Covid-19 roundup: J&J booster shot data show promise; CDC's ACIP meeting this week to discuss Pfizer boosters
J&J revealed a summary of new Covid-19 vaccine data today, including new results showing booster shots may help with protection.
A Phase III study (ENSEMBLE 2) looked at booster shots at two different points in time: a second shot 56 days after the first shot, or a second shot six months after the first. The eight-week shot showed increased protection against symptomatic Covid-19, with the following levels of protection:
- 75% protection against moderate to severe Covid-19 globally.
- 94% percent protection against moderate to severe Covid-19 in the US alone.
- 100% percent protection against severe Covid-19 at least 14 days post-final vaccination.
That booster also came with a four- to sixfold increase in antibodies. The six-month booster showed a nine- to twelvefold increase in antibodies, regardless of age. Full data will be available in the coming months, according to J&J’s statement.
Other results that J&J released include full data from a study on the effectiveness of a single dose and data from a real world study looking at people who received the shot outside a clinical trial — and how well they did.
On a single dose, data showed 74% effectiveness for Covid-19-related infections and 89% for Covid-related hospitalizations.
The real-world study compared 390,000 people who got the J&J shot to more than 1.5 million unvaccinated people matched on age, location and sex. Data from this study showed the J&J shot was 79% effective for Covid-19-related infections and 81% for hospitalizations.
J&J said in a statement that they have provided data to the FDA and plan to submit it to other regulators. — Paul Schloesser
CDC meeting to review Pfizer booster data
The CDC’s Advisory Committee on Immunization Practices will meet tomorrow and Thursday to discuss a third dose of Pfizer/BioNTech’s Covid-19 vaccine, according to an agenda posted late Monday.
Several outstanding questions need to be resolved prior to the meeting, including FDA’s issuance of either an EUA or an approval for the booster dose, and a determination on who exactly should receive the booster.
FDA’s adcomm of outside vaccine experts last week roundly rejected Pfizer/BioNTech booster shots for all individuals older than 16, by a 16-2 vote Friday afternoon. But then the committee unanimously voted for boosters for the 65-and-older population and individuals at high risk of disease due to occupational exposure or comorbidities. This positive vote centered on an EUA — not the supplemental BLA for which Pfizer had applied.
ACIP’s meetings, which typically occur after an approval or an EUA, will discuss the safety and immunogenicity for a 3rd Pfizer dose, as well as safety monitoring for third doses of mRNA vaccines, and modeling the potential impact of booster doses in nursing home residents. — Zachary Brennan
First clinical data for low-cost Covid vaccine shows acceptable safety and potent immunogenicity
As part of a wider push to bring cheaper Covid-19 vaccines to low- and middle-income countries, researchers said yesterday that a new vaccine that can be cheaply made in chicken eggs showed an acceptable safety profile and strong immunogenicity in a Phase I trial.
The results, published in a pre-print and not yet available in a peer-reviewed journal, could jumpstart a way for flu vaccine manufacturers to manufacture Covid-19 vaccine doses.
The study from Thailand enrolled 210 people, finding that the vaccine candidate, known as NDV-HXP-S, solicited predominantly mild adverse events like injection site pain, fatigue, and headache, and there were no vaccine-related serious adverse events.
The authors noted: “The vaccine was strongly immunogenic in a formulation and dose dependent manner, inducing levels of vaccine-homologous anti-S IgG and virus neutralising antibodies that exceeded by several fold the levels measured in 14-day convalescent sera from consecutive cases of health care workers with mild to moderate COVID-19 illness in 2020.” — Zachary Brennan
Poland recommends booster shot for those over 50
Poland will recommend a booster dose of the COVID-19 vaccine for people over 50 as well as healthcare workers, a deputy health minister said on Tuesday, according to Reuters.
The UK also announced plans last week for booster shots to be given to healthcare workers, those over 50 and those who are particularly vulnerable to the virus, which could total about 30 million people. This push for boosters across the UK and Europe comes as the Biden administration is expected to soon announce that it’s purchasing hundreds of millions more doses of the Pfizer/BioNTech vaccine to donate to the world. — Zachary Brennan