Dr. Soumya Swaminathan, the World Health Organization's chief scientist, said the United Nations health agency wasn't overly concerned by the pause in the Oxford and AstraZeneca vaccine trial, describing it as "a wake-up call" to the global community about the inevitable ups and downs of medical research.
AstraZeneca announced on Wednesday it had "voluntarily paused" its trial of the vaccine developed alongside Oxford University after the volunteer developed an unexplained illness.
At the same time, the suspension of trials clearly showed the fallacy of the approach, when entire countries exclusively rely on novel and untested platforms when choosing a vaccine.
"We must all hope that there are no future events and that the vaccine proves both safe and effective".
In an email to NPR Saturday, an AstraZeneca spokesperson said "the company will continue to work with health authorities across the world, including the FDA, and be guided as to when other clinical trials can resume".
The statement said the UK Medicines Health Regulatory Authority approved trials to resume after an independent review of data "triggered a voluntary pause" on September 6.
The Oxford vaccine is still subject to trials, but it has reached advanced stages in many countries and the final phase of trials in Brazil.
During the study, participants who received the vaccine had detectable neutralising antibodies, which have been suggested by researchers as important for protection, and these responses were strongest after a booster dose, with 100 per cent of participants' blood having neutralising activity against the coronavirus.
The Oxford clinical trials are the third Phase 3 trials to begin in the U.S.
He said the trial was going well, but unfortunately a few days ago the news came out that it had been halted because one of the recipients developed a case of transverse myelitis, which is an inflammatory condition of the spinal cord which causes sensory and motor deficits.
The vaccine is in late-stage clinical trials in the United States, Britain, Brazil and South Africa and additional trials are planned in Japan and Russian Federation.
Temporary holds on large medical studies are not uncommon, and looking into any unexpected reactions is a mandatory part of safety testing.
AstraZeneca has already said it would work with health authorities around the world to supply around three billion doses of the vaccine "equitably", to countries including Russia, China, the USA and Brazil.
However, WHO's Chief Scientist Soumya Swaminathan said there's not much to be discouraged about.
The report follows others in which a separate Chinese company, Sinovac Biotech, reported at a trade fair in Beijing last week that it, too, had injected between 2,000 and 3,000 of its employees and family members with its experimental vaccine.