After disclosing promising results from its COVID-19 vaccine trial earlier this week, drug maker AstraZeneca is now facing tough questions from experts, especially after the company admitted a manufacturing error by a contractor.
The error came to light after AstraZeneca, which is developing the potential COVID-19 vaccine in partnership with Oxford University, revealed different efficacy results from two different dose regimes.
In the two different dose regimens vaccine efficacy was 90 per cent in one and 62 per cent in the other. The higher efficacy regime used a halved first dose and standard second dose. Two full doses showed lower efficacy.
AstraZeneca made a key “mistake” in the vaccine dosage received by some volunteers only after disclosing the preliminary results, according to a report in the New York Times on Wednesday. This raised questions about whether the vaccine’s efficacy rate
derived from the interim analysis of the Phase 3 trial will hold up under additional testing, said the report. Officials in the US have already pointed out that the results were not clear, said the NYT report.
In a series of tweets on Wednesday, Natalie Dean, Assistant Professor of Biostatistics at the University of Florida, who also specialises in vaccine trial design, said that “Astrazeneca/Oxford get a poor grade for transparency and rigor when it comes to the vaccine trial results they have
reported.” “This is not like Pfizer or Moderna where we had the protocols in advance and a pre-specified primary analysis was reported,” she said.