As drugmakers pledge to thoroughly vet a vaccine, one company pauses its trials for a safety review.
The pharmaceutical company AstraZeneca halted global trials of its coronavirus vaccine on Tuesday because of a serious and unexpected adverse reaction in a participant, the company said.
The trial’s halt, which was first reported by Stat News, will allow the British-Swedish company to conduct a safety review. How long the hold will last is unclear.
In a statement, the company described the halt as a “routine action which has to happen whenever there is a potentially unexplained illness in one of the trials, while it is investigated, ensuring we maintain the integrity of the trials.”
The news of AstraZeneca pausing its trial came the same day the company and eight other drugmakers made a joint pledge to “stand with science” on coronavirus vaccines, reaffirming that they would not move forward with such products before thoroughly vetting them for safety and efficacy.
President Trump has repeatedly claimed that a vaccine could be available before Election Day, Nov. 3, heightening fears that his administration is politicizing the race by scientists to develop a vaccine and potentially undermining public trust in any vaccine approved.
The companies did not rule out seeking an emergency authorization of their vaccines, but promised that any potential coronavirus vaccine would be decided based on “large, high quality clinical trials” and that the companies would follow guidance from regulatory agencies like the Food and Drug Administration.
Some said the halt of AstraZeneca’s trial was evidence that the process was working as it should.
“At this stage, we don’t know if the events that triggered the hold are related to vaccination,” said Dr. Luciana Borio, who oversaw public health preparedness for the National Security Council under Mr. Trump and who was acting chief scientist at the F.D.A. under former President Barack Obama. “But it is important for them to be thoroughly investigated.”
In large trials like the ones AstraZeneca is overseeing, the company said, participants do sometimes become sick by chance, but such illnesses “must be independently reviewed to check this carefully.”
The company said it was “working to expedite the review of the single event to minimize any potential impact on the trial timeline” and that it was “committed to the safety of our participants and the highest standards of conduct in our trials.”
A person familiar with the situation, and who spoke on the condition of anonymity, said that the participant had been enrolled in a Phase 2/3 trial based in the United Kingdom. The individual also said that a volunteer in the U.K. trial had been found to have transverse myelitis, an inflammatory syndrome that affects the spinal cord and is often sparked by viral infections. However, the timing of this diagnosis, and whether it was directly linked to AstraZeneca’s vaccine, is unclear.
AstraZeneca declined to comment on the location of the participant and did not confirm the diagnosis of transverse myelitis. “The event is being investigated by an independent committee, and it is too early to conclude the specific diagnosis,” the company said.
AstraZeneca’s vaccine is currently in Phase 2/3 trials in England and India, and in Phase 3 trials in Brazil, South Africa and more than 60 sites in the United States. The company intended for its U.S. enrollment to reach 30,000.
AstraZeneca is one of three companies whose vaccines are in late-stage clinical trials in the United States.
Britain, seeing a spike in new coronavirus cases, will ban most gatherings of more than six people beginning next week, Prime Minister Boris Johnson is expected to announce on Wednesday.
“We need to act now to stop the virus spreading,” Mr. Johnson said in a statement on Tuesday. “So we are simplifying and strengthening the rules on social contact — making them easier to understand and for the police to enforce.”
The new measure, which will include fines beginning at 100 pounds (about $130), will apply to both indoor and outdoor gatherings, including private homes and parks. It is not expected to apply to workplaces, weddings, funerals or team sports.
A surge in cases this week and confusion over the current rules prompted the new measure, which is expected to take effect on Monday. About 3,000 new cases were reported on both Sunday and Monday of this week, the highest daily figures in Britain since May. About 2,500 more new cases were reported on Tuesday and 32 deaths.
The current rules allow up to 30 people for certain types of gatherings, sowing confusion and making it difficult for officials to enforce.
In an interview with Sky News on Wednesday, Health Secretary Matt Hancock said that the new rules would not be implemented until Monday because people needed time to read them.
“Every single person in the country needs to know what they are so we can together keep a grip on the virus,” he said.
As of Wednesday, Britain had recorded at least 352,000 virus cases and 41,000 deaths, according to government data.
In other developments around the world:
On the Greek island of Lesbos, a fire forced thousands of migrants to flee a camp where they had been living under a coronavirus lockdown, The Associated Press reported early Wednesday, citing the local authorities. The restrictions were imposed last week on the Moria camp after a 40-year-old asylum seeker tested positive for the virus.
India’s Health Ministry said on Tuesday that it planned to open classrooms for high school students on a voluntary basis, and only with their parents’ approval, starting Sept. 21. The vast majority of schoolchildren will continue to study online. The Taj Mahal will also open for tourism on Sept. 21, with access restricted to 5,000 people per day. India has recorded more than 4.3 million cases over all, with nearly 90,000 new infections reported on Tuesday.
Ontario, Canada’s most populous province, said on Tuesday that it would take a four-week “pause” before it considers loosening restrictions or allowing further economic reopening. Christine Elliott, Ontario’s health minister, acknowledged that schools, which began reopening across the province on Tuesday, would most likely become vectors for the virus, and said that the province’s top priority was protecting them from transmission in the community. Ontario has reported at least 43,000 coronavirus cases, according to a New York Times database, including 852 in the past week.
China’s biggest air show, originally planned for November in the southern city of Zhuhai, has been canceled because of the pandemic, its organizer said on Wednesday. The cancellation of the biennial China International Aviation and Aerospace Exhibition comes amid a steep downturn in the industry.
Quarantine breakdowns at colleges in the U.S. are leaving some at risk.
Across the United States, colleges that have reopened for in-person instruction are struggling to contain the spread of the virus among tens of thousands of students, with perhaps their most complex problem being what to do with students who test positive or come into contact with someone who has.
Many have set aside special dormitories, or are renting off-campus apartments or hotel rooms to provide isolation beds for infected students and separate quarantine units for the possibly sick.
But some undergraduates and epidemiologists say the policies have broken down, often in ways that may put students and college staff members at risk.
At the University of Alabama in Tuscaloosa and the University of Notre Dame, students have reported their classmates for violating quarantine and wandering outside. At Iowa State University, a student who was waiting for his virus test results said he was sent back to his regular dorm room where he could have infected his roommate.
And at many campuses, students with confirmed or possible infections have flooded social media platforms to describe filthy rooms, meager food rations, lack of furniture, chaotic procedures and minimal monitoring from their universities.
The policy breakdown reflects the chaotic nature of this extraordinary semester, when schools are struggling to deliver both in-person and remote classes; to identify, isolate and treat coronavirus outbreaks; and to maintain safe behavior among sometimes unruly undergraduates.
At the University of North Carolina in Chapel Hill, Brianna Hayes developed a fever after a week at school, went to campus health services and was immediately assigned to a quarantine dorm for students with virus risks. Two days later, the university informed Ms. Hayes, a first-year student, that she had tested positive and would need to move again, this time to a Covid-19 isolation dorm.
But there was no university staff in the dorm to help sick students, Ms. Hayes said, and during her week in isolation, she said, no one from the university came to check on her.
“I felt like everyone was only interested in how I was affecting others, like who I came in contact with, and then I was just left to be sick,” she said.
Amy Johnson, U.N.C.’s vice chancellor for student affairs, said the school worked hard “to facilitate an easy and comfortable transition for students,” and to keep “lines of communication open.” With more than 900 student virus cases over the last month, the university switched to online instruction in mid-August, but it has permitted some students with demonstrated needs to remain on campus.
Reporting was contributed by Mike Ives, Natasha Singer, Karan Deep Singh, Katie Thomas, Katherine J. Wu and Elaine Yu.