Syros Pharmaceuticals shares (NASDAQ:SYRS) lost nearly a third of their value Monday after investors learned that, by the end of October, just one out of 48 evaluable patients enrolled in an ongoing study of the company's lead gene control therapy, SY-1425 (tamibarotene), had achieved a complete response. The ongoing trial is evaluating SY-1425 for the treatment of genomically defined subsets of patients with acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS). No patients with lower-risk MDS had achieved transfusion independence, another endpoint of the study, by the cut-off for reporting.