Pfizer's 6-dose-per-vial OK boosts its supply numbers. The catch? Special syringes are required

When pharmacists discovered a sixth dose could be pulled from vials of Pfizer and BioNTech’s vaccine, rather than the original five, it looked like a solution to supply-constrained vaccine rollouts.

But now that the FDA has approved that tactic, Pfizer's counting those extra doses toward its established orders, The New York Times reports—which means it won't help boost immediate supplies.

In fact, it might actually cut them. Special syringes needed to extract that extra shot aren’t necessarily on hand, meaning states could wind up with fewer doses than expected, not more.

Pfizer is reportedly working with the U.S. government to pair the right syringes with vaccine shipments—and count doses accordingly—but that's not official or certain. The company had not responded to a request for comment by press time.

Pfizer and BioNTech early this month ratcheted up their low-end vaccine production estimate from 1.3 billion to 2 billion vaccine doses, which Pfizer chief Albert Bourla, Ph.D., speaking at his company’s J.P. Morgan healthcare conference presentation, attributed to “out of the box manufacturing.”

That new goal also depends on the dose-per-vial count, though. The FDA on Jan. 6—after much prodding from Pfizer—confirmed that each vial of the drugmaker’s shot, now dubbed Comirnaty, was good for six doses. The label change marked an immediate 20% increase to the company’s vaccine capacity, which Bourla, speaking at JPM, said would contribute to the partners’ new, 2 billion dose production goal.

Thing is, the FDA’s approval for a sixth dose came with a caveat: "Low dead-volume syringes and/or needles can be used to extract six doses from a single vial,” the agency’s updated fact sheet says. “If standard syringes and needles are used, there may not be sufficient volume to extract a sixth dose from a single vial."

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Many parts of the U.S. are already armed with those low dead space syringes, “but not every place,” CNN’s chief medical correspondent, Sanjay Gupta, M.D., said Friday. McKesson, tapped in the U.S.’ vaccine distribution efforts, is making special syringe kits available, he added, while Becton Dickinson, the world’s largest syringe maker, told The Washington Post that low dead space syringes weren’t as plentiful as standard injector devices.

Meanwhile, the Biden Administration on Friday outlined plans to use the Defense Production Act to lock down supplies of the specialized syringes, the Post reported. An anonymous source told the newspaper that Pfizer and the administration had hammered out a deal to track which shipments are armed with low dead space syringes and which are not.

Under that plan, vials without the specialty syringes would still count toward five doses out of Pfizer’s overall 200-million dose order, while those joined by low dead space injectors will count as six. The administration's Covid Response team had not responded to Fierce Pharma by press time.

“For Pfizer, the FDA approval of the overfill dose means it can fulfill its contract, which calls for doses and receive full payment from the U.S. with almost 7 million fewer vials,” Sam Buffone, a partner with the whistleblower law firm Black & Buffone, told The Post. “But many of those sixth doses might ultimately be discarded because distribution centers lack the proper tools.” 

Neither Pfizer nor Operation Warp Speed were immediately available for comment on the situation. 

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The brouhaha over Pfizer’s sixth dose follows a protracted—and public—head-to-head between the company and European Union member states after it came out that Pfizer and BioNTech would temporarily squeeze initial vaccine deliveries to Canada and Europe as it wraps an upgrade on a manufacturing plant in Puurs, Belgium.

Several countries—including Poland, France and Italy—are considering lawsuits or fines if further delays are announced, while Yahoo Finance reported last week that EU members are facing a similar scramble to lock down specialty syringes, faced with the prospect of paying for six doses in each vial, regardless of their ability to extract all of them.

Europe's shot rollout faced further complications last week after AstraZeneca revealed it too would lower initial deliveries to Europe, thanks to "reduced yields at a manufacturing site within our European supply chain," a spokesperson told Fierce Pharma.

BioNTech, for its part, told Reuters it plans to provide 50 million low dead space syringes to countries around the world at no profit.