The FTSE 100 pharma company said the jab was well tolerated, and the independent data safety monitoring board (DSMB) identified no safety concerns related to the vaccine.
The DSMB conducted a specific review of thrombotic events, as well as cerebral venous sinus thrombosis (CVST) with the assistance of an independent neurologist.
The DSMB found no increased risk of thrombosis or events characterised by thrombosis among the 21,583 participants receiving at least one dose of the vaccine. The specific search for CVST found no events in this trial.
This interim analysis was based on 32,449 participants, 141 of which developed symptoms of COVID-19. The trial had a 2:1 randomisation of vaccine to placebo.
The inoculation was also 79% effective at preventing symptoms, with comparable results across ethnicity and age and 80% efficacy in participants aged 65 years and over.
The firm will continue to analyse the data and prepare for the primary analysis to be submitted to the US Food and Drug Administration for Emergency Use Authorisation in the coming weeks.
It will also be submitted for publication in a peer-reviewed journal.
“The results from this trial are a further, important validation of the efficacy and safety of AZD1222 [the vaccine], in particular with respect to the efficacy in older age groups and on safety issues concerning blood clots,” analysts at Shore Capital commented.
“The trial results here are also encouraging in finding no evidence of a link between the vaccine and blood clots, which is consistent with the largest ‘real-world’ pool of data that has been collected in the UK given the country’s excellent vaccine rollout.”
“Although it is important all safety signals are thoroughly assessed, the data suggesting a risk of blood clots was weak and delaying the vaccine rollout on the back of such a signal may ultimately have cost more lives than it will have saved. This is because although the link between the vaccine and blood clots was (and is) unproven, the risk of severe COVID-19 in vulnerable groups is very, very real and the vaccines are extremely effective in this regard.”
Shares rose 1% to 7,200p early on Monday.
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