Authors: Heather Jones, Future Science Group
A comprehensive clinical review, published in the FASEB Journal, has casted doubt on the use of chloroquine (CQ) and hydroxychloroquine (HCQ) for COVID-19, despite recent anecdotal reports suggesting that these malaria drugs might be effective against SARS-CoV-2. The authors emphasize the need for caution and further clinical research into the efficacy and safety of these drugs.
Chloroquine and hydroxychloroquine have been previously touted as a “magic bullet” to prevent and cure COVID-19, after small-scale preliminary trials yielded some encouraging results. However, not all results have been either conclusive or positive.
“When I went on service a few weeks ago in the ICUs of Massachusetts General Hospital as an infectious diseases attending physician, it was evident to me and my colleagues that there were both risks and benefits of the widespread initial use of hydroxychloroquine in the context of COVID-19 infection. This was based on seeing patients who, for whatever reason, appeared to be doing poorly despite the use of this medication,” explained Mark Poznansky, lead author of the review (Harvard Medical School and Massachusetts General Hospital, MA. USA).
The research team aimed to investigate aspects of the anti-viral and immune modulatory activities of hydroxychloroquine that could potentially aid or impair a patient’s response to the virus, in order to help physicians make informed decisions about using this drug within carefully designed clinical trials.
Upon reviewing the early anecdotal reports and clinical trials responsible for the considerable optimism and widespread adoption of this therapy, the authors noted that although these drugs have been demonstrated to reduce viral uptake by cells cultured in the laboratory, this has not yet been confirmed in patients.
Even more concerning was the immunosuppressive action of these drugs, which caused them to fail in previous respiratory virus outbreaks, including influenza. The authors postulate that hydroxychloroquine and chloroquine inhibit innate immune reactions and the generation of adaptive, cell-mediated immunity, both of which are critical for viral defense.
Meanwhile, amid reports of deaths in some parts of the world due to inappropriate self-use of chloroquine, pharmacists from the University of Huddersfield have noted in an article published in the British Journal of Pharmacy that “there is no evidence to support the mass use of CQ/HCQ to prevent the infection in public at large, therefore these drugs cannot be recommended for general use by the public to protect from acquiring SARS-CoV-2 infection.”
They also put forward the need for an open-access central repository for clinicians to record the use and outcomes of CQ/HCQ.
Concluding their research, the authors of the FASEB review emphasize the evident need for caution in using these drugs based solely on lab-based data, as clinical trial results continue to lower opinions on their utility for COVID-19.
Sources: Meyerowitz EA, Vannier AGL, Friesen MGN et al. Rethinking the role of hydroxychloroquine in the treatment of COVID‐19. FASEB J. doi: 10.1096/fj.202000919 (2020); Hasan SS, Kow CS, Merchant HA. Is it worth the wait? Should Chloroquine or Hydroxychloroquine be allowed for immediate use in COVID-19? Br. J. Pharm. 5(1) (2020); www.eurekalert.org/pub_releases/2020-04/foas-ncr042820.php; www.hud.ac.uk/news/2020/april/chloroquine-hydroxychloroquine-cures-for-covid-19/