The race to find a cure for the novel Coronavirus is on, with researchers exploring ways to see if they can fast track the vaccine development process, which can save millions of lives. For hundreds of years, scientists have been using human challenge trials to test the effectiveness of vaccines such as influenza, smallpox, malaria, typhoid, dengue fever and cholera.
Vaccine development is a long, complex process involving multiple stages of testing.
Firstly, a vaccine candidate is tested on animals to see if it’s safe and whether it triggers an immune response. The experimental vaccine is then tested on a small group of humans for safety and immune response.
If the vaccine results are encouraging, a Phase 2 trial is carried out on a larger, more representative population of several hundred subjects.
The Phase 3 clinical trials are the longest and involve thousands of participants, evaluating the effectiveness of the vaccine. Here, researchers look at various aspects such as differences in infection risk and side effects between those receiving the vaccine and those administered a placebo – before a vaccine is considered safe enough for regulators to approve for widespread use. This is important because the hope is to find a vaccine that reduces the risk of infection as well as causes no severe side effects. So, the whole process can be both complex and long.
However, in the case of human challenge trials, all study participants are deliberately exposed to the pathogen under highly controlled conditions.
Dr Vikram, a doctor and scientist in one of the topmost University College Hospitals in London, is the son of Ritha Talaulikar and Dr Vijay Talaulikar, senior obstetrician and gynecologist, who served Goa for 40 years before retiring in 2009. Vikram is now settled in UK with his wife Anuradha and daughter Varada.
Dr Vikram is a specialist in reproductive medicine at University College London Hospital. He feels that it’s very important to set up and complete clinical trials, which can lead to the development of a vaccine or medication that would be effective in preventing the infection or reducing the severity of the illness.
Dr Vikram explains about the vaccine trial and safety measures provided to him. “The COV002 vaccine trial is one of such trial which is testing how well a new vaccine developed by the Oxford Vaccine Group works against COVID-19. The trial is being performed with robust monitoring and safety standards in place. From the starting point of consenting for the trial until completion, there are various check points where symptoms, swabs, blood tests will be carried out to check for signs of infection, any side effects and changes in serology (blood parameters). As a doctor who comes into contact with patients, robust PPE procedures have been put into place in clinical settings to avid risk of any infection transmission.”
He stated that the vaccine being tested currently is a weakened version of an adenovirus (common cold virus) from chimpanzees that has been genetically changed. To this virus, genes have been added which make proteins from the COVID-19 virus which play an essential role in infection pathway. “The hope is that body will develop an immune response to this spike glycoprotein which can help stop virus from entering the human cells. It is difficult to predict accurately at this stage but if sufficient recruitment happens and the data is promising, we may see the vaccine ready for use before the end of this year,” he added.
Vikram stresses on continuing with social distancing, wearing of face masks in public and enclosed spaces, as well as the use of hand wash and sanitizers, which goes a long way in preventing the disease.
