Phase II study of bemnifosbuvir in high-risk participants in a hospital setting with moderate COVID-19

Background: Bemnifosbuvir, a novel, oral, nonmutagenic, nonteratogenic nucleotide analogue inhibits SARS-CoV-2 replication in vitro. Materials & methods: Adults in hospital settings with moderate COVID-19 were randomized 1:1 bemnifosbuvir/placebo. Study amended to two-parts after interim analysis; part B enrollment limited owing to evolving standard of care. Results: Although the study ended early and did not meet the primary efficacy end point, bemnifosbuvir was well tolerated and did not contribute to all-cause mortality. Compared with placebo, bemnifosbuvir treatment resulted in 0.61 log(10) greater viral load mean change on day 2; trend sustained through day 8. Treatment-emergent adverse events were similar in both groups; most were mild/moderate, unrelated to study drug. Conclusion: Our results suggest a potential role for bemnifosbuvir in blunting COVID-19 progression.