AZD1222 US Phase III trial met primary efficacy endpoint in preventing COVID-19 at interim analysis
https://www.astrazeneca.com/content/astraz/media-centre/press-releases/2021/astrazeneca-us-vaccine-trial-met-primary-endpoint.html
https://clinicaltrials.gov/ct2/show/NCT04516746?term=NCT04516746&draw=2&rank=1
Interim safety and efficacy analysis
N = 32,449
2:1 randomisation of vaccine to placebo
Accruing 141 symptomatic cases of COVID-19
Statistically significant vaccine efficacy of 79% at preventing symptomatic COVID-19
100% efficacy at preventing severe disease and hospitalisation
Vaccine efficacy was consistent across ethnicity and age
Aged 65 years and over, vaccine efficacy was 80%
The vaccine was well tolerated
Favourable reactogenicity and overall safety
Independent data safety monitoring board (DSMB) identified no safety concerns
DSMB conducted a specific review of thrombotic events, as well as cerebral venous sinus thrombosis
(CVST) with the assistance of an independent neurologist
DSMB found no increased risk of thrombosis or events characterised by thrombosis, n = 21,583, receiving at least one dose of the vaccine
The specific search for CVST found no events in this trial
79% white/Caucasian
8% black/African American
4% native American
4% Asian
22% of participants were Hispanic.
Two doses administered, four week interval
Extended interval of up to 12 weeks demonstrated greater efficacy
Supported by immunogenicity data
This evidence suggests administration of the second dose with an interval
Longer interval could further increase efficacy
and accelerates the number of people who can receive their first dose
Stored, transported and handled at normal refrigerated conditions
2-8 degrees Celsius or 36-46 degrees Fahrenheit, for at least six months
Counter argument
https://www.nih.gov/news-events/news-releases/niaid-statement-astrazeneca-vaccine
Concerned by information released by AstraZeneca on initial data from its COVID-19 vaccine clinical trial.
AstraZeneca may have included outdated information from that trial, which may have provided an incomplete view of the efficacy data.
Food and Drug Administration and Centers for Disease Control and Prevention to decide.
After thorough review of the data by independent advisory committees
Source