High Dose Ivermectin for the Early Treatment of COVID-19 (COVER Study): A Randomised, Double-Blind, Multicentre, Phase II, Dose-Finding, Proof of Concept Clinical Trial

Background: High concentrations of ivermectin demonstrated antiviral activity against SARS-CoV-2 in vitro.  Aim of this study was to assess safety and efficacy of high-dose ivermectin in reducing viral load in individuals with initial SARS-CoV-2 infection. Methods: Randomised, double-blind, multicentre, phase II, dose-finding, proof-of-concept clinical trial performed in outpatients in Italy. Participants: adults recently diagnosed with asymptomatic/oligosymptomatic SARS-CoV-2 infection, providing informed consent. Exclusion criteria: pregnant or lactating women; CNS diseases; participants under dialysis; severe medical condition with  prognosis < 6 months; warfarin treatment; antiviral/chloroquine phosphate/hydroxychloroquine treatment. Participants were assigned according to a randomized permuted block procedure to one of the following arms with allocation ratio 1:1:1: placebo (arm A); single dose ivermectin 600 μg/kg plus placebo for 5 days (arm B); single dose ivermectin 1200 μg/kg for 5 days (arm C). The pharmacist prepared the treatment according to the randomization list and on the basis of the participant’s weight. Primary outcomes: serious adverse drug reactions (SADR) and change of viral load at Day 7. The protocol was registered with ClinicalTrials.gov , NCT04438850. Findings. From 31th July, 2020 to 26th May, 2021, 32 participants were randomized to arm A, 29 to arm B and 32 to arm C. The recruitment was stopped on 10th June, because of a dramatic drop of cases. Eighty-nine participants were included in the safety analysis set, the change in viral load was calculated on 87 participants. No SADR were registered. The mean log10 viral load reduction was 2.9 in arm C (SD 1.6), 2.5 (2.2) in arm B and 2.0 (2.1) in arm A, with no significant differences (p=0.099 and 0.122 for C versus A and B versus A, respectively). Interpretation: High- dose ivermectin demonstrated safe, but did not prove efficacy to reduce viral load. Trial Registration: The protocol was registered with ClinicalTrials.gov , NCT04438850. Funding: The trial was partly funded by the Italian Ministry of Health. Declaration of Interest: None to declare. Ethical Approval: This study was approved by the national Ethics Committee of INMI – Spallanzani in Rome that is competent for all COVID-19 trials in Italy (resolution 139/2020 of 28th May, 2020), and by the Italian drug agency AIFA (resolution 136BIS/2020 of 18th May, 2020).