On March 19, 2020, during the White House press briefing on coronavirus Covid-19
in the United States, US President Donald Trump surprised some observers in the
medical sciences world when he revealed the US Food and Drugs Administration
had approved the use of chloroquine and hydroxychloroquine for the treatment of
the coronavirus in patients.
This wasn’t totally accurate, but the FDA had indeed
approved coronavirus patient trials of the drugs, which are best known for the
treatment of malaria and arthritis. The decision came after early studies
showed that chloroquine and Hydroxychloroquine are effective in inhibiting the
disease when tested in vitro with primate cells.
During the conference FDA commissioner, Dr Stephen Hahn said
the regulator is preparing to test the drug in a clinical trial with
coronavirus patients. There are already clinical trials in China and more
scheduled to start in several other countries.
SARS and Covid-19 virus infect humans when protein spikes on
its surface bind to special receptors on the surface of human cells.
Chloroquine worked against SARS by interfering with those receptors, thereby
reducing the virus’s ability to bind to cells. Researchers believe there is a
chance Chloroquine can do the same against Covid-19. However, Dr Hahn pointed
out some concerns about the drug as a possible treatment for the virus. “We may
have the right drug, but it might not be in the appropriate dosage form right
now, and it might do more harm than good”, he warned.
But the cat was out of the proverbial bag. Earlier this
week, Google Trends identified “chloroquine” as the second most searched
coronavirus-related term in the US.
Mentions of Chloroquine had also been trending on Twitter in
Nigeria and Ghana. Why? Africa accounts for 92% of malaria cases in the world
and chloroquine-based drugs are very familiar medications on the continent. As
soon as rumors started circulating of a possible Covid-19 “cure” with
chloroquine it went viral on Nigerian social media and many Nigerians have
reportedly started to stock the drug. And after Trump’s comments it has led to
a rapid increase in the price of the drug and pharmacies running out of stock.
A child is given an injection as part of a malaria vaccine
trial at a clinic in the Kenya
But there’s also a down side to a medication which many
Africans have sometimes used reluctantly because of its side effects. Some have
been sharing their “Chloroquine experience” on social media. The most
talked-about experience other than its very bitter taste, is the “pruritus and
paresthesia” it causes. These are stinging, burning or prickling sensations
which worsen with age and can last for hours or even days as the most common
side effects.
Origin story
Chloroquine was discovered in 1934 at the Bayer
Laboratories, who named it Resochin. It was ignored for a decade because it was
considered too toxic for human use. During World War II, US
government-sponsored clinical trials for antimalarial drug development showed
unequivocally that chloroquine has a significant therapeutic value as an
antimalarial drug.
It was introduced into clinical practice in 1947 for the
preventive treatment of malaria. The disease is caused by the protozoan
parasite Plasmodium, which often grows in the liver before infecting red blood
cells. With malaria Chloroquine works by interfering with the growth of the parasite
in the cells.
However, the use of chloroquine for treating malaria has
dropped over the years and other malaria drugs are mostly used today. Many
doctors stopped using chloroquine because more and more patients complained of
side effects even as the resistance of the malaria parasite towards it
increased, says Dr Chimaobi Nwokeocha, a medical doctor at a private hospital
in Nasarawa, northern Nigeria. But even then the doctor acknowledges
chloroquine is still widely used.
Some of the side effects also include chloroquine
retinopathy (damage to the retina) and insomnia but of even more concern is
that the drug can also be deadly if abused. In Nigeria, due to a lack of
enforced regulation, it is fairly easy to get prescription medicine over the counter
at local pharmacies. After Trump’s announcement, there have already been two
cases of chloroquine poisoning reported in Lagos. “It is not advisable for
anyone to buy chloroquine over the counter without a doctor’s prescription,”
says Dr Nwokeocha.
Hydroxychloroquine, the less toxic derivative of Chloroquine
appears to be the drug of choice for large-scale use compared to other drugs
with similar capacity, due to its availability, proven safety record and a
relatively low cost.
There has been much talk and concern over Africa’s “fragile
health systems” as the coronavirus
spread picks up speed across the continent where it is now in more than 30
countries with over 800 cases. That’s why if chloroquine is proven to indeed be
an effective Covid-19 treatment many Africans will be relieved as a familiar
and accessible drug might just be able
help prevent a catastrophe on the continent.
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