OUWA.org – Pfizer Says Experimental COVID-19 Vaccine Is More Than 90% Effective. Pfizer’s experimental COVID-19 vaccine appears to be working. The vaccine was found to be quite 90% effective, consistent with clinical results released by the corporate Monday.
That news comes from an interim analysis of a study involving 43,538 volunteers, 42% of whom had “diverse backgrounds.”
Each participant got two injections spaced 21 days apart. The analysis compared the number of cases of COVID-19 among the volunteers getting the vaccine with an approximately equal-sized group of volunteers who got an injection of a liquid that did not contain the vaccine. (Read also Pfizer and BioNTech Covid-19 Vaccine is Strongly Effective)
In a news release from Pfizer and its partner BioNTech, the corporate said results from 94 evaluable cases of COVID-19 among study participants indicated the vaccine is quite 90% effective in preventing COVID-19. The Food and Drug Administration set a minimum effectiveness bar at 50%.
This is the primary COVID-19 vaccine in development to possess data showing that it exceeded that mark.
“I tend to be an optimist. I have been in vaccine development for over 35 years,” said Dr. William Gruber, senior vice chairman of vaccine clinical research and development at Pfizer. “But this is often extraordinary, and that I think it speaks well not just for the potential of this vaccine but potentially other vaccines that are out there in development for COVID-19.”
“This result’s towards the high end of expectations,” said an emailed comment from Shane Crotty, professor at the middle for communicable disease and Vaccine Research, La Jolla Institute for Immunology. “Greater than 90% efficacy at preventing disease, with 94 COVID-19 cases to gauge, is a superb outcome! it might be good to ascertain more of the info, but those are very convincing numbers.”
While promising, this analysis alone doesn’t provide enough information about the vaccine for Pfizer to ask the FDA for permission to distribute it.
The agency has informed manufacturers that it wants a minimum of two months of follow-up data from a minimum of half the volunteers. The FDA says the rationale for that requirement is that the majority of dangerous side effects from a vaccine occur within two months of getting the ultimate injection. Pfizer says that data won’t be available until the third week in November.
The company didn’t say how serious the COVID-19 cases were that occurred within the study, or whether any of them required hospitalization.
Natalie Dean, a biostatistician at the University of Florida, says she’s cautiously optimistic but expecting more data.
“There remain many open questions, like how well the vaccine is functioning across different age groups, how well it’s preventing infection and severe disease,” Dean wrote in an email to NPR. “But for the pre-specified primary endpoint of laboratory-confirmed symptomatic disease across the trial population, the numbers look excellent .”
The Pfizer vaccine trial is what’s referred to as an event-driven study. It doesn’t last for a specified period of your time. Instead, the study will continue and won’t be considered complete until it’s recorded a complete of 164 cases of COVID-19 among all the volunteers.
As described in its publicly released protocol, the corporate had planned to conduct four interim analyses, when a proscribed number of COVID-19 cases had occurred. The results released Monday are from the other, the corporate has agreed with the FDA to forgo the primary analysis.
