A month after moving its COVID-19 antibody cocktail into human trials, Regeneron is starting a phase 3 study to see whether the drug can ward off infection in people exposed to COVID-19 patients.
To be conducted with the National Institute of Allergy and Infectious Diseases, the trial aims to enroll 2,000 patients through about 100 sites in the U.S. It will study whether the cocktail, dubbed REGN-COV2, can prevent infections in uninfected people who have come into close contact with COVID-19 patients, including the housemates of patients.
Last month, Regeneron started two adaptive phase 1/2/3 studies to test the antibody cocktail as a treatment for hospitalized and non-hospitalized patients. The phase 3 prevention study comes after a data monitoring committee gave a thumbs-up to early safety data from the phase 1 portions of those trials. Regeneron has also started the phase 2/3 part of those studies, which, together, aim to enroll nearly 3,000 patients across 150 sites in the U.S., Brazil, Mexico and Chile. The trials will assess virologic and clinical endpoints.
FDA Authorizes First Tests for Measuring COVID-19 Antibody Amounts
The FDA authorized its first serology tests designed to estimate the numbers of coronavirus antibodies in a person’s bloodstream, instead of simply providing a positive or negative result on whether they are present.
While it is still not known how long COVID-19 antibodies linger following an infection—or what levels may be necessary to provide protective immunity, and in what way—these tests can be used to identify people with a strong immune system response to the virus.
Since early April, the FDA has officially greenlit 33 antibody tests, all of which are designed to provide a simple yes-or-no. The two latest diagnostics are new versions of previous assays developed by Siemens Healthineers, under the company’s Atellica and ADVIA Centaur labels, which were first authorized by the agency in late May as total antibody tests.
They provide what the company and the FDA describe as “semi-quantitative” readings of IgG antibodies, giving an estimate of their number instead of a precise measurement. IgG antibodies typically appear in the blood in the weeks after symptoms begin to show, and can be found much longer after an infection compared to other types of antibodies detected by previous tests.