Second dose of J&J vaccine gives strong boost, company reports

PBC News:  Johnson & Johnson will submit the data to the Food and Drug Administration, which is evaluating similar studies from Pfizer and Moderna. If authorised by the agency, the Biden administration wants to provide booster shots eight months after vaccination.

The Johnson & Johnson vaccine was absent from the government’s initial booster plan, announced last week. But with the new data, the company hopes to be part of the initial distribution of additional shots, which could happen as early as September.

“We look forward to discussing with public health officials a potential strategy for our Johnson & Johnson COVID-19 vaccine, boosting eight months or longer after the primary single-dose vaccination,” Dr Mathai Mammen, the global head of Janssen Research & Development at Johnson & Johnson, said in a statement.

In February, the FDA gave emergency authorisation to Johnson & Johnson for its one-shot vaccine. A clinical trial carried out last fall and winter showed that a single shot had a 72 percent efficacy in preventing symptomatic COVID-19 among US participants. In the trial, none of the vaccinated volunteers were hospitalized or died.

Johnson & Johnson carried out its clinical trial before the delta variant became widespread, leaving open the question of how well the vaccine worked against the highly contagious form of the virus. But in a study released earlier this month, South African researchers found that a single shot of the Johnson & Johnson vaccine was up to 95 percent effective against death from the delta variant, and reduced the risk of hospitalization by 71 percent.

In its new study, Johnson & Johnson tracked 17 volunteers from last year’s clinical trial. Six months after vaccination, their level of antibodies had changed little.

That’s different than the pattern seen with the Moderna and Pfizer-BioNTech vaccines. Those shots initially produce higher levels of antibodies, but their levels then drop over several months.