Even before it’s evident that a modification is needed, vaccine producers are scrambling to update their COVID-19 doses against the newest coronavirus danger, just in case.
Experts doubt that today’s doses will become ineffective, but they believe it’s vital to see how quickly firms can develop a reformulated dosage and demonstrate that it works, because whatever happens with omicron, it won’t be the last mutant.
“Omicron is sounding the fire alarm,” says Omicron. Whether it turns out to be a false alarm, it would be great to know if we can truly do this — roll out a new vaccine and be ready,” said University of Pennsylvania immunologist E. John Wherry.
It’s still too early to tell how immunizations will fare against omicron. This week’s early clues were mixed: Two Pfizer dosages, according to preliminary lab testing, may not prevent an omicron infection, but they may protect against severe disease. And a booster injection might raise immunity to the point where it can accomplish both.
In the next weeks, better answers are expected, and authorities in the United States and other nations are keeping a careful eye on the situation. Because of omicron or any other mutant, the World Health Organization has created an independent scientific group to advise on whether the injections need to be reformulated.
But officials haven’t said what might prompt such a severe response: if vaccination protection to dangerous illnesses declines, or if a new mutation spreads more quickly?
Pfizer’s vaccine partner BioNTech CEO Ugur Sahin noted shortly before omicron’s discovery, “This is not trivial.” A business might bring a new formula to market. “However, what if another firm submits a bid with a different variant?” We don’t have a plan that everyone agrees on.”
It’s a difficult choice, and the virus is outpacing science. Just last autumn, vaccination experts in the United States questioned why boosters hadn’t been redesigned to target the extra-contagious delta variety — only to discover that the next dangerous mutant, omicron, is neither a delta descendant nor a very near cousin.
If vaccinations do need to be tweaked, another concern arises: should an omicron booster be given separately or as part of a combo shot? Should it target the original strain along with omicron, or the currently dominant delta variant plus omicron, if it’s a combination? This is all we know thus far.
COVID-19 vaccines function by inducing the creation of antibodies that detect and destroy the coronavirus’s spike protein, and many are manufactured using cutting-edge technology that allows for quick updates. The Pfizer and Moderna vaccines are the quickest to modify, as they contain genetic instructions telling the body to create harmless copies of the spike protein — and that messenger RNA can be altered to match new mutations.
According to Pfizer’s chief scientific officer, Dr. Mikael Dolsten, the company hopes to have an omicron-specific candidate available for the Food and Drug Administration to examine in March, with some initial batches ready to ship around the same time.
Moderna estimates that an omicron-specific candidate will be available for testing in 60 to 90 days. Johnson & Johnson, which produces COVID-19 vaccines using a different technology, is also looking into prospective improvements.
Pfizer and Moderna have previously prepared trial dosages to match delta and another variety known as beta, injections that were not required but were useful practice.
Until now, the original vaccinations have provided some cross-protection against previous versions. Even if immunity to omicron isn’t as strong, Dr. Anthony Fauci, the leading infectious disease expert in the United States, is optimistic that the large antibody increase induced by booster doses would compensate.
Antibodies aren’t the only line of protection, according to preliminary lab data provided by Pfizer on Wednesday. Vaccines also stimulate T cells, which can help prevent serious disease if someone becomes sick, and Pfizer’s first testing revealed that omicron has no effect on these cells.
With each dosage, memory cells emerge, capable of producing new and somewhat different antibodies.
“You’re essentially teaching your immune system not just to cope better with existing varieties, but to deal with novel variants as well,” Dolsten explained.
The degree to which a mutant is aggressive also influences whether or not the vaccination should be reformulated. Although Omicron appears to be easily transmitted, early studies from South African experts suggest that it may produce milder infections than prior forms.
The FDA has stated that businesses will not require large trials of altered vaccinations, but rather modest ones to see if patients who receive the revised injection have immune responses that are comparable to those who received the original, highly successful vaccines.
Volunteers trying experimental omicron-targeted injections aren’t expected to provide data until at least February, according to Wherry.
In one dose, flu vaccinations protect against three or four distinct influenza viruses. If an omicron vaccine adjustment is needed, officials will have to determine whether to create a separate omicron booster or add it to the original vaccination — or maybe even attempt a different mix as they did with the flu.
A COVID-19 combination shot has been shown to function in the past. A so-called bivalent booster including the original vaccination plus a beta-specific dosage generated a larger antibody rise in a small Moderna research than either the original Moderna booster or its experimental beta-specific injection.
Furthermore, scientists are already developing next-generation vaccinations that target portions of the virus that are less likely to evolve.
Omicron is “another critical wake-up call,” according to Wherry, not only to vaccinate the globe but also to offer more varied methods for doing so.
