Monkeypox, a member of the smallpox family of viruses, has historically been rare outside west and central Africa. However, in May this year, an outbreak was identified in the UK, followed by cases appearing in multiple other countries outside Africa. On 23 July this year, the World Health Organization declared monkeypox to be a Public Health Emergency of International Concern. Typical symptoms of monkeypox include a rash with painful blisters, which may be widespread or affect just one part of the body. Other symptoms can include fever, muscle ache, and swelling of lymph glands. Monkeypox usually gets better without treatment but this can take several weeks and, rarely, there may be serious complications.
Although vaccines developed for smallpox may reduce the risk of catching monkeypox, there are currently no proven therapeutics to speed recovery in those who develop the disease. The Placebo-controlled randomised trial of tecovirimat in non-hospitalised monkeypox patients (PLATINUM) study will test the efficacy and safety of tecovirimat, an antiviral treatment originally developed for smallpox.
Tecovirimat (also known as TPOXXÒ) prevents the virus from leaving infected cells, stopping its spread within the body. It was licensed earlier this year by the Medicines and Health products Regulatory Agency (MHRA) for monkeypox based on promising results from initial studies in animals and evidence of safety in healthy human volunteers. It is currently in use for the treatment of patients with severe complications of monkeypox who are admitted to hospital. However, to date there have been no clinical trials to confirm whether the drug can help monkeypox patients recover from the disease.
PLATINUM is being led by Sir Peter Horby, Professor of Emerging Infections and Global Health at the University of Oxford and the Director of the new Pandemic Sciences Institute, and Sir Martin Landray, Professor of Medicine & Epidemiology at Oxford Population Health, the joint chief investigators of the Randomised Evaluation of COVID-19 (RECOVERY) trial. The study also involves experts from the UK Health Security Agency, Chelsea and Westminster Hospital NHS Foundation Trust, and the University of Liverpool, who have experience in the clinical assessment and laboratory analysis of human monkeypox infections in the UK.
Professor Sir Peter Horby said:
‘Monkeypox is a distressing and sometimes dangerous infection. For the benefit of current and future patients worldwide who have been diagnosed with monkeypox, we need definitive evidence that tecovirimat is safe and effective. Although the early data on tecovirimat are promising, only a randomised clinical trial will provide the level of evidence we need to treat patients with confidence. PLATINUM will provide that evidence.’