Corbevax, a new vaccine against COVID-19, may have better success as a candidate for vaccine equity because it carries no patents, relies on long-established recombinant technology for manufacture and has the support of the US and Indian governments, its makers and health experts say.
The vaccine already has emergency use approval in India and the Hyderabad-based collaborator, Biological E Limited, is set to produce 100 million doses a month, starting February, according to a company spokesperson.
India's Biotechnology Industry Research Assistance Council (BIRAC) helped see Corbevax through the pre-clinical stage and the Phase III clinical studies and is expected to advocate early clearances from the WHO.
Mahima Datla, managing director of Biological E, says once WHO clearances come through, Biological E is confident that it can scale up manufacturing to deliver 300 million doses as promised to the Indian government and an additional one billion doses globally.
Corbevax's development owed mainly to a long-standing partnership to produce various vaccines between Biological E, the Texas Children's Hospital Center for Vaccine Development, and the Baylor College of Medicine in Houston, Texas.
Over the years, we worked together to produce vaccines that were of good quality and accessible around the world. Given this background, we could readily develop Corbevax as an effective and affordable vaccine against COVID-19."
Mahima Datla, Managing Director of Biological E
Srinath Reddy, president of the Public Health Foundation of India, tells SciDev.Net that "Corbevax is easy to manufacture and distribute because the recombinant technology used has been employed for decades to produce, for example, the Hepatitis-B vaccine".
Unlike mRNA and several other vaccines which require extremely low cold chains, Corbevax can be stored and transported at 2—8 degree Celsius, allowing countries with limited resources to store and distribute it, Reddy said. It could prove ideal for booster doses for which trials are now being conducted in India, he added.
Biological E affirmed that the vaccine was found to be safe, well-tolerated and immunogenic [capable of building immunity] following the completion of phase III clinical trials involving more than 3,000 subjects between the ages of 18 and 80 at 33 sites across India.
Phase III studies showed Corbevax stimulating a better immune response than Covishield, a vaccine developed by Astra-Zeneca and the Oxford University, which is being manufactured in India and is the mainstay of the country's COVID-19 immunisation programme. It also had fewer adverse reactions.
Reddy expects Corbevax to be cheaper than most existing vaccines mainly because of the intellectual property rights waiver announced by its main co-creator, Peter Hotez, co-director of the Texas Children's Hospital Center for Vaccine Development and professor at the Baylor College of Medicine.
Hotez said in a tweet on 28 December: "We technology transferred our vaccine and helped in its co-development with Biological E with no patent and no strings attached. As a result, it should be the least expensive COVID vaccine available yet."
"This vaccine can be made locally all over the world, and we've now technology transferred our Texas Children's vaccine to producers in India, Indonesia, Bangladesh, Botswana. Our Texas Children's Center does not plan to make money on this, it's a gift to the world," Hotez also tweeted.
On 17 January, addressing the World Economic forum in Geneva, UN Secretary-General Antonio Guterres said the world was "nowhere near the targets" set by the WHO to vaccinate 40 per cent of people in all countries by end 2021 and 70 per cent by the middle of this year.
"Vaccination rates in high-income countries are - shamefully - seven times higher than in African countries," Guterres said. "We need vaccine equity, now. We need pharmaceutical companies to stand in solidarity with developing countries by sharing licenses, knowhow and technology so we can all find a way out of this pandemic."
Reddy said the world cannot wait any longer for developed countries to share licenses and resolve rivalries over patents. "It is far better to use time-tested and safety-proven technology — like that used for the creation of Corbevax — to immunise as many people as possible in the shortest possible time."
Corbevax, said Reddy, would be particularly useful for the global vaccination programme in the face of emerging COVID-19 variants such as Omicron, now sweeping across many countries, including India.
"We believe that this vaccine will address the needs of the world and help the global population fighting against the spread of COVID-19," the Ministry of Health and Family Welfare said in a statement.
Emergency use approval for Corbevax was granted in India on 28 December along with similar approval for Covovax, a subunit vaccine developed by the US-based Novovax, licensed to be manufactured by the Serum Institute of India.
Two other US vaccines already deployed in India are Moderna, which uses the genetic code of messenger RNA (mRNA) to prime the immune system to respond to COVID-19, and Johnson and Johnson, a single-dose adenovirus vector vaccine. Adenoviruses are common viruses that cause cold- or flu-like illness while vectors are inactivated viruses that can stimulate the immune system to generate antibodies.
A DNA vaccine produced by the Ahmedabad-based Zydus Cadila called ZyCoV-D does not need syringes but is administered with a needle-free applicator. DNA vaccines work by transferring a genetically modified blueprint of viral genes into small molecules of DNA or genetic material for injection.
With such an array of COVID-19 vaccines, India has already covered 90 per cent of its eligible population with a first dose and 65 per cent with a second dose.
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