Vaccines made specifically to tackle the BA.5 subvariant of COVID should be ready by this fall, Dr. Anthony Fauci, U.S. President Joe Biden’s chief medical advisor, told The Hill this week. But the vaccines could suffer from one major flaw: BA.5-specific vaccines may become less effective once the Omicron subvariant is replaced by another strain, a real possibility given that dominant strains have been replaced with more competitive forms of the virus roughly every six months during the course of the pandemic.
“You’re dealing with a moving target,” he said on The Hill’s Rising. “There’s always the possibility that you’re going to have the evolution of another variant…And hopefully, if that occurs, it will vary off from the BA.5 only slightly—in the sense of being a sub-sublineage of it, and not something entirely different.”
The White House and vaccine makers are already trying to head off a worse outcome by accelerating efforts to develop a universal COVID vaccine that would protect against multiple variants.
On Tuesday the White House hosted a summit with Pfizer, Moderna, health officials, and other pharmaceutical executives to discuss a universal COVID vaccine. “These are vaccines that are going to be far more durable, that are going to provide far longer-lasting protection, no matter what the virus does or how it evolves,” Ashish Jha, the White House COVID-19 response coordinator, told Stat News about the summit.
Pfizer may have an early lead.
On Wednesday, Pfizer announced the start of phase II trials for its new “next-generation” universal vaccine candidate that would protect against both the original ‘wild-type’ COVID strain and Omicron variants.
“I’m besides myself,” Dr. Elias Said, director at Regenerative Medical Health, wrote on Twitter about the announcement. “We need a pan-coronavirus vaccine.”
Some experts believe creating a universal COVID vaccine that would protect against all variants, and potentially future ones, is far preferable to making a new vaccine every time a new variant pops up.
Eric Topol, founder of the Scripps Research Translational Institute, says that “variant chasing” and the development of variant-specific boosters will never keep up with the pace of emerging new variants. “Variant chasing is a losing strategy,” he tells Stat News. “It’s temporally flawed and unacceptable.”
Nonetheless, Omicron-specific boosters appear to be on their way. In late June, the Food and Drug Administration (FDA) asked vaccine makers to update their vaccines for BA.5. As of this week, 82% of cases recorded in the U.S. are BA.5. The BA.5 wave has led to an explosion of cases, even if they’re not reflected in official statistics. The U.S. is currently reporting 131,000 cases per day in the last week, but sewage samples show that the figure may be several times higher and potentially at record levels.
Pfizer, which had been working on Omicron-specific vaccine tailored to target the previously dominant BA.1 subvariant, said it would tweak its vaccine to fit BA.5.
“Omicron has newly evolving sublineages that have outcompeted BA.1 and exhibit a trend of increasing potential for immune escape,” Dr. Ugur Sahin, CEO of BioNTech, which originally developed the vaccine marketed by Pfizer in the U.S., said in a statement at the time. “We will therefore remain vigilant and are prepared to rapidly adapt our Omicron-adapted vaccine candidates to emerging sublineages if epidemiological and laboratory data suggest.”
Moderna, meanwhile, announced on July 11 that its BA.5 booster induced “significantly higher neutralizing titers,” which measure a body’s immune response to a vaccine,
“Our bivalent platform continues to demonstrate better performance than the current booster,” Stephane Bancel, Moderna CEO, said in a statement. “This superior breadth and durability of immune response following a bivalent booster has now been shown in multiple Phase 2/3 studies involving thousands of participants.”
Both Pfizer and Moderna say that the variant-specific vaccines could be ready by this October.
Biden, who tested positive for COVID last week, on Wednesday acknowledged how evasive the BA.5 variant is, even as vaccines, boosters, and therapeutics are blunting the deadliness and severity of the current wave.
“The reality is that BA.5 means many of us are still going to get COVID even if we take the precautions,” Biden said at the White House’s Rose Garden on Wednesday. “[But] if you get COVID, you can avoid winding up in a with a severe case” due to vaccines and treatments, Biden said.
