As the coronavirus continues to infect hundreds of thousands of people each day, many scientists and health professionals have become more desperate to find and create a vaccine. Many of them are investigating several potential coronavirus therapies, hoping they could find the solution to stop this pandemic. One of the drugs they are looking into is hydroxychloroquine, an anti-malaria drug.
Hydroxychloroquine is not only used to prevent or treat malaria but also to treat certain auto-immune diseases such as lupus and rheumatoid arthritis. It’s believed that this drug affects how a person’s immune system works. In recent months, it has gained worldwide attention as US Pres. Donald Trump called it a potential “game-changer.” He revealed that he had taken the drug for several days as a way to protect against COVID-19 infection. Pres. Trump announced this despite the lack of evidence that it works for this purpose.
However, many scientists have shown alarming evidence that hydroxychloroquine may not be beneficial after all.
Why Do Researchers Think That Hydroxychloroquine May Prevent COVID-19 Infection?
Hydroxychloroquine is a well-known antiviral against many viruses, including SARS and MERS. Last March, a small study in France suggested that it might be effective in reducing some of the symptoms of COVID-19. In lab tests, the drug was proven to have stopped the virus from infecting cells and decreased the replication of viruses that get inside cells. According to Time, an American weekly news magazine and news website, previous studies in animals and cell cultures in the lab show it may also help in suppressing the aggressive immune reaction that doctors have seen in some patients’ lungs and respiratory systems.
The drug was also thought to block viruses from entering cells by changing the pH, or acidity, of cellular compartments, called lysosomes. Michael Avidan, an anesthesiologist at Washington University School of Medicine in St. Louis, said that this “creates a less friendly environment for the virus, so it might be more difficult for the virus to get into human cells in the first place.” Also, researchers from a report published in Nature last April 30 showed that hydroxychloroquine can disrupt interactions between some of SARS-CoV-2’s proteins.
Co-author Adolfo Garcia-Sastre, a microbiologist who directs the Global Health and Emerging Pathogens Institute of Icahn School of Medicine at Mount Sinai in New York City, explained that interrupting those protein interactions may make it difficult for the virus to replicate. Another reason why this drug has been extremely attractive for scientists searching for the COVID-19 vaccine is that it is widely available.
For decades, doctors have been prescribing hydroxychloroquine—approved by the US Food and Drug Administration. While it has some serious side effects, it’s been generally safe to use. “Time is of the essence. When you have a drug that you understand and can safely administer that’s on the shelf, that’s the drug you reach for first,” Adam Spivak, an infectious-disease doctor at the University of Utah in Salt Lake City, said.
Why Hydroxychloroquine is Not Safe to Use
Since Pres. Trump shared how hydroxychloroquine seemingly helped him in preventing to not be infected by COVID-19, many scientists conducted tests to prove whether this is true or not. However, the findings were not very promising.
A recent study published in the New England Journal of Medicine reported that hydroxychloroquine did not seem to protect people at high risk of infection from getting COVID-19. More significantly, the researchers noted that hydroxychloroquine administration was associated with an increased risk of cardiac events and death. As a result, the World Health Organization announced it was suspending the use of this drug in human trials.
According to Live Science, a science news website that features groundbreaking developments in science, space, technology, health, the environment, our culture, and history, the study involved 821 people who were exposed to a person with COVID-19. They were randomly assigned to receive hydroxychloroquine or a placebo within four days of their exposure. The findings revealed that about 12% of participants in the hydroxychloroquine group and 14% of participants in the placebo group developed symptoms of COVID-19 after two weeks.
It was also reported that 40% of people in the hydroxychloroquine group experienced side effects, including nausea, upset stomach, and diarrhea, compared to only 16% in the placebo group. “We found that hydroxychloroquine was no better than placebo in preventing COVID-19 infection after people have already been exposed to it,” co-author Dr. Emily McDonald, assistant professor of medicine at McGill University, said.
Thus, Dr. Radha Rajasingham, assistant professor of medicine at the University of Minnesota and another co-author of the study, suggested not to use hydroxychloroquine as post-exposure prophylaxis for COVID-19. Another study conducted by UK researchers revealed findings that are persuading several doctors to stop using the drug for COVID-19.
According to Science Mag, an online site that features daily news articles, feature stories, reviews, and more in all disciplines of science, 25.7% of 1,542 hospitalized patients treated with hydroxychloroquine had died after 28 days, compared with 23.5% in a group of 3132 patients who had only received standard care. The authors said that the data convincingly ruled out any meaningful mortality benefit.
“The Recovery trial, in addition to the signals from other studies we have received so far, is enough to convince me to not offer hydroxychloroquine to hospitalized patients,” Nahid Bhadelia, a physician at Boston Medical Center, said.
Several other studies have also raised flags with hydroxychloroquine, linking the use of the drug in COVID-19 patients with prolonged QT intervals. This can cause an irregular heartbeat and increase the risk of sudden cardiac arrest. In fact, a randomized trial of COVID-19 patients in Brazil was stopped after researchers found a high dose of hydroxychloroquine was associated with higher mortality and excessive QT prolongation compared with a low dose of the drug.
A meta-analysis of 24 such studies published in the Annals of Internal Medicine, thus, concluded there was “insufficient and often conflicting evidence on the benefits and harms of using hydroxychloroquine or chloroquine to treat COVID-19.” Last April, the US Food and Drug Administration issued a warning about using the drug outside of study settings. The warning also advised doctors not to prescribe the drug off-label for treating COVID-19.