Around 500 patients will take part in the PLATINUM trial at the University of Oxford to study an antiviral which aids in monkeypox recovery.

The virus has been declared a global health emergency, and is spreading rapidly in other countries, as well as the UK. Monkeypox infection usually improves on its own without treatment, but some cases can be severe, and can require hospitalisation. Recovery from infection can take weeks, and there can be serious complications involved.

Meanwhile, the UK government has bought stocks of the smallpox vaccine to try to halt its spread. The virus can be spread through close contact with an infected person. It has not been scientifically described as a sexually-transmitted infection, but anyone with the virus should abstain from sex while they have symptoms.

As part of the PLATINUM trial, some participants will be treated twice-daily with tecovirimat tablets while they recuperate from the virus in their own home. Others will receive a placebo instead.

Tecovirimat, also known as Tpoxx, prevents the virus from leaving infected cells, thereby stopping its spread within the body. The antiviral can help people with monkeypox recover more quickly, and shorten the time that they are infectious to others.

Tecovirimat was initially developed to treat illness caused by poxviruses. While it has been shown to improve recovery from monkeypox in animals, there is currently limited data on its use in human infections, according to the PLATINUM team.

However, the drug has been administered on over 400 healthy people in order to test its safety, and no concerns have been identified. It was approved as the first medicine to treat smallpox in 2018.

“The aim is to find a treatment that can help people get better quicker and get out of quarantine,” said Professor Sir Peter Horby, one of the PLATINUM trial researchers at the University of Oxford.

Minister for Public Health, Maggie Throup, said: “This government-funded study is an important step to finding a treatment which can help speed up the recovery of those who have monkeypox.”

She added: “Vaccines remain our best defence against the spread of monkeypox – we urge all those eligible to come forward when contacted, and report any symptoms to NHS 111.”