Pfizer ultimately did not receive government funding for research and development, though Warp Speed in July provided $1.95 billion to secure 100 million shots, a deal the government also said would support mass manufacturing.
Moderna’s late-stage clinical trial was slightly smaller than Pfizer’s, with 30,000 participants rather than its competitor’s 44,000. Both shots are roughly 95 percent effective for the general population, although Pfizer’s was more effective for adults over 65, at 94 percent to Moderna’s 86 percent.
But that may not be a statistically significant difference, said Steven Joffe, a University of Pennsylvania health policy expert and member of the Data Safety Monitoring Board overseeing several vaccine trial under the auspices of Operation Warp Speed.
“They and most of the other companies, Pfizer excepted, had a lot of help from the government and Warp Speed,” Joffe said — adding that nonetheless, Moderna’s success “is a big achievement.”
Moderna executives said Thursday at the FDA advisory committee meeting that they did not see serious allergic reactions in the trial; two incidents, one in the placebo group, were not seen to be related to the shot itself. The data comes as U.S. and U.K. regulators scramble to better understand severe reactions to the Pfizer vaccine in people with serious allergies. Those reactions happened outside of clinical trials, where people with serious allergies are rarely included.
The FDA panel voted 20-0 to recommend the vaccine, with Michael Kurilla, a National Institutes of Health scientist, abstaining because he said he was “very uncomfortable” with a blanket recommendation for people over 18 years old. Because of the severity of the pandemic and limited supplies, “I would prefer to see it more targeted to people at high risk of more threatening illness and disease,” he said.
Moderna’s vaccine has several logistical advantages over Pfizer’s. Unlike Pfizer, Moderna opted for the U.S. government to distribute its shot, handing one of the biggest challenges of the vaccination push to military personnel and commercial distributors guided by Gen. Gustave Perna, Warp Speed’s chief operating officer.
Moderna’s shot can also be stored in most regular freezers, while Pfizer’s needs ultra-cold freezers or containers filled with dry ice that make that vaccine more challenging to ship and store.
With FDA authorization expected Friday, the company faces its biggest test yet. Warp Speed officials say that more than 4 million doses are ready to ship to states by Monday, and the remainder of the country’s 200 million dose order will stream in over the next six months.
“I’m sure they’ve got good people there, but this is their first product,” said Loss. “Anytime you do something for the first time, there is the possibility of mistakes, uncertainty.”