AstraZeneca nixes variant-specific COVID vaccines, eyes annual shots

There is little value in developing vaccines that target specific coronavirus variants, according to Bruce Mungall, Asia area medical director of vaccines and infectious diseases at AstraZeneca, a multinational pharmaceutical company.

“In terms of whether there’s value in chasing a new updated vaccine for a specific variant, I think there’s very limited incremental value in doing that,” he said. “I’m relatively confident that the current vaccines will continue to provide very high levels of protection against serious outcomes.”

Unlike Pfizer and BioNTech, which announced this June that they were evaluating Omicron-adapted COVID-19 vaccine candidates, AstraZeneca hopes to move to “more sustainable approaches” such as annual shots, Mr. Mungall said at a roundtable discussion on Aug. 5.

He pointed out that on the logistics side, manufacturing millions of variant-specific doses is a “very difficult and time-consuming process,” in light of how quickly the Omicron coronavirus subvariant spreads.

“To do that fast enough to react to a new variant is very challenging and expensive,” he said. “Every time a company gives you a new vaccine, I can guarantee you: it’s not going to be cheaper than the previous [one]. You’re going to pay an incremental cost every time there’s a new vaccine.”

Mr. Mungall said that current vaccines are effective in preventing hospitalization and death.

On Monday, the Department of Health (DoH) reported that there were 27,331 additional COVID-19 cases from Aug. 1 to Aug. 7, a 13% increase from a week before.

A 2022 study in Thailand that assessed the effectiveness of a mixed (heterologous) four-dose COVID-19 vaccine schedule found that a fourth dose of any of the COVID-19 vaccines studied, including AstraZeneca’s, were 75% effective in preventing Omicron infection.

The vaccine effectiveness of the AstraZeneca vaccine (73%) was similar to that of mRNA vaccines (71%).

“In Thailand, they use different vaccines for their third and fourth doses,” Mr. Mungall said. “The broader message is that any vaccine you have available for boosters is good for you.”

Across the age groups studied, data showed that a three-dose mixed schedule provided 98% protection against severe infection or COVID-19-related death.

A single death in a person with comorbidities was observed following a fourth dose booster, according to a preprint published June 28 in Research Square.

Meanwhile, researchers at Airfinity, a London-based predictive health analytics firm, took the Imperial College London’s research on deaths averted per country, and examined which vaccines were administered in each of these countries.

Using this methodology, it reported in July that AstraZeneca and Pfizer/BioNTech saved 6.3 million and 5.9 million lives, respectively. Sinovac, furthermore, saved 2 million lives; Moderna, 1.7 million lives.

More than 71 million individuals, or 92.06% of the target population in the Philippines, have been vaccinated against COVID-19 as of Aug. 7. Over 16 million individuals have had their booster shots.

In an Omicron world, a third dose is probably necessary, Mr. Mungall said.

“A booster dose will probably be necessary — either a third or a fourth — depending on your risk status,” he said. “There is a very similar effectiveness of all vaccines as booster doses.” — Patricia B. Mirasol