Australia is a step closer to securing a vaccine for Covid-19, and an international deal to produce it locally, if Oxford University's trials succeed.
The indication is New Zealand could benefit as a result, but how far down the global priority list are we, due to our efforts at elimination? The Australian Government has signed a letter of intent with UK-based drug company AstraZeneca to secure the Oxford Covid-19 vaccine.
Photo: MICROGEN IMAGES/SCIENCE PHOTO LIBRARY
It's the most promising vaccine in development, entering phase three trials to evaluate its efficacy, the final step before approval.
University of Otago infectious disease expert Professor David Murdoch tells Kathryn Ryan the chances of New Zealand access a vaccine by early next year are slim, regardless of our position in the queue.
“I’m prepared to be surprised, I’m keeping an open mind… but we’re looking at the middle of next year, although it’s just really speculation at the moment,” he says.
He hopes New Zealand is working with Australia on any vaccine plan, which would make sense for any trans-Tasman bubble.
Australia is in a position to produce the pharmaceutical, while New Zealand’s local manufacturing capability is less advanced. Getting access to the pharmaceutical is an matter of equity and negotiation, he says.
Murdoch is one of three international scientists invited to advise the University of Oxford's Vaccine Group on its safety and efficacy.
As a member of that committee he exercises oversight and gives advice to help with decision-making about the clinical trials with the Oxford vaccine.
He says health officials are looking at who may be prioritised if there is only a certain percentage of the population that can be vaccinated after the first batch of pharmaceuticals becomes available to New Zealand.
“We may have enough for 10 percent of the population initially. So, it’s really important to start thinking about how we would prioritise that and that’s actually happening already.”
The elderly and immune-compromised populations would be looked at, as well as those working at the borders and healthcare workers.
The priorities and modelling become more important when plans to re-open the country are followed through.
The Oxford vaccine is one of five that have progressed to phase-three trials, which involve thousands of people assigned to either receive the vaccine or a placebo. At the end of the trial, specialists will know the effectiveness of the vaccine and the way in which it could be most effectively deployed.
“At the end of these trials, which are absolutely critical, we will know the actual effectiveness of the vaccine… They are the key final studies before we look at licensing and manufacturing and getting all the right approvals. We will be hopefully getting some of these signals later in the year as the trials progress.”
The vaccines have differing ways to delivering the Covid protein spike to the immune system to cause an effective immune response. Scientists are looking for 90 percent effectiveness to preventing the infection, or at the least, preventing the severe consequences of getting the virus.
“We just won’t know this until the end of phase three,” he says.
New Zealand would be the least-effective place to carry out trials due to the low infection rates, so trials are taking place in multiple places with higher rates and differing populations, like in Brazil.
If the trials are found successful by the end of the year, it would be mid-2021 until a product was available.
Murdoch says it is important to plan for various scenarios, including one where any vaccine used would have varying degrees of efficacy, falling short of stopping infection. The vaccine in any case would be pivotal in deciding New Zealand’s response to the virus going forward.
“We’re all very optimistic, but we haven’t got the vaccine yet. We need to develop an effective vaccine and I think we are quietly optimistic because of the results so far, but we need to be prepared for a number of eventualities.”
