Effectiveness of Messenger Ribonucleic Acid Vaccine in Lung Transplant Recipients

PURPOSE: Immunization is heralded as a key tool to combat the COVID-19 pandemic. One key technology, messenger RNA (mRNA) vaccines have demonstrated an efficacy greater than 94%(1,2). While mRNA vaccines create strong protection in the majority of patients, the antibody response in solid organ recipients has been reported to be less reliable(3). Herein, we report the incidence and mortality of COVID-19 in lung transplant recipients after receiving a messenger RNA vaccine (BNT162b2 [Pfizer-BioNTech] or mRNA1273 [Moderna]). METHODS: From February 1, 2021 to September 1, 2021, SARS-CoV-2 positivity, admissions to the hospital, and mortality among lung transplant recipients was recorded at our institution. This timeframe was selected as the mRNA vaccine became available to recipients of lung transplantation in February of 2021. To obtain the immunization status of lung transplant recipients eligible for vaccination with one of the two mRNA vaccines, a query of the electronic medical record was performed during the previously mentioned dates. RESULTS: Among 317 patients, 276 had received at least two doses of mRNA vaccine (87%). Twenty-six tested positive (8.2%). Of the 26 individuals who developed COVID-19, 20 (76.9%) required admission to the hospital with eight deaths (30.8%). Four deaths occurred among the 13 individuals who contracted SARS-CoV-2 despite having received a minimum of two doses of mRNA vaccine representing a 30.7% mortality. The average duration between immunization and a positive PCR result was 86 days (SD 56 days) for individuals who had received at least two doses of a vaccine. CONCLUSION: Recent studies have shown that a third dose of the mRNA vaccine BNT162b2 (Pfizer-BioNTech) can augment the antibody response in solid organ transplantation recipients(4). The immunogenicity of the mRNA vaccine in this population still remains less vigorous compared to the immunocompetent. The reduced efficacy of mRNA vaccines combined with the elevated rate of admission and mortality described above, demonstrate that vaccination alone cannot annul the impact of COVID-19 in these patients. When mask wearing, social distancing, and hand-washing fail, therapies such as casirivimab and imdevimab (REGN-COV2), neutralizing monoclonal antibodies against SARS-CoV-2 could be considered in early disease to suppress viral load(5) and protect this vulnerable population despite immunization status.