Is Pfizer being a big bully here? from www.deccan.com Long road to rejection Hyderabad, Feb. 28: When the US Court of Appeals for the Federal Court of New Jersey finally ruled in favour of Pfizer, Inc, and against Dr Reddy's, in the case of amlodipine maleate, the specialty drug was hanging in the balance for two full years. Dr Reddy's had filed a New Drug Application for amlo-dipine maleate, or AmVaz as the company branded it, in December, 2001. Dr Reddy's had filed an NDA, and not an ANDA, as it has done for several other patented drugs whose patents in the US had expired or were close to going off-patent, because the key ingredient of AmVaz, amlodipine maleate, had one salt different from Pfizer's Norvasc, a $2 billion anti-hyptension drug. Norvasc's key ingredient is amlodipine besylate. The NDA under Section 505 (b) (2) of the U S Fede-ral Food, Drug and Cosmetic Act, because of this difference in the salt. Dr Reddy's made the filing with Para IV certification on the two Orange Book patents listed for Norvasc. Pfizer filed a lawsuit against Dr Reddy's in June 2002, claiming that AmVaz infringed its patent. Dr Reddy's filed a motion to dismiss Pfizer's. Argument in Dr Reddy's motion was heard on December 11, 2002. The court dismissed Pfizer's complaint on December 17, stating that the patent term extension did not cover amlodipine maleate, following which Pfizer went on appeal. Meanwhile, the USFDA, which had given an "approvable" letter for AmVaz in October 2002, gave the drug "final" approval in Novem-ber last year. However, earlier this month, the FDA said it would be re-evaluating its review of AmVaz. But with the appeals court's ruling, that issue now becomes moot. Clearly wanting to cover all its bases, Dr Reddy's has also filed an ANDA for amlodipine besylate with a Para IV certification with the FDA. Pfizer has filed a lawsuit against the move.