Chloroquine for COVID-19? Despite presidential promises, the science remains unclear

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On Thursday, President Donald Trump announced that the antimalarial drug chloroquine had shown “very encouraging early results” in treating COVID-19, and falsely claimed:

“…[W]e’re going to be able to make that drug available almost immediately. And that’s where the FDA has been so great. They — they’ve gone through the approval process; it’s been approved. And they did it — they took it down from many, many months to immediate.”

The FDA promptly released a statement explaining that no drug has yet been approved to treat or cure COVID-19, although they are in the earliest phases of researching the potential applications of chloroquine, among other known drugs: 

 “It is unacceptable that anyone would take advantage of Americans during this public health crisis, and the FDA wants to make sure everyone knows what legitimate products are being developed.”

We asked our in-house scientist and cannabis expert Marcella McClure, a molecular virologist, to give us her take in the news. 

By Marcella McClure

Chloroquine is approved for human use to combat malaria and it works. We know it is safe in humans at prescribed doses. But there are no results from large scale, clinical trials using chloroquine to treat COVID-19. There are ongoing trials in several countries such as China, England, France and the USA. But keep in mind, you have to get volunteer patients at various stages first, get the control patients who won’t get the drug, and all that jazz. The French and the Chinese are a couple of weeks ahead, and the U.S. is way behind in testing. So the clinical trials are at least six weeks away at perfect best, but it could be months. And there’s always the possibility people may start to get the treatment here if the trials are successful in other countries.

Small studies indicate that chloroquine and various variants help fight COVID-19. Chinese doctors on the front lines were the first to discover that chloroquine is useful but it should not be self-administered as it can be toxic at the wrong dose. They recommend a 500mg twice daily chloroquine phosphate tablet for those diagnosed with mild, moderate or severe cases of COVID-19.

As reported in the Chinese Clinical Trial Register, a study of 100 COVID-19 patients finds that chloroquine phosphate inhibits the exacerbation of pneumonia and shortens the disease course leading to a negative test.

The results of this small study have just been published in Nature, a top level International journal. In this study, 24 patients with COVID-19 infections were treated with chloroquine.  After six days, only 25 percent remained positive, while 90 percent of those who did not receive the chloroquine were still positive, which is good news. The French government is conducting larger studies now.

Another small French study found that hydroxychloroquine and the antibiotic, azithromycin, given in tandem lessened the infection significantly.

Both Roche and Bayer Pharmaceuticals are providing chloroquine for free to all hospitals requesting it. But whether that includes hospitals in the U.S. is uncertain.

Bottom line: all experts have been saying we’re 18 months away from a vaccine. Trump is making it sound as if we’re closer to a cure. But are we? It really doesn’t look like it.

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Marcella McClure

About Marcella McClure

After a successful career as scientist, Dr. Marcella McClure moved to Salinas to enjoy the weather and the people. She enjoys gardening, hiking on beach dunes and rock crawling.