Pfizer’s CEO, Albert Bourla, promised the world speed last June, as the Delta variant was poised to take the world by storm. If an ultra-mutated version of SARS-CoV-2 emerges, he said, his company could have a variant-specific shot ready for rollout in about 100 days—a promise he repeated in November when COVID Omicron emerged. With the 100-day mark quickly approaching and no clinical-trial data insight, the company appears unlikely to meet its goal.
When I inquired about the timeline for this supercar, Pfizer responded, “When we have the data analyzed, we will share an update.” Moderna, which began developing an Omicron vaccine around the same time, plans to make its debut in late summer. Even if Pfizer had made good, and Omicron vaccine would not have made a significant difference. The variant’s record-breaking wave is receding in many parts of the world. A bespoke vaccine in 100 days would have been an unprecedented achievement, but Omicron was simply “too fast” for a cooked-to-order shot to beat, according to Soumya Swaminathan, the World Health Organization’s chief scientist.
Overall, we got lucky this time: our original-recipe vaccines still work quite well against the variant, especially when administered as a trio of jabs—enough that some researchers have wondered if we’ll ever need the elusive Omivax. But Omicron won’t be the last antibody-evading variant to splinter off the SARS-CoV-2 tree, which means vaccines will have to keep coming as well. There will be difficult decisions to make about what triggers might prompt a whole new variant-specific vaccine campaign, as well as how we will manage the time shift. That said, we don’t have to accept a bleak future of endless catch-up, with shots always lagging strains. Vaccine updates may not be required all that frequently, but when they are, we can be ready to respond quickly. Rather than racing after SARS-CoV-2 every time it surprises us, we could keep a closer eye on the virus and use the information we gather to act more deliberately.
The WHO formed a new technical advisory group in September, tasked with recommending ingredient changes to COVID vaccines as needed; Swaminathan envisions the committee working in tandem with the one that calls the shots for flu. However, over time, the conditions that necessitate immediate action for COVID vaccines may become less common. When coronaviruses settle into a population, they are thought to metamorphose more slowly and less dramatically than flu viruses, which could mean a less frantic variant pummelled than what we’ve seen so far. Some experts also believe that as the world continues to accumulate infections and vaccinations, our immunity to this new coronavirus will improve. Our flu defenses have always been a little shaky—vaccine effectiveness for these shots doesn’t start out particularly strong, then plummets rather quickly. If our defenses against SARS-CoV-2 become more robust, and the virus genetically quiets, we may need to rework COVID vaccines less frequently than we do for flu.
The pitfalls of pivoting from one spike version to the next are one of the reasons why this “whack-a-mole approach” to chasing single variants must end, according to Raina MacIntyre, a member of the WHO’s technical advisory group on COVID-19 vaccines and a biosecurity expert at the University of New South Wales in Australia. Future vaccines should ideally protect against multiple variants with a single injection. A simple first step would be to combine several spikes into a single shot, such as an Omicron-original combo or an Omicron-Delta-original triple threat. We may eventually discover a universal formula that protects against all variants, including those we “don’t know about yet,” according to Holcroft. If the flu is any indication, that could be a huge task: Even after many years of research, we have yet to find a cure for that disease. We don’t yet have a strong enough sense of all the evolutionary paths the virus could take with SARS-CoV-2; we may not be able to execute a wider-range shot until we better understand our adversary. Despite this, Swaminathan remains optimistic about the vaccine pipeline. “I’m fairly certain it’s scientifically feasible,” she said. “The question is no longer, ‘Can we do it?’ “It’s ‘We can.'”