"We need billions of doses. And different vaccines have different upsides and downsides. Like the newest one we heard about yesterday, AstraZeneca. It's easier to manufacture. So there (are) more doses that can be made, and probably at less cost," said Dr. Joseph Eron, the chief of the Division of Infectious Diseases at UNC's School of Medicine.
The cost differences arise from AstraZeneca pledging not to profit off their vaccine during the pandemic. Their vaccine will cost about $2.50 a dose, compared to $20 a dose for Pfizer's vaccine, and $15-$25 per dose for the Moderna vaccine.
Eron is also serving as an investigator for the Moderna vaccine trial.
"The Pfizer vaccine has the highest degree of difficulty. And then Moderna, once it's thawed, can be kept refrigerated for a month, so that's a little bit better. And the AstraZeneca looks like it only requires refrigeration," said Eron.
The Oxford/AstraZeneca vaccine was shown to be up to 90% effective. Both the Pfizer and Moderna vaccine slightly exceeded that efficacy rate.
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"The flu vaccine is 50-60 percent in a good year," said Dr. Eron for comparison.
In its drafted vaccine distribution plan, the North Carolina Department of Health and Human Services said it would involve rural health clinics from the start on vaccine planning. Local work groups will help indentify potential sites for mobile vaccine distribution sites, much like the mobile testing sites set up at congregate living facilities and essential businesses. Early messaging, focused on increasing trust in the vaccine, will also be targeted at rural communities and historically marginalized populations.
But the success of a distribution plan depends on which vaccine is authorized for use. The cold-chain requirements present for the Pfizer, and to a lesser extent, Moderna, vaccines could potentially add another layer of difficulty with distribution, specifically to more rural areas. The Pfizer version needs to be kept at the temperature of dry ice--minus 80 degrees Celsius.
"We use -80 freezers here. A lot of them, because we store biological samples at -80. And one -80 freezer might cost $12,000," said Dr. Tony Moody, of the Duke Human Vaccine Institute.
Still, Eron does not believe the cold-chain requirements will present a significant obstacle in distribution. He added that administering the shot itself is straightforward.
"There's not some special, zig-zag procedure, special needle, or special device," said Dr. Eron.
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While the initial results are promising, it is important to note that the studies themselves are still ongoing, and no vaccine has been approved for use.
"We still don't know how long the vaccine protection will last for. That's a big issue that people need to understand. And we only have short-term safety (data). So I think that's also important," said Dr. Eron.
The US Food and Drug Administration is expected to decide on granting emergency use authorization to the Pfizer vaccine on December 10; if approved, the first doses will likely be given to health-care workers and high-risk individuals shortly after.
"We are ready to ship vaccines within 24 hours from approval," said Dr. Moncef Slaoui, chief scientific adviser of Operation Warp Speed, on ABC's "This Week".
Moderna has committed to 20 million doses for US patients by the end of the year, enough for 10 million people, as the vaccine requires two shots. Pfizer has publicly committed to 50 million doses globally over the same time period--though no specific numbers for US patients. Oxford University and AstraZeneca hope to produce up to 3 billion doses by the end of 2021.
The manufacturing differences are borne out of different processes used to create the vaccine. Both Moderna and Pfizer used mRNA, a new method, while Oxford/AstraZeneca used a more traditional style.