C4T’s second focus is on CFT1946, a BRAF V600 degrader intended for the treatment of solid tumors, including non-small cell lung cancer (NSCLC), colorectal cancer, and melanoma. The asset is presently being assessed in a phase 1/2 trial involving dose escalation for the treatment of solid tumors characterized by BRAF V600 mutations.
The company’s pipeline also includes CFT8919, a preclinical oral degrader designed to target EGFR L858R mutations found in NSCLC patients. This candidate is the subject of an exclusive licensing agreement with Betta Pharmaceuticals, a biotech company based in China. Betta Pharmaceuticals paid $10 million in cash for the rights to develop and commercialize CFT8919 in the Greater China region. Chinese regulators have accepted Betta’s request to launch clinical trials for review.
According to the terms of the agreement, C4T is expected to receive $35 million, comprising an initial $10 million payment and a one-time $25 million equity investment. However, Betta has not yet disbursed the $25 million equity purchase, citing “business circumstances,” as per the November 1 announcement.
As of September 30, C4 Therapeutics had $246.4 million in cash, cash equivalents, and marketable securities, which is expected to sustain the company through the latter half of 2025.