COVID-19 Evidence Alerts
from McMaster PLUSTM

Current best evidence for clinical care (more info)

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Treatment Kashour Z, Riaz M, Garbati MA, et al. Efficacy of chloroquine or hydroxychloroquine in COVID-19 patients: a systematic review and meta-analysis. J Antimicrob Chemother. 2021 Jan 1;76(1):30-42. doi: 10.1093/jac/dkaa403.

OBJECTIVES: Clinical studies of chloroquine (CQ) and hydroxychloroquine (HCQ) in COVID-19 disease reported conflicting results. We sought to systematically evaluate the effect of CQ and HCQ with or without azithromycin on outcomes of COVID-19 patients.

METHODS: We searched multiple databases, preprints and grey literature up to 17 July 2020. We pooled only adjusted-effect estimates of mortality using a random-effect model. We summarized the effect of CQ or HCQ on viral clearance, ICU admission/mechanical ventilation and hospitalization.

RESULTS: Seven randomized clinical trials (RCTs) and 14 cohort studies were included (20 979 patients). Thirteen studies (1 RCT and 12 cohort studies) with 15 938 hospitalized patients examined the effect of HCQ on short-term mortality. The pooled adjusted OR was 1.05 (95% CI 0.96-1.15, I2 = 0%). Six cohort studies examined the effect of the HCQ+azithromycin combination with a pooled adjusted OR of 1.32 (95% CI 1.00-1.75, I2 = 68.1%). Two cohort studies and four RCTs found no effect of HCQ on viral clearance. One small RCT demonstrated improved viral clearance with CQ and HCQ. Three cohort studies found that HCQ had no significant effect on mechanical ventilation/ICU admission. Two RCTs found no effect for HCQ on hospitalization risk in outpatients with COVID-19.

CONCLUSIONS: Moderate certainty evidence suggests that HCQ, with or without azithromycin, lacks efficacy in reducing short-term mortality in patients hospitalized with COVID-19 or risk of hospitalization in outpatients with COVID-19.

Discipline / Specialty Area Score
Family Medicine (FM)/General Practice (GP)
General Internal Medicine-Primary Care(US)
Hospital Doctor/Hospitalists
Internal Medicine
Infectious Disease
Intensivist/Critical Care
Comments from MORE raters

Family Medicine (FM)/General Practice (GP) rater

"Our findings of lack of efficacy of HCQ in the inpatient and outpatient clinical setting despite its effective in vitro inhibitory actions against SARS-CoV-2 virus is consistent with previous observations with other viral illnesses". Numerous studies demonstrated significant in vitro inhibitory effects of CQ/HCQ against coronaviruses and non-coronaviruses.

Hospital Doctor/Hospitalists rater

This is a very relevant study especially for hospitalists and intensivists who are directly involved in care of COVID patients. This study will definitely reduce the confusion around utility of hydroxychloroquine for COVID-19 patients. Overall, it is a useful article and I want to congratulate the authors for this work.

Infectious Disease rater

The difference of this systematic review is the greater number of randomized clinical trials and observational studies in which the effectiveness of HCQ and QC in COVID-19 was assessed. However, the results and the conclusion of the manuscript do not bring any new information to what is already known about the ineffectiveness of drugs.

Infectious Disease rater

This is good analysis and very relevant for physicians treating COVID.