AstraZeneca Unveils COVID-19 Vaccine Candidate Trial Protocol

AstraZeneca has released the trial protocols for the late-stage study of its coronavirus vaccine candidate, AZD1222, amid mounting calls for transparency as its investigation into an adverse event continues.

According to the published protocol, the phase 3 trial has set a bar of 50 percent efficacy for the vaccine candidate, the same percentage the FDA has said it expects COVID-19 vaccines to meet. The protocol also mandates an interim efficacy analysis, an evaluation of data done before data collection has concluded, after 75 participants have become infected with coronavirus.

“A statistically significant finding at the interim analysis will not be considered a reason to stop the study, but instead will be interpreted as early assessment of efficacy,” the protocol says.

It is not known if AZ plans to file for regulatory approval or Emergency Use Authorization if the trial’s interim efficacy analysis shows the vaccine meets the effectiveness threshold. The company did not respond to a request for comment.

The drugmaker, the third to publish the workings of its vaccine trial after Moderna and Pfizer, came under scrutiny after a UK participant in its phase 3 vaccine trial experienced a serious adverse event, raising concerns about the safety of its candidate.

The National Institutes of Health (NIH) has launched its own investigation and urged the UK drugmaker to be more open about the potential side effect (DID, Sept. 16).

While the trial protocol does not shed more light on the safety issue, it’s a step toward the increased COVID-19 vaccine trial transparency Democrat lawmakers recently clamored for in a letter to nine companies developing promising vaccine candidates, including AstraZeneca (DID, Sept. 16). — James Miessler