Like a carnival barker selling snake oil, President Donald Trump repeatedly has touted the use of chloroquine (generic only), an antimalarial drug, and hydroxychloroquine (PLAQUENIL), another antimalarial drug that also is approved by the Food and Drug Administration (FDA) to treat lupus erythematosus and rheumatoid arthritis, as “game-changing” treatments for novel coronavirus disease (COVID-19). No scientific evidence exists to back up Trump’s claims; the data on which he based his...
Like a carnival barker selling snake oil, President Donald Trump repeatedly has touted the use of chloroquine (generic only), an antimalarial drug, and hydroxychloroquine (PLAQUENIL), another antimalarial drug that also is approved by the Food and Drug Administration (FDA) to treat lupus erythematosus and rheumatoid arthritis, as “game-changing” treatments for novel coronavirus disease (COVID-19). No scientific evidence exists to back up Trump’s claims; the data on which he based his statements were derived from poorly designed studies and anecdotes.
Trump casually said, “Try it, what do you have to lose?” The answer: Possibly your life.
Doctors have known for years that both chloroquine and hydroxychloroquine have serious — and sometimes fatal — adverse effects. Most troublingly, these drugs can cause QT prolongation, a change in the electrical activity of the heart that can lead to a life-threatening and often fatal abnormal heart rhythm.[1],[2] The risk of QT prolongation is enhanced when these drugs are combined with azithromycin (ZITHROMAX),[3] an antibiotic that likewise has been hyped, with no rigorous evidence, as a treatment for COVID-19.
To make matters worse, there are reports of the coronavirus causing inflammation of the heart muscle.[4] That could make patients even more susceptible to chloroquine and hydroxychloroquine’s adverse cardiac events. Moreover, critically ill patients, including those with respiratory failure, often develop severe blood electrolyte abnormalities that further increase the risk of dangerous abnormal heart rhythms.
On March 28, the FDA bowed to White House pressure and recklessly encouraged the use of chloroquine and hydroxychloroquine to treat COVID-19 by issuing an Emergency Use Authorization for release of these drugs from the Strategic National Stockpile for such use.[5]
Unsurprisingly, initial data from an ongoing early-phase randomized clinical trial in Brazil comparing the use of low-dose versus high-dose chloroquine in subjects with severe coronavirus infections showed that more subjects in the high-dose group died and experienced QT prolongation.[6] Likewise, a preliminary report of a study of 368 COVID-19 patients hospitalized at Veterans Health Administration medical centers found that hydroxychloroquine, with or without azithromycin, failed to reduce the need for mechanical ventilation, whereas hydroxychloroquine use was associated with an increased risk of death.[7]
On April 24, the FDA backpedaled by cautioning against the use of chloroquine and hydroxychloroquine for COVID-19 outside of the hospital or a clinical trial because of the risk of dangerous heart rhythm problems.[8] But the agency should have gone even further by advising against use of these drugs outside of randomized clinical trials.
If these drugs continue to be used widely to treat COVID-19 and are subsequently shown not to work, as is likely, no benefit will have been provided, but many patients undoubtedly will have been harmed.
References
[1] Bayshore Pharmaceuticals. Label: chloroquine. April 2020. https://dailymed.nlm.nih.gov/dailymed/fda/fdaDrugXsl.cfm?setid=4543d87b-6a1a-4e08-9cdd-33b4909c2c21&type=display. Accessed April 27, 2020.
[2] Proficient Rx. Label: hydroxychloroquine (PLAQUENIL). September 2019. https://dailymed.nlm.nih.gov/dailymed/fda/fdaDrugXsl.cfm?setid=8aec894d-5711-4079-b167-240713bf04f2&type=display. Accessed April 27, 2020.
[3] Pfizer Labs. Label: azithromycin (ZITHROMAX). April 2019. https://dailymed.nlm.nih.gov/dailymed/fda/fdaDrugXsl.cfm?setid=db52b91e-79f7-4cc1-9564-f2eee8e31c45&type=display#section-7.3. Accessed April 27, 2020.
[4] Long B, Brady WJ, Koyfman A, Gottlieb M. Cardiovascular complications in COVID-19. Am J Emerg Med. 2020. doi: 10.1016/j.ajem.2020.04.048. [Epub ahead of print]
[5] Food and Drug Administration. FDA news release: Coronavirus (COVID-19) update: Daily roundup. March 30, 2020. https://www.fda.gov/news-events/press-announcements/coronavirus-covid-19-update-daily-roundup-march-30-2020. Accessed April 27, 2020. [See “FDA_Coronavirus Update_ March 30, 2020,”]
[6] Borba MG, Val FF, Sampaio VS, et al. Effect of high vs low doses of chloroquine diphosphate as adjunctive therapy for patients hospitalized with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection: A randomized clinical trial. JAMA Netw Open. 2020;3(4.23):e208857.
[7] Magagnoli J, Narendran S, Pereira F, et al. Outcomes of hydroxychloroquine usage in United States veterans hospitalized with Covid-19. Posted April 23, 2020. MedRxiv. doi: https://doi.org/10.1101/2020.04.16.20065920.
[8] Food and Drug Administration. Hydroxychloroquine or chloroquine for COVID-19: Drug safety communication - FDA cautions against use outside of the hospital setting or a clinical trial due to risk of heart rhythm problems. April 24, 2020. https://www.fda.gov/safety/medical-product-safety-information/hydroxychloroquine-or-chloroquine-covid-19-drug-safety-communication-fda-cautions-against-use. Accessed April 27, 2020.