5 Important Questions About Pfizer’s COVID Vaccine
By Arthur Allen
Wednesday, November 11, 2020 (Kaiser News) – Pfizer’s announcement on Monday that its COVID-19 injection appears to prevent nine out of 10 people from contracting the disease has pushed its stock price up. Many reports have described the vaccine as if it were our deliverance from the pandemic, although few details have been released.
There was certainly something to be said: Pfizer’s vaccine is made up of genetic material called mRNA encapsulated in tiny particles that carry it into our cells. From there, it stimulates the immune system to make antibodies that protect against the virus. A similar strategy is employed in other leading COVID-19 vaccine candidates. If mRNA vaccines can protect against COVID-19 and, presumably, other infectious diseases, this will be a new momentum.
“This is a truly historic first,” said Dr Michael Watson, the former chairman of Valera, a subsidiary of Moderna, which is currently conducting advanced trials of its own mRNA vaccine against COVID-19. “We now have a whole new class of vaccines on our hands.”
But historically, important scientific announcements about vaccines have been made through peer-reviewed medical research articles that have undergone extensive review of study design, findings, and hypotheses. and not through company press releases.
So, did Pfizer’s stock deserve its double-digit percentage increase? The answers to the following five questions will help us find out.
1. How long will the vaccine protect patients?
Pfizer says that as of last week, 94 out of about 40,000 people taking part in the trial became ill with COVID-19. Although he did not state exactly how many patients had been vaccinated, the 90% efficacy figure suggests that this was a very small number. Pfizer’s announcement concerns people who received two snapshots between July and October. But that doesn’t say how long the protection will last or how many times people will need boosters.
“It’s a reasonable bet, but still a bet that protection for two or three months is similar to six months or a year,” said Dr. Paul Offit, a member of the Food and Drug Administration panel who is likely to ‘review the vaccine for approval in December. Normally, vaccines are only licensed when they show that they can protect for a year or two.
The company has not released any security information. To date, no serious side effects have been revealed and most tend to occur within six weeks of vaccination. But scientists will need to keep an eye out for rare effects such as immune boosting, a serious illness caused by the interaction of a virus with immune particles in some vaccinated people, said Dr Walt Orenstein, professor of medicine at the ‘Emory University and former director. from the Centers for Disease Control and Prevention vaccination program.
2. Will it protect the most vulnerable?
Pfizer has not disclosed the percentage of its trial volunteers from groups most likely to be hospitalized or die from COVID-19 – including people 65 and older and those with diabetes or obesity . This is a key point because many vaccines, especially against the flu, may not protect the elderly while protecting the young. “To what extent are these 94 people of the general population, especially those most at risk?” asked Orenstein.
The National Academy of Medicine and the CDC have both urged older people to be among the first groups to receive vaccines. It is possible that the vaccines in development by Novavax and Sanofi, which are expected to begin late-phase clinical trials later this year, may be better for the elderly, Offit noted. These vaccines contain immunostimulating particles like those contained in the Shingrix vaccine, which is very effective in protecting the elderly against shingles.
3. Can it be deployed effectively?
Pfizer vaccine, unlike other advanced tests, should be supercooled, on dry ice at about 100 degrees below zero, from the time it is produced until a few days before injection. MRNA is rapidly self-destructing at higher temperatures. Pfizer has developed an elaborate system to transport the vaccine by truck and specially designed cases to vaccination sites. Public health workers are trained to handle the vaccine as we speak, but we are not sure how well it will work if the containers are left in the Arizona sun for too long. Improper handling of the vaccine along the way from the factory to the patient would make it ineffective, so people who received it might think they were protected when they were not, Offit said.
4. Could a premature announcement affect future vaccines?
There is currently no way of knowing whether the Pfizer vaccine will be best overall or for specific age groups. But if the FDA approves it quickly, it could make it more difficult for manufacturers of other vaccines to conduct their studies. If people know there is an effective vaccine, they may refuse to participate in clinical trials, in part because they are concerned about being given a placebo and being left unprotected. This is because it may be unethical to use a placebo in such trials. Many vaccines will be needed to meet the global demand for protection against COVID-19, so further studies are crucial.
5. Could the Pfizer study accelerate future vaccines?
Scientists are taking a keen interest in whether the small number of people who received the real vaccine but still got sick produced lower levels of antibodies than vaccinated individuals who remained healthy. Blood studies of these people would help scientists find out if there is a “correlate of protection” for COVID-19 – a level of antibodies that can predict whether a person is protected from the disease. If they had this knowledge, public health officials could determine whether other vaccines in production were effective without necessarily having to test them on tens of thousands of people.
But it is difficult to build such roadmaps. Scientists have never established correlates of immunity to pertussis, for example, although vaccines have been used against these bacteria for nearly a century.
Still, this is good news, said Dr. Joshua Sharfstein, associate dean of the Johns Hopkins Bloomberg School of Public Health and former deputy commissioner of the FDA. He said: “I hope this will make people realize that we are not stuck in this situation forever. There is hope ahead, whether it’s this vaccine or another.
This KHN story first appeared on California Healthline, a service of the California Health Care Foundation.
Kaiser Health News (KHN) is a national information service on health policy. This is an editorially independent program of the Henry J. Kaiser Family Foundation which is not affiliated with Kaiser Permanente.
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