Hydroxychloroquine/Chloroquine as Therapeutics for COVID-19: Truth under the Mystery

Int J Biol Sci. 2021 Apr 10;17(6):1538-1546. doi: 10.7150/ijbs.59547. eCollection 2021.


The outbreak of coronavirus disease-19 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has rapidly evolved into a global pandemic. One major challenge in the battle against this deadly disease is to find effective therapy. Due to the availability and proven clinical record of hydroxychloroquine (HCQ) and chloroquine (CQ) in various human diseases, there have been enormous efforts in repurposing these two drugs as therapeutics for COVID-19. To date, substantial amount of work at cellular, animal models and clinical trials have been performed to verify their therapeutic potential against COVID-19. However, neither lab-based studies nor clinical trials have provided consistent and convincing evidence to support the therapeutic value of HCQ/CQ in the treatment of COVID-19. In this mini review we provide a systematic summary on this important topic and aim to reveal some truth covered by the mystery regarding the therapeutic value of HCQ/CQ in COVID-19.

Keywords: COVID-19; CQ; HCQ; SARS-CoV-2; clinical trials; therapy.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Antiviral Agents / therapeutic use*
  • COVID-19 / drug therapy*
  • COVID-19 / virology
  • Chloroquine / therapeutic use*
  • Disease Models, Animal
  • Endocytosis
  • Humans
  • Hydroxychloroquine / therapeutic use*
  • SARS-CoV-2 / isolation & purification


  • Antiviral Agents
  • Hydroxychloroquine
  • Chloroquine