Effects of Casirivimab/Imdevimab Monoclonal Antibody Treatment among Vaccinated Patients Infected by SARS-CoV-2 Delta Variant

Viruses. 2022 Mar 21;14(3):650. doi: 10.3390/v14030650.

Abstract

There is a growing interest in using monoclonal antibodies (mAbs) in the early stages of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection to prevent disease progression. Little is known about the efficacy of mAbs against the delta variant of concern and its clinical presentations. We evaluated the effect of casirivimab/imdevimab treatment among five delta vaccine breakthrough patients. Symptomatic non-hospitalized vaccinated patients were submitted to nasopharyngeal swabs for the detection of SARS-CoV-2 and Next-Generation Sequencing (NGS). Blood analysis and chest Computed Tomography were also performed. A cocktail of casirivimab/imdevimab was administrated, and patients were monitored weekly. Clinical evolution was evaluated by the regression of the symptoms, negative results by real-time RT-PCR, and by the need of hospitalization: these aspects were considered as significant outcomes. In four cases, symptom reversion and viral load reduction were observed within 2 days and 7 days after mAbs treatment, respectively. Only one case, suffering from thymoma, was hospitalized 2 days later because of respiratory failure, which reverted within 18 days. mAbs treatment seems to be safe and effective against the delta variant and its clinical manifestations.

Keywords: B.1.617.2; SARS-CoV-2; casirivimab/imdevimab; delta variant; monoclonal antibody treatment; variants of concern.

MeSH terms

  • Antibodies, Monoclonal / therapeutic use
  • Antibodies, Monoclonal, Humanized
  • COVID-19 Drug Treatment*
  • Humans
  • SARS-CoV-2* / genetics

Substances

  • Antibodies, Monoclonal
  • Antibodies, Monoclonal, Humanized
  • imdevimab
  • casirivimab

Supplementary concepts

  • SARS-CoV-2 variants