AstraZeneca (AZ) and Johnson & Johnson (J&J) are both set to resume their respective phase 3 COVID-19 vaccine trials following separate trial pauses.
AZ paused its phase 3 trial of its Oxford University-partnered COVID-19 vaccine candidate, AZD1222, on 6 September after a participant in the UK-based trial experienced a serious adverse event.
According to The New York Times, the volunteer in AZ’s trial developed transverse myelitis, a condition which is associated with viral infection and affects the spinal cord.
Although the trial has already resumed in the UK, Brazil, South Africa and Japan, the US-arm remained on pause after the Food and Drug Administration (FDA) broadened its investigation into the event.
After reviewing all of the safety data from the global trials, the FDA authorised the restart of the US arm of the trial on Friday.
In a statement, AZ said that the participant illness is not uncommon in large scale vaccine trials, adding that every case must be evaluated to ensure the safety of the assessment.
The company added that it is expecting results from the late-stage trials of AZD1222 later this year, although it said this is dependent on the rate of COVID-19 infection in the communities where the clinical trials are being conducted.
“The restart of clinical trials across the world is great news as it allows us to continue our efforts to develop this vaccine to help defeat this terrible pandemic,” said Pascal Soriot, chief executive officer of AZ.
“We should be reassured by the care taken by independent regulators to protect the public and ensure the vaccine is safe before it is approved for use,” he added.
In a separate announcement, J&J said that the Independent Data Safety Monitoring Board (DSMB) overseeing the pause of its phase 3 ENSEMBLE study recommended resuming trial recruitment.
Earlier this month, J&J voluntarily paused the trial after a participant in the large-scale trial developed an unexplained illness.
However, based on the information gathered to date and the input of independent experts, J&J said that it has found no evidence that its vaccine candidate caused the event.
Following consultation with the FDA, J&J is now preparing to resume the US-based trial, including submissions for approval by the Institutional Review Boards. The company added that discussions with other global regulators to resume the clinical trial programme are currently progressing.
J&J did not reveal if the participant who experienced the serious medical event had received the COVID-19 vaccine or placebo.