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Published on: August 12, 2017
A single-center review of pre-exposure prophylaxis with tixagevimab-cilgavimab in solid organ transplant recipients
Faiza Morado1, Roland Davoudi2, Pnada Kawewat-Ho2
1Department of Clinical Pharmacy, Keck Hospital of USC, University of Southern California, Los Angeles, California, USA.
Background:
Coronavirus disease 2019 (COVID-19) continues to negatively impact solid organ transplant recipients (SOTr). Data on the use of tixagevimab-cilgavimab (tix-cil) in vaccinated SOTr during circulation of Omicron and its subvariants are limited. Therefore, this single-center review was conducted to evaluate tix-cil efficacy in multiple organ transplant groups during a study period where Omicron B.1.1.529, BA.2.12.1, and BA.5 predominated.
Methods:
In this single-center retrospective study, we evaluated the incidence of COVID-19 infection in adult SOTr who did or did not receive pre-exposure prophylaxis (PrEP) with tix-cil. SOTr were included if they were at least 18 years of age and met emergency use authorization criteria for tix-cil use. The primary outcome analyzed was the incidence of COVID-19 infection.
Results:
Ninety SOTr met inclusion criteria and comprised of two groups, tix-cil PrEP (n = 45) and no tix-cil PrEP (n = 45). Of SOTr who received tix-cil PrEP, three (6.7%) developed COVID-19 infection, compared to eight (17.8%) in the no tix-cil PrEP group (p = .20). Of the 11 SOTr diagnosed with COVID-19, 15 (82.2%) were fully vaccinated against COVID-19 prior to transplantation. Moreover, 18.2% and 81.8% of the COVID-19 cases observed were asymptomatic and mild-to-moderate, respectively.
Discussion:
Our study results, which included months when BA.5 was in increased circulation, suggest no significant difference in COVID-19 infection with or without use of tix-cil PrEP in our solid organ transplant groups. As the COVID-19 pandemic continues to evolve, clinical utility of tix-cil should be evaluated against new, emerging strains.
Insights
Tixagevimab-cilgavimab (tix-cil) did not significantly reduce COVID-19 infection rates in vaccinated solid organ transplant recipients during Omicron variant circulation. Further evaluation against emerging strains is recommended.
Area of Science:
- Immunology
- Infectious Diseases
- Transplant Medicine
Background:
- Solid organ transplant recipients (SOTr) remain vulnerable to COVID-19.
- Limited data exists on tixagevimab-cilgavimab (tix-cil) efficacy in vaccinated SOTr during Omicron variant predominance.
- This study addresses the need for data on tix-cil in SOTr during specific Omicron subvariant circulation.
Purpose of the Study:
- To evaluate the efficacy of tixagevimab-cilgavimab (tix-cil) as pre-exposure prophylaxis (PrEP) in vaccinated solid organ transplant recipients (SOTr).
- To assess COVID-19 infection incidence in SOTr who received tix-cil PrEP compared to those who did not.
- To analyze tix-cil effectiveness during the circulation of Omicron (B.1.1.529), BA.2.12.1, and BA.5 subvariants.
Main Methods:
- Single-center retrospective study including adult SOTr meeting tix-cil emergency use criteria.
- Comparison of COVID-19 infection incidence between SOTr receiving tix-cil PrEP (n=45) and those not receiving PrEP (n=45).
- Primary outcome: incidence of COVID-19 infection post-tix-cil administration or during the study period.
Main Results:
- Three (6.7%) SOTr in the tix-cil PrEP group developed COVID-19 compared to eight (17.8%) in the no PrEP group (p=0.20).
- Of 11 COVID-19 cases, 82.2% were fully vaccinated prior to transplantation.
- The majority of COVID-19 cases (81.8%) were asymptomatic or mild-to-moderate.
Conclusions:
- Tixagevimab-cilgavimab (tix-cil) PrEP showed no significant difference in preventing COVID-19 infection in solid organ transplant recipients during Omicron variant circulation.
- The study included periods of increased BA.5 variant circulation, providing relevant data.
- Ongoing evaluation of tix-cil's clinical utility against new and emerging SARS-CoV-2 strains is crucial.
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