Pfizer asks US FDA to approve Covid-19 booster shots for all adults

Older people and vulnerable groups are already eligible for additional vaccine doses

A patient waits to be called for a Covid-19 vaccination booster shot outside a pharmacy in Denver. AP

Pfizer asked US regulators on Tuesday to approve booster doses of its Covid-19 vaccine for anyone 18 or older, a step that comes amid concern over the potential increased spread of the coronavirus during holiday travel and gatherings.

Older Americans and other groups particularly vulnerable to the virus have had access to a third dose of the Pfizer and BioNTech vaccine since September. But the Food and Drug Administration has said it would move quickly to expand the option for boosters to younger people if warranted.

The pharmaceutical company has submitted early results of a new study to make the case that it is time to expand the booster campaign.

While all three vaccines used in the US continue to offer strong protection against severe Covid-19 illness and death, the shots’ effectiveness against milder infections can wane over time.

Pfizer’s new study, comprising 10,000 people, concluded boosters can restore protection against symptomatic infection to about 96 per cent. Side effects were similar to those seen with the company’s first two shots.

In a median of 11 months after their last Pfizer vaccination, trial participants were given either a third dose of the vaccine or a placebo. Researchers tracked any infections that occurred at least a week later and so far, five cases of symptomatic Covid-19 have been observed among booster recipients compared to 109 cases among those who received the placebo.

The administration of US President Joe Biden had originally envisioned boosters for all adults, but faced a stinging setback in September when the FDA’s scientific advisers rejected extra Pfizer doses for all.

The panel was not convinced that young, healthy people needed another dose, particularly when most of the world’s population remains unvaccinated.

Still, under today’s policies, two out of every three vaccinated adults are expected to qualify for boosters within the next few months — and many who do not can nonetheless receive an extra shot as most vaccine providers do not check qualifications.

The current rules state that people who initially received Pfizer or Moderna vaccinations are eligible for a booster six months after their last shot if they are 65 or older, or are at high risk of contracting Covid-19 due to underlying health problems, their job or living conditions.

Because the single-dose Johnson & Johnson vaccine has not proven as effective as its two-dose competitors, any recipient of this vaccine can receive a booster two months later. And regardless of the initial brand of vaccination, the US has cleared mixing and matching for boosters.