BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) has changed our lives. The scientific community has been investigating re-purposed treatments to prevent disease progression in coronavirus disease (COVID-19) patients. OBJECTIVE: To determine whether ivermectin treatment can prevent hospitalization in individuals with early COVID-19. DESIGN, SETTING AND PARTICIPANTS: A randomized, double-blind, placebo-controlled study was conducted in non-hospitalized individuals with COVID-19 in Corrientes, Argentina. Patients with SARS-CoV-2 positive nasal swabs were contacted within 48 h by telephone to invite them to participate. The trial randomized 501 patients between August 19th 2020 and February 22nd 2021. INTERVENTION: Patients were randomized to ivermectin (N = 250) or placebo (N = 251) arms in a staggered dose, according to the patient's weight, for 2 days. MAIN OUTCOMES AND MEASURES: The efficacy of ivermectin to prevent hospitalizations was evaluated as primary outcome. We evaluated secondary outcomes in relationship to safety and other efficacy end points. RESULTS: The mean age was 42 years (SD +/- 15.5) and the median time since symptom onset to the inclusion was 4 days [interquartile range 3-6]. The primary outcome of hospitalization was met in 14/250 (5.6%) individuals in ivermectin group and 21/251 (8.4%) in placebo group (odds ratio 0.65; 95% confidence interval, 0.32-1.31; p = 0.227). Time to hospitalization was not statistically different between groups. The mean time from study enrollment to invasive mechanical ventilatory support (MVS) was 5.25 days (SD +/- 1.71) in ivermectin group and 10 days (SD +/- 2) in placebo group, (p = 0.019). There were no statistically significant differences in the other secondary outcomes including polymerase chain reaction test negativity and safety outcomes. LIMITATIONS: Low percentage of hospitalization events, dose of ivermectin and not including only high-risk population. CONCLUSION: Ivermectin had no significant effect on preventing hospitalization of patients with COVID-19. Patients who received ivermectin required invasive MVS earlier in their treatment. No significant differences were observed in any of the other secondary outcomes. TRIAL REGISTRATION: ClinicalTrials.gov NCT04529525 .