Major Coronavirus Vaccine Trials Pending: Scientists React

Enrollment in a global trial of potential coronavirus vaccine candidates is pending after a “suspected adverse event” in a vaccinated person in the UK. It’s too early for scientists to say how this could impact the global push to develop a vaccine, but the news is on a large scale to assess vaccine safety. Waiting for the results of well-designed trials before emphasizing the importance of approving a wide range of medicines is used.

Oxford University researchers are co-developing a vaccine with the pharmaceutical company AstraZeneca. It is one of nine coronavirus vaccines in the final “Phase III” stage of testing.

Details of the adverse event, including how serious it was and when it occurred, have not been reported by Oxford or AstraZeneca. However, prior to the November presidential election, the trial cessation comes about in fear that US drugstores may face political pressure to approve the vaccine before the trial is complete.

Marie-Paule Kieny, a vaccine researcher at INSERM, the French National Institute of Health in Paris, said, “Clinical hold shows that there is a check and balance that is working despite political pressure. President-Vaccine safety is paramount,” she says.

“Oxford candidates seem very promising so far, so I hope the adverse event is unrelated to the vaccine,” says Florian, a virologist at the Ikern School of Medicine in Mount Sinai, New York City. Says Crammer. He says the decision to discontinue the trial ensures that the process of evaluating a vaccine works and only safe and effective treatments come to the market.

Tuesday is a health news site STAT Reported US Phase III Trial of Coronavirus Vaccine Candidate Suspended.. On Wednesday, Oxford University Nature Enrollment in vaccine trials in Brazil, South Africa and the United Kingdom will also be suspended.

“As part of an ongoing, randomized, global trial of the Oxford Coronavirus Vaccine, our standard review process has been initiated and we have been voluntarily vaccinated to allow independent committees to review safety data. The vaccination has been suspended,” AstraZeneca said in a statement.

“This is a routine action that occurs whenever a potentially unknown illness occurs in any of the studies under investigation. To minimize the potential impact on the study timeline. , We are working to expedite the review of single events, working on the safety of our participants and the highest standards of conduct in our exams,” said the statement.

“If the event is critical, or perhaps linked to a vaccine, it could be a decisive blow to this particular vaccine candidate. If unrelated, it could be released in a few weeks. Yes,” says Kiany.

However, without the details of the adverse event, such as the severity and timing of the adverse event, it is difficult to assess the impact on the trial and the timeline for approval, scientists say.

It was the second time that the administration of the vaccine was suspended. Said participants had previously developed neurological symptoms, Volunteer information sheet.. A safety review found that the patient had a disease of the nervous system called transverse myelitis unrelated to the vaccine.

Cross country trial

Last month, AstraZeneca plans to launch a trial of the vaccine candidate AZD1222 in the US, enrolling 30,000 adults in approximately 80 locations nationwide. Efficacy trials are underway in the UK, Brazil and South Africa, targeting a total of approximately 17,000 people. Approximately 20,000 participants in the US were given the vaccine twice and the remaining 10,000 received placebo. According to both participants and investigators are not informed of what they received A description of the study posted on Clinicaltrial.gov. Extensive testing of these people is needed before regulatory authorities such as the US Food and Drug Administration can approve the widespread use of the vaccine.

Many countries, including the United States, have preordered millions of doses of the Oxford vaccine and expect it to succeed. By the end of last month State ordered at least 2.94 billion doses — More than any other coronavirus vaccine candidate. More than one-third of these doses are purchased in the UK, Japan, US and European countries. The US Office of Advanced Biomedical Research has provided AstraZeneca more than $1 billion to develop the Oxford vaccine.

Adverse events are not uncommon in clinical trials and are often unrelated to treatment during the trial, said Paul Griffin, an infectious disease researcher at the University of Queensland in Brisbane who conducted a large clinical trial. .. For example, adverse events could include a participant being hospitalized for some reason, and even if the hospitalization was unrelated to the vaccine, it could automatically trigger a trial suspension. The study has a protocol that specifies the type of event that causes the suspension, and then there is a process to investigate whether the event is associated with a vaccine, he says. AstraZeneca’s research protocol has not been published.

It’s not uncommon, but given the issues involved in developing a safe and effective vaccine, all the details of the study need to be made public, says Paul Komesarov, a doctor and bioethicist at Monash University in Melbourne. .. “All clinical trials are publicly endorsed, the disease poses the greatest threat to humanity in 100 years, the drug discovery process is highly politicized, and the result is to secure and maintain public trust. If you can’t, you won’t succeed.”

What’s next?

Now, an independent committee reviewing AstraZeneca’s data is investigating whether adverse events occur in vaccinated participants or placebo, the researchers say. If that happens in the vaccinated person, investigators need to find out if the jab caused an adverse event. “It may be hard to find the truth,” said Jonathan Kimmelman, a bioethicist who is studying clinical trials at McGill University in Montreal, Canada.

If the event turns out to be significant and vaccine-related, it could have significant implications for the study, Griffin said. “But it’s too early to assume that it is,” he says. The first priority is to keep volunteers safe and to receive the best medical care.

“I am confident that this group will assess this adverse event very quickly and inform the results of the study,” Griffin said.

Researchers are particularly worried that the COVID-19 vaccine can cause a “spread of infection” if later vaccine recipients become exposed to the virus. Animal studies and early-stage human trials of the COVID-19 vaccine, including the Oxford / AstraZeneca candidate, have so far reported no evidence of increased disease.

Oxford vaccine Virus vector vaccine It utilizes a cold-causing “adenovirus” that is isolated from chimpanzees. The chimpanzee adenovirus is modified to express the “spiking” protein that coronavirus uses to infect human cells as it becomes unable to replicate intracellularly. Dozens of groups They say they are working on a viral vector vaccine for coronavirus, including a candidate developed by Johnson and Johnson and one co-developed by the Chinese Army and CanSino Biologics.