SM therapy shows promise in phase 2 trial

Cogent Biosciences recently published promising new data from the phase 2 SUMMIT clinical trial investigating bezuclastinib for the treatment of systemic mastocytosis (SM).

Cogent Biosciences recently published new data from the SUMMIT clinical trial investigating the effectiveness of the  experimental drug bezuclastinib for the treatment of systemic mastocytosis (SM).

SM is a disease characterized by increased mast cell activity that can compromise different organs and body structures, including the gastrointestinal tract, respiratory system, skin and bones. 

Bezuclastinib is an experimental drug belonging to the tyrosine kinase inhibitor family. It blocks the activity of the mutated KIT D816 cellular pathway, which is responsible for the excessive mast cell activity observed in SM.

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The phase 2 SUMMIT trial was designed to investigate the effectiveness of bezuclastinib as an SM treatment. The trial assesses symptom improvements from the patient’s perspective using a new tool called the Mastocytosis Symptom Severity Daily Diary (MS2D2).

“I am impressed with the rapid patient response and reductions seen across all domains at 12 weeks, as well as the safety and tolerability,” stated Lindsay Rein, MD, Associate Professor of Medicine in the Division of Hematologic Malignancies and Cellular Therapy at Duke University. “I believe bezuclastinib shows promise in treating nonadvanced systemic mastocytosis where significant unmet needs remain.” 

Preliminary results showed that over half of the patients included in the study reported a substantial improvement in severe SM-associated symptoms. Furthermore, the majority of patients report significant improvement in skin symptoms as well as other symptoms, including dizziness and brain fog. There were no severe adverse effects associated with the administration of 100mg of the drug. 

Definitive results of the study are expected for the last quarter of 2025. The phase 3 PEAK trial, which aims to assess safety and effectiveness in a larger population, has already begun patient recruitment.