The primary objective of the Phase 2 study is to assess the virologic efficacy of REGN10933+REGN10987 across different intravenous and subcutaneous doses compared to placebo.

The secondary objectives of the study are:

To evaluate additional indicators of virologic efficacy of REGN10933+REGN10987 compared to placebo

To evaluate the safety and tolerability of REGN10933+REGN10987 compared to placebo

To assess the concentrations of REGN10933 and REGN10987 in serum over time

To assess the immunogenicity of REGN10933 and REGN10987

Results

On November 9, 2021, MedRxiv published non-peer-reviewed results.

All REGEN-COV treatments showed significant (p<0·001 versus pooled placebo) virologic reduction through day 7. Least-squares mean differences in TWACB viral load for the treatments versus placebo ranged from –0·56 to –0·71 log10 copies/mL. Each REGEN-COV treatment showed significant (p<0·001 versus pooled placebo) and similar virologic reduction through day 7. There were no safety concerns, dose-related safety findings, grade ≥2 infusion related/hypersensitivity reactions, grade ≥3 injection-site reactions, nor fatalities. Two serious adverse events not related to COVID-19 or the study drug were reported.

Conclusion

In asymptomatic and low-risk symptomatic SARS-CoV-2-infected outpatients seronegative for antibodies against SARS-CoV-2 at baseline, REGEN-COV significantly and comparably reduced viral load at all IV and SC doses.