Europe plans to ‘spare doses’ to scale up monkeypox vaccine, WHO seeks trials

There have been 27,800 cases of monkeypox – mostly among men who have sex with men – and 12 deaths worldwide this year.

According to the WHO and other government health agencies, stocks of the key Nordic Bavarian vaccine, the only licensed vaccine to prevent monkeypox and a key part of the global public health response, are scarce.

On Tuesday, the United States backed the use of a vaccine vial to deliver up to five separate doses – instead of a single dose – by squirting a smaller amount between the layers of the skin. The vaccine was designed to be injected into a layer of fat under the skin.

This so-called “dose-sparing” approach has already been tried with other vaccines, including polio and yellow fever, but evidence is limited on whether it might work for monkeypox.

“The European Medicines Agency (EMA) will discuss the possibility of a dose-saving approach,” an EMA spokesperson told Reuters, adding that the regulator would discuss the strategy with the manufacturer, the Bavarian and European Nordic countries.

The company did not respond to repeated requests for comment.

The WHO is “encouraging the use of vaccines in trials that will help gather information relevant to their use in this outbreak,” a spokesperson told Reuters by email.

According to the US Food and Drug Administration, data collected in a 2015 clinical study demonstrated that dose sparing could work without sacrificing vaccine safety and efficacy.

Meanwhile, some governments in Europe are taking other steps to expand existing supplies. For example, Britain offers only one dose of the two-dose regimen to those most at risk as a temporary measure to offer at least some protection to more people.

It is unclear whether either approach will result in adequate protection against monkeypox, which is usually a mild to moderate infection that results in flu-like symptoms and characteristic pus-filled skin lesions.

The viral disease has been endemic in parts of Africa for decades and was first reported this year outside those countries in May.

Adam Finn, a professor at the University of Bristol who works with WHO Europe to provide advice on monkeypox vaccination campaigns, said it “made sense” to assess the cost-saving approach dose” because vaccine stock-outs are a very real potential concern with the monkeypox outbreak.

(Reporting by Jennifer Rigby and Natalie Grover; Editing by David Gregorio)

By Natalie Grover and Jennifer Rigby