dissenting.
Because I believe the district court correctly interpreted 35 U.S.C. § 156(b) to limit the patent term to the specific product that was the subject of Food and Drug Administration approval, I dissent. As the court points out, section 156(f) defines a product as a new drug “including any salt or ester of the active ingredient.” What the court fails to consider, however, is that regardless of how a product is defined in section 156(f), to be eligible for a patent term extension, that product must “ha[ve] been subject to a regulatory review period before its commercial marketing or use.” 35 U.S.C. § 156(a)(4). In this case, the product that was subject to regulatory review was amlodipine besylate. It was not merely amlodipine, nor was it amlodipine maleate, the product that Dr. Reddy’s seeks approval to market. As such, the product amlodipine maleate cannot qualify for a patent term extension; it does not comport with the statutory requirements for eligibility.
An extension also does not comport with precedent. In Merck v. Kessler, 80 F.3d 1543, 1547 (Fed.Cir.1996), we held that a patent can be given only one extension regardless of the number of drugs that it may claim were subject to approval. And, in interpreting section 156(b)(1), the section at issue in this appeal, we held that “the restoration period of the patent does not extend to all products protected by the patent but only to the product on which the extension was based.” In this case, the restoration period should apply narrowly to cover only amlodipine besylate.