NEW YORK – Syros Pharmaceuticals on Monday said it has finished enrolling 190 patients in the SELECT-MDS-1 Phase III trial, in which it is testing the oral selective retinoic acid receptor alpha (RARα) agonist tamibarotene in higher-risk RARA-overexpressing myelodysplastic syndrome.
With enrollment of this initial patient cohort completed, Syros will be on track to report pivotal data from the trial in late 2024. If successful, the Cambridge, Massachusetts-based firm will file a new drug application with the US Food and Drug Administration seeking tamibarotene's approval in higher-risk RARA-overexpressing myelodysplastic syndrome patients.
In the trial, Syros researchers are comparing patients' complete response rates on tamibarotene plus azacitidine against azacitidine alone in newly diagnosed patients and will report on this primary endpoint in Q4. The company is planning to file for accelerated or full approval based on the strength of those results combined with supporting data on tamibarotene's durability of response.
If the firm receives accelerated approval, the SELECT-MDS-1 trial is designed to also supply confirmatory results that support conversion to full approval, according to Syros. For example, researchers are tracking overall survival in the overall 550-patient population as a secondary endpoint in the trial.
"This marks an important step in advancing tamibarotene through late-stage clinical development and brings us closer to delivering our RARα agonist as a frontline treatment option for the approximately 50 percent of HR-MDS patients with RARA overexpression," Syros Chief Medical Officer David Roth said in a statement.
Syros is also conducting the SELECT-AML-1 Phase II clinical trial, in which it is studying tamibarotene with venetoclax and azacitidine as a treatment for patients with newly diagnosed acute myeloid leukemia with RARA overexpression.
In October, Syros underwent a corporate restructuring related to its RARA-targeted assets and laid off 35 percent of its workforce. At the time, it paused development of its acute promyelocytic leukemia agent SY-2101.