COVID-19 convalescent plasma for the treatment of immunocompromised patients

In this systematic review and meta-analysis, the authors assess reports of clinical experiences of patients with COVID-19 and immunosuppression who were treated with specific neutralizing antibodies via convalescent plasma transfusion.

Patients who are immunocompromised have increased risk for morbidity and mortality associated with coronavirus disease 2019 (COVID-19) because they less frequently mount antibody responses to vaccines. Although neutralizing anti-spike monoclonal-antibody treatment has been widely used to treat COVID-19, evolutions of SARS-CoV-2 have been associated with monoclonal antibody-resistant SARS-CoV-2 variants and greater virulence and transmissibility of SARS-CoV-2.

Randomized clinical trials, matched cohort studies, and case report or series on COVID-19 convalescent plasma use in patients who are immunocompromised were included. The electronic search yielded 462 unique records, of which 199 were considered for full-text screening.

Key points of the review:

  • Several scientific societies have revised their guidelines to recommend the use of COVID-19 convalescent plasma in patients who are immunocompromised, especially after concerns related to the prevalence of monoclonal antibody-resistant SARS-CoV-2 variants.
  • Transfusion of COVID-19 convalescent plasma was associated with a mortality benefit among hospitalized patients with primary or secondary immunosuppression and COVID-19.
  • Antibody-based therapies function primarily as antiviral agents and are much less likely to be effective in individuals who are in the inflammatory phase.
  • High-titer and vax-plasma are now widely available from regular donors and retains higher neutralizing antibody titers and efficacy against most SARS-CoV-2 variants.
  • Clinical use of COVID-19 convalescent plasma and vax-plasma in patients who are immunocompromised and have COVID-19 warrants further investigation.