AstraZeneca responds to FDA on ticagrelor
AstraZeneca has replied to the FDA’s complete response letter (CRL), which explained why there was such a difference of outcomes between U.S. and non-U.S. patients in the PLATO trial that compared ticagrelor (Brilinta) with clopidogrel.

The company received the CRL regarding the new drug application (NDA) Dec. 16, 2010.

Within the CRL, the FDA requested that the company outline interactions between ticagrelor and high-dose aspirin. The London-based AstraZeneca wrote that the supplementary data support that the reason for the differences in the effects observed in the U.S. and non-U.S. patient subsets in the PLATO trial was due to the interactions between the drug and high-dose aspirin.

The FDA’s CRL did not request AstraZeneca to conduct any further clinical trials as a prerequisite for approval of ticagrelor’s NDA. Once there is a CRL issued and NDAs are resubmitted and accepted by the FDA, the agency will then conduct the review and deem it either a class 1 (two-month review cycle) or class 2 (six-month review cycle) review.

Brilinta is a P2Y12 receptor antagonist that is currently under review in 21 countries as a treatment for acute coronary syndromes (ACS) patients to reduce cardiovascular events when compared to clopidogrel. The drug has already been approved in 30 countries.

The NDA submission is based on the results of the PLATO trial that enrolled 18,624 ACS patients in 43 countries and compared the outcomes of ticagrelor versus clopidogrel (Plavix, Bristol-Myers Squibb/Sanofi-Aventis).