by Madeeha Khan
The coronavirus pandemic has been spreading at a high rate. Experts like Andrew Pollard, Director of the Oxford Vaccine Group and Chief Investigator of the COVID-19 trials has been at the forefront of the vaccine development research. This vaccine is called ChAdOx1 nCoV-19. It is said to be safe and can induce promising immune responses. It will be tested in India among other countries and around 1,500 healthy volunteers are expected to enrol.
The Oxford researchers announced on 20th July that the clinical trials in the UK have shown that this vaccine is safe and it generates strong immune responses against COVID-19. It involved around 1000 people aged 18 to 55 and the vaccine triggered their dual immune response that lasted for 2 months. It also proves equally effective in larger trials.
Oxford and AstraZeneca are collaborating with partners globally. AstraZeneca is a UK based global biopharmaceutical company. Rajeev Dhere, Executive Director of Serum Institute said, “We hope clinical trials with this vaccine can start in India by early August.” Serum Institute exports multiple vaccines worldwide and plans to mass-produce the COVID-19 vaccine.
The vaccine is made of a genetically choreographed virus that causes the common cold in chimpanzees. It has been majorly modified so it doesn’t cause infection in people and is made to look like coronavirus. Coronavirus uses the spike protein in the body to invade the cells. The scientist did this by transferring the genetic instructions to the vaccine they were developing. It will prepare your immune system to learn how to fight COVID-19. Antibodies and T cell help in fighting the virus. Antibodies are small proteins made by the immune system that sticks on the virus’s surface. Whereas T cells are white blood cells that help coordinate with the immune system and spot which body cells have been infected and then destroy them. Neutralising antibodies can disable the virus. Almost all the vaccines induce both.
The Oxford and AstraZeneca have been working together for the development of large scale manufacture and distribution of the vaccine. They’ve promised to supply around 2 billion doses of this vaccine with the help of global partnership and the commitment to the Serum Institute. Experts say that it is important to test these vaccines in various parts of the globe because people with different immunity levels would react differently to it. Also, the vaccines use an adenovirus and components of SARS-CoV-2 to generate immunity against COVID-19. Pre-existing immunity levels to adenovirus vary from 80% in India to 60% in South Africa and around 30% in the U.S.
There is a lot of diversity in the vaccine design strategies of different people because nobody knows which candidate will protect people from COVID-19. In India, trials of a candidate vaccine made by the Hyderabad based Bharat Biotech and another from the Ahmedabad based Zydus Cadila began in earlier July. As of 15th July, 23 candidate vaccines are in human trials and 140 are still undergoing lab treatments worldwide.
Prof. Andrew Pollard, in an interview with BBC, said, “We’re really pleased with the results published today as we’re seeing both neutralising antibodies and T cells. They are extremely promising and we believe the type of response that may be associated with protection. But the key question everyone wants to know is, does the vaccine work, does it offer protection… and we’re in a waiting game.”
However, studies have shown that 90% of people developed neutralising antibodies in one dose but 10 people were given 2 doses and then they produced neutralising antibodies. There are a few side effects of the vaccine like a headache or fever which can be managed by giving paracetamol. Hoping that this vaccine may be a solution to this novel coronavirus.