By Mike Curley

Law360 (April 24, 2020, 4:31 PM EDT ) The U.S. Food and Drug Administration issued a warning Friday telling patients and caregivers that malaria drugs touted by President Donald Trump as a "game changer" in treating COVID-19 have been reported to have serious and life-threatening side effects when used to treat the disease.

Hydroxychloroquine and chloroquine have been reported as causing life-threatening heart rhythm problems, the FDA said in the warning. The drugs are currently undergoing clinical trials studying their effects on the virus, but as yet have not been approved for use by the FDA, the agency said in a release.

The drugs are currently being used as a treatment in limited circumstances under an emergency use authorization for adolescent and adult patients, according to the FDA, which said the EUA requires that fact sheets with information about the drugs, including side effects, be provided to health care providers and patients.

"We understand that health care professionals are looking for every possible treatment option for their patients and we want to ensure we're providing them with the appropriate information needed for them to make the best medical decisions," FDA Commissioner Stephen M. Hahn said in a press release Friday. "While clinical trials are ongoing to determine the safety and effectiveness of these drugs for COVID-19, there are known side effects of these medications that should be considered. We encourage health care professionals making individual patient decisions closely screen and monitor those patients to help mitigate these risks."

According to the FDA's warning, the risk of side effects may increase when the drugs are combined with other drugs currently being used to treat COVID-19, such as the antibiotic azithromycin.

Patients with other health issues, such as heart and kidney disease, are likely to be at increased risk of heart problems when taking hydroxychloroquine and chloroquine, the FDA added.

The drugs have been the center of debate after Trump touted them as a "game changer" in the fight against COVID-19. In recent weeks, however, researchers have reported that patients treated with the drugs have died at a higher rate than those receiving regular treatment.

A White House spokesperson said Friday, "From the beginning, Democrats and the media have mounted a coordinated effort to criticize this President for discussing a proven, safe drug throughout this pandemic as a possible treatment that could save a person's life. While some are rooting for the drug to fail, President Trump is simply offering a consistent message of hope, comfort, and optimism while telling Americans to consult with their doctor."

In the FDA's warning Friday, the agency stated that hydroxychloroquine and chloroquine have not been proved safe and effective in treating COVID-19.

The FDA further advised that the drugs should only be taken with supervision by medical professionals and patients should not buy them from online pharmacies without a prescription. The risks can be mitigated by close screening and supervision by medical professionals of patients in a hospital setting or clinical trial, the FDA said.

The agency added it plans to continue investigating risks associated with the use of the drugs in treating COVID-19 and will publish additional information as it becomes available.

Earlier this week, Dr. Rick Bright, formerly the director of the U.S. Department of Health and Human Services' Biomedical Advanced Research and Development Authority, said he was removed from that position after pushing for "safe and scientifically vetted solutions" rather than unproven drugs touted by Trump's administration.

Bright has said he intends to file a whistleblower complaint requesting that the HHS inspector general look into the Trump administration's politicizing of the research and development authority's work.

--Editing by Abbie Sarfo.

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