AstraZeneca and Abbott Laboratories have announced that a project to develop the first statin/fibrate combination in a single pill is to move into late-stage trials.

The firms are starting Phase III trials of AstraZeneca’s blockbuster Crestor (rosuvastatin) with the US group’s investigational new compound ABT-335 (fenofibrate) in a fixed-dose combination treatment into Phase III clinical trials. The single pill will target “all three major blood lipids,” the firms say, namely the lowering of ‘bad’ low-density lipoprotein cholesterol and triglyceride levels, and also increased cardioprotective ‘good’ high-density lipoprotein cholesterol levels.

The partnership dates back to a deal signed by the two companies in July 2006 under which they would jointly develop a product combining Crestor with either Abbott's older fenofibrate drug Tricor or ABT-335, which is due to be filed with the US Food and Drug Administration as a monotherapy (as an adjunct to diet) by the end of 2007. That they have plumped for the latter suggests considerable confidence in the new compound.

Abbott will continue to be responsible for the clinical trial programme and be responsible for regulatory registration of the new combination therapy, while AstraZeneca will hold the New Drug Application. A regulatory application is pencilled in for submission in 2009.

Crestor patent challenges looming?

The news came as analysts at Citigroup noted that five generic firms have submitted ‘drug master files’ with the FDA to make a generic version of Crestor, suggesting a patent challenge could be on the cards. The main US patent on the drug does not expire until 2016 and it was recently extended by four years, but a challenge can happen well before then.

Citigroup said in a research note that there is typically a delay of a month or two after a drug master file is submitted before the notification of a patent challenge is published. The companies looking to challenge Crestor, which had second-quarter sales of $1.3 billion, up 47%, are Teva of Israel, China’s Changzhou Pharmaceutical and the Indian trio Glenmark, Aurobindo and MSN Laboratories.