- Astra and Oxford's vaccine candidate shows average 70% efficacy in two regimens
- Developing economies dependent on vaccine since it's cheaper, doesn't require ultra-cold
- 9.6 billion vaccine doses have been purchased, mainly by high income countries
After both Pfizer/BioNTech and Moderna's coronavirus vaccines showed over 95% effectiveness in interim analysis, AstraZeneca and Oxford University announced their AZD1222 vaccine showed an average efficacy of 70% in early results from late-stage trials in the U.K. and Brazil. Last week we learned the preventative, which unlike the other two is viral vector-based and not mRNA technology, is safe and produced an equally strong immune response in both young and old adults.
Although on first glance at news headlines it appears this vaccine candidate has lower effectiveness than its competitors, the "70%" figure is actually an average of outcomes from two dosing regimens – one of which was 90% effective (a half dose, followed by a full dose) and the other that was 62% effective (two full doses). Fortunately, the more effective regimen requires a lower dose, which means more people can be vaccinated with planned supply if it's used.
The Vaccine Frontrunners
Keeping It Cool
Another piece of good news is Oxford/AZN's vaccine can be stored, transported and handled at normal refrigerated conditions 2° to 8°C (36° to 46°F) for at least six months. Meanwhile, Moderna's vaccine needs to be kept at -20° C (-4°F) to last six months, and Pfizer's vaccine must be kept at –70° C (–94° F) or lower, temperatures colder than winter in Antarctica, to remain stable. This is especially important for developing economies, which will depend largely on the significantly cheaper AstraZeneca vaccine. Both Moderna and Pfizer have refused to make a no-profit for their vaccines unlike AstraZeneca, Johnson and Johnson, and GSK. Novavax has made an equitable global delivery pledge.
Fixing the Vaccine Wealth Gap
Pharma profits from COVID will be in focus as calls to waive vaccine patents and ensure equitable access to a usable vaccine grow. Alongside the race to invent a vaccine, there has been a bidding war by wealthy countries looking to secure early access to doses.
Many high-income countries have hedged their bets by advance purchasing enough doses to vaccinate their populations several times over, according to researchers at Duke University. They say that 9.6 billion doses have already been purchased, currently under negotiation or reserved as optional expansions of existing deals.
Activists at non-profit Global Justice Now estimate that around 80% of the doses Moderna and Pfizer can produce by the end of 2021 have already been bought by the richest governments.
“We in the AIDS movement have seen in the past how corporations use monopolies to artificially restrict supplies of life-saving medicines and inflate their prices," said Winnie Byanyima, Executive Director of UNAIDS and Under-Secretary General. "UNAIDS and other members of the People’s Vaccine Alliance are calling for a new approach that puts public health first by sharing knowledge and maximizing supply. Anything short of that will lead to more deaths and economic chaos, forcing millions into destitution."