FDA Approval Delayed for Anti-clotting Agent Brilinta

The FDA has again delayed approval for AstraZeneca’s blood thinner Brilinta (ticagrelor), asking the drug maker to supply additional information and analysis of data from the PLATO study.

According to a news release from AstraZeneca, the FDA issued a complete response letter (CRL) for the New Drug Application (NDA) for Brilinta that requested additional analyses of the PLATO data but “did not request that additional studies, including clinical studies, be conducted as a prerequisite for approval of the ticagrelor NDA.”

The news release says that although AZ is “evaluating the contents of the CRL and will respond to the agency's request for additional analyses of the PLATO data as soon as possible,” the company “remains confident in the NDA submission for ticagrelor and in its ability to respond to the agency's questions.”

Reports on this news have noted that Brilinta received marketing approval in Europe earlier this month, prompting speculation that the FDA would follow suit. With today’s announcement that has not proven to be the case, however. Speculation as to the nature of the FDA’s request for additional analysis of PLATO data has focused on concerns that “Brilinta doesn't work as well in American patients as it does in does in those overseas.” According to a FOX Business report, a brokerage Shore Capital note to investors said that “While it is difficult to speculate regarding the exact nature of the FDA's requests, there is a high likelihood that it will be regarding the data from the U.S. cohort and the role of high dose aspirin in generating the US. data.”

CardioBrief has a link to a report from a Leerink Swann research analyst that says “Unless FDA’s request for additional analysis is straightforward and can be turned around rapidly, we believe a 12-month delay is a realistic scenario for AZ assuming 6 months to submit the add’l and a subsequent 6 month review. Historical concerns and issues raised by the panel and FDA focused on the aberrant US and North American subset analyses which raised questions about (1) a potential interaction with high-dose aspirin; (2) an effect on statin metabolism; and (3) differences in treatment algorithm’s between the US and other markets that would result in diminished efficacy.”