Syros Pharmaceuticals Inc. (SYRS) stock took a significant hit on Tuesday, plummeting over 60% after the company announced the discontinuation of enrollment in its SELECT-AML-1 Phase 2 trial. The trial, evaluating a combination therapy for acute myeloid leukemia (AML), yielded disappointing results that ultimately led to the decision to halt further enrollment.
The SELECT-AML-1 trial aimed to compare the effectiveness of a triplet regimen, combining tamibarotene with venetoclax (Venclexta, sold by AbbVie Inc. ABBV and Roche Holdings AG RHHBY) and azacitidine (Vidaza, marketed by Bristol Myers Squibb & Co. BMY), against a standard doublet regimen of venetoclax and azacitidine in newly diagnosed, unfit AML patients with RARA gene overexpression. However, an interim analysis of data from 51 patients revealed similar complete response (CR)/complete response with incomplete hematologic recovery (CRi) rates in both the triplet and doublet arms. This lack of significant improvement in the triplet regimen’s effectiveness led to the conclusion that the trial was unlikely to demonstrate superiority in the final analysis.
Despite the setback in the AML trial, Syros remains committed to developing tamibarotene as a treatment option. The company is continuing its evaluation of tamibarotene in combination with azacitidine in the SELECT-MDS-1 Phase 3 trial, focusing on newly diagnosed higher-risk myelodysplastic syndrome (MDS) patients with RARA gene overexpression. This trial, which passed a prespecified futility analysis earlier this year, is expected to deliver pivotal CR data by the end of 2024.
The news of the SELECT-AML-1 trial discontinuation has significantly impacted SYRS stock, reflecting investor sentiment regarding the potential of tamibarotene as a treatment option for AML. However, Syros remains hopeful that its ongoing efforts in MDS research will yield positive results, potentially mitigating the negative impact of the AML trial outcome.
While the company is disappointed by the unexpected outcome of the AML trial, Syros emphasizes that there were no new safety concerns associated with the combination therapy. Patients currently enrolled in SELECT-AML-1 have the option to continue their participation in the trial at the discretion of the study investigators. Syros plans to present data from the SELECT-AML-1 trial at the Society of Hematologic Oncology Annual Meeting in September.
