Pfizer booster ‘95 per cent effective’ at preventing Covid
Trial results have found that having a booster dose of the Pfizer-BioNTech Covid-19 vaccine is more than 95 per cent effective at preventing disease.
The findings, released by the two companies that developed the shot, have been described as the first efficacy results from a “randomised, controlled Covid-19 vaccine booster trial”.
There were more than 10,000 participants in the trial and they had all received two doses of the vaccine.
Half received a third dose and the others were given a placebo, with the third dose administered an average of 11 months after the second.
Researchers recorded whether participants developed symptomatic Covid-19 at least seven days after receiving the booster, with people followed up for an average of two and a half months.
Only five cases were recorded among the participants who received a booster shot, while there were 109 cases in the placebo group.
That gives the booster shot an efficacy – or effectiveness at preventing disease – of 95.6 per cent.
Prof David Taylor, professor emeritus of pharmaceutical and public health policy at University College London, said the results indicated “having a booster is an extremely sensible idea” for people in atrisk groups.
“The message to everybody, including if you’re 50 or 60 or over, is having a booster dose after six months or longer is extremely sensible,” he said.
Ugur Sahin, chief executive and co-founder of BioNTech, said the results added to the “body of evidence” that the vaccine protected “a broad population of people from this virus and its variants”.
“Based on these findings, we believe that, in addition to broad global access to vaccines for everyone, booster vaccinations could play an important role in sustaining pandemic containment and a return to normalcy,” he said.
Pfizer and BioNTech said detailed analysis of the results showed the efficacy of a booster shot was not affected by age, gender, race, ethnicity, or any other serious medical conditions a person had.
The companies plan to share the results with regulators, including the Food and Drug Administration in the US and the European Medicines Agency.
A booster programme using the Pfizer-BioNTech vaccine that began in Israel in July has been credited with helping the country overcome its fourth wave of Covid-19.
Infection rates fell faster in people over the age of 80, who were given boosters first, than in other age groups, suggesting that a third dose of vaccine improved a person’s immunity, which may have waned over time after the second dose.
Other countries are also introducing booster drives, including the UK, which began a programme last month focused on over-50s and other vulnerable groups.
In August, people in Abu Dhabi who had previously received two doses of the Sinopharm vaccine were told to have a booster.
This month, the UAE authorised booster shots of the Pfizer-BioNTech and Russian-developed Sputnik vaccines for people over the age of 60 and members of other vulnerable groups.
The third dose was to be given at least six months after the second.
Prof Taylor said it was uncertain at the moment whether
people would need to have vaccination boosters indefinitely to protect them against the disease.
“For the next few years, it does look like especially the older population will need top-up immunisation,” he said.
“Whether that will be twice-yearly or yearly we don’t know.”