FDA Acceptance of BIIB142 IND Bolsters C4 Therapeutics' Platform Validation

Event Overview: FDA Accepts BIIB142 IND for Autoimmune Diseases

Biogen recently announced that the U.S. FDA has accepted its investigational new drug (IND) application for BIIB142, an IRAK4 degrader designed for the treatment of autoimmune diseases. This regulatory milestone stems from a collaboration with C4 Therapeutics (CCCC), a clinical-stage biopharmaceutical company specializing in targeted protein degradation.

Detail of Regulatory Milestone and Collaboration

The IND acceptance for BIIB142 signifies a crucial step forward for the therapeutic candidate, allowing it to proceed into clinical trials. The drug, which leverages C4 Therapeutics' expertise in targeted protein degradation, is intended to address autoimmune conditions. Under the terms of their collaboration, C4 Therapeutics is entitled to receive a US$2 million milestone payment upon Biogen dosing patients in the BIIB142 clinical trial. Biogen assumes full responsibility for all future clinical development and commercialization of the compound.

Market Reaction and Analytical Insights

This development has served to re-energize short-term investor sentiment for C4 Therapeutics, reinforcing the narrative of its platform validation and the efficacy of its collaborative model. The news prompted a notable market reaction, with C4 Therapeutics stock surging by 13% following an upgrade from Stephens analyst Sudan Loganathan, who moved the stock from Equal Weight to Overweight with a $6.00 price target. Barclays also initiated coverage with an "Overweight" rating and an $8.00 price target. The average target price from six analysts currently stands at $15.00, implying a significant potential upside from its current trading levels. This positive response underscores investor confidence in the company's scientific capabilities and its ability to advance clinical-stage candidates through partnerships.

Broader Context and Financial Landscape

While the BIIB142 IND acceptance is a significant win, C4 Therapeutics operates within a challenging financial landscape. The company remains unprofitable, recording a net loss of $26.0 million in Q2 2025, an increase from $17.7 million in Q2 2024. Revenue for Q2 2025 also saw a decline to $6.5 million from $12.0 million in Q2 2024, partly due to a prior $8.0 million milestone payment from Biogen in Q2 2024. Research and Development (R&D) expenses increased to $26.2 million from $23.8 million in the same period. Despite these sustained losses, C4 Therapeutics maintains a solid cash position, with $223.0 million in cash, cash equivalents, and marketable securities as of June 30, 2025. This financial stability is bolstered by strategic partnership payments, including an upfront $10 million and up to $600 million in potential milestones from a December 2023 collaboration with Merck, along with $4 million from Roche and $1 million from Merck KGaA in preclinical milestones. This cash runway is expected to extend to mid-2027, providing critical time for pipeline progression.

Beyond BIIB142, C4 Therapeutics is also advancing its lead oncology candidate, cemsidomide (CFT7455), for multiple myeloma. Promising Phase 1 clinical data demonstrated a 40% overall response rate (ORR) at the 75 µg dose and a 50% ORR at the 100 µg dose in multiple myeloma patients, indicating its potential as a best-in-class IKZF1/3 degrader. The company plans to present full Phase 1 multiple myeloma data at the International Myeloma Society (IMS) Annual Meeting on September 20, 2025, which is highlighted as a key upcoming catalyst for further program validation.

Looking Ahead: Balancing Progress and Persistent Risks

The FDA's IND acceptance for BIIB142 underscores the potential of C4 Therapeutics' targeted protein degradation platform and its collaborative strategy. This development, coupled with the promising cemsidomide data, is expected to maintain positive investor attention. However, investors are advised to consider the company's persistent financial challenges, including sustained losses and potential for dilution, as fundamental risks have not been entirely mitigated by this single regulatory win. Future catalysts, such as the full cemsidomide Phase 1 data readout and the planned initiation of its registrational development in early 2026, will be critical in shaping the company's trajectory and its ability to translate scientific validation into sustained commercial success.