Tixagevimab/cilgavimab for the prevention of COVID-19 in solid organ transplant recipients.

Tixagevimab/cilgavimab (tix/cil) received emergency use authorization in December 2021 for pre-exposure prophylaxis against COVID-19 in moderately to severely immunocompromised patients. Our study aimed to describe the incidence of COVID-19 infection and assess the immunologic risks associated with tix/cil in kidney, pancreas, liver, and heart transplant recipients. Retrospective chart review was completed to provide descriptive analysis. Outcomes data included COVID-19 infection, severity of COVID-19 infection, graft function, and rejection. Safety outcomes included cardiovascular (CV) and hypersensitivity events post tix/cil administration. A total of 410 transplant patients were included in the analysis: 20 heart, 92 liver, 243 kidney, 25 simultaneous pancreas/kidney, 23 simultaneous liver/kidney, and seven simultaneous heart/kidney. Twenty-seven (6.5%) patients tested positive for COVID-19 via PCR or antigen test post tix/cil. No apparent difference was observed in patients testing positive for COVID-19 by type of organ transplant (p = .122). Twenty-five of the 27 patients testing positive for COVID-19 reported symptomatic infection, only nine of whom were hospitalized. No patients were mechanically ventilated and no deaths due to COVID-19 occurred. No significant changes in graft function were observed. Clinically significant rejection was diagnosed and treated in four patients. COVID-19 breakthrough infection rates remained low in immunocompromised solid organ transplant recipients who received tix/cil. No significant immunologic risks were observed.

Direct oral anticoagulant plus antiplatelet therapy: prescribing practices and bleeding outcomes.

Concurrent antiplatelet therapy (APT) is common during warfarin therapy but is less well-documented during direct oral anticoagulant (DOAC) therapy. Combined anticoagulant and APT use has been associated with increased bleeding risk without providing additional protection against thrombosis. This study aimed to describe single-center prescribing rates of DOAC + APT as well as compare bleeding rates between DOAC monotherapy and DOAC + APT cohorts. Patients receiving DOAC therapy were evaluated for APT use at the time of hospital discharge. Patients were categorized into DOAC monotherapy and DOAC + APT cohorts. Primary outcomes included DOAC + APT prescribing rate as well as rates of major bleeding and clinically relevant non-major bleeding (CRNMB) within six months after hospital discharge. Secondary outcomes included rates of thromboembolism and all-cause mortality. Of 407 patients receiving DOAC therapy, 78 (19.2%) also received APT at hospital discharge. Common indications for APT included secondary cardiovascular event prevention (57.7%) and primary cardiovascular event prevention (29.5%). The indication for APT could not be determined in 12.8% of patients. The major bleeding rate was 1.3% for DOAC + APT and 1.2% for DOAC monotherapy (p = 0.95). The CRNMB rate was 10.2% for DOAC + APT and 6.4% for DOAC monotherapy (p = 0.23). Thromboembolism and mortality were infrequent in both cohorts. DOAC + APT was documented in approximately 1 of 5 patients. Adding APT to DOAC therapy did not significantly increase the major bleeding or CRNMB rates compared to DOAC monotherapy but the sample size limits drawing conclusions about the safety of these regimens. Targeting primary prevention or unclear indications for APT could be a focus of future interventions.