The scientific community is on the hunt for developing a vaccine that might stop the COVID-19 pandemic. As on May 6, 203 potential vaccines are being developed and tested, and out of which, ten have progressed to the clinical stage. Who are the COVID-19 vaccine front-runners?
By Tariq Hashmat
With confirmed COVID-19 cases worldwide surpassing 3.8 million, scientists across the globe are pushing forward with efforts to develop vaccines to slow the spread of the pandemic and lessen the disease’s damage. California based Milken Institute, an independent economic think-tank, has developed a live trackerfor tracking the development of treatments and vaccines for COVID-19. As on May 6, the total count of potential treatments listed were 203 and potential vaccines in various development stage were 123. Out of which ten have progressed to the clinical stage.
With COVID-19 spreading exponentially, the importance of finding a vaccine is intensified. “No country is safe until we all are safe, for which an effective vaccine that is accessible to all is needed,” Dr. Poonam Khetrapal Singh, Regional Director, WHO South-East Asia toldvaccine manufacturers and regional national regulatory authorities from its South-East Asia Region.
Vaccines protect an individual from contracting the disease by providing acquired immunity. When vaccines show viruses to the immune system, the body’s immune system recognise them as an invader and learn how to fight them. Then if the body is ever exposed for real, it already knows what to do.
Public health specialist Dr. Sanjukta Sengupta says vaccination results in the formation of memory B cells which produce antibodies the moment they see the antigen, faster than natural immunity.
“This is primarily why one needs vaccination prior to infection,” said Dr. Sanjukta.
However, several steps must be completed before the COVID-19 vaccine can be developed on a large scale.
What goes into vaccine development?
All vaccines that are currently licensed and available have been made using a traditional development model that has the following five stages:
1. Discovery research involves lab-based investigations on finding ways to induce an immune response at a molecular level.
2. The pre-clinical stage involves testing in animals to assess the safety and suitability of potential vaccines for humans.
3. The clinical-stage involves testing potential vaccines in humans and has three phases of trials:
i) Phase I tests for safety and requires 10-50 people to take part in trials.
ii) Phase II understands the immune response and requires hundreds of people to take part.
iii) Phase III assesses if the vaccine candidate protects against the disease and requires thousands of people to take part in trials.
4. Regulatory review and approval involve submitting data and information to regulators for approval.
5. Manufacturing and delivery require specialist facilities that are highly regulated.
According to Wellcome Trust, the second-largest research charitable foundation in the world, following the traditional or conventional approach, vaccine development on average takes up to 10 years and investment between $200 and $500 million. But to develop the COVID-19 vaccine safely and quickly, this approach needs to change.
Accelerating the traditional model for COVID-19
For the development of the COVID-19 vaccine, Wellcome Trust advocates “a fast start with many steps executed in parallel” will have to be followed. Among many recommendations, Wellcome Trust focuses on having clinical trials at multiple global locations so as to have the best chance of finding a vaccine that’s safe for everyone.
In fact, global vaccine manufacturers have already taken the cue, and are positioning themselves to produce the billions of doses of COVID-19 vaccine the world critically needs.
How far have we come?
The world has joined hands to find a vaccine for COVID-19. Scientists and researchers across the globe are waiting for some major breakthroughs. Of the 123 potential candidates for the COVID-19 vaccine, ten have progressed to the clinical stage.
Ad5-nCOV, a non-replicating viral vector-based vaccine, was the first, and so far the only candidate vaccine for COVID-19 that has entered phase 2 clinical trials. Developed by China’s Academy of Military Medical Sciences and Hong Kong-based CanSino Biologics, the vaccine entered phase 2 trails on April 12, 2020.
China’s state-owned pharmaceutical giant Sinopharm is developingtwo inactivated vaccines, one through the Beijing Institute of Biological Products and the other through the Wuhan Institute of Biological Products.
The other two Beijing-based biopharmaceutical companies taking a lead are Sinovac and Shenzhen Geno-Immune Medical Institute. The companies are reported to be in different phases of vaccine development. However, the most closely watched candidate vaccine is being developed by Oxford University. The vaccine – ChAdOx1 was developed under three months by the University’s Jenner Institute. It uses a weakened strain of the common cold virus that causes infections in chimpanzees.
Currently in phase I of UK clinical trials, Serum Institute is also working closely with regulators of ChAdOx1 to start clinical trials in India. Also, the manufacturers are hopeful that the vaccine will be available by September 2020.
Where does India stand?
India is a major force in global vaccine production, accounting for 60 percent of all vaccines supplied to UNICEF in 2017. Currently, more than 30 COVID-19 vaccines are in various stages of development in India, and a few are expected to hit human trials in the next few months.
As part of its partnership with Oxford, Serum Institute of India, the world’s largest vaccine manufacturer aims to produce the ChAdOx1 vaccinein the magnitude of tens of millions per month even before the vaccine succeeds in its trials.
In addition, Serum is also involved in the development of a vaccine along with a New York-based biotech firm Codagenix.
Similarly, Gujarat-based pharmaceutical major Cadila Healthcare (Zydus Cadila) is working on two vaccines which are in the pre-clinical stage. The company is also working on developing rapid diagnostic kits and ramping up the production of hydroxychloroquine (HCQ).
Hyderabad-based Bharat Biotech is developing a vaccine called Coroflu. Its a one drop COVID-19 nasal vaccine and has shown to be safe and well-tolerated in humans, in Phase I and Phase II clinical trials. The product is part of an international collaboration of virologists at the University of Wisconsin-Madison and vaccine companies FluGenalong with Bharat Biotech.
Besides, these traditional powerhouses of vaccine making, small biotechs such as Gurgaon-based Premas Biotech, Pune-based Gennova Biopharmaceuticals, and Aurbindo Pharma’s subsidiary Auro Vaccines are also at various stages of vaccine development.
The Road Ahead
Professor of Vaccinology at Oxford University, Prof. Sarah Gilbert is part of the team working on the ChAdOx1 vaccine. In an interview, she acknowledged that the prospects of a workable vaccine are very good, however, uncertainty remains.
“Nobody can be absolutely sure if it’s possible to produce a successful vaccine, that’s why we have to do trials to find out,” said Prof. Sarah Gilbert in a press interview. She further added, “I think the prospects are very good but, clearly, it’s not completely certain.”
WHO’s Dr. Navid Nabarro has also flaggedthat the worst-case scenario, that no vaccine is ever developed, is also a possibility. The World Health Organisation has suggested that COVID-19 infections might resurge in several waves. More infections and more deaths are unfortunately feared.
However, Prof. Gilbert attributes these waves to the short-lived immunity in recovered patients who can then be reinfected. A lot is also at stake with manufacturers starting the production of under-trial vaccines.
Serum Institute of India’s CEO Adar Poonawalla saidthat his company “will spend some 300 million to 400 million rupees on making around 3-5 million doses per month.”
Meanwhile, world leaders have pledged more than $8bn to help develop a coronavirus vaccine and fund research into the diagnosis and treatment of the disease. Of the money raised, $4.4bn will go on vaccine development, some $2bn on the search for a treatment, and $1.6bn for producing tests, according to the statement of the European Union which hosted the online summit of the world leaders on May 4.
Even with all the financial commitments, it will take time to know which vaccine might eventually work and how well.
