COGT Bezuclastinib GIST PDUFA Nov 30: First Active-Drug Win

The FDA accepted Cogent Biosciences’ (COGT) New Drug Application for bezuclastinib (CGT9486) in combination with sunitinib for patients with gastrointestinal stromal tumors (GIST) who have received prior treatment with imatinib. The agency granted Priority Review with a PDUFA date of November 30, 2026. No advisory committee meeting is planned.

Cogent closed at $40.44 with a market cap of $6.91 billion. The stock has two PDUFA catalysts within 30 days: the GIST NDA on November 30 and a separate NDA for bezuclastinib in non-advanced systemic mastocytosis on December 30.

The PEAK trial data

The NDA is based on the Phase 3 PEAK trial, the first treatment ever to demonstrate a statistically significant advantage against an active comparator in GIST. Median progression-free survival was 16.5 months for bezuclastinib plus sunitinib versus 9.2 months for sunitinib alone (HR=0.50, 95% CI 0.39-0.65, p<0.0001). The objective response rate was 46% versus 26%. The combination was well tolerated, with no unique risks beyond the known safety profile of sunitinib.

The FDA granted Breakthrough Therapy Designation and Real-Time Oncology Review for the GIST indication, both of which streamline the review process. The full PEAK data were presented at ASCO on May 30, 2026.

Why GIST has been stuck for 20 years

GIST is a rare sarcoma of the digestive tract driven by mutations in the KIT or PDGFRA genes. Imatinib (Gleevec) has been the first-line standard since 2002, and sunitinib (Sutent) has been the second-line standard since 2006. No new second-line therapy has been approved in the two decades since. The treatment field has been stagnant because GIST tumors develop secondary KIT mutations that resist both drugs, and no therapy has successfully addressed that resistance mechanism.

Bezuclastinib is a selective KIT inhibitor designed to target both primary and secondary KIT mutations. In the PEAK trial, the combination of bezuclastinib plus sunitinib showed PFS benefit regardless of primary or secondary KIT mutation genotype, which is the mechanistic rationale for why the combination outperformed sunitinib alone.

The double-catalyst setup

Cogent has two PDUFA dates in a 30-day window, a rare setup that means the market must price in two separate approval decisions. The systemic mastocytosis NDA (December 30) is based on the SUMMIT trial, which showed an 8.91-point placebo-adjusted improvement in Total Symptom Score at 24 weeks (p=0.0002) and an 87.4% tryptase response versus 0% placebo. We covered that indication in our rare disease PDUFA catalysts analysis.

For investors, the question is whether the $6.91 billion valuation is pricing in one approval or two. If both are approved, Cogent would have a franchise spanning oncology (GIST) and rare disease (systemic mastocytosis) with the same molecule.

What to watch

The main risk is that the PEAK trial was open-label, which can introduce bias in PFS assessment. The FDA did not request an advisory committee, which signals confidence in the data, but the agency could still raise concerns about the open-label design or the choice of sunitinib monotherapy as the comparator. The secondary KIT mutation profile and whether the FDA specifies a companion diagnostic for mutation testing will also matter for the label. Cogent also initiated a new trial of bezuclastinib combination in first-line GIST patients, which extends the franchise potential but is years from readout.