Step Pharma Announces First Patient Dosed with STP938, the World’s Most Advanced CTPS1 Inhibitor, in a Phase 1/2 Trial for T cell and B cell lymphomas

St. Genis-Pouilly, France, 24 October 2022

Step Pharma, the world leader in CTPS1 inhibition for the targeted treatment of cancer, announces today that the first patient has been successfully dosed with STP938, in a Phase 1/2 trial in adult subjects with relapsed/refractory B cell and T cell lymphomas.

The dose-escalation part of the open label, non-randomised Phase 1/2 trial comprises multiple cohorts dosed with STP938, administered as an oral monotherapy, ascending in a stepwise manner. The primary objective in Phase I is to assess the safety and tolerability of STP938.

Brian Schwartz, Chief Medical Officer of Step Pharma, commented:

“We are developing STP938, a highly selective, first-in-class treatment based on ground-breaking genetics. The dosing of the first patient into our Phase 1/2 trial is an important step to identify an optimal dose to take forward into further clinical development for relapsed/ refractory T cell and B cell lymphomas.”

STP938 is a first-in-class oral cancer therapeutic that specifically inhibits nucleotide synthesis and the enzyme cytidine triphosphate synthase 1 (CTPS1) in particular, originally identified as an essential gene for lymphocyte proliferation. By targeting CTPS1, Step Pharma has unlocked the ability to selectively target the de novo pyrimidine synthesis pathway in cancer cells. This ground-breaking approach should enable the highly selective treatment of both blood cancers and solid tumours.

Further details of the study can be found on clinicaltrials.gov under the identifier NCT05463263.