Experts say that while the novel Coronavirus that hit planet earth in December 2019 created an unprecedented crisis for humankind the response to it by researchers, medical scientists and pharmaceutical companies in trying to discover a vaccine is also unprecedented. Under normal circumstances the process of discovering, testing and producing a vaccine takes from 5 years to 10 years thanks to the high failure rate associated with it. Therefore, the probability of having an effective COVID-19 vaccine within a year of the pandemic invasion is incredible news that speaks volumes about the non-stop efforts, dedication, round-the-clock supervision, utilization of special funds and global coordination put into it. As per the World Health Organization, at present there are nearly 200 vaccine candidates out of which 44 are in various stages of human clinical trials, and a few are about to be approved by the regulators. This would indeed be another crowing glory of the human quest should a safe and effective vaccine be really found and readied for public use in the coming months or even in the coming weeks.
China had been the first casualty of the pandemic, and therefore the Chinese researchers went all out for a vaccine. Their vaccine, called CoronaVac, was in fact approved for emergency use within the country in August 2020 itself, of course, without completing the Phase-3 clinical trials. Phase-2 human trial results showed that the vaccine produced antibodies that could neutralize 10 strains of the SARS-CoV-2 virus without any severe adverse reactions. This vaccine could be out for distribution anytime.
Russia became the first country to register a COVID-19 vaccine, Sputnik V, in August 2020 approving it for general use within the country, of course, without completing Phase-3 human trials. It has already claimed 92% efficacy, revised to 95% now. and the final trials are going on in several countries, Russia says the vaccine is being exported, including India.
Another major vaccine being jointly developed and tested by the US pharmaceutical giant Pfizer and Germany’s BioNTech is in the final clinical trials and it has claimed 95% efficacy based on interim data. The firms are likely to apply for emergency use authorization from the US regulators in mid-December 2020, and the vaccine could be out in the markets later next month subject to approval.
Moderna, a vaccine by the US Pharma, is also in the final stages, and it has already claimed that it is 94.5% effective based on interim data. It is likely to apply for emergency use authorization a few days later than Pfizer-BioNTech.
AstraZeneca, a vaccine developed by the Oxford University and co-developed by the Serum Institute of India (SII), has shown an average efficacy rate of 70% for Phase-3 trials with the likelihood of this going up to 90%. The vaccine has been proved to trigger an immune response in all age-groups, particularly and more significantly in the elderly group of below and above 70 years of age. The SII-developed vaccine Covishield is already priced at around USD 13 (1000 Rupees) per two doses, and the SII has been in the process of manufacturing 100 million doses within this year.
Janssen, the pharmaceutical wing of Johnson and Johnson, is also developing a vaccine that is in the final human trials phase after a pause in October 2020 due to an illness in one of the participants. With both singe-dose and two-dose regimens the final trials of the vaccine are being conducted worldwide with participants up to 60,000, and interim data shows that the vaccine induced a robust immune response and had been well tolerated.
Covaxin, a vaccine being developed by Bharat Biotech in India in collaboration with the Indian Council of Medical Research (ICMR), is also in the final phase clinical trials with the company saying that they expect at least a 60% efficacy rate in preventing the Coronavirus infection. Although the ICMR was hopeful of launching the vaccine by February 2021, Bharat Biotech sets a more practical launch date sometime in mid-2021.
Normally, a regulator approves a vaccine if it is found to be at least 50% safe and effective, and therefore, there should not be any difficulty for all these final-stage vaccines to get the authorization or approval. However, experts the world over insist that Phase-3 trial results do not necessarily indicate a safe and effective vaccine, because it is not possible for a vaccine to account for all kinds of induced side-effects across humanity whatever be the size of its volunteers. They say that it is critical to monitor the safety and efficacy of a vaccine even long after its roll-out, and there can be no certainty, for even years.
Prices and storage requirements of the rolled-out vaccines are among other concerns. Pfizer-BioNTech and Moderna are highly priced at USD 70 and USD 39 for the required two doses respectively. Besides, Pfizer-BioNTech requires storage at minus 70 degree Celsius while Moderna requires -19 C. Both of these factors make these vaccines difficult to obtain for the poor and developing countries. Hopefully, AstraZeneca, and its Indian counterpart Covishield, would be cheaper and it has been confirmed that it can be preserved in normal fridge temperatures. Sputnik V is also likely to be available at much lower prices, and Russians researchers have been engaged in testing a process of turning liquid Sputnik V into a dried white mass that can be stored at normal fridge temperatures of 2 C to 8 C and administered. This method is being termed as freeze-dried doses.
Willingness of the citizens across the globe to go for COVID-19 vaccination is another factor to be considered. At the moment the figures reveal low levels of willingness. However, once a vaccine is proved to be safe and effective the willingness is bound to improve. Besides, the people in the medical and essential service sectors are always the priorities. With the second wave of the pandemic gripping several countries of the world we have no option but to hope for the best, that one of the vaccines that can arrive anytime eventually proves to be safe and effective in the long run.



Source by Chinmay Chakravarty

Topics #coronavirus #covid-19 #vaccination #vaccine