Dr. William Hartman has recently had an unusually large number of people canceled.
Hartman runs one of AstraZeneca’s Phase 3 Covid-19 vaccine clinical trial sites at UW Health in Madison, Wisconsin. But last week, a handful of trial volunteers either canceled or simply did not show up for their scheduled appointments.
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“People are asking if they can withdraw from the trial,” Hartman said. Although he has so far been able to fill vacancies with people on the waiting list, he said he believes the reason for the small setback may be the apparent success of two other vaccine candidates: those made by Pfizer and Moderna.
Both companies have reported promising results from initial analyzes of their Phase 3 clinical trials. Health and Human Services Secretary Alex Azar said during a task force briefing in the White House on Thursday that he expects Pfizer to ask federal regulators for an emergency use approval for the vaccine on Friday. Moderna has said it intends to follow suit in the coming weeks. That would enable them to roll the first shots in December.
Hartman said he suspects that if such permits are actually imminent, his volunteers may choose to “wait for the vaccine that is just around the corner.”
Public health officials say it is misleading.
Dr. Stephen Hahn, commissioner of the Food and Drug Administration, said he was “concerned” about any drop in trial attendance during a “Doc to Doc” interview Thursday with NBC News senior medical correspondent Dr. John Torres, which was streamed on Facebook.
Although the data from Moderna and Pfizer are promising – both reported about 95 percent efficiency – Hahn said companies are far from the finish line. Regulators have not yet had a chance to review the raw data from both companies.
“Until we look at the data until we have a clear sense of efficiency and security, these trials should continue,” Hahn said. “I would encourage people to sign up.”
Hartman’s team at UW Health aims to enroll up to 1,000 participants. Right now there are about 150 registered.
Clearly, one or two vaccines will ultimately not be enough to fight the pandemic.
“If we have more manufacturers producing more safe and effective vaccines, we can quickly vaccinate more people,” said Dr. Buddy Creech, an infectious disease expert and director of the Vanderbilt Vaccine Research Program at Vanderbilt University Medical Center in Nashville, Tennessee.
Vanderbilt has been involved in the clinical trials with Moderna, and just last week it launched a separate trial with Johnson & Johnson’s vaccine candidate. Creech said he has been able to avoid noticeable dropouts from student volunteers by reminding people that it will be months before there is enough vaccine available for anyone who wants it.
“The number of doses available to people in our area will really be limited in the next four to six months,” Creech said. “Go ahead and sign up for clinical trials. This is a good chance to be able to contribute further in this pandemic.”
Although the FDA is green-lighting a vaccine for emergency use in the coming weeks, experts reminded those eagerly awaiting the shots that such approval is not the same as full approval.
Such approval would require more intense control by regulators – and more data from clinical trials.
“We do not have a complete idea of safety and efficiency” in the event of an emergency use approval, said Norman Baylor, president and CEO of Biologics Consulting, a biotechnology consulting firm. Baylor is a former director of the FDA’s Office of Vaccines Research and Review.
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“We need to continue and conduct the investigations so that the FDA can make a decision on whether vaccines should be approved,” he said. “We can not rest.”
Baylor said it is a “good thing” that more vaccine candidates are underway. Four graduates are in the middle of Phase 3 clinical trials in the United States In total, more than 100 are in development or other studies.
Dr. Paul Kilgore, a vaccine investigator at the Henry Ford Health System in Detroit, said having more vaccine manufacturers “provides assurance that if any manufacturer were to stop production itself temporarily, we would have a Plan A, Plan B and Plan C.”
Kilgore’s team has been involved in clinical trials with both the Moderna and Johnson & Johnson vaccine candidates. He said it was crucial to review the trials “to the end, to ensure we collect as much safety and immune response data and efficacy data as possible.”
Realistically, for the public, I do not think a vaccine will be available by April or May.
Baylor warned of other wild cards that could delay any rollout of the vaccine. Moderna and Pfizer have predicted that they could provide hundreds of millions of vaccine doses over the next few months. Although there is no reason not to believe such projections, it is possible for manufacturing problems to emerge. “What if you fall short?” Asked Baylor.
Dr. Carlos del Rio, assistant dean of the Emory University School of Medicine in Atlanta, urged Americans to remember that “despite encouraging and welcome vaccine data,” there is no vaccine available right now. “
As of Friday, the spread of Covid-19 had reached unprecedented levels in the United States and increased in every state.
“This is not a time to give up masking” and other mitigation efforts, such as hand washing and physical distance. “The world is burning out there, and realistically I do not think a vaccine will be available by April or May,” del Rio said.
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