"Human challenge" trials of potential Covid-19 vaccines, where volunteers are deliberately infected with the disease, could become a reality after a British biotech firm signed a contract with the government to create and provide strains of the virus.

Preliminary work for the trials, which aim to speed up the process of determining the efficacy of a vaccine candidate, is being carried out by hVIVO, a unit of pharmaceutical services company Open Orphan ORPH.L, Reuters reported.

This involves creating a human challenge study model that could be used should such trials gain ethical and safety approval from regulators.

“The model development involves the manufacture of the challenge virus and the first-in-human characterisation study for this virus,” the company said.