In Britain, Johnson & Johnson has initiated a new late-stage trial to test a two-dose regimen of its experimental COVID-19 vaccine among thousands of volunteers, as the US drugmaker expands its trials by geography and type.
Scientists leading the trial said the UK arm of the study seeks to recruit 6,000 participants among a total of 30,000 people globally. Volunteers will be recruited at 17 sites across the UK.
Saul Faust, a professor of pediatric immunology and infectious diseases who is co-leading the trial, said that the participants would be given a first dose of either a placebo (a substance or treatment which is designed to have no therapeutic value) or the experimental shot, currently called Ad26COV2, followed by a second dose or placebo 57 days later.
In August, J&J signed a two-dose global Phase III clinical trial agreement with the British government to run a single shot of the experimental vaccine, which was launched in September, in parallel with a 60,000-person trial.
If the results of the single-shot trial are positive, the company said that the delivery of millions of doses could be simplified compared to leading competitors requiring two doses. Because if people fail to return to receive their second shot, the effectiveness of a double-dose vaccine may be affected.
Last week, rival drugmakers Pfizer and BioNtech said their potential COVID-19 shot displayed more than 90% efficacy in interim results from a late-stage study, raising expectations that pandemic disease vaccines could soon be ready for use.
But the -70 degree storage requirement of the vaccine makes it extremely challenging to be transported and stored. There are also widespread concerns that due to these difficulties, the vaccine could be accessible only to rich countries.
While a new technology known as messenger RNA is being used in the Pfizer-BioNtech vaccine, J&J’s uses a cold virus to introduce genetic material from the coronavirus into a person’s body to prompt an immune response.
The platform, called AdVac, is also used in an Ebola vaccine that was approved earlier this year.
“It’s really important that we pursue trials of many different vaccines from many different manufacturers and be able to ensure the supply both to the UK and global population,” Mr. Faust said.
Scientists leading the UK trial did not include specifics of the other countries that will participate in this two-dose trial, but said Britain was the first choice to start it. Research recruitment will be completed in March 2021 and the trial will last for 12 months.