SARS-CoV-2 Messenger RNA Vaccine Antibody Response and Reactogenicity in Heart and Lung Transplant Recipients: SARS-CoV-2 vaccine response in heart and lung recipients

Hallett, Andrew M.; Greenberg, Ross S.; Boyarsky, Brian J.; Shah, Pali D.; Ou, Michael T.; Teles, Aura T.; Krach, Michelle R.; López, Julia I.; Werbel, William A.; Avery, Robin K.; Bae, Sunjae; Tobian, Aaron A.; Massie, Allan B.; Higgins, Robert S.D.; Garonzik-Wang, Jacqueline M.; Segev, Dorry L.; Bush, Errol L.

Background: While several studies have observed that solid organ transplant recipients experience diminished antibody responses to SARS-CoV-2 mRNA vaccination, data specific to heart and lung transplant (HT/LT) recipients remains sparse. Methods: US adult HT and LT recipients completed their vaccine series between January 7 and April 10, 2021. Reactogencity and SARS-CoV-2 anti-spike antibody were assessed after a priming dose (D1) and booster dose (D2). Modified Poisson regression with robust variance estimator was used to evaluate associations between participant characteristics and antibody development. Results: Of 134 heart recipients, there were 38% non-responders (D1-/D2-), 48% booster responders (D1-/D2+), and 14% priming dose responders (D1+/D2+). Of 103 lung recipients, 64% were non-responders, 27% were booster responders, and 9% were priming dose responders. Lung recipients were less likely to develop antibodies (p<0.001). Priming dose antibody response was associated with younger recipient age (p=0.04), transplant-to-vaccination time ≥ 6 years (p<0.01), and lack of anti-metabolite maintenance immunosuppression (p<0.001). Pain at injection site was the most commonly reported reaction (85% after D1, 76% after D2). Serious reactions were rare, the most common being fatigue (2% after D1 and 3% after D2). No serious adverse events were reported. Conclusions: HT and LT recipients experienced diminished antibody response following vaccination; reactogenicity was comparable to that of the general population. LT recipients may exhibit a more impaired antibody response than HT recipients. While current recommendations are to vaccinate eligible candidates and recipients, further studies characterizing the cell-mediated immune response and clinical efficacy of these vaccines in this population are needed.