Federal officials have reportedly scrapped plans to expand access to second COVID-19 booster doses this summer, opting instead to pressure vaccine-makers Moderna and Pfizer-BioNTech to produce their next-generation BA.5-targeting boosters even faster than before, possibly in September.

Currently, people ages 50 and over, as well as those 12 and up with certain health conditions, can received a second COVID-19 booster dose. But, with the ultratransmissible BA.5 wave threatening more infections and reinfections at a time when vaccine protections are fading, officials earlier this month toyed with the idea of opening second boosters to all adults. At the time, they were expected to decide the matter within the following weeks.

That decision window has now closed. And although BA.5 is still raging, the Biden administration has reportedly abandoned the plan to instead focus on the new booster vaccines for those 12 and up, which were previously expected to roll out in October and November.

In June, the Food and Drug Administration advised vaccine makers to create a bivalent next-generation booster for a fall rollout that could thwart a winter wave of infection. The bivalent shot would again target the spike protein of the ancestral strain of SARS-CoV-2, but also the mutated spike protein shared by the BA.4 and BA.5 subvariants. The regulator’s thinking—along with its committee of independent expert advisers—was that the bivalent booster targeting BA.4/5 would likely offer better protection against the currently circulating subvariants.

Uncertainty

But this bivalent booster plan is a gamble. There is little to no data indicating that the BA.5-targeting bivalent booster will be significantly better than the current booster at preventing infection and disease. It’s also unclear how long BA.5 will remain the dominant subvariant. Though there’s no clear successor nipping at BA.5’s heels so far, waves of omicron subvariants have come in a rapid sequence in the last few months, with BA.5 being the third omicron subvariant to achieve dominance since March when BA.2 reigned, followed by the rise of BA.2.12.1. It’s conceivable that BA.5 will be in decline by the time the next-generation boosters are available, even with the hastened timeline of an early-to-mid-September rollout.

In June, vaccine makers suggested that an October to November rollout would be a heavy lift. But unnamed officials in the administration have told reporters that the companies have now offered assurances that they can get them out sooner, in September.

The officials offered some insight into the administration’s deliberations. For instance, top infectious disease expert Anthony Fauci and White House Pandemic Response Coordinator Ashish Jha both advocated for offering more second boosters now, in the summer, while transmission is high and protection is waning.

But the FDA and the Centers for Disease Control and Prevention reportedly pushed for focusing on the fall campaign. Their thinking is that a summer booster drive so close to the fall could confuse Americans on when to re-up their protection and potentially cause some to lose confidence in the shots if boosters are offered in such quick succession. There’s also the scientific concern that yet another vaccine dose targeting the ancestral strain—which is no longer circulating—could bias immune responses in a way that makes them less effective at fighting off variants. (Though this argument has not been used to deter people over 50 from getting a second booster.)

Last, there’s also the time constraint: If people get second boosters now, it could delay them from getting the bivalent booster in the fall. Or, if people got two boosters close together—a month or two apart—it could render the second shot useless.

“You can’t get a vaccine shot Aug. 1 and get another vaccine shot Sept. 15 and expect the second shot to do anything,” Shane Crotty, a virologist at the La Jolla Institute for Immunology, told The New York Times. “You’ve got so much antibody around, if you get another dose, it won’t do anything.”

Mixed messages

Still, it’s unclear why fall booster availability couldn’t stretch over several months to accommodate different boosting windows. That is, for those who want a second boost now, why couldn’t they simply wait until November or December to get the bivalent booster? In a press briefing earlier this month, CDC Director Rochelle Walensky directly argued for this scenario: that shots in late summer would not preclude fall boosters.

“As we’ve looked at the cadence of where we’ve needed to get boosts before, it’s been four, five months,” Walensky said. “We anticipate that that’s going to be a similar cadence. We also really want to emphasize that there are many people who are high risk right now, and waiting until October/November for their boost—when, in fact, their risk is in the moment—is not a good plan,” she added. “So, we really do want to say ‘Now get your boost. We have every anticipation that the data will suggest that you will be eligible for a [bivalent] boost in the fall.'”

Expert opinion on the booster plan is mixed. Some experts align with federal officials’ plan to focus on the fall, creating a simpler, potentially more impactful booster drive. “I think this is the right call,” Dr. Celine Gounder, a senior fellow at the Kaiser Family Foundation, told NPR. “If you get a booster now with the original formulation of the vaccine, this may in fact be counter-productive.”

But others called for expanded access to boosters now. Eric Topol, director of the Scripps Research Translational Institute, posted a string of critical questions on Twitter, including why unused boosters that might otherwise go to waste are not being offered to people who are at higher risk, such as health care workers under the age of 50.

Robert Wachter, chair of the department of medicine at the University of California, San Francisco, is also in favor of offering more second boosters now. “You’re talking about, you know, literally hundreds of millions of people who are at a higher risk than they need to be for months,” Wachter told NPR. “And that will mean potentially millions of preventable infections, certainly thousands of preventable hospitalizations, and probably hundreds of preventable deaths.”

Currently, the US is logging an average of nearly 130,000 new COVID-19 cases a day, though that is certainly a significant undercount given the use of at-home testing. Hospitalizations are averaging around 44,000 per day, up 11 percent over the past two weeks. Intensive care stays are up 13 percent, to over 5,000 per day. And average daily deaths are at 438, according to data tracking by The New York Times.

https://arstechnica.com/?p=1870442