Johnson & Johnson’s coronavirus vaccine provides immunity that lasts for at least eight months and appears to provide adequate protection against the worrying delta variant, the company said in a statement Thursday night.
“Current data from the eight months studied thus far shows that the Johnson & Johnson single-dose COVID-19 vaccine generates a strong neutralizing antibody response that does not diminish; rather, we see improvement over time,” said Dr. Mathai Mammen, head of research and development for J & J’s Janssen vaccine division, said in a statement.
The company said that one dose of the vaccine elicits a long-lasting antibody response and generates immune cells called T cells that also last for eight months.
Dr. Dan Barouch of Beth Israel Deaconess Medical Center and Harvard Medical School and colleagues analyzed blood drawn from 20 volunteers in an initial Phase 1/2 trial of the vaccine.
“These data are promising and reassuring,” Barouch told Citizen Free Press. Barouch has submitted his findings to BioRxiv’s prepress server.
“The data showed that T cell responses, including CD8 + T cells that seek out and destroy infected cells, persisted throughout the eight-month period examined,” the company said.
These are not real-world efficacy data, but the antibody and T-cell response generally indicates protection, Barouch said.
Pfizer/BioNTech and Moderna have said that their two-dose vaccines protect for at least six months and researchers at Washington University in St. Louis reported earlier this week that their studies of vaccinated volunteers indicate that the protection of the vaccines it should last much longer than that – even for years. They didn’t test the J&J vaccine.
Barouch’s team also tested the blood of vaccinated volunteers against the most worrisome variants of the virus, including the delta or B.1,617.2 variant that was first detected in India, the B.1,351 or beta variant that was first seen. once in South Africa and the P.1 or gamma variant that spreads in Brazil.
“We see strong coverage of neutralizing antibodies from the variant,” said Barouch. Neutralizing antibodies are immune system proteins that inactivate a virus before it can replicate.
“A single dose of Johnson & Johnson’s Covid-19 vaccine generated neutralizing antibodies against a variety of worrying variants of SARS-CoV-2, which increased over time, including against the increasingly prevalent and more transmissible delta ( B.1,617.2), partially neutralization resistant beta (B.1,351), gamma variants (P.1) and others, including alpha (B.1,1.7), epsilon (B.1,429), kappa (B. 1,617.1) and D614G variants, as well as the parent strain SARS-CoV-2,” the company said.
Separately, a team from Janssen in the Netherlands studied blood drawn from eight vaccinated volunteers in the company’s Phase 3 trial and found similar results against the variants.
Early Thursday, J&J said a second dose or a booster dose of its vaccine would not be necessary.
Dr. Anthony Fauci agreed. “Regarding the idea of potentiating, there is a lot of talk about that, but at this point I think we still have to remember that, in fact, the J&J vaccine is a highly effective vaccine that has been recommended very clearly and has received authorization. for emergency use,” Fauci, who is director of the National Institute of Allergy and Infectious Diseases, said in a briefing at the White House on Thursday.
However, J&J, in conjunction with the US National Institutes of Health, is conducting tests to see whether giving two doses of its vaccine will provide better protection.