Oxford University started human clinical trials for its potential COVID-19 vaccine in Brazil, one of the worst-hit countries and current epicentre, over the last weekend. Vaccine sponsor Lemann Foundation said in a statement that the trials will be performed on 2,000 health workers volunteers in Sao Paulo, Brazil’s most populous city, and 1,000 people in Rio de Janeiro.
Sarah Gilbert, the lead researcher of the vaccine development programme, had reportedly told a virtual conference on April 17 that her team is confident about the efficacy of ChAdOx1 vaccine. The team had already been working on a plan for an unknown disease, named Disease X, which would have caused a pandemic.
The vaccine is made of a weakened and modified version of adenovirus (a common cold virus) that causes infections in chimpanzees. The team of researchers extracted the genes for the spike protein on the surface of the coronavirus. When the vaccine is injected into a body, the vaccine enters cells and start producing coronavirus spike protein.
The spike in protein prompts the immune system to produce antibodies and trigger T-cells to destroy the infected cells. If the individual encounters the novel coronavirus, the antibodies and T-cells are activated to fight the virus. Oxford Univesity said in a separate statement that vaccines made from the ChAdOx1 virus have been given to more than 320 people to date and have been shown to be safe with temporary side effects, such as mild fever, headache or a sore arm.
Brazilian Health Regulatory Agency (Anvisa) approved the trials on June 2 and the Lemann Foundation will cover the costs of all the necessary medical infrastructure and equipment. The volunteers will receive the vaccine and will be left exposed to the virus normally in their day-to-day work. Dr Lily Yin Weckx, a principal investigator of the study and coordinator of the program in Brazil, said in a statement that the most important thing is to carry out these trials at a time when the epidemiological curve is still rising and the results may be more decisive.