KUALA LUMPUR, Dec 9 — Pfizer-BioNTech’s preliminary study showed that three doses of its Covid-19 vaccine are likely to protect against the Omicron variant, while two shots may still be able to prevent severe disease.
The earliest study by the US-German pharmaceutical companies also revealed that two doses of their mRNA vaccine had a significant reduction in neutralising antibodies by more than 25 times against Omicron compared to wild-type coronavirus.
However, a third Pfizer vaccine dose increased neutralising antibody levels 25-fold. The neutralisation of the Omicron variant among participants who received a third dose a month ago was “comparable” to protection from two doses against wild-type and previous Covid-19 variants.
Pfizer-BioNTech’s lab study indicated that protection from two doses of its coronavirus vaccine may not be sufficient against Omicron, as the vaccine developers suggested a third booster dose to achieve “robust protection.”
“Although two doses of the vaccine may still offer protection against severe disease caused by the Omicron strain, it’s clear from these preliminary data that protection is improved with a third dose of our vaccine,” Pfizer chairman and CEO Albert Bourla mentioned in a press statement yesterday.
“Ensuring as many people as possible are fully vaccinated with the first two-dose series and a booster remains the best course of action to prevent the spread of Covid-19.”
At the same time, Pfizer-BioNTech has started to develop an upgraded vaccine against the Omicron variant of concern and expects to have it available in the market by March 2022.
“Our preliminary, first dataset indicate that a third dose could still offer a sufficient level of protection from disease of any severity caused by the Omicron variant,” BioNTech CEO and co-founder Ugur Sahin stated in the press release.
“Broad vaccination and booster campaigns around the world could help us to better protect people everywhere and to get through the winter season.
“We continue to work on an adapted vaccine which, we believe, will help to induce a high level of protection against Omicron-induced Covid-19 disease as well as a prolonged protection compared to the current vaccine.”
In contrast, a research study from Germany disclosed that a third dose of Pfizer’s vaccine may not be a solution for Omicron as the variant significantly evades immunity produced by a booster shot.
According to Sandra Ciesek, director of the Institute of Medical Virology at University Hospital Frankfurt, Pfizer-BioNTech’s vaccine was only 25 per cent neutralising against Omicron three months after a booster, compared to 95 per cent with Delta.
“Up to 37 times the reduction in Delta vs. Omicron,” she tweeted.
Dr Zoë Hyde, an epidemiologist and bio-statistician in Australia who commented on the Germany study, said on Twitter that all individuals who have completed their primary vaccination series, as well as those who got a third shot, are now at risk of a breakthrough infection with Omicron.
“I won’t sugar-coat things. This is a disaster,” Dr Hyde tweeted yesterday.
“People vaccinated with two doses of the Pfizer-BNT vaccine likely have no protection against infection with the Omicron strain. Protection after three doses has likely taken a big hit as well.
“What it means for severe disease is unclear.”
Dr Hyde noted that the highly contagious mutated variant can increase the spread of the disease and eventually increase the hospitalisation rate and strain health care facilities.
“Even if only a small proportion become unwell enough to need hospitalisation, this could still break health care systems. A small proportion of a large number of infections is still a big number. Remember that breakthrough cases can also get long Covid.”
Nevertheless, the first South Africa lab study on vaccine efficacy against Omicron showed that considerable protection was retained in those who were both double vaccinated with Pfizer’s shot and previously infected with Covid-19.
Researchers urged people to receive a Covid-19 booster shot to get better protection against Omicron.