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There is currently not enough evidence from clinical trials of chloroquine and hydroxychloroquine to determine whether the drugs are safe and effective treatments for COVID-19, finds research from Oxford University researchers.

In their rapid review of clinical trial data for BJGP Open, Dr Kome Gbinigie and Dr Kerstin Frie, from the Nuffield Department of Primary Care Health Sciences, say that larger, randomised clinical trials are urgently needed in both community and hospital settings. These studies would ideally “blind” participants to the treatment they are taking and present medium to long-term follow-up data. Such studies would guide policy-makers and clinicians to make decisions for patients based on high-quality evidence.

Since WHO declared that COVID-19 was a pandemic on 11th March 2020, there has been growing interest in the use of existing medicines as potential treatments, such as chloroquine and hydroxychloroquine.

Both drugs have been incorporated into some national guidelines to treat COVID-19 in certain situations, despite the lack of rigorous clinical trial data.

The two researchers analysed the findings of a study of 30 COVID-19 patients in China, published on 6th March 2020, and a second trial of 36 COVID-19 patients in France, published on 17th March 2020.

Commenting, Dr Kome Gbinigie, a DPhil student and part-time GP, said “Data from two clinical trials reveal conflicting results about the effectiveness of hydroxychloroquine. Both studies had small numbers of participants, provided no medium or long-term follow-up with patients and had methodological limitations.

“Fortunately, more than 20 clinical trials of chloroquine and hydroxycholoquine are already registered, which should help to inform whether these drugs are effective, as well as the optimal dose and the duration that is necessary to treat COVID-19.”

The researchers are both funded by the Wellcome Trust.

Read more:

Should Chloroquine and Hydroxychloroquine be used to treat COVID-19? A rapid review.
Kome Gbinigie, Kerstin Frie, BJGP Open 8 April 2020. DOI:




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