(Updates)
** Shares of drug developer Magenta Therapeutics Inc
MGTA.O fall 48.2% to $0.43, hit record low
** Company stops dosing patients at cohort 4 dosing level in
drug MGTA-117's early-to-mid-stage trial after dose-limiting
toxicities (DLTs) were observed in the second and third dosed
participants
** Toxicity in patients involved a respiratory serious
adverse event, according to company
** The drug is being studied to treat acute myeloid leukemia
(AML) and myelodysplastic syndrome (MDS)
** Both AML and MDS are cancers associated with the blood
and bone marrow
** Company says it reported the clinical data of first
observed DLT to the U.S. FDA; adds information for DLT event in
the second participant is forthcoming
** Magenta now plans to continue enrollment and dose
additional participants at the cohort 3 dosing level
** Including session's fall, stock down 90.3% YTD
(Reporting by Pratik Jain in Bengaluru)
((Pratik.Jain@thomsonreuters.com))