With nearly 15,000 dead worldwide of Covid-19, developing a vaccine against it has become part of the emergency efforts undertaken by nations. Anti-Covid-19 drug research is on at over 60 pharma companies, biotech firms, university research centres, etc, including the private-sector, Serum Institute of India.
At least two candidates have already entered the clinical evaluation stage, according to the World Health Organization (WHO). China-based CanSino Biologics and the Beijing Institute of Biotechnology have collaborated on a non-replicating viral vector vaccine that is to be tested on 108 human volunteers aged between 18 and 60.
The other is mRNA (messenger RNA that is involved in protein production within a cell) 1273, developed by the National Institute of Allergy and Infectious Diseases under the US National Institutes of Health, and to be manufactured by Moderna TX. The trial has begun in Seattle, US, on 45 human volunteers in three groups. The trials involve two doses of the vaccine candidate being administered, the first on day 1 and the second on day 29, and the subjects will be followed through 12 months after the second dose.
The mRNA in the vaccine will code for the Spike protein of SARS CoV-2 which aids the virus's entry into the host cell. With the clinical trial having begun in mid-March, the results of the trials for the primary objective - safety and reactogenicity - vaccine spurring expected 'adverse' reactions, mostly due to immunological responses - will be available around the same time in 2021, while the results on the secondary objective, the levels of immunogenicity of the vaccine (its ability to provoke an immune response) will be available around May 12-15.
WHO reports 42 other vaccine candidates that are in the pre-clinical stage at the moment. While the Serum Institute of India is working on live, attenuated (virulence drastically reduced) strain of SARS CoV-2, in collaboration with US-based Codagenix, another Indian pharma major, Zydus Cadila, is working on two vaccine candidates, one based on DNA plasmid (in which a genetically engineered strand of DNA is used to code for the antigen to which an immunological response is being sought) and the other based on a replicating measles virus vector (in which a weakened measles virus is used to deliver genetic material from the SARS CoV-2 virus that codes for the latter's surface proteins to stimulate immunological response). There are 19 universities and other research bodies, including Oxford University, Imperial College London, Institut Pasteur (10 of whose researchers have won the medicine Nobel, including Luc Montagnier and Françoise Barré-Sinoussi for the discovery of HIV).
Given the genomic details of the SARS CoV-2 shared by China only in late January, vaccine candidates have entered clinical trials in record short time, though a successful vaccine may take some time. The Coalition for Epidemic Preparedness Innovations (CEPI), launched in 2017, with funding from the Bill and Melinda Gates Foundation, the Wellcome Trust and a host of nations-India also joined shortly after the initiative was launched - has committed $100 million to vaccine research while the US government is giving the National Institutes of health $836 million for coronavirus research, apart from $2.2 billion for others on Covid-19 vaccines, test kits and therapeutics.