The wait for an effective COVID-19 vaccine is far from over. However, amidst the dark clouds, a ray of sunshine in the form of vaccine development results has hit the headlines and has brought a glimmer of hope in the minds of many.
Currently, there are 23 coronavirus vaccines in the clinical trials around the world and another 140 in early-stage development, showing that the race to defeat the virus has started to take shape. One vaccine candidate, being developed by clinical research teams at Oxford University’s Jenner Institute and Oxford Vaccine Group in collaboration with AstraZeneca seems to have taken an early lead in the race towards the discovery of a safe, effective and accessible vaccine against the novel coronavirus. Here’s everything you need to know about the vaccine, known as ChAdOx1 nCoV-19.
How does the vaccine work?
The vaccine, which belongs to a category called non-replicating viral vector vaccines, has been genetically engineered from a weakened version of a common cold virus (adenovirus) from chimpanzees, which has been modified so it cannot grow in humans. The spike glycoprotein from the virus, that causes COVID-19, have then been added. “We are hoping to make the body recognize and develop an immune response to the spike protein that will help stop the SARS-CoV-2 virus from entering human cells and therefore prevent infection,” the university said.
The body’s immune system is expected to recognise the spike protein as a potentially harmful foreign substance and starts building antibodies against it. Once immunity is built, the antibodies will attack the real virus if it tries to infect the body.
What does the result suggest?
The results of the Phase I/II trial published in the scientific journal, The Lancet, indicate no early safety concerns and induces strong immune responses in both parts of the immune system. The vaccine provoked a T cell response within 14 days of vaccination (white blood cells that can attack cells infected with the SARS-CoV-2 virus), and an antibody response within 28 days.
Phase I/II data for our coronavirus vaccine shows that the vaccine did not lead to any unexpected reactions and had a similar safety profile to previous vaccines of this type. The immune responses observed following vaccination are in line with what previous animal studies have shown are associated with protection against the SARS-CoV-2 virus, although we must continue with our rigorous clinical trial programme to confirm this in humans.Prof. Andrew Pollard, Chief investigator of the Oxford Vaccine Trial at Oxford University
The study also found the strongest immune response in the 10 participants who received two doses of the vaccine, indicating that this might be a good strategy for vaccination.
The Phase I/II trial of the vaccine has been evaluated in more than 1,000 healthy adult volunteers aged between 18 and 55 years in a randomised controlled trial. A subset of these volunteers (10 people) received two doses of the vaccine. Between April 23, 2020 and May 21, 2020, 1077 volunteers received the vaccine ChAdOx1 nCoV-19 or a placebo MenACWY vaccine. There were no serious adverse health events related to ChAdOx1 nCoV-19.
Is it safe?
There were no dangerous side-effects from taking the vaccine. However, the vaccine showed mild to moderate adverse reactions, including pain, feverish feelings, chills, muscle aches, headaches, and malaise. The effects were reduced using prophylactic paracetamol, according to the study. The study suggests that 70% of the people on the trial developed either fever or headache.
“There is still much work to be done before we can confirm if the vaccine will help manage the COVID-19 pandemic, but these early results hold promise,” said Prof. Sarah Gilbert from the University of Oxford.
What are the next steps?
The current results focus on the immune response measured in the laboratory, so further testing is needed to confirm whether the vaccine effectively protects against infection. More than 10,000 people will take part in the next stage of the trials in the UK. Meanwhile, the trial has also been expanded to other countries as well since the levels of coronavirus are low in the UK.
There will be a large trial involving 30,000 people in the US as well as 2,000 in South Africa and 5,000 in Brazil. There are also calls to perform “Challenge Trials” in which vaccinated people are deliberately infected with the coronavirus. However, there are ethical concerns due to the lack of treatment protocol.
When will it be available?
The Oxford University said its best-case scenario is for an efficacy result from Phase III by the fall (22 September- 21 December), alongside the ability to manufacture large amounts of the vaccine, but stressed that the time frame is highly ambitious and subject to change.
The vaccine needs to work in late-stage trials. Large quantities need to be produced, and regulators have to agree to licence it quickly for emergency use. All these three things have to happen and come together before we can start seeing large numbers of people vaccinated. Millions of doses could be made ready by September, but Andrew Pollard, Chief investigator of the Oxford Vaccine Trial at Oxford University believes it is unlikely that the vaccine would be available at a very large scale before the end of 2020.
Availability In India?
The Serum Institute of India, which has tied up with Oxford and AstraZeneca, plans to make “millions of doses” of the vaccine over the next three months, after receiving a manufacturing licence. The firm is expected to manufacture the vaccine for low- and middle-income countries.
However, Serum will have to conduct phase III trials in India before the vaccine can be launched. So far, the firm has received permission to manufacture certain doses for testing purposes, said a senior government official. “We will be applying for the licensure trials to the Indian regulator in a week’s time. As soon as they grant us permission, we will begin with the trials for the vaccine in India,” said Adar Poonawalla, CEO of Serum Institute.
What if the vaccine doesn’t work?
A high proportion of vaccines are found not to be promising even before clinical trials, and a significant proportion of those tested in clinical trials don’t work. “If we are unable to show that the vaccine is protective against the virus, we would review progress, examine alternative approaches, such as using different numbers of doses, and would potentially stop the program,” the university said in a statement.
However, British drugmaker AstraZeneca has started manufacturing the potential coronavirus vaccine ahead of the final trial results and has doubled its capacity to two billion doses. The pharmaceutical giant, which has already agreed to provide the U.K. and the U.S. with doses, said it has secured agreements to supply the vaccine to low and middle-income countries through health organizations, including two backed by Bill and Melinda Gates Foundation.
Meanwhile, When Asked about the pricing of Oxford’s COVID-19 vaccine in India, Serum Institute of India CEO Adar Poonawalla said, “It is too early to comment on the vaccine’s price. However, we will keep it under ₹1,000 per dose.” He further expressed certitude that the governments across such nations will procure and distribute the vaccine “without charge”.
Its not just the researchers, the entire world is looking forward to the further developments of the vaccine. Humanity is desperate for an effective vaccine and there are huge expectations on this one. Can this “small step for man” be a “giant leap for mankind?” Let’s keep our fingers crossed and hope for the best!