Pharmaceutical giant AstraZeneca stood by the results of its US-based clinical trial on Tuesday, a day after the Data and Safety Monitoring Board (DSMB) expressed concern that the data from the trial may have been “outdated” and “incomplete.”
“The numbers published yesterday were based on a pre-specified interim analysis with a data cut-off of 17 February,” the company said in a statement.
“We have reviewed the preliminary assessment of the primary analysis and the results were consistent with the interim analysis. We are now completing the validation of the statistical analysis,” it added.
“We will immediately engage with the independent data safety monitoring board (DSMB) to share our primary analysis with the most up to date efficacy data. We intend to issue results of the primary analysis within 48 hours,” the statement concluded.
The DSMB is an independent expert group that sees trial data before the pharmaceutical companies, the doctors running the trials, or even the US Food and Drug Administration. They have the power to advise a company of positive interim findings or to halt a trial over safety concerns. That’s what happened to the AstraZeneca trial in September after a study participant developed neurological symptoms, for example.
More context: The DSMB had expressed concern over AstraZeneca’s announcements on its latest findings, according to a statement posted early Tuesday by the National Institute of Allergy and Infectious Diseases.
“Late Monday, the Data and Safety Monitoring Board (DSMB) notified NIAID, BARDA, and AstraZeneca that it was concerned by information released by AstraZeneca on initial data from its COVID-19 vaccine clinical trial,” the statement said.
“The DSMB expressed concern that AstraZeneca may have included outdated information from that trial, which may have provided an incomplete view of the efficacy data.
“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.”
Early Monday, AstraZeneca issued a press release saying its Covid-19 vaccine showed 79% efficacy against symptomatic disease and 100% efficacy against severe disease and hospitalization, citing long-awaited US trial data. The latter figure was based on five events in the placebo arm, NIAID director Dr. Anthony Fauci said during a coronavirus briefing Monday.
Last year, the National Institutes of Health appointed a common DSMB to monitor Covid-19 vaccine clinical trials that were being funded by the federal government — including AstraZeneca, Moderna and Johnson & Johnson. This DSMB has 10 to 15 members with specialties, including vaccine development, statistics and ethics.