Pre-Exposure Prophylaxis with Tixagevimab-Cilgavimab May Not Reduce Covid-19 Severity Among Lung Transplant Recipients That Develop Breakthrough Infection

ABSTRACT

Tixagevimab-cilgavimab (Tix-Cil) is a long-acting monoclonal antibody combination granted Emergency Use Authorization approval for COVID-19 pre-exposure prophylaxis (PrEP) in immunocompromised patients, due to their suboptimal response to vaccination. We sought to determine whether Tix-Cil reduces COVID-19 severity among lung transplant recipients (LTRs) who develop breakthrough infection. After IRB approval, we conducted a retrospective chart review of LTRs who developed COVID-19 during the Omicron surge (December 2021 to August 2022). We performed comparative analyses using Fisher's exact test and logistic regression to control for vaccination and other monoclonal antibodies. A total of 89 LTRs with COVID-19 were included. The median time from LT to COVID-19 diagnosis was 38.3 months (IQR 20.3, 66.9). The median age was 67.4 years (59.5-72.4), 49 (55.1%) were male, 87 (97.8%) had undergone bilateral LT, 48 (53.9%) had diabetes, 25 (28.0%) were obese (body mass index ≥30 kg/m2), and 67 (75.3%) had chronic kidney disease (eGFR <60 mL/min/1.73m2). The most common immunosuppressive regimen included mycophenolate mofetil, tacrolimus, and prednisone (64;71.9%), and the median percent predicted FEV1 was 87% (IQR 64.5, 99.5). The overwhelming majority of patients received at least 2 doses of an mRNA vaccine (84 (94.3%)) and 60 (67.4%) were treated with monoclonal antibodies, 51 (57.3%) with antivirals, and 82 (92.1%) with increased corticosteroids upon COVID-19 diagnosis. Despite Tix-Cil prophylaxis, 24 LTRs contracted COVID-19 during the Omicron surge. The median time from Tix-Cil to COVID-19 diagnosis was 90.5 days (60.3, 119.0). PrEP with Tix-Cil did not reduce hospitalization, ICU admission, need for mechanical ventilation or death among LTRs. Pre-exposure prophylaxis with Tix-Cil may not reduce COVID-19 severity among LTRs that develop breakthrough infection. [ABSTRACT FROM AUTHOR] Copyright of Journal of Heart & Lung Transplantation is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)