Singapore: In a blow to AstraZeneca, a multinational pharmaceutical company, the Federal Court of Australia has found three patents protecting its drug Crestor (rosuvastatin) to be invalid.

The three patents are a formulation patent with an expiry date in 2020, a patent related to the use of rosuvastatin for treating heterozygous familial hypercholesterolemia with an expiry date in 2021, and a third patent related to the use of rosuvastatin for treating hypercholesterolemia with an expiry date in 2020. The patents were challenged by Apotex, Watson Pharma and Ascent Pharma.

The court's decision, which is limited to Australia, will have no impact on the validity of patents related to Crestor in other countries. A press statement issued by AstraZeneca states that the development will not impact its financial guidance for 2013.

Total sales of Crestor in Australia for 2012 were approximately $350 million.

AstraZeneca said it was disappointed by the court's decision that found the three patents invalid. The company added that it remains committed to defending its intellectual property protecting Crestor in Australia and is carefully reviewing this decision and evaluating all legal options, which include filing an appeal and seeking to maintain existing preliminary injunctions.