Syros Pharmaceuticals has reported encouraging initial findings from its SELECT-AML-1 Phase II clinical trial of tamibarotene plus venetoclax and azacitidine to treat acute myeloid leukaemia (AML) patients.

The trial is designed to evaluate the efficacy and safety of tamibarotene plus venetoclax and azacitidine versus venetoclax and azacytidine in nearly 80 newly diagnosed unfit AML patients positive for RARA overexpression.

Complete response rate (CR)/complete response with incomplete haematologic recovery (CRi) is the trial’s primary endpoint.

Trial data showed that the tamibarotene combination treatment offered a 100% CR/CRi rate in evaluable patients versus 70% in the control arm.

Furthermore,78% and 22% of subjects who received the combination regimen achieved a CR and Cri, respectively versus 30% and 40% for control.

The combination treatment resulted in a median time to CR/CRi response of 21 days versus 25 days for those treated with the control.

The tamibarotene combination regimen was found to be well tolerated in the trial with the overall safety profile showing no additive toxicities or new safety signals.

Syros Pharmaceuticals chief medical officer David Roth said: “These data highlight the potential of tamibarotene to be a cornerstone therapy for newly diagnosed, unfit AML patients with RARA overexpression, further demonstrating its differentiated product profile and validating our biologically targeted approach.

“These results, the first from a randomised, controlled study, demonstrate the potential impact of adding tamibarotene to the standard-of-care, venetoclax and azacitidine and, importantly, are consistent with prior experience.

“Across multiple clinical trials, we have observed tamibarotene’s ability to rapidly deliver clinically relevant activity, with a well-tolerated safety profile, including in a combination setting.”

The company is currently enrolling more patients in the trial and expects to report updated study findings data next year.

Apart from this trial, Syros is assessing tamibarotene plus azacitidine in the Phase III SELECT-MDS-1 trial in newly diagnosed higher-risk myelodysplastic syndrome patients with RARA gene overexpression.

The subject enrolment in SELECT-MDS-1 is expected to conclude in the first quarter of next year with CR data expected by the fourth quarter.