C4 Therapeutics Halts BRAF Blocker, Focuses on Multiple Myeloma Drug

C4 Therapeutics, a biotechnology firm based in Massachusetts, has shifted its strategic focus to enhance its efforts on cemsidomide, an oral drug candidate currently under trial for treating multiple myeloma and non-Hodgkin lymphoma. This strategic pivot involves discontinuing the investment in CFT1946, an investigational BRAF inhibitor, to prioritize capital allocation effectively. The company is also seeking development partners to further the BRAF program, particularly due to the significant unmet needs and strong rationale for using degraders to treat BRAF V600 mutant solid tumors.

Previously, CFT1946 showed promising results in a Phase I trial last September, where it demonstrated a favorable pharmacokinetic and safety profile. These initial outcomes suggested the potential for CFT1946 to significantly impact the treatment paradigm for certain solid tumors, noted CEO Andrew Hirsch. BRAF, a signaling protein, often carries a V600 mutation in various cancer types. C4 intends to present data from a Phase I dose-escalation study of CFT1946 involving patients with melanoma or colorectal cancer at an upcoming scientific conference.

The decision to halt progress on CFT1946 was announced as part of the company’s first-quarter earnings report. In the first quarter of 2025, C4 Therapeutics reported a net loss of $26.3 million, slightly better than the $28.4 million loss recorded in the same period the previous year. The company ended the first quarter with $234.7 million in cash, cash equivalents, and marketable securities, providing them with enough financial resources to operate until 2027.

With the focus now firmly on cemsidomide, C4 Therapeutics aims to advance its study of this drug candidate. Cemsidomide is an experimental oral degrader targeting the IKZF1/3 transcription factors, and it is being tested in multiple myeloma trials. Phase I data have indicated a significant response to cemsidomide, with an overall response rate of 50% as of the April 30 data cutoff. The company plans to conclude the Phase I dose-escalation trial and present the findings by the third quarter.

In addition to its applications in multiple myeloma, C4 is investigating cemsidomide for non-Hodgkin’s lymphoma, conducting Phase I dose-escalation studies. The company aims for a readout in this area by the end of the year. C4 is also awaiting regulatory feedback regarding the registrational development of cemsidomide, which it anticipates receiving by mid-year.

The reallocation of resources underscores C4 Therapeutics’ commitment to maximizing the potential of cemsidomide while exploring collaborative opportunities to advance other programs. This strategic move reflects the company’s dedication to addressing challenging medical needs and leveraging innovative approaches in cancer treatment.