AstraZeneca Rushes to Provide Updated Vaccine Data as NIH Raises Questions

In yet another setback for AstraZeneca, U.S. health officials raised concerns that the company included outdated information in its interim analysis of data from its U.S. phase 3 vaccine trial, prompting AZ to say it will release the results of its primary analysis by Thursday.

Late Monday night, the data and safety monitoring board (DSMB) observing AZ’s trial reached out to the NIH’s National Institute of Allergy and Infectious Diseases (NIAID) with fears that AZ’s announcement of its positive interim analysis results included out-of-date trial data.

In response, the NIH implored AZ to review the vaccine efficacy data with the monitoring board and publicly unveil the most current data as quickly as possible, saying the misstep “may have provided an incomplete view of the efficacy data.”

AZ agreed Tuesday to immediately work with the monitoring board to share its primary analysis with the most recent efficacy data and vowed to publicly share the results of its primary analysis “within 48 hours.”

During an interview Tuesday, NIAID Director Anthony Fauci labeled the incident an “unforced error” that could do nothing but undermine the public’s trust in vaccines but said that AZ’s shot is most likely a “very good vaccine” and will ultimately receive or be denied an Emergency Use Authorization (EUA) based on the FDA’s evaluation.

“The data really are quite good, but when they put it into the press release it wasn’t completely accurate, so we have to keep essentially trying as hard as we can to get people to understand that there are safeguards in place,” Fauci said. “I think the DSMB picking up this discrepancy was an example of a safeguard, and at the end of the day, all of this is going to be decided by the FDA.”

The company acknowledged that the efficacy numbers it announced Monday were based on an interim analysis with a data cut-off of Feb. 17, but it also noted that it reviewed the preliminary assessment of its trial’s primary analysis and found the results consistent with the interim analysis data it had just shared.

Still, this is only the latest in a string of problems for the British-Swedish company’s vaccine that may fuel public skepticism about the inoculation. AZ’s U.S. trial has suffered delays that have pushed back the company’s timeframe for requesting a EUA, and confusion was previously raised following a dosing error during its UK trial, with the company and Oxford University researchers giving explanations that appeared to conflict.

AZ has also continually failed to meet its supply commitments in Europe to the extreme frustration of the European Commission, and its vaccine additionally was the focus of a blood clot scare across the bloc that led to the temporary halting of AZ vaccinations in more than a dozen countries. The EMA and the UK have concluded that the vaccine was not responsible for an increased risk of blood clots (DID, March 19).

Alongside its unveiling of the interim analysis findings on Monday, which showed a 79 percent overall effectiveness against symptomatic infection and full protection against severe COVID-19, AZ announced its intent to file for a EUA with the FDA in the first half of April. The company said that it would have 30 million doses immediately ready for the U.S. upon the granting of a EUA (DID, March 23). It’s unclear if this most recent development will impact the timeline for filing and, ultimately, its chances of authorization.

The Canadian government, which has just authorized the AZ vaccine, came out Tuesday saying it continues to support use of the shot in its vaccination efforts despite the NIH’s concerns raised around the company’s press release. — James Miessler