The UK’s regulatory agency, the MHRA (Medicines and Healthcare products Regulatory Agency) is allowing a trial of the drug hydroxychloroquine to resume.

Hydroxychloroquine and chloroquine are drugs used for decades to prevent malaria and to treat rheumatoid arthritis and lupus.

In late May, the World Health Organization halted trials using hydroxychloroquine and chloroquine which were intended to see if those drugs could treat COVID-19.  Trials in 6,000 people showed that people taking those drugs had a greater chance of death than those who did not.   On June 8, the MHRA had halted recruitment into hydroxychloroquine trials.

The trial authorized by the MHRA will be a randomized, placebo-controlled trial in up to 40,000 healthcare workers to see if hydroxychloroquine or chloroquine can prevent COVID-19.  Previous trials with these drugs were focused on treating COVID-19.