Thread by @profshanecrotty

Novavax COVID-19 vaccine 90% effective in USA Phase 3 trial! 🧵

This is a protein subunit vaccine

🔵 90% effective against COVID-19 cases
🔵 ~100% effective against "Moderate to severe" COVID-19 (14 cases total in the trial, all in placebo group)
🔵 Very good safety profile

Vaccine efficacy: 90.4% against any COVID-19. Very good!
No moderate or severe cases in the vaccinated group. Very good!
14 moderate to severe in the placebo group.
So, "100%" protection, for 14 events measured.

(The trial was done with a 2 to 1 ratio of vaccinated to placebo people, so the math takes that into account)

The definitions of Moderate and Severe (to fatal) cases is similar to the RNA vaccine clinical trials, and is reasonable. (Clinicians generally define Moderate differently, as a hospitalized case, so the language in the field is confusing).

The Novavax vaccine worked well against the B.1.1.7 variant (alpha). This was expected, as the vaccine had worked well against alpha in the UK clinical trial in January. Still, good news!

The vaccine appears to be effective against other variants, but a detailed analysis will be needed of the numbers (which will have somewhat limited conclusions limited by the smaller numbers of cases once everything is divided up).

It seems likely the vaccine had high efficacy against B.1.526 (New York), otherwise the case # would have been skewed. But I defer to epidemiologists on that topic.

Really nice safety profile of the vaccine.
Very little reactogenicity.

Novavax Vaccine trial features:
Very nicely done trial with ~30,000 participants, including almost 4,000 age 65 and over, and broad demographic coverage.

reuters.com/business/healt…

Here's a post on the original Novavax Phase 3, in the UK and South Africa:

https://twitter.com/profshanecrotty/status/1355259172640591872?s=20