Mylan Nifedipine XL Exclusivity Forfeited By Settling With Pfizer, Teva Says

Mylan's generic nifedipine extended-release tablets should no longer be eligible for 180-day exclusivity because of the company's patent litigation settlement with Pfizer, Teva told FDA in a citizen petition.

The patent settlement effectively bars all "true generic versions of this drug" from coming to market until either the expiration of the last applicable patent for Pfizer's Procardia XL in 2010, or until there is a qualifying court decision invalidating a nifedipine XL patent, "which could be years away," the Aug. 9 citizen petition states.

Mylan has settled with Pfizer, allowing the generics firm to market an "authorized" generic version of the antihypertensive in 30 mg, 60 mg and 90 mg tablets in exchange for having the suit regarding the 30 mg dose dismissed (¹ ).

Though Mylan has an approved ANDA for the drug, "under the circumstances of this deal, it would make no sense whatsoever for Mylan to market its own nifedipine 30 XL and face the possibility of damages for patent infringement that could far exceed any net income Mylan might receive from such marketing," the petition maintains.

Legally, 180-day exclusivity no longer applies to Mylan, Teva contended, since "through [the] agreed dismissal" of the Pfizer lawsuit, "the basis for Mylan's paragraph IV certification - its challenge to the patent - has disappeared."

A paragraph IV ANDA "by definition, must challenge a blocking patent," Teva explained, and "a generic applicant that has settled with the patent holder in a manner that results in no generic product reaching the market is no longer challenging the patent."

Even if the product were eligible for exclusivity, the petition asserts, the agency "should recognize that the commercial marketing trigger of the 180-day provision...was activated on the day the deal was struck" (March 2), giving an exclusivity expiration date of Aug. 29.

"At the latest," the petition adds, exclusivity should end "180 days after the first commercial marketing" of Mylan's authorized generic in late April, which would put expiration at the end of October.

Teva has an agreement with Biovail to distribute Biovail's nifedipine XL 30 mg and 60 mg tablets, which were tentatively approved on July 24.

One precedent for Teva's argument is Barr's loss of 180-day exclusivity for its generic tamoxifen due to a 1993 settlement with Zeneca.

FDA had granted Barr 180-day exclusivity, but the Washington, D.C. federal court ordered FDA to reverse the decision on grounds that Barr rescinded its paragraph IV certification when it settled (² (Also see "FDA Ordered To Rescind Barr's 180-Day Exclusivity For Generic Tamoxifen" - Pink Sheet, 10 Apr, 2000.)).

Mylan triggered the April ruling by asking the court to grant exclusivity to its generic version of tamoxifen.

Teva is not requesting that exclusivity be transferred to the second nifedipine XL paragraph IV ANDA filer in light of FDA's August 1999 proposed rule's rejection of a rolling exclusivity interpretation of Waxman/Hatch, the company explained.

FDA's proposed rule suggests a 180-day triggering period that would begin when a competing ANDA for the same drug is tentatively approved. To retain exclusivity, the initial ANDA filer either would have to commercially launch the product or win a favorable court decision regarding the patent (³ ).

Teva claimed that "the 180-day exclusivity clause was never intended to create opportunities for drug companies to indefinitely obstruct the market entry of generic drugs by entering into commercial arrangements which, like the Mylan-Pfizer deal, prevent the 180-day period from ever being triggered."

Other types of agreements between generic and brand name manufacturers have recently come under scrutiny by courts and the Federal Trade Commission.

The Detroit federal court ruled in June that an agreement between Andrx and Aventis to provide quarterly payments to Andrx in exchange for not marketing generic diltiazem until the conclusion of patent litigation violated antitrust laws. FTC filed an administrative action against Andrx and Aventis in March (⁴ (Also see "Aventis/Andrx Cardizem CD Deal Violated Antitrust Laws, Judge Says" - Pink Sheet, 12 Jun, 2000.)).