T Cell Therapy Opposing Novel COVID-19 Infection in Immunocompromised Patients

The primary purpose of this phase I study is to assess the safety of administering donor-derived CSTs in immunocompromised participants for prevention of SARS-CoV-2 infection. Related and unrelated donors of participants who are at risk of SARS-CoV-2 infection will be enrolled for screening and production of CSTs from peripheral blood. Following product manufacturing, participants who have undergone HSCT will receive donor-derived CSTs for prevention of SARS-CoV-2 infection. It is a dose escalation study with separate study arms for adult (Arm A) and pediatric (Arms B and C) recipients of HSCT who are at risk of SARS-CoV-2 infection. Participants who have undergone HSCT and test negative for SARS-CoV-2 infection will be enrolled and receive one dose of CST product derived from their HSCT donor for prophylaxis. Participants aged ≥18 years and \<80 years will be enrolled on Arm A, participants who are ≥12 years of age and \<18 years of age will be enrolled on Arm B, and participants who are ≥2 years of age and \<12 years of age will be enrolled on Arm C. Investigators will test three doses: 1x107 /m2, 2x107 /m2, and 4x107 /m2. At least 3 adult participants (Arm A) will be enrolled at each dose level before pediatric participants (Arm B) are enrolled. At each dose level, treatment of the first two adult participants enrolled at that dose level will be staggered at least 28 days apart and each will be followed for the 45-day safety monitoring period to assess safety and efficacy of CST product. Once the third adult participant on any given dose level has completed their 45-day safety monitoring period and the safety and efficacy data is reviewed and approved by the FDA, then adult participants can be escalated to the next dose level and pediatric participants can start enrollment at the dose level completed by the adult participants. If participants show evidence of safety and at least 2 of 3 have evidence of antiviral immune reconstitution against SARS-CoV-2, investigators will enroll pediatric participants at that dose level following FDA approval. Additionally, infusion of pediatric participants enrolled at each dose level will be staggered at least 28 days apart, and all enrolled participants will be followed for 45 days for safety monitoring after CST infusion. After receiving the CST infusion, participants will be closely monitored to evaluate their health status and the effects of treatment. Follow-up visits will occur frequently and will continue for up to 1 year after the CST infusion. During these visits, study doctors will perform clinical assessments, including medical history and physical examinations. Blood tests will be conducted, such as complete blood count (CBC) and comprehensive metabolic panel (CMP), and research blood samples will also be collected for analysis. These assessments will help monitor safety, toxicity, and treatment effects.