LB1528. Results from ACTIV-6: A Decentralized, Double-Blinded, Randomized, Placebo-Controlled Platform Trial of Repurposed Drugs for the Treatment of Mild-to-Moderate COVID-19

Abstract Background The effectiveness of fluvoxamine to shorten symptom duration or prevent hospitalization among outpatients with mild-to-moderate coronavirus 2019 (COVID-19) is unclear. Tolerability has also been identified as a potential limiting factor for 100 mg twice daily of fluvoxamine. We evaluated the efficacy of low-dose fluvoxamine 50 mg twice daily for 10 days compared with placebo for the treatment of early mild-to-moderate COVID-19. Methods ACTIV-6 is an ongoing, decentralized, double-blind, randomized, placebo-controlled platform trial testing repurposed medications in outpatients with confirmed SARS-CoV-2 infection. Non-hospitalized adults aged ≥ 30 years, experiencing ≥ 2 symptoms of acute infection for ≤ 7 days were randomized to fluvoxamine 50 mg twice daily for 10 days or placebo. The primary outcome was time to sustained recovery, defined as the third of 3 consecutive days without symptoms. Secondary outcomes included composites of hospitalization or death with or without urgent care or emergency department visit by day 28. Results Of those eligible for the fluvoxamine arm, 675 were randomized to and received fluvoxamine; 619 received concurrent placebo. Sixty-six percent of the study population reported at least 2 doses of a COVID-19 vaccine. There was no evidence of improvement in time to recovery with fluvoxamine compared with placebo (hazard ratio [HR] 0.96, 95% credible interval [CrI] 0.86–1.06; posterior probability for benefit [HR > 1]=0.2). Sixteen participants (2.4%) in the fluvoxamine arm had urgent care or emergency department visits or were hospitalized compared with 11 (1.8%) in the pooled, concurrent placebo arm (HR 1.5, 95% CrI 0.5–3.0; posterior probability for benefit [HR < 1]=0.1725). No participant in either arm was hospitalized, and no deaths occurred. Adverse events were uncommon in both arms. Conclusion Treatment with low-dose fluvoxamine 50 mg dosed twice daily for 10 days did not result in improved time to recovery among outpatients with COVID-19 in the United States during the delta and omicron variant surges. Disclosures All Authors: No reported disclosures.