AstraZeneca and the University of Oxford have defended their coronavirus vaccine from critics of its clinical trials.
The criticisms were about the results and methods applied to phase three vaccine trials. AstraZeneca and the University of Oxford said they adhered to the “highest standards” and that “additional analysis will be conducted.”
AstraZeneca shares dropped by around 6% this week after questions about its vaccine candidate rose.
Chief of the White House’s Operation Warp Speed, Moncef Slaoui, and other authorities in the U.S. were particularly concerned about the age group of participants. They said that 90% efficacy was only shown for the lowest risk group, which had 2,741 people below the age of 55. The group whose results showed 62% effectiveness numbered 8,895.
AstraZeneca cited the monitoring of the study held by the external Data Safety Monitoring Board (DSMB) and the fact that the data shared on Monday was based on interim results and that more data would follow.
“The studies were conducted to the highest standards,” a spokesperson for AstraZeneca told CNBC on Thursday. “An independent DSMB safety monitoring committee oversees the studies to ensure safety and quality. The DSMB determined that the analysis met its primary endpoint showing protection from COVID-19 occurring 14 days or more after receiving two doses of the vaccine.”
“More data will continue to accumulate and additional analysis will be conducted refining the efficacy reading and establishing the duration of protection,” the spokesperson said.
Meanwhile, the University of Oxford mentioned the discrepancy between dosage allotments. It explained that an initial over-estimation of the dose of the new Covid-19 vaccine batches had resulted “in a half dose of the vaccine being administered as the first dose” due to a “difference in the manufacturing process.”
“The methods for measuring the concentration are now established and we can ensure that all batches of vaccine are now equivalent,” it added.
Analysts from U.S.-based health care and biotech investment bank SVB Leerink said: “We believe that this product will never be licensed in the U.S.”
“This belief is based on the design of the company’s pivotal trials which does not appear to match the FDA’s requirements for the representation of minorities, severe cases, previously infected individuals and elderly and other increase risk populations,” the analysis said.
But a spokesperson at AstraZeneca pointed out that the results were interim and that more data was to be gathered and more analysis to be held
John LaMattina, a former president of Pfizer Global R&D, tweeted on Tuesday: “Hard to believe that the FDA will issue an EUA for a vaccine whose optimal dose has only been given to 2,300 people. More data for this dosing regiment will be needed.” Slaoui was previously on the board at Moderna and also worked at GlaxoSmithKline.
Meanwhile, Jefferies analysts said that in terms of storage, affordability, and distribution, the AstraZeneca-Oxford vaccine seems to have an advantage.
AstraZeneca pointed out that its coronavirus vaccine can be stored, shipped, and handled at normal refrigerated conditions for at least six months and administered within existing healthcare settings. It has also promised to ship the vaccine at no profit “for the duration of the pandemic.”
