Chloroquine was shown in 2004 to be active in vitro against SARS coronavirus but is of unproven efficacy and safety in patients infected with SARS-CoV-2. The drug’s potential benefits and risks for COVID-19 patients, without and with azithromycin, is discussed by Dr. David Juurlink, head of the Division of Clinical Pharmacology and Toxicology at Sunnybrook Health Sciences Centre in Toronto.
From Wall Street Journal article:
Our experience suggests that hydroxychloroquine, with or without a Z-Pak, should be a first-line treatment. Unfortunately, there is already a shortage of hydroxychloroquine. The federal government should immediately contract with generic manufacturers to ramp up production. Any stockpiles should be released.
As a matter of clinical practice, hydroxychloroquine should be given early to patients who test positive, and perhaps if Covid-19 is presumed—in the case of ill household contacts, for instance. It may be especially useful to treat mild cases and young patients, which would significantly decrease viral transmission and, as they say, “flatten the curve.”