US launches trial to combat monkeypox

The United Kingdom has launched a trial to test a monkeypox treatment to help combat a recent outbreak of the virus that has infected more than 40,000 people worldwide.

There are currently no proven therapeutics to speed recovery in people who develop monkeypox, which can cause blistering of the skin and that can be life-threatening in rare cases.

The trial will explore the potential of the antiviral tecovirimat, which is a medication designed to treat smallpox, a close relative of monkeypox.

A single vaccine is used against both viruses, and researchers are hopeful tecovirimat will prove similarly effective in a dual role.

The UK National Institute for Health and Care Research, or NIHR, commissioned the study, which is being run by the same team that tested potential treatments for COVID-19.

The NIHR has already begun recruiting volunteers for the trial.

“Monkeypox is a distressing and sometimes dangerous infection,” said trial leader Peter Horby, who is a professor of emerging infections at University of Oxford. “Although the early data on tecovirimat are promising, only a randomized clinical trial will provide the level of evidence we need to treat patients with confidence.”

The current global outbreak of monkeypox represents the first time the disease has spread widely outside West and Central Africa. The first cluster of infections outside endemic nations occurred in the UK in May, where more than 3,200 infections have now been confirmed, according to Our World in Data.

The virus has spread through much of Europe, with Germany now experiencing a similar level of infections to the UK, and Spain reporting more than 6,200 cases, including two deaths.

The United States now has the most confirmed infections globally, with almost 16,000, and Brazil has reported close to 3,800 cases.

“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,” Horby said.

The trial will recruit 500 people who have become infected with monkeypox. Half of the volunteers will receive a placebo, and half will be provided with a 14-day course of tecovirimat, which they will take as a twice daily pill.

In order to find out whether tecovirimat helps patients recover faster than the placebo, researchers will assess the rate at which skin lesions heal, as well as the time it takes for throat and lesion swabs to return a negative test for the virus. The team will also monitor the proportion of patients who require hospitalization during the trial.

In a related development, the UK’s National Health Service has announced a trial at three hospitals to test the efficacy of a smaller vaccine dose against monkeypox because so-called fractional dosing could help stretch existing supplies.