A coronavirus vaccine jointly developed by the University of Oxford and drug giant AstraZeneca has shown an average efficacy of 70 per cent in early trials and if approved, could be rolled out later this year.
Results found the vaccine ranged from 62 and 90 per cent efficacy depending on the dosage given to participants.
The 70 per cent average is lower compared with the efficacy of coronavirus vaccines trialled by rivals Pfizer/BioNTech and Moderna which have come in above 90 per cent.
Professor Andrew Pollard, director of the Oxford Vaccine Group, said the discovery marked a “really exciting day” and a major step towards the end of the coronavirus pandemic.
He said “intriguingly”, a subgroup in the study that received a half dose of the vaccine initially followed by a full second dose saw results around 90 per cent effective.
The reasons for this are unclear with “more work to be done” he said, adding that it could be that the initial smaller dose is “priming the immune system” to respond.
But Prof Pollard said it’s difficult to compare results between companies when “we don’t know exactly what everyone is measuring.”
“In the end, what we need to be able to do to get back to normal and control the pandemic is to have people around the world vaccinated. We need all the vaccines to be able to do that.”
“These findings show that we have an effective vaccine that will save many lives,” he said, adding that if half doses are given it could increase the number of people able to be vaccinated.
“Today’s announcement is only possible thanks to the many volunteers in our trial, and the hard working and talented team of researchers based around the world.”
AstraZeneca chief executive Pascal Soriot said the studies show the vaccine will be “highly effective against COVID-19 and will have an immediate impact on this public health emergency.”
WHICH VACCINE WILL AUSSIES GET?
The news has been hailed by the makers as overwhelmingly positive as it shows there are likely to be at least three different options for the type of mass inoculation the COVID-19 pandemic will require.
So which one are Australians likely to receive?
There are some key differences between the UK’s Oxford version and the US-based Moderna and Pfizer versions.
The Oxford vaccine, called ChAdOx1 nCoV-19, is made from a weakened version of a common cold virus (adenovirus), that has been genetically changed so that it cannot grow in humans.
Adenovirus vaccines have been researched and used extensively for decades, with the benefit that they are stable, easily made and can be stored at the same temperature as a domestic fridge.
This means they could be easily distributed and deployed using the existing supply chain based on using GP surgeries and pharmacies. It also means it could be easier to administer in hotter climates or developing countries where such facilities for cold storage do not exist.
The Moderna and Pfizer versions by contrast, rely on mRNA technology and are created in a lab using chemicals, enzymes, bacteria or live cells.
Scientists essentially make a synthetic version of the virus’s messenger ribonucleic acid (mRNA). This then prompts the body to make a particular protein, which is detected by the immune system and this causes the immune system to make antibodies to fight against it.
As for which one Australians will get first, it’s difficult to know as all three need to pass final regulatory approval abroad and in Australia.
The government has not outlined any priority system, however deals signed suggest that Australia has placed a large bet on the Oxford version, which will also be made in the country by CSL, based in Melbourne.
Overall, the government has invested more than $ 3.3 billion covering five vaccines which must pass Therapeutic Goods Administration approval before being used. They include:
University of Oxford/AstraZeneca
• 3.8 million doses delivered to Australia in early 2021
• 30 million doses manufactured in Australia from early 2021 through to September 2021 in monthly batches
• CSL will manufacture these doses on behalf of AstraZeneca
• 10 million doses will be available from early 2021
• Will be manufactured offshore
• Australia will have the option to purchase additional doses where supply is available
University of Queensland/CSL
• This is still in Phase 1 trials so unlikely to be the first used
• 51 million doses will be available from mid-2021
• These doses will be manufactured in Australia by CSL
• Also still in Phase 1 trials
• 40 million doses will be made available in Australia during 2021
• This is a global facility designed to allow equal access to a range of vaccines under trial, including the Moderna version.
REDUCTION IN TRANSMISSION
Oxford’s Jenner Institute’s Professor of Vaccinology, Sarah Gilbert, said early data shows the vaccine had helped with a “reduction in the number of asymptomatic transmissions” in what could be a key way to help reduce the spread of the virus.
She said early results also show that no severe cases were hospitalised with COVID after using the vaccine.
Prof Gilbert said the results bring the world “closer to the time when we can use vaccines to bring an end to the devastation caused by SARS-CoV-2.
“We will continue to work to provide the detailed information to regulators. It has been a privilege to be part of this multinational effort which will reap benefits for the whole world.”
AstraZeneca said it would “immediately prepare regulatory submission of the data to authorities around the world that have a framework in place for conditional or early approval”.
It added that it would seek emergency-use listing from the World Health Organisation to accelerate vaccine availability in low-income countries.
The company’s executive vice-president of operations and information technology, Pam Cheng said “we have not wasted a single day” in setting up a global supply chain for the vaccine.
She estimated 200 million doses would be available by the end of 2020 and 700 million doses by end of March 2021.
More than 23,000 adults are currently being assessed in the trials, with the number expected to rise to up to 60,000 people.
“Clinical trials are also being conducted in the US, Japan, Russia, South Africa, Kenya and Latin America with planned trials in other European and Asian countries,” Oxford said in a statement.
– With wires