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U.S. President Donald Trump said he was taking hydroxychloroquine to ward off Covid-19
Tests of hydroxychloroquine, a malaria drug, as a possible treatment for coronavirus, have been halted due to safety concerns, says the World Health Organization (WHO).
Tests in several countries are being "temporarily" suspended as a precaution, the agency reported on Monday.
This is after a recent medical study suggested that the drug could increase the risk of patients dying from Covid-19.
President Donald Trump said he is taking the drug to ward off the virus.
The US president has repeatedly promoted the antimalarial drug, against medical advice and despite warnings from public health officials that it could cause heart problems.
Last week, a study published in the medical journal The Lancet said there was no benefit in treating patients with coronavirus with hydroxychloroquine, and that ingestion may even increase the number of deaths among those hospitalized with the disease.
Hydroxychloroquine is safe for malaria and conditions like lupus or arthritis, but no clinical trial has recommended its use in the treatment of Covid-19.
Researchers say Covid-19 patients should not use hydroxychloroquine outside clinical trials
The WHO, which is conducting clinical trials of various drugs to assess which may be beneficial in treating the disease, had previously raised concerns about reports of individuals who self-medicate and cause serious harm.
On Monday, UN health agency officials said the hydroxychloroquine would be removed from the tests, pending a safety assessment.
The Lancet study involved 96,000 patients with coronavirus, almost 15,000 of whom received hydroxychloroquine – or a related chloroquine form – alone or with an antibiotic.
The study found that patients were more likely to die in the hospital and develop heart rhythm complications than other Covid patients in a comparison group.
The mortality rates of the treated groups were: hydroxychloroquine 18%; chloroquine 16.4%; control group 9%. Those treated with hydroxychloroquine or chloroquine in combination with antibiotics had an even higher mortality rate.
The researchers cautioned that hydroxychloroquine should not be used outside of clinical trials.