COVID Protection After Transplant (CPAT) Multicenter Adaptive Trial

Solid organ transplant recipients experience high mortality from COVID-19 due to a combination of immunosuppression and comorbidities. Although SARS-CoV-2 vaccination has been highly effective in the general population, recent studies show that solid organ transplant recipients are less likely to develop protective antibody responses. In addition, long term studies of safety, including immunologic sequela such as rejection, and de novo donor-specific antibody formation are lacking. We propose a Multicenter Randomized Adaptive Design Trial to investigate strategies for CPAT (COVID Protection After Transplant). This trial will build on results from a CPAT Pilot Trial in 200 kidney transplant reipients which will investigate the safety and immunogenicity of 3rd dose of a SARS-CoV-2 mRNA vaccines in recipients who fail to develop high level antibodies after a standard 2 dose series. That trial will identify key correlates of risk and efficacy. This trial will incorporate that data to investigate additional protective strategies including the use of different vaccine platforms and changes in immunosuppression in 800 solid organ transplant recipients with suboptimal anti-spike antibody responses across 15 US transplant centers. This trial will personalize randomization to candidate arms with the highest probability of success using a Bayesian framework. In conjuction, we will perform novel, comprehensive virologic and immunologic mechanistic studies to better understand vaccine-associated immunity over time. Our multidisciplinary team includes experts in Transplant Surgery, Infectious Diseases, Epidemiology, Biostatistics, Pathology, Virology, and Immunology. Our team has experience successfully enrolling and conducting multicenter transplantation trials (U01AI134591, U01AI138897) and will leverage existing infrastructure for operations, data management, analysis, and safety reporting. In summary, this Multicenter Adaptive Design CPAT Trial will determine the immunogenicity and safety of novel SARS-CoV-2 vaccination strategies in 800 transplant recipients across the United States. Important mechanistic studies will further fundamental understanding of development of protective immune responses in this vulnerable population.