As per the news reports in September 2020, Bharat Biotech is soon expected to move to phase II trials of ‘Covaxin’, its Covid-19 vaccine candidate. Besides, some other vaccine candidates include ‘Covishield’ by University of Oxford-AstraZeneca, ‘ZyCov-D’ by Zydus Cadila, RBD protein vaccine by Baylor College of Medicine-Biological E, HGC019 by Gennova Biopharmaceuticals-HDT, etc.
‘Covishield’ is one of the most closely watched candidates globally as it works on a mechanism that uses a weakened and non-replicating version of a common cold virus. It infects chimpanzees to carry a code and tells cells to build just the spiky outer layer of the SARS-CoV-2 virus. Expectedly, the body’s immune system recognises this as a threat and develop antibodies to fight the spike protein to fight the real virus. On August 26, the India trials started with two volunteers in Pune’s Bharati Vidyapeeth Medical College. The phase II/ III trials are expected to take seven months until March 2021, as per clinical trials registry, India (CTRI).
Zydus Cadila Phase I trials of the candidate showed it was ‘safe and well-tolerated, moving it to Phase II human trials on August 6. The phase I and II trials would take around three months, until October. The trials would expectedly take around a year to complete. If successful, the firm may reportedly produce 100 million doses.
‘Covaxin’ raked up controversy in early July following an Indian Council of Medical Research (ICMR) letter pushing for an August 15 launch. It involves injecting dead SARS-CoV-2 virus, which cannot infect or replicate in those injected with it, with the aim of inducing an immune response by the body. Bharat Biotech wants to produce around 300 million doses of the vaccine.
RBD protein vaccine is developed using the same traditional technique used to make vaccines against Hepatitis B, making it easier to produce as most companies already possess the technical know-how for it. Biological E is expected to conduct human trials for this vaccine candidate in India along with Baylor College of Medicine (BCM) last month. Biological E has the annual capacity to make up to a billion doses of this vaccine.
HGC019 belongs to a newer category, called ‘mRNA’ vaccines, which is coded to tell the cells to recreate the Covid-19 spike protein. On being injected, the cells use the mRNA’s instructions, create copies of the spike protein, and in return is expected to prompt the immune cells to fight it.
A subsidiary of Emcure Pharmaceuticals, Gennova Biopharmaceuticals, intends to initiate human trials in India by October and is also planning global testing in collaboration with partner HDT Bio in the US, Brazil and South Africa. The firm intends to make around 150-200 million doses annually.