The Johnson & Johnson vaccine studies show it can provide safety for eight months, including against the Delta strain.
“Current data for the eight months studied so far show that the single-shot Johnson & Johnson COVID-19 vaccine generates a strong neutralizing antibody response that does not wane; rather, we observe an improvement over time,” says Dr. Mathai Mammen, head of research and development at J&J’s Janssen vaccine arm.
According to the company, one dose is enough to produce an antibody response as well as T-cells that can last for more than half a year.
“Data showed that T-cell responses — including CD8+ T-cells that seek out and destroy infected cells — persisted over the eight-month timeframe examined,” says the company.
Dr. Barouch And his colleagues have tested the Phase 1/2 trial of the vaccine on 20 participants with promising results.
Experts from Washington University in St. Louis say that Pfizer/BioNTech and Moderna vaccines protect for more than six months, maybe even years. At the moment, the Johnson & Johnson vaccine was not tested. However, according to the company:
“A single dose of the Johnson & Johnson COVID-19 vaccine generated neutralizing antibodies against a range of SARS-CoV-2 variants of concern, which increased over time, including against the increasingly prevalent and more transmissible Delta (B.1.617.2) variant, the partially neutralization-resistant Beta (B.1.351), the Gamma (P.1) variants and others, including the Alpha (B.1.1.7), Epsilon (B.1.429), Kappa (B.1.617.1) and D614G variants, as well as the original SARS-CoV-2 strain.”
Therefore, the J&J vaccine is strong enough against both COVID-19 and other SARS-CoV-2 variants. A Janssen team in the Netherlands, who have conducted their own study, have come to the same conclusion.
How many doses of the Johnson & Johnson vaccine?
Although the company said only one dose should suffice, the US National Institutes of Health is testing to see if two doses are more effective.