Court invalidates patent for prostate cancer drug Zytiga®

Johnson & Johnson (NJ, USA) have recently announced that the District Court of New Jersey has issued a ruling that invalidates all claims to the US Patent No. 8,822,438 for the prostate cancer drug Zytiga® (abiraterone acetate). The patent infringement case was filed against several companies who have submitted FDA applications to market generic versions of the drug.

The contested patent covers the use of the drugs active ingredient with prednisone and is the only unexpired patent still protecting Zytiga. The ability of prednisone to reduce pain and side effects in cancer patients gives a strong incentive to combine it with the cancer drug. Currently more than 85% of Zytiga prescriptions are given in proximity to prednisone.

Representatives from Janssen Pharmaceutica (Belgium), a company of Johnson & Johnson, plan to appeal the decision and no launch of generic products can occur before at least the 31 October 2018, pending the result of the appeal process. Commercial launch of generic abiraterone acetate prior to the outcome of the appeals would be considered an at-risk launch.

In Europe, Zytiga is protected by regulatory exclusivity through September 2022.

Companies seeking to commercialise generic versions of Zytiga include Hikma Pharmaceuticals (London, UK), Endo International’s Par Pharmaceutical (NJ, USA) and Dr Reddy’s Laboratories (Hyderabad, India).