FDA on Friday warned providers not to use the anti-malaria drugs chloroquine and hydroxychloroquine to treat Covid-19 patients outside of a clinical trial or hospital setting because the drugs could cause patients to experience "serious heart rhythm problems."

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US Covid-19 cases surpass 965K, death toll tops 49K

The warning came as the number of reported cases of Covid-19, the disease caused by the new coronavirus, continued to rise. As of Monday morning, U.S. officials had reported 965,214 cases of Covid-19 in the country—up from 867,105 cases as of Friday morning.

Officials as of Monday morning also had reported 49,465 U.S. deaths linked to the new coronavirus—up from 44,464 deaths reported as of Friday morning.

FDA issues warning regarding chloroquine and hydroxychloroquine for Covid-19 patients

Both chloroquine and hydroxychloroquine are FDA-approved to treat or prevent malaria. Hydroxychloroquine also has been used to treat lupus and rheumatoid arthritis. President Trump has been a vocal supporter of using hydroxychloroquine as a potential treatment for Covid-19, but the drug hasn't been proven to successfully treat Covid-19 in any large clinical trials. Further, providers and researchers have expressed concerns about touting the drug as a potential treatment for Covid-19 because patients with heart problems and other underlying medical conditions have a high risk of experiencing negative side effects from hydroxychloroquine.

FDA previously issued emergency use authorizations giving providers permission to use hydroxychloroquine and chloroquine phosphate "supplied from the Strategic National Stockpile" to treat the disease outside of a clinical trial.

Now, FDA in a drug safety communication issued Friday clarified that its emergency use authorizations allow providers to treat Covid-19 patients with chloroquine and hydroxychloroquine only if they are closely monitoring the patients as part of a clinical trial or in hospital settings, and the agency advised providers not to treat Covid-19 patients with the drugs outside of those settings.

FDA warned providers that Covid-19 patients could experience life-threatening side effects when taking chloroquine and hydroxychloroquine. FDA said the side effects have included "abnormal heart rhythms such as QT interval prolongation, dangerously rapid heart rate called ventricular tachycardia and ventricular fibrillation, and in some cases, death."

FDA said many of the reported adverse reactions involved Covid-19 patients who received a combination of malaria drugs and the antibiotic azithromycin, which is commonly called Z-Pak.

"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," FDA Commissioner Stephen Hahn said in a statement. "We encourage health care professionals making individual patient decisions to closely screen and monitor those patients to help mitigate these risks."

FDA's warning came after a study released last week that involved 368 Veterans Affairs patients showed hydroxychloroquine, when used with or without azithromycin, did not help prevent hospitalized Covid-19 patients from needing ventilators. The study also suggested that hydroxychloroquine alone was linked to an increased risk of death among patients involved in the study. The study has not yet been peer reviewed, and it was not based on a controlled trial.

Similarly, researchers in a study published Friday in JAMA noted that they had to end a study testing chloroquine as a Covid-19 treatment because they found the drug was associated with a high risk of death and toxic effects among the patients involved in the study. The study had included 81 patients who were hospitalized with severe cases of Covid-19.

CDC identifies six new Covid-19 symptoms

As public health officials and researchers continue to seek a treatment for Covid-19, CDC has updated its website to reflect six new symptoms associated with the disease.

According to USA Today, CDC's website previously listed cough, fever, and shortness of breath as symptoms commonly associated with Covid-19. However, in addition to those symptoms, CDC's website now also lists chills, headaches, loss of taste or smell, muscle pain, sore throat, and repeated shaking with chills as symptoms of Covid-19.

CDC notes that the symptoms may appear within two to 14 days after individuals are exposed to the new coronavirus, and encourages people to consult a medical provider if they develop symptoms that "are severe or concerning."

According to USA Today, CDC's inclusion of new symptoms for Covid-19 "is significant" because "[m]ost testing sites require a patient to have a Covid-19 symptom before the individual can be tested" for the new coronavirus.

CMS no longer accepting applications for advanced Medicare payments

Separately, CMS on Sunday announced that is immediately suspending advanced payments to Medicare Part B suppliers and reevaluating all other pending applications for advanced payments under its Accelerated Payment Program (AAP).

In March, CMS expanded the APP to ensure providers and suppliers have the cash flows needed to address the country's Covid-19 epidemic. CMS said since APP's expansion the agency has made $59.6 billion in advanced payments to Medicare Part A providers, which include hospitals, and $40.4 billion in advanced payments to Medicare Part B providers, which include durable medical equipment suppliers, non-physician practitioners, and physicians.

CMS on Sunday noted that the agency also is doling out a total of $175 billion to hospitals and other providers under two economic stimulus packages that federal policymakers have enacted over the past month. In light of that funding—and the payments CMS already has made under APP—the agency said it would "not be accepting any new applications for [APP], and CMS will be reevaluating all pending and new applications for accelerated payments." The agency said providers instead should seek direct payments through the Provider Relief Fund created under the stimulus packages  (McGinley et al., Washington Post, 4/24; Reuters, 4/24; Grady, New York Times, 4/24; Lovelace, CNBC, 4/24; Grover, Associated Press, 4/24; Miller, USA Today, 4/26; Cohrs, Modern Healthcare, 4/26; CMS release, 4/26; New York Times, 4/27; CDC website, accessed 4/27).