The Johnson & Johnson Covid vaccine gives immunity that lasts at least eight months. It protects against the Delta variant as well; the company said in a statement Thursday night. According to Dr Mathai Mammen, head of research and development at J&J’s Janssen vaccine arm, “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.”
The company said one dose of vaccine evoke both T-cells and a lasting antibody response that lasted eight months. Dr Dan Barouch of Harvard Medical School and Beth Israel Deaconess Medical Center and colleagues in an early stage, Phase 1/2 trial of the vaccine tested blood taken from 20 volunteers. “These data are promising and reassuring,” Barouch said. He has submitted his findings to the BioRxiv preprint server.
According to the company, “Data showed that T-cell responses — including CD8+ T-cells that seek out and destroy infected cells — persisted over the eight-month timeframe examined.” Barouch said these are not real-world efficacy data, but T-cell and antibody response usually indicates protection.
Moderna and Pfizer/BioNTech have both said their two-dose vaccines are protective for at least six months. At Washington University in St. Louis, researchers reported earlier this week that their studies of vaccinated volunteers show that the protection from the vaccine should last more than this and even for years. They did not test Johnson & Johnson vaccines.
Barouch’s team from the vaccinated volunteers also tested blood against the most worrying variants of the virus, including the B.1.617.2 or Delta variant 1st seen in India, the P.1 or Gamma variant spreading in Brazil, and the B.1.351 or Beta variant 1st seen in South Africa.
Barouch said, “We see robust neutralizing antibody coverage of the variant.” Neutralizing antibodies are the immune system proteins that inactivate a virus before it can replicate. According to the company, A single dose of the J&J Covid vaccine creates neutralizing antibodies against a range of SARS-CoV-2 variants of concern, which increased over time.