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A nurse stands outside a drive-up coronavirus testing station at the University of Washington Medical Center. (AP Photo/Ted S. Warren) A nurse stands outside a drive-up coronavirus testing station at the University of Washington Medical Center. (AP Photo/Ted S. Warren)

A nurse stands outside a drive-up coronavirus testing station at the University of Washington Medical Center. (AP Photo/Ted S. Warren)

Jon Greenberg
By Jon Greenberg April 7, 2020

If Your Time is short

  • President Trump and many others believe this drug has great promise for treating COVID-19. His health advisers urge against putting too much hope in the drug, which is used to treat conditions such as malaria and lupus.

  • The jury is still out on its effect, with over 50 studies in the works.

  • Two early studies found that it helped people clear the virus quickly.

  • Two other studies found that it made no difference.

For President Donald Trump and members of his inner circle, hydroxychloroquine stands out as a bright point of hope in the fight against the coronavirus. His personal lawyer Rudy Giulinani has been touting it as a key weapon in the public health arsenal. So has Fox News host Laura Ingraham, who pitched the drug to Trump at a White House meeting.

The medical community warns that while hydroxychloroquine and its chemical cousin chloroquine have been used for a long time, neither has been proven effective against COVID-19.

Doctors use hydroxychloroquine to treat lupus and rheumatoid arthritis. Chloroquine is used to treat malaria, according to the Centers for Disease Control and Prevention.

Hydroxychloroquine is more widely available in the United States, and the hopes for it rest on a pair of preliminary studies. While those are getting a lot of attention, there are other early studies that say the drug makes no difference at all.

The big picture is that it is too early to tell. Here’s what we know so far.

Two studies from China reach opposite conclusions

Promising study: A group of doctors at Renmin Hospital of Wuhan University, the city that became ground zero for COVID-19 at the end of last year, randomly divided 62 patients into two groups. One received 400 milligrams of hydroxychloroquine for five days, and the other group did not.

After five days, the body temperature and cough went down faster in the treatment group. The authors gave no details on the initial severity of the disease in each group. 

The doctors wrote "the use of (hydroxychloroquine) could significantly shorten time to clinical recovery and promote the absorption of pneumonia."

Study showing no difference: A separate group of doctors at Fudan University in Shanghai also used a 400 milligram daily dose. They randomly assigned 30 patients to two groups — a test group and a conventional treatment group.

After seven days, they checked the level of the virus in everyone. The virus essentially disappeared in 87% of the test group. But it also went away for 93% in the control group. 

In short, the hydroxychloroquine had no discernible benefit.

Two studies from France reach opposite conclusions

Promising study: In a hospital study out of Marseilles, France, 80 people with COVID-19 were given a combination of hydroxychloroquine and another drug azithromycin. The hydroxychloroquine dose was a bit higher than in the Chinese studies, 600 milligrams a day for 10 days, plus an initial dose of 500 milligrams of azithromycin, followed by 250 milligrams for four days.

By the fifth day, over 95% of the patients tested negative for the virus. 

"We confirm the efficacy," and the "potential effectiveness in the early impairment of contagiousness," the researchers wrote March 12.

But there are issues with this study. There was no control group, so there is no comparison with patients, who, except for getting the drug treatment, were basically the same as the test group.

Also, only 15% of the patients had fevers, a key sign of how hard the disease is hitting a person’s body. This suggests "these patients likely would have naturally cleared the virus without any intervention," wrote University of Maryland biochemist Katherine Seley-Radtke in The Conversation

The journal where the study first appeared said April 3 that the article fell short of the group’s "expected standard." It specifically noted lapses in the selection of participating patients.

Study showing no difference: Doctors at a hospital in Paris used the same treatment as the Marseilles study on 10 patients and found no marked improvement. Testing showed 80% of the patients still had the virus six days after treatment began.

The results "cast doubts about the strong antiviral efficacy of this combination," the authors wrote March 30.

Ongoing studies

To date, all the public has now are conflicting studies. Many researchers say that the country will need to wait for hard information to determine whether hydroxychloroquine has an effect. 

The FDA has approved emergency use, and the National Institutes of Health lists over 50 studies underway worldwide. Some test the drug in combination with other drugs, some focus on people with mild symptoms, and some on more serious cases. Collectively, they cover a range of situations and approaches.

RELATED: Why medical experts worry about Trump touting chloroquine

Doctors are cautious with the drug because it can cause heart damage, throwing off the heartbeat or reducing blood flow. In the Marseilles study, doctors stopped the trial for several patients when they spotted signs of distress.

There are two main tracks to see what hydroxychloroquine, either alone or mixed with other drugs, can do. There are efforts to see if it helps treat the disease. The World Health Organization has a multinational project on that front.

Then there is prevention. The Gates Foundation is spearheading a two-month study in the United States to see if hydroxychloroquine can stop health care providers who are exposed to the virus daily from getting COVID-19.

This article was updated shortly after publication to include a link to the original journal saying the article about the Marseilles study fell short of its standards.

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Our Sources

MedRxIV, Efficacy of hydroxychloroquine in patients with COVID-19: results of a randomized clinical trial, March 31, 2020

U.S. Food and Drug Administration, Fact sheet for health care providers emergency use authorization (EUA) of hydroxychloroquine sulfate, April 3, 2020

Médecine et Maladies Infectieuses, No Evidence of Rapid Antiviral Clearance or Clinical Benefit with the Combination of Hydroxychloroquine and Azithromycin in Patients with Severe COVID-19 Infection, March 30, 2020

Journal of ZheJiang University, A pilot study of hydroxychloroquine in treatment of patients with common coronavirus disease-19, March 6, 2020

Méditerranée Infection, Clinical and microbiological effect of a combination of hydroxychloroquine and azithromycin in 80 COVID-19 patients with at least a six-day follow up: an observational study, March 12, 2020

The Conversation, A small trial finds that hydroxychloroquine is not effective for treating coronavirus, April 3, 2020

University of Washington, Study to ask: Does antimalarial drug prevent COVID-19?, March 30, 2020, March 30, 2020

Gates Foundation, Three Weeks, Two Drug Trials, accessed April 6, 2020

UN News, UN health chief announces global ‘solidarity trial’ to jumpstart search for COVID-19 treatment, March 18, 2020

CDC, Information for Clinicians on Therapeutic Options for COVID-19 Patients, March 21, 2020

Annals of Internal Medicine, Use of Hydroxychloroquine and Chloroquine During the COVID-19 Pandemic: What Every Clinician Should Know, March 31, 2020

Yale Medicine, Can Hydroxychloroquine Treat COVID-19? We Don’t Know Yet, April 1, 2020

U.S. Food and Drug Administration, Emergency Use Authorization, accessed April 2, 2020

National Institutes of Health, Clinical studies: COVID-19 and hydroxychloroquine, accessed April 7, 2020

International Society of Antimicrobial Chemotherapy, Statement on IJAA paper, April 3, 2020

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