FDA halts vaccine trial in Bay Area

Bay Area researchers who had been poised to start enrolling patients in a coronavirus vaccine trial have suspended those plans after the vaccine developers and federal regulators halted the trial in the United States over safety concerns.

Phase 3 trials for the vaccine, made by the drug company AstraZeneca and Oxford

University — considered one of the frontrunners in the race for a vaccine — were temporarily halted worldwide Sept. 6 after a participant in the United Kingdom developed a neurological illness. The trials, which are being conducted in a number of countries, resumed shortly after in Britain, South Africa and Brazil. But the U.S. Food and Drug Administration has not allowed the study to restart in the United States.

It is unclear if, or when, the FDA may decide whether to resume the U.S. portion of the trial. Neither the FDA nor AstraZeneca would say why other countries have resumed the trials and the U.S. has not, each directing the question at the other. An FDA spokeswoman said the agency cannot comment on the status of an investigational new drug application. AstraZeneca said it is working with the FDA and the agency will decide when the U.S. trial can resume.

The development comes at a time of heightened concerns that federal coronavirus policies are becoming increasingly politicized as the national election nears. From the appointment of controversial policy researcher Scott Atlas to the presidential coronavirus task force, to the inconsistent messaging around masks and testing guidance from the

CDC, public health experts are increasingly concerned that decisions that should be driven purely by science are now influenced by political motives. Concerns escalated Wednesday, when President Trump called new, stricter FDA guidelines for authorizing vaccines “a political move” and said the White House might not approve them.

In the case of the AstraZene

ca trial, FDA prudence could be perceived as a positive.

“There is heightened interest and scrutiny about COVID vaccines, so from a public perspective I can see how an event such as this could raise some concern,” said Dr. Bali Pulendran, an immunologist at Stanford Health Care. “But, essentially, all the appropriate steps are being taken. The FDA is doing a thorough investigation and the trial is being halted for that purpose . ... I’m glad it was early on and the trial was halted as we find out what’s going on with this.”

AstraZeneca has paused and restarted its global trials twice, each time after a U.K. participant developed an unexplained neurological illness. One participant developed symptoms of transverse myelitis, a rare and serious condition involving inflammation of the spinal cord. The condition was divulged in a July information sheet, a document given to potential participants to inform them of possible risks. It is unclear if the problem was caused by the vaccine, or if the symptoms developed independently.

Experts say it is not uncommon in large clinical trials for some participants to experience an adverse event, or harmful reaction, after receiving an experimental vaccine or medicine. It is also not unusual for regulators in one country to pause and resume a trial there, while regulators in another country continue putting it on hold while they investigate safety concerns. In a way, they said, it is reassuring regulators are taking seriously their role to closely examine safety. It may just be a matter of time before the FDA allows the trials to resume here.

“This is good news in the sense that it indicates the system is working,” said Dr. Richard Feachem, a professor of epidemiology and biostatistics at UCSF. “There was an adverse event, the trial was halted, the case was investigated. The U.K. regulator said continue, carry on. The U.S. regulators are still investigating. So this is routine.”

Two San Francisco sites were planning to begin enrollment for the trial: Zuckerberg San Francisco General Hospital and Bridge HIV, a research unit within the San Francisco Department of Public Health. Each planned to enroll 250 participants. Both have put their participation on hold until the FDA decides it is safe to proceed. Neither San Francisco site had enrolled any patients at the time the U.S. trials were halted.

“We hope to have more information soon,” said a statement from the San Francisco COVID Command Center. “Safety is our number one priority and we will not be moving forward with next steps until we have approval from the U.S. FDA and Data and Safety

Monitoring Board to proceed.”

The Data and Safety Monitoring Board is an independent panel of experts that reviews data from clinical trials for safety. The board includes experts in the field that do not have ties to the drug’s sponsors.

Sutter East Bay AIDS Center, part of Alta Bates Summit Medical Center in Oakland, was also considering enrolling 500 patients in the trial. The center has not yet enrolled participants and is awaiting information from the FDA and AstraZeneca about efforts to resume the U.S. trial before finalizing its decision on whether to participate, a Sutter official said.

The trial was slated to enroll 30,000 people across 80 U.S. sites. At the time the U.S. trials were paused, the vaccine had been administered to some patients at other U.S. sites, but not at the San Francisco sites.

The AstraZeneca vaccine is one of 10 vaccines that are in Phase 3 trials globally, the last stage before the FDA can consider whether it is safe and effective for widespread use. Phase 3 trials are when vaccines get tested on tens of thousands of people — compared to the dozens or hundreds of people during Phases 1 and 2. Johnson & Johnson, Moderna and Pfizer are also developing vaccines that are in Phase 3.

Bay Area participants are being recruited in at least two other Phase 3 vaccine trials. Pfizer, which is partnering with German company BioNTech, last month began enrolling Kaiser Permanente members in Northern California. And Johnson & Johnson on Wednesday announced plans to enroll patients for its Phase 3 trial, including at two Bay Area sites — Stanford University Medical Center in Palo Alto and the VA Medical Center in San Francisco. Stanford and the VA are tentatively scheduled to begin enrollment Sept. 30 and Oct. 19, respectively, according to Johnson & Johnson.