The Turnstone: talking about vaccines #23

Novavax is here (3 minute read)

Welcome to The Turnstone: talking about vaccines. Here, I share resources to help you have kind and non-judgemental conversations with people who are uncertain about, or opposed to, vaccination. I send The Turnstone out every Sunday - if you’d like them emailed to you directly, you can sign up to my mailing list.

This month, I’m bringing you information about a new Covid-19 vaccine that’s been approved in New Zealand and more than 30 other countries – Novavax.

Image credit: Picture Alliance/ Getty Images

What is the Novavax vaccine?

The Novavax Covid-19 vaccine, officially known as Nuvaxovid, is a vaccine developed and produced by a small pharmaceutical company based in Maryland. It’s important because it uses a different type of technology from the other well-known vaccines that have made it into our arms. Instead of messenger RNA (Pfizer/ BioNTech and Moderna) or viral vector (Oxford/ AstraZeneca and Johnson & Johnson), it is a protein subunit vaccine. This is a more traditional type of vaccine, the same type as the whooping cough and tetanus booster vaccine I wrote about last month.

Here’s a general explanation of how protein subunit vaccines are produced and how they work. (3 minute read and 4 minute video)

What are protein subunit vaccines and how could they be used against COVID-19? | Gavi, the Vaccine Alliance

There’s a slight difference between the general explanation here and the Novavax vaccine. The explanation below says that protein subunit vaccines are produced in yeast cells. Instead of yeast, the Novavax vaccine uses cells from a moth.

Is the Novavax vaccine any good?

Novavax took a while to be approved. The reasons seem to be a combination of luck and management, but the short answer is that they didn’t do a great job at managing the clinical trial and manufacturing processs. But they did make a good vaccine in the end.

In clinical trials, the Novavax vaccine had an overall efficacy of around 90% (against symptomatic disease). Efficacy against moderate to severe disease was higher – comparable to that for the Pfizer vaccine. The trials included multiple variants, including Delta, but not Omicron. I’ve linked below to the published result of the clinical trials if you feel like wading through it. (22 minute read)

Efficacy and Safety of NVX-CoV2373 in Adults in the United States and Mexico | NEJM

What about side effects?

Side effects were similar to those reported for the Pfizer and Moderna vaccines – most often pain where the vaccine was injected, but also other side effects such as tiredness and fever. In the clinical trials, side effects were reported less frequently with Novavax than with Pfizer and Moderna.

Clinical trials don’t tell the whole story, however. There were just under 30,000 participants in the clinical trials, and that isn’t enough to show rare side effects. We do now have some early data from Australia, where more than 30,000 doses have been given. So far, the data from Australia are comparable to what was seen in the clinical trials. But it’s worth noting that many more doses have been given of vaccines such as Pfizer and AstraZeneca, so we know much more about their safety.

Where can I find out more?

Here are some links where you can find out more about the Novavax vaccine.

Article from The Atlantic – it’s a bit old now, but this article gives a good explanation of why the Novavax vaccine took longer than some others, and what its advantages are. (9 minute read)

Novavax Is Now the Best COVID-19 Vaccine - The Atlantic

Comparison from Yale Medicine – covers Novavax as well as Pfizer, Moderna, AstraZeneca and Johnson & Johnson. (14 minute read)

Comparing the COVID-19 Vaccines: How Are They Different? > News > Yale Medicine

Article from Your Local Epidemiologist, one of my favourite sources for Covid-19 information, and it’s available in English and Spanish. (5 minute read)

Two underdog but game changing vaccines: NVX-CoV2373 (Novavax) and CORBEVAX (substack.com)

For New Zealanders – here’s a link telling you how and where you can get vaccinated with Novavax. The bad news is, it isn’t widely available here yet. (5 minute read)

COVID-19 vaccines: Getting Novavax | Ministry of Health NZ

Let me know what you think in the comment box below. And if you know someone who might find this article interesting, please share it with them.