Biotechnology In the second setback in the space of a little over a month, Magenta Therapeutics saw its shares crash 23.3% to $0.38 pre-market today, after the US biotech revealed that the latest participant dosed at the Cohort 3 level (0.08mg/kg) in the ongoing MGTA-117 Phase I/II dose-escalation clinical trial in relapsed/refractory acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) experienced a Grade 5 serious adverse event (SAE) (respiratory failure and cardiac arrest resulting in death) deemed to be possibly related to MGTA-117. 26 January 2023