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Latest developments in COVID-19 vaccines – Expert Briefing

The SMC led an online media briefing about the recent progress in vaccine development for COVID-19.

Professor David Murdoch, University of Otago

The full briefing is available here and an excerpted transcript is below.

We’ve seen a flurry of results from recent vaccine candidate trials. What have we learned from these results in the last couple of weeks?

It’s been an extraordinary year in terms of the whole vaccine scene, which has been changed completely. The speed with which things are happening is really astronomical. But I should say for a start that it’s unusual that we get these announcements – we’re not used to that in clinical trials. These are what we call interim analyses – these are pre-planned times before the study is completed when an independent committee will check the data safety and effectiveness and just make sure there’s nothing untoward with the study, or any safety issues. So we normally don’t hear anything about it, but it’s a normal part of the study. 

This time, there were good news headlines from all of them, and so we’ve got these fairly simple banners which said that these vaccines are very effective – and that’s pretty much all the information we have. There is a little bit more from some, but we clearly haven’t been able to see the data, so there’s a big caveat that we’d like to see the data – we want to be able to interrogate it in greater detail to understand it – but the headlines are fairly impressive. I mean if we’re talking about effectiveness in the range of above 90% in terms of vaccines, that’s very big. We’re really saying if somebody was exposed to Covid, if they had the vaccine, there’s a 90 plus percent chance they’re going to be protected against it, so that’s high as far as vaccines go.  

This is if it’s borne out, and obviously we have lots of other questions. What were the groups? Is it all age groups or other risk groups? And we still don’t know things like how long immunity lasts for. But the headlines are impressive, and we hope that they are borne out. 

When it comes to addressing those questions, what are you expecting to happen next?

These results have come out before the studies are completed. All the studies have a pre-specified estimate of the size of the study they need to statistically give it enough power so that you can make valid conclusions. They will know in this case that they have to have so many participants in the study who get Covid, whether they get the vaccine or not. 

Once they reach that, they can then close the study, finalize the data, lock it, and break the code. So then investigators for the first time would be told who had the vaccine and who didn’t, and then they can do the analysis, and then we get all the detail. What were the different patient groups? Is it in the elderly as well as the young? Is it preventing severe disease or just mild disease, or both? All of that information will then come out, so actually the next step is for us to see that. 

Which other international vaccines are you keeping an eye on? And what stage of development are these at?

To be honest, we’re really trying to keep abreast of a whole lot – which is over 200 – and that’s a really tough job, but I think we’re keeping an open mind. What t we hope is that all the different platforms perform equally as well. It’s important to remember that all the different vaccine platforms are essentially trying to present the spike protein, which is part of the surface of the virus, to the human immune system, they’re just doing it in different ways. But of course we don’t know their effect until we test them. Many of these platforms have never been used before for vaccines, so there’s huge interest in seeing how they perform. 

There are other vaccines coming, and we’re clearly interested in all of those. There are the various Chinese studies coming through, there’s the Astra Zeneca one which the University of Oxford is part of and we should expect their results before the end of the year. With the Russian vaccine, Sputnik, we’ve seen little bits of data, but we’re obviously interested to see more comprehensively what they can produce. 

The Vaccine Alliance Aotearoa New Zealand has been tasked with screening, trialing and accelerating the development of COVID-19 vaccines. What we know about vaccines that are being trialed or developed here in New Zealand?

We haven’t heard a lot about that yet. We know that it has been established, that it’s been funded, that it’s meant to be moving fairly swiftly, but we’re still waiting to hear about which candidates they might be evaluating. 

What do you think of the New Zealand Government’s portfolio approach to vaccines? Is that something that we’ve seen in the past for other types of disease?

I think this is a situation that the world has not been in before. We are all interested in one product, that hasn’t been produced yet, and everyone wants it to cover the whole population, so it is an extraordinary situation. But many countries are following this approach.  

There is obvious concern about vaccine nationalism, where countries just want to try and purchase as much as they can, but there is a real concern about equity of access throughout the world. So we have this collaborative venture called COVAX, which is put together by a number of entities including the World Health Organization, that’s striving very hard to work with vaccine companies – and New Zealand has joined that, along with most countries in the world actually. We make financial contributions to that which is great because the World Health Organization would stress that’s the most important thing to do to avoid vaccine nationalism.  

We are, in addition, doing like many other countries and actually making some advanced purchase agreements with the individual companies. There is an ongoing process of putting together a portfolio of some promising candidates and having those options – so we’re kind of working both ways. 

In preparation for that time where vaccines are ready to be distributed, what kind of infrastructure does New Zealand need to develop to roll out either one successful vaccine, or perhaps multiple different vaccines for different subgroups of the population?

I think the first thing to say is that we know how to roll out vaccines. The world knows the key things that we need to do. And that’s not playing it down – I mean this is a big logistic exercise, but the pieces in the puzzle, we kind of know.  

The thing that is a bit different is the fact that it will be more than one vaccine, and they’ll have slightly different storage conditions, and other factors. So working that all together, sensibly, with logistics, is going to be a big challenge. But the work has been going for quite a while to prepare for that, getting that infrastructure for distribution and for storage in place. The Pfizer vaccine, assuming that comes through and the storage conditions don’t change, will require minus 70 – 80 degrees Celsius freezers, and we have them in laboratories, but there aren’t a lot of them, and they’re expensive. But I understand the purchasing is well advanced and they would be strategically located around the country.  

So the storage, the distribution, the decisions about who will get the vaccine first have all been talked about for a while. Plus we need community engagement, in terms of all of the messaging around vaccine delivery, and then just having staff. We also need to have the system set up so we can monitor the vaccine program – once we get a vaccine underway we don’t just leave it to be rolled out. There’s an ongoing process, even for vaccines we know well, to look for performance and safety. All of that will be part of this preparation, to be sure. 

How confident do you feel about New Zealanders and their attitudes towards vaccines?

We’ve done this for a long time and it’s important to get the honest messaging out there and get the science explained. I mean we should know how to do this, and we heard the Director General of Health  saying he is aiming for 95% vaccine coverage which is what we aim for with the childhood immunization program, and that’s absolutely what we should be doing. 

But you know, I don’t want to downplay how hard you have to work, and it’s multifaceted. It involves knowing the different community groups, making sure all parts of the country have access to information and are engaged. We need to provide information about the vaccines, explaining the good science, explaining the evidence, and presenting it in a way that people understand. And then having the right people delivering the vaccine in the various communities, having it accessible – you need all these elements to have a successful campaign. It does require hard work, but the key elements are very familiar.