Step Pharma Doses First Participant In Phase 1b Clinical Trial Of Dencatistat For Essential Thrombocythaemia

Step Pharma, a global leader in CTPS1 inhibition for targeted cancer therapies, has announced that the first participant has been dosed in a Phase 1b clinical trial of its lead asset, dencatistat, for the treatment of essential thrombocythaemia (ET). ET is a rare blood disorder in which the bone marrow produces an excessive number of platelets, increasing the risk of blood clots that can cause serious complications such as stroke or heart attack. While current treatments aim to reduce platelet counts to lower these risks, they can cause side effects or may not be suitable for all patients, underscoring the need for safer and more targeted approaches.

Dencatistat has already shown encouraging results in clinical studies involving patients with lymphoma. Continuous administration of the therapy produced a dose-dependent and reversible reduction in platelet counts. Although this effect has been managed with intermittent dosing in lymphoma or solid tumour patients, the strong safety and tolerability profile of dencatistat makes it a promising candidate for treating ET, where lowering platelet counts is central to disease management.

Andrew Parker, Chief Executive Officer of Step Pharma, mentioned, “Initiating the clinical evaluation of dencatistat in essential thrombocythaemia represents a significant milestone in our ‘pipeline in a product’ strategy. We believe we can harness selective CTPS1 inhibition to provide a safer, targeted approach to the treatment of ET. This expansion into a new indication, alongside our ongoing trials in lymphoma and solid tumours, further demonstrates the   potential versatility of dencatistat as a targeted therapy. We look forward to collaborating with clinical investigators and those living with ET to advance this important programme.”

The newly launched Phase 1b open-label trial will assess the safety, tolerability, and preliminary activity of dencatistat in approximately 20 adult patients with high-risk ET. Eligible participants include those who are resistant to, or unable to tolerate, hydroxycarbamide (hydroxyurea), the most commonly used therapy. The study is being conducted at 12 clinical sites across France and the United Kingdom.