New Concerns Are Raised About The AstraZeneca Vaccine

Update: Initial trial data that was released yesterday by AstraZeneca — the pharmaceutical company behind a COVID-19 vaccine that hasn't yet been approved in the U.S. — has been called into question.

"The [Data and Safety Monitoring Board] expressed concern that AstraZeneca may have included outdated information from that trial, which may have provided an incomplete view of the efficacy data," a statement by the National Institute of Allergy and Infectious Diseases this morning stated. The Washington Post called the statement "a highly unusual rebuke."

In information provided on Monday, March 22, AstraZeneca claimed that initial data from its large-scale trial showed that the vaccine was 79% effective at preventing symptomatic COVID-19. The NIAID statement said, "We urge the company to work with the DSMB to review the efficacy data and ensure the most accurate, up-to-date efficacy data be made public as quickly as possible." This data will be thoroughly reviewed by independent committees before the FDA and CDC determines whether the vaccine should be approved for use in the U.S.

This isn't the first roadblock for the AstraZeneca vaccine. Earlier this month, Europe enacted a temporary ban against it, when reports of it causing blood clots and unexplained bleeding surfaced. These side effects were very rare, and following an investigation, the European Medicines Agency (EMA) concluded that the vaccine offered more benefits than risks.

AstraZeneca, the pharmaceutical company behind the latest COVID-19 vaccine to release the results of its clinical trial, is looking to join the ranks of vaccines already approved in the United States. On Monday, the company announced that their vaccine was found to be 79% effective against the spread of the coronavirus in the U.S. and that they would be applying for approval for usage in April, according to the Associated Press.

The news of the AstraZeneca vaccine's overall effectiveness comes after Europe enacted a temporary ban against it following reports of blood clots and unexplained bleeding in people who received it. Out of the millions of injections across the continent, about 30 cases of blood clots forming in the body came to light, prompting leaders from countries including France and Germany to stop the import of the vaccine out of public concern. However, the European Medicines Agency (EMA), after investigating the issue, concluded on Thursday that there were more benefits than risks in relation to the usage of the AstraZeneca vaccine.

"This is a safe and effective vaccine," Emer Cooke, the executive director on EMA, said during a press briefing on Thursday, as reported by Al Jazeera. "If it were me, I would be vaccinated tomorrow."

Although skepticism around this particular vaccine has reached the U.S., there's no evidence to support it. Medical experts have stood in AstraZeneca's corner throughout the pushback. Many have highlighted that the vaccine has proven to be effective in what it sought to do in the first place: protect people from the spread of COVID-19.

"Although the AstraZeneca vaccine is not yet approved for use in the USA, I hope that it soon will be," Dr. Paul S Pottinger, MD, a professor at the University of Washington's Department of Medicine, Division of Allergy & Infectious Diseases, told Refinery29. "This is because it has been found to be very safe and highly protective against COVID-19 in very large and well-designed clinical trials."

On whether or not the AstraZeneca vaccine played a role in the development of blood clots in certain patients, Dr. Pottinger notes that they weren't a side effect detected during larger clinical trials and is doubtful of a causal relationship between clots and the vaccine. "The risk of being harmed or even killed by COVID-19 is certainly greater than this theoretical and unproven risk of blood clots," he added.

Despite the uproar caused by the few blood clots cases, the AstraZeneca vaccine isn't even the first widely distributed vaccine to be connected to this side effect: Blood clots were reported to have formed in some patients after the usage of the human papillomavirus (HPV) vaccine Gardasil during the late 2000s to the mid-2010s. After further exploration from the Food and Drug Administration (FDA), 90% of people who reported blood clots had underlying risk factors, including genetic clotting abnormalities and smoking.

"It was the Danes who put the kibosh on Gardasil several years ago over a very vague pain syndrome," said Dr. John D. Grabenstein, RPh, PhD, the general manager of Vaccine Dynamics, noted in his defense of the AstraZeneca vaccine. "Stopping a vaccination program should take more than the identification of an adverse event, it should be when it's rising above a baseline value, not just when something bad happened in a vaccinee."

Popular forms of birth control pills, which are widely available and commonly used, are also known to increase the risk of blood clotting in a woman's body up to four times thanks to the increased production of estrogen, according to the Cleveland Clinic.

Still, even in their defense of the AstraZeneca vaccine, the cautious approach taken by European medical experts has been understood to a degree by experts here in the U.S.

"It's early and so I think we have to be cautious," said Dr. Norman Baylor, the President and CEO of Biologics Consulting. "They were very clear this was out of an abundance of caution. You can look at the science and you can also look at perception. I'm only speculating, but I think they felt perception-wise, this was the best thing to do. The verdict is still pending."

Should the AstraZeneca vaccine get approved for usage in the U.S., it certainly won't be the first vaccination that comes with a risk of some sort. In the long run, its hypothetical approval will lead to more vaccine accessibility for those who need it.