New data from a UK study of Novavax is out, and it looks really good: 96.4% against COVID Classic and 86.3% against B.1.1.7, with fewer side effects than Pfizer/Moderna/AZ. (No sign of blood clots, either, but rare events like that are unlikely to show up in a trial.)
Meanwhile, a Novavax trial in South Africa looked… not as good, with efficacy of only 51% in HIV-negative people who had not had COVID before. It was significantly more effective than catching COVID Classic, however: the same study found that 5.9% of seropositive patients caught COVID vs. 8% of seronegative patients.
Participants in the UK Novavax trial are pissed off. People in the UK need proof of vax to travel to Europe, and because Novavax is not approved yet, they can’t show proof of vaccination.
One of my friends wondered if Canadians who got AZ would be able to enter the US, since it has not been approved there yet. Not to worry, the US does not require proof of vax to enter.
A study (from Feb, which I think I missed the first time around) on says that for AZ, a short dose1->dose2 interval (<6 weeks) gave about 55% efficiency after two doses, but it was boosted to 81% when they waited >12 weeks.
Note that the 55% number looks crappy, but part of the study was done in South Africa, which means B.1.351, which AZ is shit against. Except that if you draw out the dosing, it’s better! Alas, they didn’t break out the South African study separately.
However, that study also shows that people who got their second dose after 12 weeks generated fewer T cells. That means that the protection might not be as durable. We can’t find out the answer to that without time.