US district court strikes down AstraZeneca’s Pulmicort patent

A US court has ruled that an AstraZeneca patent covering asthma inhaler Pulmicort Respules (budesonide inhalation suspension) is invalid, allowing generic drug makers to enter the market with their own versions.

In a judgment issued on Friday (February 13), the US District Court for the District of New Jersey found that US patent 7,524,834, called “sterile powders, formulations, and methods for producing the same”, was obvious.

The patent was due to expire in 2018, with paediatric exclusivity extending that protection by six months to 2019.

In a statement, Paul Hudson, president of AstraZeneca US, said the company “strongly disagrees” with the court’s decision.

Hudson said that the company is considering its legal options, including filing an appeal against the court’s decision.

AstraZeneca sued Apotex in 2009 (and later Watson Laboratories, now Actavis, Breath Limited, and Sandoz) for infringing patents directed to methods of the use and formulation of Pulmicort’s active ingredient.

In April 2013, in a consolidated action, the New Jersey court ruled that an AstraZeneca patent, US number 6,598,603, which also covers Pulmicort and protects a “method for treating respiratory diseases”, was invalid. The court ruled that the generic makers did not infringe the ‘834 patent.

In October that year, following AstraZeneca’s appeal, the US Court of Appeals for the Federal Circuit reversed and remanded for further proceedings the lower court’s decision that the defendants did not infringe the ‘834 patent, but upheld the court’s decision on the ‘603 patent’s invalidity.

But the district court has now invalidated the ‘834 patent.

On the day of the district court’s latest decision, Actavis announced that it had launched a generic version of Pulmicort Respules. Generic drug maker Teva is already licensed to market a generic version of the drug.

Pulmicort Respules helps to manage asthma symptoms in children aged between twelve months and eight years.