LONDON: Advanced trials of the coronavirus (COVID-19) vaccine developed by a team at Oxford University in partnership with pharmaceutical giant AstraZeneca are set to resume after being halted over fears that subjects might suffer adverse side effects.
AstraZeneca stopped trials in the UK, US, South Africa and Brazil after a patient was hospitalized with suspected transverse myelitis (TM), an inflammatory condition affecting the spinal cord. However, the patient in question is set to be released from hospital after examinations suggested she did not have the condition.
The company’s CEO Pascal Soriot said the delay had been “temporary” and that a panel of experts would investigate the situation.
“This is a routine action which has to happen whenever there is a potentially unexplained illness in one of the trials ... in large clinical trials, illnesses will happen by chance and must be independently reviewed,” an AstraZeneca spokesperson said.
Pauses in drug and vaccine trials are not unusual, and this is the second time the Oxford vaccine has had to be delayed because of unexplained illness. In July, AstraZeneca confirmed, trials were temporarily set back after a patient was diagnosed with multiple sclerosis, in a development unrelated to the vaccine.
Early phases of the trial, including around 1,000 volunteers in the UK, have seen several side effects among subjects, including fatigue and headaches.
Robin Shattock, professor of mucosal infection and immunity at Imperial College London, said: “I think this is pretty normal — if it’s shown not to be related to the vaccine it will restart in a couple of days and it will be seen as a storm in a teacup. Even if associated with the vaccine they may be allowed to proceed but with caution.”
UK Health Secretary Matt Hancock told British radio station LBC: “This is a normal part of a vaccine development that, when you find a problem, the system is paused while you investigate that particular problem. What it underlines is that we won’t bring forward a vaccine unless it is safe, no matter how enthusiastic I am for a vaccine.”
The Oxford project had been considered the frontrunner in the global quest to discover a viable vaccine for COVID-19, but some analysts now say that the delay could hand the initiative to a rival team.
US biotech firm Moderna and German company Biontech, in partnership with the US drugmaker Pfizer, are among those developing vaccines that have also reached the advanced trial stage.
Analysts at JP Morgan Cazenove, the US stockbroker, said: “While it is true that a delay could increase Moderna’s and Biontech’s odds of winning the so-called ‘race to the COVID-19 vaccine finish line,’ we think this adds little fundamental value, as a vaccine’s ultimate clinical profile should trump any first-mover advantage in what we still anticipate to be a competitive market.”
Dr Siu Ping Lam, the director of vaccine licensing at the UK Medicines and Healthcare Products Regulatory Agency, said: “We are urgently reviewing all the information and actively engaging with the researchers to determine whether the trial should restart as quickly as possible. Vaccine safety is of paramount importance and we continually monitor the safety of vaccines to ensure that the benefits outweigh any potential risks.”
Soriot confirmed, meanwhile, that the trial subject suspected of developing TM, a woman from the UK, had been given the Oxford vaccine and not a placebo as part of the trial.
Ian Jones, professor of virology at the University of Reading, said: “It’s inflammation of nervous tissue which can be caused by a number of agents, one of which is viruses. The stoppage might be because the symptoms are plausibly linked to the vaccine, although it could be something else.”