A readout from the company’s SUMMIT trial put its small molecule bezuclastinib on a collision course with rival Blueprint’s Ayvakit, which Leerink analysts said does not sufficiently treat all patients.
Cogent Biosciences’ tyrosine kinase inhibitor bezuclastinib eased symptoms in patients with systemic mastocytosis, according to a Phase II readout on Monday. On the heels of those data, the company is planning a New Drug Application, Cogent’s first, to the FDA by the end of the year.
Cogent’s stock was up 26% Monday afternoon following the news.
Analysts at Leerink compared bezuclastinib to Blueprint Medicines’ Ayvakit. “We continue to believe that [bezuclastinib] has a meaningful [systemic mastrocytosis] opportunity by first addressing the ~20-30% of higher symptom burden patients not adequately treated by Ayvakit,” they wrote in a note to investors after the data readout.
In Cogent’s SUMMIT trial, which compared bezuclastinib to placebo, the treatment arm hit its primary endpoint, delivering a statistically significant difference in total symptom scores of 24.3 points versus 15.4 points in the placebo arm, using a measurement scale Cogent created for the study.
The trial also hit secondary endpoints, including 87.4% of treated patients seeing a 50% drop in serum tryptase, a biomarker for mastocytosis, where no patients in the placebo arm achieved a similar drop. The company will present more detailed results at a medical meeting later this year.
Ayvakit was approved in May 2023 for a particular subgroup of mastrocytosis patients. Leerink’s comparison between Cogent’s and Blueprint’s drugs is noteworthy given that the two companies have butted heads of late, to say the least. At the recent Jefferies Global Healthcare Conference, Cogent CEO Andy Robbins said Ayvakit “was so toxic that it was killing patients,” according to STAT.
The safety profile for bezuclastinib was “better than expected,” according to the Leerink analysts. SUMMIT reported side effects like change in hair color (69.5% of treatment patients), altered taste (23.7%) and elevated liver enzymes (22.0%). The Crinkles noted that this differentiated the drug from Ayvakit, which has side effects that include edema, dizziness, bleeding events like hematoma and hemorrhage and cognitive adverse effects. Leerink attributed the relatively clean safety profile to bezuclastinib’s “higher selectivity and lack of brain penetrance.”
“In total, we model ~$2.5bn for peak [bezuclastinib’s] revenues,” the Leerink analysts concluded.
