Chloroquine and hydroxychloroquine in covid-19
TheBMJ in 1925 cautiously endorsed Moellgaard’s gold treatment for tuberculosis,1 although it found his pharmacological reasoning “both interesting and instructive.”2 We should be similarly cautious about proposed treatments for people infected with SARS-CoV-2, the virus that causes covid-19. Many proposals are based on in vitro investigations, studies in experimental animals, or experience with interventions in infections with other viruses, whether similar to SARS-CoV-2 (eg, SARS-CoV-1) or not (HIV). Buy Chloroquine Pills Online
This is all true of chloroquine and hydroxychloroquine, both 4-aminoquinolines, which have been suggest as potential treatments for covid-19. Currently, at least 80 trials of chloroquine, hydroxychloroquine, or both, sometimes in combination with other drugs, are register worldwide.
The possible activity of 4-aminoquinolines in infectious mononucleosis was first proposed in 1960, before its viral cause was know.3 Several unsatisfactory clinical trials followed, some with positive results and some negative. In 1967 the authors of a small but well conducted randomised, double blind, placebo controlled trial of chloroquine concluded that “except for supportive measures, infectious mononucleosis is essentially untreatable.”4
Since then, many studies have shown that 4-aminoquinolines are active in vitro against a range of viruses. Their efficacy is been attribute to different mechanisms. For example, they are weak bases and increase endosomal pH in host intracellular organelles, inhibiting autophagosome-lysosome fusion and inactivating enzymes that viruses require for replication.5 They may also affect glycosylation of angiotensin converting enzyme-2, the receptor that SARS-CoV-2 uses to enter cells.6