PLATINUM trial
Research type
Research Study
Full title
Placebo-controlled randomised trial of tecovirimat in non-hospitalised monkeypox patients (PLATINUM)
IRAS ID
1006115
Contact name
Peter Horby
Contact email
ISRCTN Number
ISRCTN17461766
Research summary
Monkeypox is a viral disease that usually causes a pustular rash, and can occasionally cause severe complications. It does not usually circulate in the UK, but in May 2022 a large outbreak was detected with ongoing spread from person to person. At the moment, most patients with monkeypox are treated only for their symptoms, such as pain and itch. However, an antiviral drug called tecovirimat has been developed that can stop the virus replicating and may speed recovery. This has been shown to be effective in treating monkeypox in animals, and no significant side effects have been identified when giving tecovirimat to healthy volunteers, but there has never been a clinical trial in people with monkeypox. This trial aims to find out whether a two-week course of tecovirimat pills can increase the speed of recovery of people with monkeypox who are well enough to be at home. Half of the patients will receive tecovirimat and half will receive an identical looking placebo so we can compare how quickly each group recovers. All patients will receive the standard care from the NHS, and patients are free to stop taking the tablets or participating in the study if they wish.
Patients who join the trial will be followed for 4 weeks, and will be asked to answer a few questions every day about their rash using an online form. We will also call participants weekly to review their progress, and will ask them to take weekly swabs of their throat and skin, which will be collected by a courier. The study is coordinated by staff at the University of Oxford, and all information about participants will be kept securely and confidentially on University computers. We aim to recruit 500 participants in total, which should allow us to identify or rule out any meaningful benefit of tecovirimat.
Lay summary of study results: Tecovirimat is an antiviral drug that has been proposed as a treatment for mpox (monkeypox). The PLATINUM trial was set up during the 2022 UK mpox outbreak to find out if a 2-week course of tecovirimat tablets would improve the speed of recovery from mpox.
The trial was open to patients across the UK who had been diagnosed with mpox and who did not require admission to hospital. Trial participants were randomly allocated to receive either tecovirimat or matching placebo (dummy) tablets. Participants recorded their symptoms daily, and the main outcome was the time taken for mpox skin blisters to scab over. Other outcomes were the time taken for mpox blisters to heal completely, and the length of time that living virus could be detected in swabs from the throat and from mpox blisters. The number of mpox infections in the UK fell soon after the PLATINUM opened, so recruitment remained low and the trial closed at the end of 2023 without reaching its recruitment target.
In total 35 patients were recruited. We did not find any benefit of tecovirimat on any of the trial outcomes, nor did we find any harmful effects. However, the small number of participants recruited meant that we could not rule out a benefit of treatment.
REC name
South Central - Berkshire Research Ethics Committee
REC reference
22/SC/0336
Date of REC Opinion
18 Aug 2022
REC opinion
Further Information Favourable Opinion