Regeneron, Eli Lilly Both Request Emergency Approval for COVID-19 Antibody Therapies

Both Regeneron and Eli Lilly have filed for emergency use authorization (EUA) from the FDA for each of their investigational antibody therapies for the treatment of coronavirus disease 2019 (COVID-19).^1,2

Regeneron’s antibody cocktail, REGN-COV2, which is a combination of 2 monoclonal antibodies (REGN10933 and REGN10987), was one of the treatments given to President Donald Trump following his diagnosis of COVID-19.

Last week, Regeneron reported that the experimental treatment reduced viral levels and improved symptoms in non-hospitalized patients with COVID-19, according to data from a descriptive analysis of a phase 1/2/3 trial. The ongoing, randomized, double-blind trial is evaluating the effect of adding REGN-COV2 to usual standard of care compared with adding placebo to standard of care.³

The descriptive analysis included the first 275 patients enrolled in the trial and was designed to evaluate anti-viral activity with REGN-COV2 and identify patients most likely to benefit from treatment. Patients were randomized to receive a 1-time infusion of 8 grams of REGN-COV2 (high dose), 2.4 grams of REGN-COV2 (low dose), or placebo. All patients in the trial had laboratory-confirmed COVID-19 that was being treated in the outpatient setting.³

According to Regeneron, the key data findings included:³

• Serological status highly correlated with baseline viral load. Seropositive patients had much lower levels of virus at baseline, and rapidly achieved viral loads approaching lowest levels quantifiable, even without treatment. Seronegative patients had substantially higher viral loads at baseline and cleared virus more slowly without treatment.
• Serological status at baseline also predicted how rapidly patients had alleviation of their COVID-19 clinical symptoms. In the untreated group, seropositive patients had a median time to alleviation of symptoms of 7 days, compared with seronegative patents who had a median time to alleviation of symptoms of 13 days.
• REGN-COV2 rapidly reduced viral load through day 7 in seronegative patients (key virologic end point).
• Patients with increasingly higher baseline viral levels had correspondingly greater reductions in viral load at day 7 with REGN-COV2 treatment.
• Patients who were seronegative and/or had higher baseline viral levels also had greater benefits in terms of symptom alleviation.
• There were a small number of medically-attended visits given that most non-hospitalized patients recover well at home.
• Both doses were well-tolerated.

Regeneron said in the statement that doses are currently available for approximately 50,000 patients, but the company anticipates enough doses for 300,000 patients in total within the next few months.¹

Eli Lilly also announced submission of its request for emergency approval for its single monoclonal antibody therapy, which was based on new interim data and previous clinical trial results. The therapy, bamlanivimab (previously known as LY-CoV555), is being evaluated for use in higher-risk patients who have been recently diagnosed with mild-to-moderate COVID-19.²

According to interim data from the BLAZE-1 clinical trial, the combination antibody therapy of bamlanivimab and etesevimab (previously known as LY-CoV016) reduced viral load, symptoms, and hospitalizations or emergency room visits associated with COVID-19. For the monotherapy, Lilly is focused on the 700-mg dose of bamlanivimab, since similar clinical effects were seen across all dose levels tested in the study.²

“We believe the data generated to date provide sufficient evidence that both monotherapy and combination therapy may be effective to treat COVID-19 in patients with a high risk for serious outcomes,” Daniel Skovronsky, MD, PhD, Lilly’s chief scientific officer and president of Lilly Research Laboratories, said in a statement.²

The company expects to submit an EUA request for its combination antibody therapy in November.²

References:

1. Statement on REGN-COV2 Emergency Use Authorization Request. Company statement. Regeneron; October 7, 2020. Accessed October 8, 2020. https://newsroom.regeneron.com/static-files/6feab76b-176d-402d-bf30-d40462e68b7b​
2. Lilly provides comprehensive update on progress of SARS-CoV-2 neutralizing antibody programs. News release. Eli Lilly; October 7, 2020. Accessed October 8, 2020. https://investor.lilly.com/news-releases/news-release-details/lilly-provides-comprehensive-update-progress-sars-cov-2​
3. Regeneron’s REGN-COV2 Antibody Cocktails Reduced Viral Levels and Improved Symptoms in Non-Hospitalized COVID-19 Patients. News release. Regeneron; September 29, 2020. Accessed October 8, 2020. https://investor.regeneron.com/news-releases/news-release-details/regenerons-regn-cov2-antibody-cocktail-reduced-viral-levels-and​