Study of Posoleucel (ALVR105,Viralym-M) for Multi-Virus Prevention in Patients Post-Allogeneic Hematopoietic Cell Transplant

Key Inclusion Criteria: * Any age at the day of screening visit. * No known or suspected clinically significant disease from AdV, BKV, CMV, EBV, HHV-6, and/or JCV * Within 25 days of receiving a first allogeneic HCT and have demonstrated clinical engraftment at time of dosing * Meet one or more of the following criteria at the time of randomization: * Related (sibling) donor with at least one mismatch at one of these HLA-gene loci: HLA-A, -B or -DR * Haploidentical donor * Matched or Mismatched unrelated donor * Use of umbilical cord blood as stem cell source * Ex vivo graft manipulation resulting in T cell depletion * Received anti-thymocyte globulin or alemtuzumab (Campath-1H) Key Exclusion Criteria: * History of AdV, BKV, CMV, EBV, HHV-6, and/or JCV end-organ disease within 6 months prior to randomization * Evidence of active Grade \>2 acute GVHD * Presence of non-minor uncontrolled or progressive bacterial, viral or fungal infections * Known history or current (suspected) diagnosis of Grade ≥3 CRS requiring treatment associated with the administration of peptides, proteins, and/or antibodies * Ongoing therapy with high-dose systemic corticosteroids (ie, prednisone equivalent dose \>1.0 mg/kg/day) within 24 hours prior to dosing * Relapse of primary malignancy other than minimal residual disease Note: Other protocol defined Inclusion/Exclusion criteria may apply.