Background: Molnupiravir is an oral prodrug with antiviral activity against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Molnupiravir was initially developed for Influenza treatment, is being repurposed for the treatment of COVID-19. This study evaluates the efficacy and safety of molnupiravir in addition to the standardof-care (SOC) for the treatment of non-hospitalized patients with mild COVID-19. Methods: In this phase 3, randomized, open-label, parallel-group study, 1220 patients with laboratory-confirmed (RT-PCR positive) SARS-CoV-2 infection were enrolled across 16 centres in India and 7.3% (90/1220) patients were with one risk factor (i.e. hypertension, diabetes mellitus, obesity, hypothyroidism, hyperthyroidism) presenting a risk for progression to severe COVID-19. Non-hospitalized adults with mild COVID-19 were randomized to receive either molnupiravir 800 mg (200 mg x 4 capsules administered orally every 12 hours for 5 days) with SOC or SOC alone and followed up at day 5 (end of treatment, and days 10, 14 and 28. Standard of care was provided as per the clinical guidance for management of adult COVID-19 patients by the Government of India or as per the Investigator's discretion. The primary endpoint was the rate of hospitalization of patients from randomization till day 14. Secondary endpoints included rate of hospitalization of patients from randomization up to day 28; clinical improvement (2-point decrease in 11-point WHO Clinical Progression Scale) at days 5, 10, and 14; SARS-CoV-2 RT-PCR negativity at the end of treatment; and mortality rate at day 14 and day 28. The study is registered with the Clinical Trials Registry of India, CTRI/2021/07/034588.