Single-dose oral ivermectin in mild and moderate COVID-19 (RIVET-COV): A single-centre randomized, placebo-controlled trial

Published:August 24, 2021DOI:



      Ivermectin is an antiparasitic drug which has in-vitro efficacy in reducing severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) viral load. Hence, Ivermectin is under investigation as a repurposed agent for treating COVID-19.


      In this pilot, double blind, randomized controlled trial, hospitalized patients with mild-to-moderate COVID-19 were assigned to a single oral administration of an elixir formulation of Ivermectin at either 24 mg or 12 mg dose, or placebo in a 1:1:1 ratio. The co-primary outcomes were conversion of RT-PCR to negative result and the decline of viral load at day 5 of enrolment. Safety outcomes included total and serious adverse events. The primary outcomes were assessed in patients who had positive RT-PCR at enrolment (modified intention-to-treat population). Safety outcomes were assessed in all patients who received the intervention (intention-to-treat population).


      Among the 157 patients randomized, 125 were included in modified intention-to-treat analysis. 40 patients each were assigned to Ivermectin 24 mg and 12 mg, and 45 patients to placebo. The RT-PCR negativity at day 5 was higher in the two Ivermectin arms but failed to attain statistical significance (Ivermectin 24 mg, 47.5%; 12 mg arm, 35.0%; and placebo arm, 31.1%; p-value = 0.30). The decline of viral load at day 5 was similar in each arm. No serious adverse events occurred.


      In patients with mild and moderate COVID-19, a single oral administration of Ivermectin did not significantly increase either the negativity of RT-PCR or decline in viral load at day 5 of enrolment compared with placebo.


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