New Delhi: Corbevax — one of the two new vaccines to be added to India’s Covid-19 vaccination programme — will “make up for lost time” in the race to immunise millions in low- and middle-income countries who haven’t had access to any vaccine, Dr Peter Hotez, co-developer of Corbevax, told ThePrint.
“I think it was a science policy failure not to take a step back and have that situational awareness to say, we also need some straightforward vaccines using older technologies that could be administered to people across the world right now,” Hotez said, referring to the front-running mRNA and adenovirus vaccines that secured early emergency-use authorisation during the beginning of the pandemic in the United States.
For example, Pfizer and Moderna vaccines are mRNA vaccines, while Sputnik and Covishield are adenovirus vaccines.
“If we had greater support, even a fraction of the support that, say, Moderna got, who knows, maybe the world would have been vaccinated by now, and we never would have seen or heard of Omicron in the first place,” he added.
Hotez is dean of the National School of Tropical Medicine at Baylor College of Medicine, Texas, and director, Center for Vaccine Development at the Texas Children’s Hospital, with decades of vaccine research under his belt. He, along with Dr Maria Elena Bottazzi — his colleague at Baylor College — modified an earlier vaccine they were working on for the Severe Acute Respiratory Syndrome (SARS) and the Middle East Respiratory Syndrome (MERS) to suit Covid-19.
Hotez and Bottazzi have decided to waive the patent on their technology transfer in the spirit of “decolonisation”.
Last month, the central government had cleared two new Covid vaccines — Corbevax and Covovax (developed by Novavax and the Coalition for Epidemic Preparedness Innovations) — aside from the previously approved Serum Institute’s Covishield, Bharat Biotech’s Covaxin, Zydus Cadila’s ZyCoV-D, Russia’s Sputnik V and the US-made Moderna, and Johnson and Johnson.
The Union Ministry of Health & Family Affairs had announced on 30 December 2021 that approximately 90 per cent of India’s population had been vaccinated with the first dose, according to an ANI report.
Also Read: India’s looking at Corbevax, others. World also needs to move beyond mRNA vaccines
How Corbevax works
Corbevax is a recombinant protein subunit vaccine, which means it uses a particular protein of the virus — in the case of Covid-19, the receptor binding domain (RBD) of the spike protein. The gene for the protein is then inserted into a microbe like yeast, which then replicates the protein.
This protein is paired with an adjuvant — a substance that enhances the immune response — to form the vaccine. Once injected, the body responds to the presence of the spike protein and launches an immune response.
This technology is easily accessible, scalable, and has been used to make vaccines for decades. The commonly available Hepatitis B vaccine also uses this technology.
Hyderabad-based company Biological E — another co-developer that is manufacturing Corbevax in India — has already taken an order of 300 million doses from the Indian government.
“The distribution plan is very much under Biological E, they are working now with the Indian regulators, the Drugs Controller General of India and the Indian government, to plan where to ship doses of the vaccine and how to begin that process,” Hotez said.
Efficacy against Omicron, suitability for children being tested
Over the past two weeks, India has seen a sharp rise in Covid-19 cases. According to the health ministry website, there were 8,21,446 active cases in the country as of Tuesday, when 97,827 new cases were recorded.
The Indian SARS-CoV-2 Genomics Consortium (INSACOG) — a consortium under the central government that monitors genomic variations of the coronavirus — has said that the Omicron variant of the coronavirus is fast replacing the previously dominant Delta variant.
Hotez said Corbevax’s efficacy is currently being tested against the Omicron variant.
“We’ve been testing the vaccine against a wide variety of variants and it is holding up very well, better than most vaccines against the Beta variant, the Delta variant. We do not yet have the data specifically for Omicron,” he added. “That should be forthcoming. But the hope is that since the vaccine is standing up so well with Delta and Beta, that it should have protective ability against Omicron.”
With Covid-19 spreading rapidly in the country, the central government has allowed “precautionary” third doses for healthcare workers and senior citizens with comorbidities.
“Boosters have been very fundamental to protection against both Delta and Omicron here in the US,” Hotez said, adding that most Covid-19 vaccines currently in use in India will likely require a booster dose.
Hotez also said the vaccine would be suitable for children: “I’m optimistic it could be a very important vaccine for children because of the safety profile. Paediatric studies are underway.”
‘Need more balance in vaccine production ecosystems’
Hotez has been extremely vocal about vaccine inequity during interviews as well as on his social media handles, and said the patent for Corbevax was waived in the spirit of “decolonisation”.
“I think part of the problem (of vaccine inequity) is that we’re too dependent on multi-national pharmaceutical companies,” Hotez said.
“There needs to be more balance in the vaccine production ecosystems between the multi-nationals, the group that calls itself the Developing Countries Vaccine Manufacturers Network, and some of the academic organisations. That will create a more robust system for fairness and global vaccine equity.”
(Edited by Gitanjali Das)
Also Read: How Corbevax and Covovax, the two vaccines newly approved in India, fight Covid