Data from three studies raises hopes on potential COVID-19 vaccine
NEW DELHI | JULY 21, 2020:
Early data obtained from three potential COVID-19 vaccine trials on July 20 have provided hope that a vaccine can train the immune system to recognize and fight COVID-19 without serious side effects.
However, experts are not sure whether the results will protect the billions of people and put an end to the global pandemic.
A vaccine developed by British drugmaker AstraZeneca in collaboration with Oxford University induced an immune response in all participants who received the doses without any side effects.
Meanwhile, a vaccine developed by CanSinoBiologics Inc and China's military research unit induced an immune response in most of the 508 healthy volunteers.
However, 77 percent of the volunteers experienced minor side effects.
Both the AstraZeneca and CanSino vaccines use a harmless cold virus known as adenovirus to carry genetic material from the COVID-19 virus into the body.
"Overall, the results of both trials are broadly similar and promising," said Naor Bar-Zeev and William Moss – two vaccine experts from Johns Hopkins Bloomberg School of Public Health.
However, the CanSino candidate showed signs that people who had previously been exposed to the particular adenovirus in its vaccine had a reduced immune response.
According to the study authors, this is "the biggest obstacle" for the vaccine to overcome.
Meanwhile, German biotech BioNTech and US drugmaker Pfizer Inc released details on a different type of vaccines that uses ribonucleic acid (RNA) – a polymeric molecule essential in various biological roles in coding, decoding, regulation and expression of genes.
The vaccine directs the cells to make proteins that mimic the outer surface of the COVID-19 virus. The body is then able to recognize the virus-like proteins as foreign invaders and can mount an immune response against the actual virus.
The vaccine-induced virus-neutralizing antibodies in volunteers who were given two doses.
This announcement comes in the wake of Moderna Inc's vaccine trial last week which also showed promising early results. Moderna's vaccine also uses a messenger RNA platform.
"It is encouraging that all these vaccines seem to induce antibodies in people," said former World Health Organization (WHO) Assistant Director-General, Marie-Paule Kieny, of the French research institute Inserm.
"This proves that science is moving forward very quickly, which is a good sign," Kieny added.
It is a fact that just 6 percent of vaccine candidates end up making it to market after years of testing.
Vaccine makers are attempting to bypass this through faster trials and by manufacturing the vaccines even before they prove successful.
Quite a few manufacturers have US government backing to come up with a vaccine by the end of the year.
The Oxford/AstraZeneca vaccine is one of 150 vaccines in development globally. It is also considered the most advanced.
Late-stage trials are being performed in Brazil and South Africa will soon begin in the United States.