EMA review of AZ’s COVID-19 vaccine imminent; report

The EU regulator is poised to start a review of AstraZeneca and Oxford University’s COVID-19 vaccine, but the FDA is widening its investigation into the shot’s safety, according to reports citing people close to the project.

According to Bloomberg, the EMA could announce the start of a “rolling review” of AZD1222 – also known as ChAdOx1 – as early as this week, which would put the vaccine firmly on course to be the first approved for use in Europe.

Reuters meanwhile suggests that the vaccine could be subjected to further delays in the US as the FDA has started sifting through data from earlier trials of vaccines developed by the same scientific team to look for safety signals.

The US arm of a phase 3 trial of AZD1222 has remained on a clinical hold since 6 September, after a subject in the UK was feared to have developed a neurological side effect after receiving the vaccine, but was swiftly restarted elsewhere.

AZ has denied reports that the patient developed transverse myelitis, an inflammation of the spinal cord that has been observed after viral infections as well as some vaccines, but hasn’t revealed the nature of the illness, citing patient confidentiality reasons.

Meanwhile, there have been some inconsistencies between the company’s reporting on the case and that of Oxford University which reportedly prompted a US National Institutes of Health investigation into the incident.

The Reuters report suggests that the FDA’s decision to widen its probe is borne out of caution rather than any strong belief that the vaccine has side effects. However, it says the probe has been made more complicated because data provided by trial investigators is in a different format to that usually required by the agency.

Safety is always of paramount importance in new medicine development, but particularly so with vaccines as they are administered to healthy people. Severe symptoms are also uncommon in people who are infected with the SARS-CoV-2 virus making the risk-benefit calculations even more challenging.

AZ limited its comments on the situation to a brief statement that it is “continuing to work with the FDA to facilitate review of the information needed to make a decision regarding resumption of the US trial.”

According to the World Health Organization (WHO), AZ’s vaccine is already the furthest ahead in a list of 40 vaccines in clinical trials for COVID-19, and that position will be consolidated if the rumour of a rolling review by the EMA is accurate.

Earlier this year, the EMA’s head of vaccines – Marco Cavaleri – suggested that the first approval of a COVID-19 vaccine could come in the EU before the end of 2020.