By Martins Ifijeh
The world may soon heave a sigh of relieve as two COVID-19 vaccine candidates have shown prospects in preventing the virus among humans, according to early clinical results published by The Lancet Monday.
This is even as the Nigeria Centre for Disease Control (NCDC) has expressed excitement over the development, saying the third phase of the trial vaccines will determine their efficacies against the disease.
The vaccines, developed by the University of Oxford and AstraZeneca have shown signs of inducing an immune response in patients involved in its trials.
According to The Lancet, The trial results found that the vaccines generated two ‘strong’ immune responses: the production of both antibodies and T cells, which find and attack virus cells.
The Director, Jenner Institute, Oxford University, Adrian Hill, said: “We are getting both sides of the immune system stimulated and that is fairly unusual for vaccines.”
An infectious disease expert at Vanderbilt University Medical Center in Nashville, Dr. William Schaffner, said: “It is good news. It is another step forward on the long road to having a COVID-19 vaccine.” Schaffner was however not involved in the vaccine research.
Dozens of teams across the world are working on other potential COVID-19 vaccines.
Moderna, a Cambridge, Massachusetts-based biotech company, published its PHASE 1 trial results of its vaccine last week, and announced plans to begin its final phase of human testing at the end of July. In the phase 1 trial, researchers reported that all 45 volunteers developed antibodies to fighting the coronavirus.
Both the Moderna and Pfizer COVID-19 vaccines in development also suggested immune responses for antibodies and T cells, though Moderna’s T cell response was weaker.
In the Oxford study, the T cell response was noted within 14 days of receiving the vaccine. Immunity was detected for at least 56 days after getting the shot. It’s unclear how long that will last.
Fatigue and headache were the most common side effects reported by the 1,077 study participants, all adults between the ages of 18 and 55.
The clinical trial did not establish whether the vaccine protects against coronavirus infection. That will be determined in the phase 3 trials, which are currently taking place in Brazil, South Africa and the United Kingdom. Trials will also be started in other parts of the world, including the United States.
“We want to look at the efficacy of the vaccine in different populations,” Hill said
The vaccine is made from a weakened form of a common cold virus, called an adenovirus, that’s been genetically modified to carry instructions for cells to make the coronavirus’s notorious spike protein. The idea is that, if the vaccine can instruct human cells to make this protein, the human system can learn to recognize it and better protect against infection.
Early research found that the experimental vaccine induced antibody production in six rhesus macaques. These monkeys are considered to be good proxies for how drugs could work in people because they share a majority of their genes with humans. When the researchers exposed the vaccinated animals to the coronavirus, they did not develop pneumonia or other lung problems.
The global race toward a vaccine for COVID-19 — which, by Monday afternoon had sickened nearly 15 million people worldwide — is moving far more quickly than work on previous vaccines. And there is unlikely to be a single “winner.” As multiple vaccines will likely be necessary to treat the entire world.
Researchers “are working very rapidly. We’re saving time, because we’re doing some things simultaneously, that we used to do in sequence,” Schaffner said. “No corners are being cut.”
Asked whether a finished Oxford vaccine was likely in the next year, Hill said the research was still targeting 2020.
“A vaccine later this year is not impossible. A lot of things would have to go right for that to happen and to be deployed in 2020, but we’re still targeting that.”
On its part, NCDC, while expressing excitement over the development said it was a positive news towards having a safe and effective COVID-19 vaccines.
In a tweet, it said: “Phase I and II trials of the COVID-19 vacine candidate shows promise, however, phase III trials are needed to validate its efficacy against the virus.”