AstraZeneca has suffered a slight setback this morning with the news that regulators need more time to decide on whether to approve the bloodthinner Brilinta.

The US Food and Drug Administration has extended the Prescription Drug User Fee Act date on Brilinta (ticagrelor) from September 16 to December 16. In July, the agency's Cardiovascular and Renal Drugs Advisory Committee recommended the drug to reduce the risk of major adverse cardiac events in patients with acute coronary syndromes.

The panel voted 7-1 in favour of two questions that asked whether Brilinta should be approved for use in patients undergoing percutaneous coronary intervention, as well as in patients being medically managed and not expected to undergo surgical treatment.

The basis of the filing is the 18,624-patient PLATO study, the Phase III head-to-head trial comparing the drug plus aspirin with Sanofi-Aventis/Bristol-Myers Squibb’s big-selling bloodthinner Plavix (clopidogrel), also with aspirin. However FDA staffers noted that there was a difference in effectiveness between US and non-US participants in the trial.

Whether this explains the three-month delay on the PDUFA date is not clear as no specific reason has been given. AstraZeneca spokeswoman Abigail Baron told PharmaTimes World News that "we remain confident in the application and will continue to work closely with the FDA to support the review".

Brilinta, the jewel in the Anglo-Swedish drugmaker's pipeline which is expected to be a blockbuster, is currently under review in nine other territories, including the European Union, Canada and Brazil.