A COVID-19 candidate vaccine being tested on South Africans has been halted after one person in the United Kingdom developed a serious neurological problem after receiving the vaccine.
AstraZeneca is the British Swedish multinational pharmaceutical and biopharmaceutical company developing the vaccine. It is headquartered in Cambridge, England.
AstraZeneca is running several large trials of its candidate vaccine, known as AZD1222, around the world, including in South Africa, the United States and the United Kingdom.
The company said it is investigating whether the neurological problem experienced by a patient in the United Kingdom is an isolated case or has been experienced by others. It will also try to determine whether the problem was caused by the vaccine or something else.
American scientists said on Wednesday that the result of that investigation would determine whether the trial is stopped permanently or temporary.
They argued that if the female volunteer’s illness is considered the result of the vaccine, the company of the Data Safety Monitoring Board could decide that AstraZeneca’s candidate vaccine, AZD1222, isn’t safe enough to give to large numbers of people.
USA Today reported that based on technology developed by Oxford University, the vaccine uses a chimpanzee virus to deliver a bit of protein normally found on the outside of the SARS-CoV-2 virus that causes COVID-19. It said once a person has received the vaccine, their body will be primed to fight off the SARS-CoV-2 virus if exposed.
The publication added that “in the 1970s, a flu vaccine was connected to cases of a rare neurological condition called Guillain-Barré syndrome, although it was never clear whether the vaccine or the flu virus caused the syndrome.”
Viral infections, including COVID-19, have been known to cause rare neurological conditions, it added.
Not all vaccine trials are successful. According to a 2018 study, only about 25% of vaccines that enter human testing end up receiving approval and being marketed to the public,.
With many pharmaceutical companies racing to find a vaccine to the novel coronavirus, a respiratory disease that has killed close to 900,000 people around the world, including over 30,000 in Africa, many said the halt should serve as a warning to those may be trying to rush a vaccine.
The World Health Organization Director General Dr. Tedros Adhanom Ghebreyesus said on September 4 the WHO ‘will not endorse a vaccine that is not effective and safe’.
Speaking at his regular press briefing in Geneva, Dr. Tedros Adhanom Ghebreyesus said there are “a number of promising” vaccines, but they will only be used on people if they are effective and and safe.
He said the WHO has a track record of using effective and safe vaccines that have changed the world in the past decades and years.
Dr. Tedros Adhanom Ghebreyesus said early in the year that the vaccine trials would be applied equally and not test the bad ones on Africans first as had been cases in the past.