Review: Chloroquine, Hydroxychloroquine Likely Ineffective For COVID-19

Chloroquine and hydroxychloroquine likely are not effective against the novel coronavirus, according to a paper published in the May issue of The FASEB Journal. The journal is published by the Federation of the American Societies for Experimental Biology (FASEB), which has 28 societies and more than 130,000 members.

Investigators from Harvard Medical School and Massachusetts General Hospital conducted a comprehensive literature review of clinical experiences with chloroquine and hydroxychloroquine in order to determine these drugs’ potential safety and efficacy in fighting COVID-19. They also reviewed anecdotal reports and poorly controlled clinical trials that raised the initial optimism about these therapeutic treatments.

Chloroquine and hydroxychloroquine are effective against malaria, rheumatoid arthritis, and lupus, but likely not COVID-19, investigators wrote.

The lead study author, Mark Poznansky, MD, PhD, said he worked in the intensive care unit at Massachusetts General as an infectious disease attending physician and noticed that there were both risks and benefits to treating COVID-19 with hydroxychloroquine. He saw patients who appeared to be doing poorly when given the drug, he said. Because of this, he wanted to “create a science-based awareness of this subject,” he explained in a statement.

“Beyond the known cardiac side effects of this drug, we aimed to reveal those aspects of the anti-viral and immune modulatory activities of hydroxychloroquine that could potentially help or, as importantly, impair a patient’s response to the virus,” he said. “The goal was to help physicians make data-informed decisions about how to use this drug for patients with COVID-19 infection within carefully designed clinical trials.”

The analysis resulted in significant skepticism for hydroxychloroquine or chloroquine therapy for COVID-19 treatment. Specifically, data through April 22 showed that these drugs reduced viral uptake by cells cultured in a lab rather than in patients.

Additionally, investigators noted, the immunosuppressive action of the drugs is also troublesome. While effective for the purposes of rheumatoid arthritis and lupus, they have failed in treating other respiratory outbreaks such as influenza.

The drugs prevent the immune system from completing its vital response to viruses, investigators wrote. The drugs also disrupt the cell-mediated immunity that is critical to controlling a viral outbreak such as the one the world is currently facing.

There is a need for cautioning against using these therapies to treat the coronavirus based solely on the results of lab studies and not human trials. The team wrote that the current trial results involving chloroquine and hydroxychloroquine are “leading to a rapidly diminishing view of their utility for COVID-19.”

More doubt for the use of chloroquine and hydroxychloroquine to treat the coronavirus came from a research letter published in JAMA Internal Medicine, showing a spike in online searches to purchase the drugs from online retailers after the drugs were touted by high-profile public figures including President Trump and Elon Musk.