Study on Chloroquine and Hydroxychloroquine in SARS-Cov-2: Repurposing the old Drugs against Today’s Deadly Disease

Introduction: Chloroquine (CQ) and Hydroxychloroquine (HCQ) has received huge momentum as possible treatment for COVID-19. In India the drug is approved for prophylaxis of asymptomatic health workers treating suspected or confirmed COVID-19 cases, and asymptomatic household contacts of confirmed patients. The U.S. Food and Drug Administration (FDA) has issued Emergency Use Authorization (EUA) of HCQ to treat COVID-19.

Materials and Methods: Here we present the database of trials with these compounds in COVID-19.

Discussion: Early 15 registered clinical trials of CQ and HCQ in COVID -19 positive patients in China, showed that the drugs were superior to the control treatment in inhibiting the exacerbation of pneumonia, improving lung imaging findings, promoting a virus-negative conversion, and shortening the disease course. Some studies had no positive results including a multinational registry analysis of HCQ with or without a macrolide for treatment of COVID-19 published online in Lancet on 22nd May 2020.The study showed that there was decreased in-hospital survival and an increased frequency of ventricular arrhythmias when HCQ was used for treatment of COVID-19.In the light of this publication the WHO temporarily paused the HCQ arm of its ‘Solidarity’ global clinical trial on 26th May 2020 and trials with HCQ /CQ for COVID were also suspended. The Lancet paper was in controversy until finally on June 4th 2020 the article was retracted by authors.

Conclusions: Until we get results of WHO fast track ‘Solidarity’ clinical trial and other randomized clinical trials repurposing these drugs remains questionable.