Clinical trials for the COVID-19 vaccine were resumed following the death of a participant; the vaccine’s genetic programming was validated by the University of Bristol; and the Director of the Jenner Institute, Adrian Hill, expressed hope that some vulnerable groups could receive the vaccine by Christmas.
Global trials were “voluntarily paused” on 6th September after a volunteer developed transverse myelitis, a condition which causes inflammation of the spinal cord. While trials resumed in Brazil, South Africa, Japan and the United Kingdom resumed throughout September, the Food and Drug Administration in the United States refused to allow the trial to continue until they were convinced the volunteer’s illness was not caused by the vaccine.
30,000 volunteers are participating in trials for the Oxford vaccine in the United States, with a further 20,000 volunteers globally. It is hoped that the trial’s large sample size will mean that a vaccine can be developed more quickly, and that herd immunity can be induced safely within the global population.
The chief investigator of the trial at Oxford University, Professor Andrew Pollard, said: “We are very pleased the FDA has reached the same conclusion as the other regulators of the clinical trial sites around the world, declaring the trial safe to proceed in the USA…We will continue to adhere to our rigorous safety processes while moving as quickly as possible so we can start protecting people around the world against this terrible virus as soon as possible.”
The death of a trial volunteer in Brazil was also investigated. However, the volunteer had not received the vaccine, only the placebo, so it was not deemed to be connected to the trial.
This news comes in the same week that a team at Bristol University have independently confirmed that the Oxford vaccine genetic programming works as its developers intended. The validation goes “significantly above and beyond any regulatory requirements anywhere in the world”.
The Oxford vaccine works by co-opting the ability of viruses to introduce their genetic material into a cell, causing it to assemble more viruses. A harmless chimpanzee adenovirus is used to introduce a sequence of DNA from a SARS-CoV-2 virus which only produces the parts of a virus recognised by the body’s immune system. Scientists hope that this reduces the risk of a person becoming ill after receiving the vaccine. The research from Bristol University confirms that this process works, and that the required viral proteins are produced.
Professor Adrian Hill, who is leading the development process, has expressed hope that some high risk groups, such as the elderly, could receive doses of the vaccine by the end of the year. In a statement to members and alumni of Magdalen college he stressed that “the initial licence would be for emergency use, not full approval”.
Such approval would be dependent on safety data, including that collected from trials in the United States. The pause in the trials in the US has shown that the process of developing new vaccines is rarely straightforward, and so it is difficult to predict exactly when one may be approved for the general population.
Image credit: Amir Pichhadze