Scientists Say Chloroquine Might Aid Treatment of Coronavirus Infection
Since the ongoing coronavirus outbreak started in December 2019, researchers have been battling to find a cure. But things look rather bleak at this time because the discovery of an effective cure is not expected to happen this year.
Scientists are now turning to some old drugs to find which would be helpful to patients in the meantime. And they have observed that chloroquine could help for the treatment of the CoVID-19 disease.
The drug, popularly used for malaria and autoimmune disease, is currently being tested for this purpose in 10 Chinese hospitals.
The new coronavirus was first reported in the city of Wuhan in Hubei province at the end of last December. Since then, the outbreak has spread to all of China’s provinces and to other countries as well.
Potent coronavirus inhibitor
Research has shown that chloroquine phosphate is effective against viruses, including coronaviruses.
In a 2005 study published in Virology Journal, scientists noted that the drug exhibited potent antiviral effects against the coronavirus responsible for the severe acute respiratory syndrome (SARS). They found that it inhibited the virus when primate cells were treated with it before or after exposure.
Chloroquine blocked SARS-CoV from spreading in cell culture. It showed potential usefulness for both preventing and treating coronavirus infections.
The antimalarial seems to target angiotensin-converting enzyme 2 (ACE2). Coronavirus, including SARS-CoV-2, is believed to use this to enter cells.
The observed efficacy of chloroquine in the past is currently driving interest in trying it out against the CoVID-19 virus as well. It appears to be getting the most attention of all old drugs currently being investigated as a potential treatment by scientists.
Treating CoVID-19 with chloroquine
Researchers in China are testing the antimalarial drug in over 100 CoVID-19 patients in about 10 hospitals.
According to the scientists, patients that received chloroquine are showing more improvement than those who did not. There was a reduction in fever among those in the treatment groups and a greater proportion recovered quicker, compared to control subjects.
China National Center for Biotechnology disclosed that experts have proposed the use of the drug in wider clinical trials.
In a similar vein, the multicenter collaboration group of the Department of Science and Technology and the Health Commission of Guangdong Province has published an “expert consensus” on the usefulness of chloroquine for the treatment of pneumonia due to the novel coronavirus. It stated that the drug could aid treatment success and reduce the length of hospital stays.
In their paper published in the Chinese journal Yiigle, the researchers recommend the use of a 500mg tablet two times daily for 10 days. This is for patients diagnosed with mild, moderate, or severe cases of pneumonia caused by the virus.
The drug is, however, not recommended for patients with allergy or hypersensitivity issues related to it.
Chloroquine Dosage for Coronavirus: Guidelines From China
Chloroquine phosphate (adult 18 to 65 years old weighing more than 50 kg: 500 mg twice daily for 7 days; bodyweight less than 50 kg: 500 mg twice daily for day 1 and 2, 500 mg once daily for day 3 through 7)
How about quinine?
Chloroquine is a synthetic version of quinine, another old malaria drug that is a lot less popular these days. Prior to the end of World War II, the latter was the preferred drug for malaria despite its side effects.
Due to this similarity, some people think tonic water products, such as Schweppes and Canada Dry, might be beneficial against SARS-CoV-2. These beverages contain dissolved quinine, which explains their somewhat bitter taste.
However, there is currently no evidence that tonic water, or quinine, could inhibit the novel coronavirus. This may be because scientists have focused more on chloroquine in their studies.
In fact, the most popular hypothesis of how the natural compound fights malaria parasites takes much from what researchers have observed when studying chloroquine.
Existing drugs currently being investigated for the treatment of the CoVID-19 disease include remdesivir, initially made for Ebola virus treatment. Among the others are azvudine and a cocktail of ritonavir and lopinavir.
[Expert consensus on chloroquine phosphate for the treatment of novel coronavirus pneumonia]. – PubMed – NCBI (https://www.ncbi.nlm.nih.gov/m/pubmed/32075365/)
(PDF) Chloroquine is a potent inhibitor of SARS coronavirus infection and spread (https://www.researchgate.net/publication/7646092_Chloroquine_is_a_potent_inhibitor_of_SARS_coronavirus_infection_and_spread)
Old malaria drugs could be used to treat coronavirus | Metro (https://metro.co.uk/2020/02/27/old-malaria-drugs-used-treat-coronavirus-12314390/)
Coronavirus puts drug repurposing on the fast track – Nature (https://www.nature.com/articles/d41587-020-00003-1)
Quinine – Wikipedia (https://en.wikipedia.org/wiki/Quinine)