AZ unveils detailed data from THALES trial

AstraZeneca has now shared detailed results from the Phase III THALES, showing that a combination of twice daily Brilinta (ticagrelor) and daily aspirin reduced the rate of stroke and death (the composite primary endpoint) by 17% after 30 days compared to aspirin alone in patients who had an acute ischemic stroke or transient ischemic attack (TIA).

The drug giant called the result “statistically significant and clinically meaningful”, and also noted  that the combination significantly reduced the rate of ischaemic stroke (first secondary endpoint) by 21% versus aspirin alone.

On the safety side, the risk for severe bleeding events was 0.5% in the aspirin plus Brilinta group and 0.1% in the aspirin group. Data showed fatal bleeding in 11 patients (0.2%) in the combination arm and zero in the placebo arm, but AZ said the side effects observed in the trial are in line with Brilinta's known safety profile.

Stroke is the second leading cause of death worldwide, with 6.2 million related deaths in 2017, of which 2.7 million were due to ischaemic stroke.

Patients who experience an acute ischaemic stroke or TIA are at high risk of developing subsequent ischaemic events, with particularly high risk within 30 days after the initial event and the highest risk period being the first 24 hours after the initial even

“About one in four stroke survivors go on to experience a second stroke, and the risk is particularly high within the first month after the initial event,” said Dr Clay Johnston, lead investigator for the THALES trial and dean of the Dell Medical School at The University of Texas in Austin, US.  “Early treatment is important to prevent a subsequent stroke that may be disabling or fatal. It is also expected to improve long-term outcomes.”

“Results from the Phase III THALES trial confirm that aspirin plus Brilinta has the potential to be a new effective treatment option for these high-risk patients and we look forward to continuing discussions with regulatory authorities,” added Mene Pangalos, executive vice president, BioPharmaceuticals R&D.

The US is currently reviewing AZ' application to market Brilinta for the reduction of subsequent stroke in patients who experienced an acute ischemic stroke or TIA based on the Phase III THALES trial.

Brilinta is cleared in more than 110 countries for the prevention of atherothrombotic events in adult patients with acute coronary syndrome (ACS) and in more than 70 countries for the secondary prevention of cardiovascular events among high-risk patients who have experienced a heart attack.

Earlier this year, the FDA approved a label update for Brilinta to include the reduction of the risk of a first heart attack or stroke in high-risk patients with coronary artery disease.