Coronavirus: EMA cautions over use of chloroquine

The EMA said the safety and efficacy of those medicines for treating coronavirus, officially Covid-19, has still to be been proven, and further warned that unauthorised use of the drugs could leave people with conditions for which the products have been approved for use without "vital medicines".

"It is very important that patients and healthcare professionals only use chloroquine and hydroxychloroquine for their authorised uses or as part of clinical trials or national emergency use programmes for the treatment of Covid-19," the EMA said. "Both chloroquine and hydroxychloroquine can have serious side effects, especially at high doses or when combined with other medicines. They must not be used without a prescription and without supervision by a doctor; prescriptions should not be given outside their authorised uses except in the setting of a clinical trial or nationally agreed protocols."

"Chloroquine and hydroxychloroquine are vital medicines for patients with autoimmune conditions such as lupus. It is important that such patients are still able to obtain them and do not face shortages caused by stockpiling or use outside the authorised indications. In some countries, prescribing of the medicines has been restricted to reduce the risk of shortages," the EMA said.

The EMA's announcement comes at a time when many pharmaceutical companies and medical researchers are looking to determine whether existing drugs, authorised for treating other conditions, can be safely and effectively applied to curb the effects of coronavirus in patients. On Friday, the EMA's human medicines committee, for example, gave recommendations for how antiviral drug remdesivir might be prescribed to Covid-19 hospital patients on compassionate use grounds.

US president Donald Trump last month referred to chloroquine as a medicine that had been approved for the treatment of Covid-19, a claim US medicines regulator the Food and Drugs Administration subsequently had to deny, though the FDA has granted emergency use authorisation for the products.

However, in the US and elsewhere in the world research is being undertaken to determine whether chloroquine and hydroxychloroquine are effective in treating people with Covid-19. This includes clinical trials testing backed by London-based charity the Wellcome Trust. The EMA said that some countries, including the US and France, have introduced "strict protocols" to enable the "experimental use" of chloroquine and hydroxychloroquine during the current Covid-19 crisis.

The EMA said: "Large clinical trials are under way to generate the robust data needed to establish the efficacy and safety of chloroquine and hydroxychloroquine in the treatment of Covid-19. EMA welcomes these trials, which will enable authorities to give reliable advice based on solid evidence to healthcare professionals and patients."

Catherine Drew of Pinsent Masons, the law firm behind Out-Law, is a regulatory expert in the life sciences sector. She said: "The EMA guidance highlights the need to balance the competing needs of patients throughout Europe, and indeed the world – balancing the needs of those with a new life threatening condition, where these compounds appear to offer a glimmer of hope; with the needs of those with lifelong and serious conditions who potentially risk facing shortages of medication, due to sources being redirected to others."

"The guidance also emphasises the importance of generating robust data on the safety and efficacy of these compounds for the treatment of Covid-19, achievable only through controlled use of the compounds in patients. This ties back to an earlier EMA statement on clinical trials and associated collaboration," Drew said.