Barr believes that in a worst case scenario it will still have two months of Waxman/Hatch exclusivity for its generic version of Prozac (fluoxetine).

FDA has concluded that Barr's 180-day generic exclusivity should begin immediately upon a final court decision in litigation against Lilly, even though the product cannot come to market until the expiry of Lilly's pediatric exclusivity for Prozac Aug. 2.

The decision that a brand name company's pediatric exclusivity and a generic firm's Waxman/Hatch exclusivity run concurrently rather than consecutively could render at least part of Barr's 180 days unusable.

According to Barr, its 180-day exclusivity for fluoxetine has not yet begun, and will not be triggered until a mandate is issued by the Washington, D.C. federal appeals court and entered with the Indianapolis district court.

A Washington, D.C. federal appeals court decision in August invalidated Lilly's longest-running Prozac patent (¹ Also see "Barr Fluoxetine Generic Exclusivity Claim Faces Hurdles" - Pink Sheet, 28 August, 2000.). The patent that was left standing expired Feb. 2, but pediatric exclusivity runs until August.

Barr believes its generic exclusivity will not be triggered until the appeals court denies Lilly's pending motion for a rehearing. Even if that occurs immediately, there would likely be a two-week delay until a mandate is entered with the district court. Under that scenario, Barr would have about two months of generic exclusivity remaining on Aug. 2.

There could be a further delay in triggering the generic exclusivity if Lilly requests a stay in the entry of the mandate with the district court. Barr and Lilly share an interest in Barr retaining its full 180 days of exclusivity, since price erosion is generally limited until multiple generics enter the market.

Senate Judiciary Committee Chairman Hatch (Utah) wrote two letters - along with pediatric provision sponsors Sens. DeWine (R-Ohio) and Dodd (D-Conn.) - to FDA maintaining that generic exclusivity and pediatric exclusivity periods should not run concurrently (² Also see "Generic/Pediatric Exclusivity Overlap Not Required By Court Rulings - Hatch" - Pink Sheet, 1 January, 2001.).

In a Feb 22 response, FDA Associate Commissioner for Legislation Melinda Plaisier said that "FDA has determined that when pediatric exclusivity has the potential to overlap with 180-day exclusivity triggered by court decision, FDA will nonetheless apply the court decision trigger as written in the 180-day exclusivity provision."

"This necessarily means that in some instances the party that receives the 180-day exclusivity may be blocked from marketing during some or all of the 180-day period while the innovator's pediatric exclusivity runs." The letter follows up on a Jan. 24 meeting between FDAers and staffers of Hatch and DeWine. The Senators expressed their "dismay" with the FDA decision in a March 9 letter to HHS Secretary Thompson.

The January 2000 Mylan v. Shalala ruling specifies that exclusivity should be triggered by a district court decision in a patent case, rather than waiting for a final unappealable decision, FDA noted. The 1998 Mova v. Shalala decision found that generic exclusivity should be awarded to the first generic applicant to file, rather than the first to successfully challenge a patent.

FDA has concluded, "in light of Mova and Mylan, that the statute, as written, did not guarantee that the 180-day period would be of use to the applicant who received it," Plaisier said. The agency noted that the pediatric legislation is silent on the issue.

The agency suggests that Hatch may want to use the reauthorization of the pediatric exclusivity law as a vehicle to address the issue.

"FDA recommends that the most expeditious and effective way to ensure that 180-day and pediatric exclusivity run consecutively is for Congress to enact a targeted legislative fix," the letter states. "Because the pediatric exclusivity provision is scheduled to sunset in January 2002 and because Congress will likely take up its reauthorization in the current legislative session, the reauthorization deliberations provide the ideal forum to address this issue."

During a March 7 meeting sponsored by the Federalist Society, Hatch re-affirmed his position: "In my view, which is also the view of both Sens. DeWine and Dodd, and not contradicted by any other member of Congress as far as I know, the pediatric provision and the 180 days rules should run consecutively, not concurrently," Hatch said.

Barr Fluoxetine Will Have Two Months Exclusivity Under "Worst Case"

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