WALTHAM, Mass. and BOULDER, Colo., April 1, 2026
Cogent Biosciences, Inc. has announced the successful submission of a New Drug Application (NDA) to the U.S. FDA for bezuclastinib, a targeted therapy for patients with gastrointestinal stromal tumors (GIST) who have previously been treated with imatinib, marking a significant regulatory milestone supported by compelling Phase 3 PEAK trial results. The submission was made under the FDA’s Real-Time Oncology Review (RTOR) program, highlighting the urgency and potential clinical impact of the therapy, which has already received Breakthrough Therapy Designation. This development positions bezuclastinib as a promising new option in a space where treatment resistance remains a major challenge.
Phase 3 Data Demonstrates Strong Efficacy in Resistant GIST
The NDA is supported by results from the global, randomized Phase 3 PEAK trial, which evaluated bezuclastinib in combination with sunitinib versus standard sunitinib monotherapy in patients with imatinib-resistant GIST. The study demonstrated a 50% reduction in the risk of disease progression or death (HR=0.50), a highly statistically significant improvement that underscores the therapy’s clinical value. Median progression-free survival (mPFS) reached 16.5 months in the combination arm compared to 9.2 months with standard therapy, representing a substantial extension in disease control.
Additionally, the therapy achieved an objective response rate (ORR) of 46%, nearly doubling the 26% observed with sunitinib alone, indicating a robust anti-tumor effect. These findings highlight bezuclastinib’s potential to significantly outperform current second-line treatment standards and improve outcomes in a genetically driven cancer population.
Targeted Mechanism and Favorable Safety Profile
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Bezuclastinib is a selective tyrosine kinase inhibitor designed to target KIT mutations, particularly KIT exon 17 and D816V mutations, which are key drivers in both GIST and systemic mastocytosis. By selectively inhibiting these oncogenic pathways, the therapy offers a precision medicine approach tailored to genetically defined tumors, enhancing therapeutic effectiveness while minimizing off-target effects. Importantly, the combination therapy demonstrated a favorable safety and tolerability profile, with no new or unexpected safety signals observed compared to the known profile of sunitinib.
Patients receiving the combination therapy also showed prolonged treatment duration, with projections exceeding 19 months, suggesting sustained clinical benefit and improved disease management. This balance of efficacy and tolerability is critical in oncology, where long-term treatment adherence plays a vital role in patient outcomes.
Regulatory Momentum and Future Development Strategy
The NDA submission under the RTOR pathway reflects the high clinical importance and strong data package supporting bezuclastinib, potentially enabling accelerated review timelines. Cogent Biosciences is also advancing additional clinical programs, including a planned Phase 2 trial in first-line GIST patients with exon 9 mutations, further expanding the therapy’s potential clinical applications. Additionally, an NDA submission for advanced systemic mastocytosis (AdvSM) is expected in the first half of 2026, demonstrating a broader development strategy targeting KIT-driven diseases.
The company has also established Expanded Access Programs (EAPs) to provide early access for eligible patients, reflecting its commitment to addressing urgent patient needs while regulatory review is ongoing. These initiatives position Cogent as a key innovator in precision oncology therapeutics, with bezuclastinib at the forefront of its pipeline.
With strong Phase 3 efficacy data, a clear regulatory pathway, and a targeted mechanism addressing unmet needs in resistant cancers, bezuclastinib represents a potential breakthrough in GIST treatment, offering new hope for patients who have limited options after standard therapies fail and reinforcing the growing impact of precision medicine in oncology innovation.
Source: Cogent Biosciences, Inc press release
