I still wonder if the vax rate would’ve stalled out had J&J’s vaccine not been temporarily halted earlier this year.
Booster dose of J&J's COVID-19 vaccine shows 75% effectiveness
(Ref: CNBC, The Wall Street Journal, ABC News, U.S. News & World Report, CNN, Investing.com, TheStreet, PR Newswire)
September 21st, 2021
By: Anna Bratulic
Johnson & Johnson on Tuesday said results from the Phase III ENSEMBLE 2 study showed that a booster of its single-dose COVID-19 vaccine Ad26.COV2.S increased protection against symptomatic illness, demonstrating efficacy of 75%, rising to 94% in people in the US, when given two months after the initial shot. In addition, the viral vector vaccine afforded 100% protection against severe or critical disease at least two weeks after the booster.
"We now have generated evidence that a booster shot further increases protection against COVID-19 and is expected to extend the duration of protection significantly," remarked chief scientific officer Paul Stoffels. The new data may help Johnson & Johnson convince the FDA to greenlight a booster shot to some 14.8 million Americans who have so far received Ad26.COV2.S, which is currently the only single-dose coronavirus vaccine
authorised in the US for emergency use.
ENSEMBLE 2 tested the efficacy of two Ad26.COV2.S doses, given 56 days apart, versus placebo, in adults regardless of whether they had comorbidities. Johnson & Johnson said that overall, there were 14 cases of moderate-to-severe/critical COVID-19 in the trial, compared to 52 for placebo. In the US, there was one case in the vaccine group, versus 14 in the placebo arm. Meanwhile, the company noted that there were eight instances of severe/critical COVID-19 in the placebo group, compared to none among those who got the booster shot.
Booster appears more protective after longer gap
Johnson & Johnson also elaborated on some promising
booster data first reported last month. It said that when a second dose of Ad26.COV2.S was given two months after the initial shot, antibody levels rose four- to six-times higher than what was seen after the first. Those levels rose even further with an extended gap between doses – a booster shot at six months after the initial dose elicited a 12-fold jump in antibodies, when measured four weeks after the extra shot was given. The company noted that all increases were irrespective of age.
The Biden administration had been hoping to begin a mass booster rollout using mRNA-based COVID-19 vaccines this week, although the plan has met with
pushback from those who think there is not enough evidence to do that yet. Late last week, an FDA advisory panel
voted against giving out third doses of Pfizer and BioNTech's COVID-19 vaccine Comirnaty for use in the general population, but did recommend booster doses for people 65-plus and high-risk populations. A final decision by the FDA is expected any day now.
Moderna is also
seeking an FDA nod for a booster dose of its vaccine mRNA-1273. Anthony Fauci, the US government's top infectious diseases expert,
said in the last few days that data needed to determine the advisability of booster shots of Moderna and Johnson & Johnson's COVID-19 vaccines is just "weeks away."
Real-world study
Meanwhile, Johnson & Johnson also reported on Tuesday evidence from a real-world study in the US that it said were "consistent" with the pivotal Phase III ENSEMBLE trial that was used to garner the current authorisation for its vaccine. The study analysed data from 390,000 people who received Ad26.COV2.S versus approximately 1.5 million unvaccinated matched individuals, and included predictors for COVID-19 infection severity conducted from March to late July 2021.
Johnson & Johnson said vaccine effectiveness was 79% for COVID-19-related infections and 81% for hospitalisations overall. Protection against hospitalisations was higher in people under 60 than it was for older individuals, at 86% and 78%, respectively.
