Interim results from a Phase 1/2 study indicate Johnson & Johnson's SARS-CoV-2 vaccine elicits a long-lasting immune response, Bloomberg reports.
Unlike SARS-CoV-2 vaccines from Pfizer-BioNTech and Moderna that have received emergency use authorizations in the US that require two doses, J&J's is a one-dose regimen. The candidate vaccine, dubbed Ad26.COV2.S, targets the SARS-CoV-2 spike protein.
As they report in the New England Journal of Medicine this week, researchers from J&J and elsewhere conducted a Phase 1/2 trial in which 805 participants were randomized to receive the vaccine at a low or high dose or placebo in a single-dose or two-dose format. They found that 90 percent of the participants had neutralizing antibodies against the virus by 29 days after their first dose and all had them by 57 days after the first dose. Their antibody levels remained stable for the 71 days of the study.
"Looking at the antibodies, there should be good hope and good reason that the vaccine will work," Paul Stoffels, J&J's chief scientific officer, tells Bloomberg, which notes the company expects results from its late-stage trial soon.
According to Politico, J&J may seek an EUA for its vaccine as soon as this month, but it notes that the company has been beset by production delays. The company originally planned to deliver 12 million doses by the end of February, but may now need until April to hit that target, it adds.