COVID-19 Evidence Alerts
from McMaster PLUSTM

Current best evidence for clinical care (more info)

Treatment Das S, Bhowmick S, Tiwari S, et al. An Updated Systematic Review of the Therapeutic Role of Hydroxychloroquine in Coronavirus Disease-19 (COVID-19). Clin Drug Investig. 2020 Jul;40(7):591-601. doi: 10.1007/s40261-020-00927-1.

BACKGROUND AND OBJECTIVE: The world is currently experiencing the Coronavirus Disease-19 (COVID-19) pandemic. There is no approved drug for the definitive treatment of the disease. Various drugs are being tried for the treatment of COVID-19, including hydroxychloroquine (HCQ). This study was performed to systematically review the therapeutic role of HCQ in COVID-19 from the available literature.

METHODS: PubMed, Embase,, ICTRP (WHO), Cochrane Library databases, and two pre-print servers ( and Research Square) were searched for clinical studies that evaluated the therapeutic role of HCQ on COVID-19 until 10 May 2020. The available studies were critically analyzed and the data were extracted.

RESULTS: A total of 663 articles were screened and 12 clinical studies (seven peer-reviewed and published studies and five non-peer-reviewed studies from pre-print servers) with a total sample size of 3543 patients were included. Some of the clinical studies demonstrated good virological and clinical outcomes with HCQ alone or in combination with azithromycin in COVID-19 patients, although the studies had major methodological limitations. Some of the other studies showed negative results with HCQ therapy along with the risk of adverse reactions.

CONCLUSION: The results of efficacy and safety of HCQ in COVID-19, as obtained from the clinical studies, are not satisfactory, although many of these studies had major methodological limitations. Stronger evidence from well-designed robust randomized clinical trials is required before conclusively determining the role of HCQ in the treatment of COVID-19. Clinical prudence is required in advocating HCQ as a therapeutic armamentarium in COVID-19.

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

Emergency Medicine rater

Unfortunately this review simply reflects what we already know. The data are mixed and the quality of the studies so poor that we cannot determine if hydroxychloroquine has any role in the treatment of Covid-19, or if it’s potential to harm exceeds potential benefits.

Emergency Medicine rater

This information is important not only for clinicians in their treating of patients, but also for themselves given the prophylaxis studies. This review shows the literature does not currently support either.

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

Treatment of COVID-19 has been controversial. Many physicians are reading the original articles as they appear; it is already well known that there is no definite treatment and majority of the earlier studies have many limitations. This systematic review is premature.

General Internal Medicine-Primary Care(US) rater

Although the appropriate conclusion remains that we do not know whether hydroxychloroquine is beneficial in SARS-CoV2 infection, it is important to have an analysis of extant clinical trials on this rapidly developing topic of global importance.

Public Health rater

This is a very important review. The use of Hydroxychloroquine were very promising in the early of COVID-19 pandemic. This review showed that most of the trials have methodological flaws. The use of systematic ways on finding the articles are the strength of this review. The authors do not explain the critical appraisal process in detail. Who performed the appraisal? How they they deal with a different opinion between raters? Further trials with good methodological aspects are warranted in the future.

Public Health rater

This is a very important paper. The available information has been controversial, and even troublesome (like the recent retraction of a paper in Lancet because the authors did not agree to an independent evaluation of the database).

Respirology/Pulmonology rater

The results of this review clearly show that we currently do not have sufficient evidence on the efficacy of HCQ in COVID-19. The adverse effects of HCQ administration in COVID-19 patients is also of serious concern. High quality evidence from well-designed robust randomised trials are required before determining the role of HCQ in the treatment of COVID-19.