A systematic review of the prophylactic role of chloroquine and hydroxychloroquine in coronavirus disease-19 (COVID-19)

Int J Rheum Dis. 2020 May;23(5):613-619. doi: 10.1111/1756-185X.13842. Epub 2020 Apr 27.


Objective: The pandemic coronavirus disease-19 (COVID-19) has pushed the global healthcare system to a crisis and amounted to a huge economic burden. Different drugs for prophylaxis against COVID-19 including chloroquine (CQ) or hydroxychloroquine (HCQ) have been tried. This study was performed to systematically review the role of CQ and HCQ in preventing the spread of COVID-19.

Methods: PubMed, EMBASE, ClinicalTrials.gov, International Clinical Trials Registry Platform and Cochrane Library databases were searched for studies that evaluated the prophylactic role of CQ or HCQ on SARS-CoV-2 (pre-clinical studies) or COVID-19 (clinical studies) until 30 March 2020. The available literature was critically appraised.

Results: A total of 45 articles were screened and 5 (3 in vitro pre-clinical studies and 2 clinical opinions) were included. The pre-clinical studies showed the prophylactic effects of CQ and HCQ against SARS-CoV-2. On the other hand, the clinical opinions advocated the prophylactic use of CQ and HCQ against COVID-19. However, no original clinical studies on the prophylactic role of CQ or HCQ on COVID-19 were available.

Conclusion: Although pre-clinical results are promising, to date there is a dearth of evidence to support the efficacy of CQ or HCQ in preventing COVID-19. Considering potential safety issues and the likelihood of imparting a false sense of security, prophylaxis with CQ or HCQ against COVID-19 needs to be thoroughly evaluated in observational studies or high-quality randomized controlled studies.

Keywords: COVID-19; SARS-CoV-2; chloroquine; high-risk; hydroxychloroquine; prevention.

Publication types

  • Systematic Review

MeSH terms

  • Animals
  • Antiviral Agents / adverse effects
  • Antiviral Agents / therapeutic use*
  • Betacoronavirus / drug effects*
  • Betacoronavirus / pathogenicity
  • COVID-19
  • COVID-19 Drug Treatment
  • Chloroquine / adverse effects
  • Chloroquine / therapeutic use*
  • Coronavirus Infections / drug therapy
  • Coronavirus Infections / prevention & control*
  • Coronavirus Infections / transmission
  • Coronavirus Infections / virology
  • Evidence-Based Medicine
  • Humans
  • Hydroxychloroquine / adverse effects
  • Hydroxychloroquine / therapeutic use*
  • Pandemics / prevention & control*
  • Patient Safety
  • Pneumonia, Viral / prevention & control*
  • Pneumonia, Viral / transmission
  • Pneumonia, Viral / virology
  • Risk Assessment
  • SARS-CoV-2
  • Treatment Outcome
  • Virulence


  • Antiviral Agents
  • Hydroxychloroquine
  • Chloroquine