Overview

The incentive structure for being contact traced recently changed dramatically.

Contact tracing traditionally uses quarantine to stop the spread of infectious disease, but at substantial financial, logistical, educational, and social costs. Today, fully vaccinated contacts are no longer required to quarantine in the U.S. and many other countries, but are asked merely to get tested and monitor symptoms. Being traced thus makes early diagnosis of COVID-19 more likely, and with it, earlier treatment that might be more effective. Indeed, post-exposure prophylactic treatment can prevent an initial infection event from progressing to COVID-19 symptoms, preventing both individual disease and community spread. This panel will feature two speakers, one describing the clinical data on post-exposure prophylaxis with monoclonal antibodies against COVID-19, the other its epidemiological consequences.

Agenda

COVID-19 Prevention and Early Treatment with Subcutaneous Administration of the Monoclonal Antibodies Casirivimab + Imdevimab

Meagan O’Brien, Regeneron Pharmaceuticals, will discuss the clinical data on post-exposure prophylaxis with monoclonal antibodies against COVID-19....

As a complement to vaccines, antiviral treatments with more convenient routes of administration are needed for immediate protection to prevent COVID-19 and to reduce viral carriage. We evaluated the efficacy and safety of subcutaneous casirivimab and imdevimab antibody combination (REGEN-COV) to prevent COVID-19 in household contacts of individuals with COVID-19 in a randomized, double-blind, placebo-controlled, phase 3 study, including participants who were both SARS-CoV-2 RT-qPCR-negative and -positive at baseline. Subcutaneous REGEN-COV 1200mg prevented symptomatic COVID-19 and reduced the duration of high viral load and symptoms. REGEN-COV is now authorized for emergency use in the US, among other countries, for outpatient treatment of mild to moderate COVID-19 and for post-exposure prophylaxis in certain high-risk individuals.

Health Impact and Cost of COVID-19 Post-Exposure Prophylaxis within Households
Jennifer Ross, University of Washington, will discuss the epidemiological consequences of post-exposure prophylaxis with monoclonal antibodies.

Background: We aimed to estimate the impact and health system cost of implementing post-exposure prophylaxis against household exposure to COVID-19 with monoclonal antibodies.

Methods: We developed a decision-analytical model analysis of results from a recent randomized controlled trial with complementary data on household demographic structure, vaccine coverage, and COVID-19 confirmed case counts for the representative month of May, 2021.

Results: In a month of similar intensity to May, 2021, in the USA, a monoclonal antibody post-exposure prophylaxis program reaching 50% of exposed unvaccinated household members aged 50+, would avert 1,813 (1,171 – 2,456) symptomatic infections, 526 (343 - 716) hospitalizations, and 83 (56 - 116) deaths. Assuming the unit cost of administering the intervention was US$ 1,264, this program would save the health system US$ 3,055,202 (-14,034,632 - 18,787,692).

Conclusions: Currently in the United States, health system and public health actors have an opportunity to improve health and reduce costs through COVID-19 post-exposure prophylaxis with monoclonal antibodies. Read more