The Food and Drug Administration (FDA) has revised the fact sheet for Evusheld (tixagevimab co-packaged with cilgavimab) to include a recommendation for repeat dosing every 6 months for the preexposure prophylaxis of COVID-19.

Evusheld is a combination of 2 long-acting monoclonal antibodies designed to bind to distinct sites on the SARS-CoV-2 spike protein. The product is authorized for emergency use for individuals who are not currently infected with SARS-CoV-2 and who have not had a known recent exposure to an individual infected with SARS-CoV-2, and:

  • Who have moderate to severe immune compromise due to a medical condition or receipt of immunosuppressive medications or treatments and may not mount an adequate immune response to COVID-19 vaccination; or
  • For whom vaccination with any available COVID-19 vaccine, according to the approved or authorized schedule, is not recommended due to a history of severe adverse reaction to a COVID-19 vaccine(s) and/or COVID19 vaccine component(s).

Previously, it was unclear what the duration of protection with Evusheld was as the clinical trial data supporting the authorization came before the emergence of the Omicron subvariants.

The new recommendation for repeat dosing is based on data from a substudy of the PROVENT trial (ClinicalTrials.gov Identifier:  NCT04625725). Pharmacokinetic and pharmacodynamic modeling suggest that activity against currently circulating subvariants (Omicron BA.2, BA.2.12.1, BA.4, and BA.5) appears to be retained for 6 months at drug concentrations achieved following an Evusheld dose of tixagevimab 300mg and cilgavimab 300mg. As such, a dosing interval of every 6 months has been recommended for patients requiring ongoing protection.

There are currently no efficacy data available for repeat dosing and safety data are also limited. In a press release, the FDA stated that it will continue to monitor the neutralizing activity of Evusheld against emerging SARS-CoV-2 variants and will alert the public as new information becomes available.

The revised Evusheld Fact Sheet for Healthcare Providers can be found here.

Reference

FDA authorizes revisions to Evusheld dosing. News release. June 29, 2022. https://www.fda.gov/drugs/drug-safety-and-availability/fda-authorizes-revisions-evusheld-dosing