Bezuclastinib for Nonadvanced systemic mastocytosis
The FDA is expected to decide on Bezuclastinib for Nonadvanced systemic mastocytosis by December 30, 2026, under a NDA from Cogent Biosciences.
What is being decided
Cogent Biosciences has a NDA under FDA review for Bezuclastinib in Nonadvanced systemic mastocytosis. Selective KIT D816V inhibitor for the most common form of systemic mastocytosis.
Who this decision matters to
Systemic Mastocytosis is a rare hematologic disorder characterized by accumulation and proliferation of abnormal mast cells in bone marrow, lymphoid tissues, and other organs. Most cases involve a KIT D816V mutation. Symptoms result from mast cell mediator release and range from mild to life-threatening, including anaphylaxis, flushing, diarrhea, and bone pain.
Prevalence: Approximately 1 case per 10,000 to 20,000 people; can occur at any age but more common in adults. See our full Systemic Mastocytosis page for current treatments, recruiting trials, and community resources.
What each outcome would mean
An approval starts a second race rather than ending the first one: specialty pharmacy setup, insurance review, and patient assistance typically take weeks even when everything goes right. Our guide to the 90 days after a rare disease approval explains the timeline and the moves families can make on day 1.
A complete response letter would mean the FDA declined to approve in the application's current form. CRLs are often about manufacturing or data presentation rather than efficacy, and resubmission is common. Either way, this page updates with the outcome and what it means.
Where Systemic Mastocytosis treatment stands today
Research in Systemic Mastocytosis continues expanding treatment options for different subtypes and genetic profiles. Kinase inhibitors like midostaurin, already FDA-approved for advanced forms, are part of a growing arsenal of targeted therapies. Newer trials are investigating additional kinase inhibitors and combination approaches designed to both reduce mast cell burden and manage the troublesome mediator symptoms that impact quality of life. Because some cases involve genetic mutations other than KIT, research is increasingly exploring alternative therapeutic targets for broader patient populations. Given the complexity of this disease and the expanding treatment landscape, consulting with a mast cell disease specialist is valuable for understanding which trials might be appropriate for your specific disease subtype and genetic profile. Participating in disease registries helps track long-term outcomes and keeps you informed as therapies evolve.
Meanwhile, 13 Systemic Mastocytosis trials are recruiting
Whatever the FDA decides here, research on Systemic Mastocytosis does not stop. A few currently enrolling studies, US sites first:
Get notified when new systemic-mastocytosis trials open or existing trials change status, add sites, or update eligibility.
Frequently asked questions
When will the FDA decide on Bezuclastinib?
The FDA's target decision date (PDUFA date) for Bezuclastinib in Nonadvanced systemic mastocytosis is December 30, 2026, disclosed by Cogent Biosciences. The agency can act before this date and occasionally runs past it.
What is Bezuclastinib being reviewed for?
Cogent Biosciences submitted a NDA for Bezuclastinib in Nonadvanced systemic mastocytosis. Selective KIT D816V inhibitor for the most common form of systemic mastocytosis.
What happens after the Bezuclastinib decision?
If approved, availability is not immediate: specialty pharmacy setup, insurance review, and patient assistance typically take weeks even when everything goes right. If the FDA issues a complete response letter, the application was not approved in its current form; CRLs are often about manufacturing or data presentation rather than efficacy, and sponsors frequently resubmit. This page updates with the outcome either way.
Where this date comes from
The FDA does not publish PDUFA dates; companies disclose them. This one comes from Cogent press release. Dates can move, and the FDA can act early or late. This page rechecks against our calendar, which is re-verified weekly.