 CAMBRIDGE, Mass.--BUSINESS WIRE--Syros Pharmaceuticals NASDAQ:SYRS, a leader in the development of medicines that control the expression of genes, today announced that the first patient has been dosed in the dose confirmation study of SY-2101, a novel oral form of arsenic trioxide ATO. The trial will evaluate the pharmacokinetics PK, safety, and tolerability of SY-2101 to confirm the optimal dose to advance into a planned Phase 3 clinical trial in newly diagnosed acute promyelocytic leu 