In a laboratory trial, Johnson & Johnson’s vaccination generated almost little antibody protection against the omicron coronavirus variation, highlighting the new strain’s capacity to circumvent one pillar of the body’s defences.
The vaccine appears to provide some defense against omicron, perhaps via other means such as stimulation of immune cells, according to Penny Moore, a South African virologist. The findings are consistent with other studies that show a partial loss of potency against Covid-19 for a number of vaccines, with J&J’s antibody protection looking particularly weak in the lab test.
Moore, a professor at Johannesburg’s University of The Witwatersrand, said that laboratory experiments were conducted on blood plasma samples from people who had had two doses of the Pfizer Inc. and BioNTech SE vaccine and those or the J&J single-shot inoculation.
A measure of antibody levels, called geometric mean titers, fell from 1,419 against the original coronavirus strain to 80 against omicron among people who received Pfizer shots. The same measure fell from 303 against the original strain to undetectable levels against omicron in those who had received J&J’s shot, Moore said in an online presentation on Tuesday.
“Omicron does indeed exhibit substantial immune escape from antibodies,” she said. “The situation, I think, is even more alarming for the J&J vaccine — there was no detectable neutralization in our assay.”
J&J didn’t declined to comment on the findings, referring instead to an earlier statement that said the company is testing serum from participants in its booster studies to look for neutralizing activity against omicron while pursuing an variant-specific vaccine that it will progress as needed. The company is “confident in the robust humoral and cell-mediated immune responses elicited” by its vaccine, Mathai Mammen, head of research & development for J&J’s Janssen pharma unit, said in the statement.
