For the second time in as many weeks, FDA has asked interested parties to submit comments regarding 180-day generic drug exclusivity issues. On September 26, as FDA Law Blog reported, FDA requested comments on exclusivity for generic Precose (acarbose) tablets; last week, FDA asked for comments on exclusivity for generic Altace (ramipril) capsules. Two letters have been submitted so far.
Hyman, Phelps & McNamara, P.C. submitted a letter on behalf of an unnamed company that has a tentatively approved ANDA for ramipril capsules. Their letter explains: Cobalt Pharmaceuticals was the first ANDA filer and, as such, was eligible for 180-day exclusivity; Cobalt's ANDA was submitted prior to enactment of the 2003 Medicare Modernization Act, and therefore pre-MMA exclusivity provisions apply; Cobalt's ANDA contained a paragraph IV certification with respect to U.S. Patent No. 5,061,722, a composition of matter patent set to expire in 2008; King and Aventis sued Cobalt for infringing the '722 patent, and later settled the litigation, with Cobalt stipulating to infringement; then, on September 11, 2007, the Federal Circuit invalidated the '722 patent. According to Hyman, Phelps' letter, "Thus, Cobalt's 180-day exclusivity is 'parked' to the detriment of subsequent ANDA applicants with tentative approval (unless and until a court decision triggers exclusivity)."
Hyman, Phelps argues that FDA should determine that Cobalt's ANDA no longer contains a paragraph IV certification, but contains a paragraph III certification instead (based on the fact that Cobalt has stipulated to infringement and therefore is no longer challenging the '722 patent), and so is ineligible for 180-day exclusivity. Moreover, they argue that as soon as the Federal Circuit issues the mandate from its September 11 decision, FDA should remove the '722 patent from the Orange Book (because it will have been formally declared invalid) and grant final approval to any tentatively approved ANDAs for ramipril capsules.
In the other letter, Buc & Beardsley wrote to FDA on behalf of its client, Lupin Pharmaceuticals, to request immediate approval of Lupin's ANDA for ramipril capsules. Lupin is the party that prevailed over King and Aventis in the Federal Circuit on September 11. Like Hyman, Phelps' letter, Buc & Beardsley's letter argues that Cobalt's ANDA no longer contains a valid paragraph IV certification, because Cobalt stipulated to infringement. But unlike Hyman, Phelps', Buc & Beardsley argues that final approval of other ANDAs need not await issuance of a mandate. Instead, based on a fine distinction from the amlodipine case, Buc & Beardsley argues that Lupin's ANDA must be finally approved immediately.
The last point may become moot, since the Federal Circuit may in fact issue a mandate from its September 11 decision before FDA decides all the exclusivity issues raised in these letters.