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magenta THERAPEUTICS Magenta Therapeutics Reports First Quarter Financial Results and Recent Program Highlights Exhibit 99.1 - Two Phase 2 clinical trials underway to evaluate MGTA - 145 plus plerixafor ; initial mobilization , collection , engraftment and disease outcome data in Multiple Myeloma patients to be first presented at the American Society of Clinical Oncology ( ASCO ) Annual Meeting , to be held virtually June 4-8 , 2021 , and at the European Hematology Association ( EHA ) Congress , to be held virtually June 9-17 , 2021 - - Company on track to file Investigational New Drug ( IND ) for MGTA - 117 in mid - 2021 ; plans to initiate a Phase 1/2 clinical trial evaluating MGTA - 117 in patients with Acute Myeloid Leukemia ( AML ) and Myelodysplastic Syndromes ( MDS ) - ― Ended the first quarter of 2021 with approximately $ 132.3 million in cash , cash equivalents and marketable securities and maintains guidance that its cash reserves are expected to fund its operating plan into the first quarter of 2023 - Cambridge , MA - May 6 , 2021 - Magenta Therapeutics ( Nasdaq : MGTA ) , a clinical - stage biotechnology company developing novel medicines to bring the curative power of stem cell transplants to more patients , today reported financial results for the first quarter ended March 31 , 2021 and recent program highlights . " Magenta continues to make progress across our program portfolio , building momentum towards several key anticipated clinical and data milestones throughout 2021 , including the initial Phase 2 trial results evaluating MGTA - 145 plus plerixafor in Multiple Myeloma patients in an autologous transplant setting and filing an IND for first - in - human Phase 1/2 clinical trial of MGTA - 117 , our first product candidate from our targeted conditioning platform , ” said Jason Gardner , D.Phil . , President and Chief Executive Officer , Magenta Therapeutics . “ We are optimistic about our programs ' ability to transform clinical practice of stem cell transplants and gene therapies with new first - line medicines , which we believe could increase access to curative transplants across multiple disease areas . '