Japan Becomes First Country to Approve Regeneron Antibody Cocktail (casirivimab and imdevimab) for the Treatment of Mild to Moderate COVID-19

Regeneron Pharmaceuticals, Inc. (NASDAQ: REGN) today announced that Japan's Ministry of Health, Labour and Welfare (MHLW) has approved Regeneron's casirivimab and imdevimab antibody cocktail to treat patients with mild to moderate COVID-19. This marks the first time the antibody cocktail, known as REGEN-COVTM in the U.S. and Ronapreve™ in other countries, has received a full approval to treat COVID-19. Emergency or temporary pandemic use authorizations are currently in place in more than 20 countries, including in the U.S., European Union, India, Switzerland and Canada. 

"After a record-speed discovery and development program, we are pleased that our COVID-19 antibody cocktail continues to reach even more people around the globe," said George D. Yancopoulos, M.D., Ph.D., President and Chief Scientific Officer of Regeneron. "Unfortunately, this virus continues to spread despite increasing rates of vaccination, and there will be an important continued need for treatments that remain active against the variants of concern."  

In Japan, the antibody cocktail was granted a Special Approval Pathway under article 14-3 of the Pharmaceuticals and Medical Devices Act. The approval was based on results from a Phase 3 trial in high-risk non-hospitalized patients, which showed the antibody cocktail reduced the risk of hospitalization or death by 70%, as well as results from a Phase 1 trial that examined the safety, tolerability and pharmacokinetics in Japanese people. 

Regeneron invented REGEN-COV and is collaborating with Roche to increase global supply of the antibody cocktail, with Roche primarily responsible for development and distribution outside the U.S. In December 2020, Chugai obtained development and exclusive commercialization rights in Japan from Roche, and is working with the Japanese government to ensure an appropriate and timely supply of the antibody cocktail.

The development and manufacturing of REGEN-COV have been funded in part with federal funds from the Biomedical Advanced Research and Development Authority (BARDA), part of the U.S. Department of Health and Human Services' Office of the Assistant Secretary for Preparedness and Response, under OT number: HHSO100201700020C.

About the REGEN-COV Antibody Cocktail

REGEN-COV (casirivimab and imdevimab) is a cocktail of two monoclonal antibodies that was designed specifically to block infectivity of SARS-CoV-2, the virus that causes COVID-19, using Regeneron's proprietary VelocImmune® and VelociSuite® technologies. The two potent, virus-neutralizing antibodies that form the cocktail bind non-competitively to the critical receptor binding domain of the virus's spike protein, which diminishes the ability of mutant viruses to escape treatment and protects against spike variants that have arisen in the human population, as detailed in Science.

Over the past few months Regeneron has announced results from multiple Phase 3 trials demonstrating the ability of REGEN-COV to reduce the burden of COVID-19, from prevention through to hospitalization. This includes trials assessing the ability of REGEN-COV to treat outpatients already infected with SARS-COV-2 (including symptomatic outpatients and recently infected asymptomatic patients) and in certain hospitalized patients, including the RECOVERY trial. 

Multiple analyses, including a recent publication in Cell, have shown that REGEN-COV retains potency against the main variants of concern circulating within the U.S.; consequently, REGEN-COV remains available for use in all 50 states. REGEN-COV retains potency against variants including Delta (B.1.162.2; first identified in India), Gamma (P.1; first identified in Brazil), Beta (B.1.351; first identified in South Africa). 

REGEN-COV is available throughout the U.S. – information on availability in your area is available from the Department of Health and Human Services and the National Infusion Center Association. REGEN-COV has not been approved by the U.S. Food and Drug Administration (FDA), but is currently authorized in the U.S. under an Emergency Use Authorization (EUA) to treat mild-to-moderate COVID-19 in adults and pediatric patients (12 years of age and older weighing ≥40 kg) with positive results of direct SARS-CoV-2 viral testing, and who are at high risk for progression to severe COVID-19, including hospitalization or death. This use is authorized only for the duration of the declaration that circumstances exist justifying the authorization of the emergency use under section 564(b)(1) of the Act, 21 U.S.C. § 360bbb-3(b)(1), unless the authorization is terminated or revoked sooner. REGEN-COV is not authorized for use in patients who are hospitalized due to COVID-19 or require oxygen therapy, or for people currently using chronic oxygen therapy because of an underlying comorbidity who require an increase in baseline oxygen flow rate due to COVID-19.

In the U.S., REGEN-COV can be administered by intravenous infusion (as short as 20 minutes) or by subcutaneous injection (4 injections), which is an alternative when intravenous infusion is not feasible and would lead to a delay in treatment. It is now authorized as a co-formulated single vial, or in individual vials to be administered together. 

Regeneron and Roche share a commitment to making the antibody cocktail available to COVID-19 patients around the globe and will support access in low- and lower-middle-income countries through drug donations to be made in partnership with public health organizations.

About Regeneron's VelocImmune Technology

Regeneron's VelocImmune technology utilizes a proprietary genetically engineered mouse platform endowed with a genetically humanized immune system to produce optimized fully human antibodies. When Regeneron's President and Chief Scientific Officer George D. Yancopoulos was a graduate student with his mentor Frederick W. Alt in 1985, they were the first to envision making such a genetically humanized mouse, and Regeneron has spent decades inventing and developing VelocImmune and related VelociSuite technologies. Dr. Yancopoulos and his team have used VelocImmune technology to create approximately a quarter of all original, FDA-approved fully human monoclonal antibodies currently available. This includes REGEN-COV (casirivimab and imdevimab), Dupixent® (dupilumab), Libtayo®(cemiplimab-rwlc), Praluent® (alirocumab), Kevzara® (sarilumab), Evkeeza® (evinacumab-dgnb) and Inmazeb™ (atoltivimab, maftivimab and odesivimab-ebgn).