Key Points Question What are the humoral immune response rates and risk factors associated with diminished response after COVID-19 vaccination in recipients of solid organ transplant? Findings In this systematic review and meta-analysis of 29 studies and 11 713 recipients of solid organ transplant, seroconversion rates increased with progressively increased numbers of mRNA COVID-19 vaccine doses. Older age, recent transplantation, deceased donor status, active use of antimetabolites, and recent exposure to antithymocyte globulin or rituximab were risk factors associated with diminished humoral immune response after receiving 2 doses of mRNA vaccines. Meaning These findings suggest that more efforts are needed to modulate the risk factors associated with reduced humoral responses among recipients of solid organ transplant.

The novel coronavirus disease 2019 (COVID‐19) is a highly infectious and rapidly spreading disease. There are limited published data on the epidemiology and outcomes of COVID‐19 infection among organ transplant recipients. After initial flulike symptoms, progression to an inflammatory phase may occur, characterized by cytokine release rapidly leading to respiratory and multiorgan failure. We report the clinical course and management of a liver transplant recipient on hemodialysis, who presented with COVID‐19 pneumonia, and despite completing a 5‐day course of hydroxychloroquine, later developed marked inflammatory manifestations with rapid improvement after administration of off‐label, single‐dose tocilizumab. We also highlight the role of lung ultrasonography in early diagnosis of the inflammatory phase of COVID‐19. Future investigation of the effects of immunomodulators among transplant recipients with COVID‐19 infection will be important.

ImportancePregnant people are at increased risk of poor outcomes due to infection with SARS-CoV-2, and there are limited therapeutic options available.ObjectiveTo evaluate the clinical outcomes associated with nirmatrelvir and ritonavir used to treat SARS-CoV-2 infection in pregnant patients.Design, Setting, and ParticipantsThis case series included pregnant patients who were diagnosed with SARS-CoV-2 infection, received nirmatrelvir and ritonavir, and delivered their offspring within the Johns Hopkins Health System between December 22, 2021, and August 20, 2022.ExposuresTreatment with nirmatrelvir and ritonavir for SARS-CoV-2 infection during pregnancy.Main Outcomes and MeasuresClinical characteristics and outcomes were ascertained through manual record review.ResultsForty-seven pregnant patients (median [range] age, 34 [22-43] years) were included in the study, and the median (range) gestational age of their offspring was 28.4 (4.3-39.6) weeks. Medication was initiated at a median (range) of 1 (0-5) day after symptom onset, and only 2 patients [4.3%] did not complete the course of therapy because of adverse effects. Thirty patients (63.8%) treated with nirmatrelvir and ritonavir had a comorbidity in addition to pregnancy that could be a risk factor for developing severe COVID-19. Twenty-five patients [53.2%] delivered after treatment with nirmatrelvir and ritonavir. Twelve of these patients [48.0%] underwent cesarean delivery, 9 [75.0%] of which were scheduled. Two of 47 patients [4.3%] were hospitalized for conditions related to preexisting comorbidities.Conclusions and RelevanceIn this case series, pregnant patients who were treated with nirmatrelvir and ritonavir tolerated treatment well, although there was an unexpectedly high rate of cesarean deliveries. The lack of an increase in serious adverse effects affecting pregnant patients or offspring suggests that clinicians can use this drug combination to treat pregnant patients with SARS-CoV-2 infection.