Subsequent ANDA Sponsor Says DETROL LA Patent Has Gotta Go; But Would a Final Court Decision Trigger 180-Day Exclusivity?

February 10, 2011

By Kurt R. Karst –      

Late last year, Impax Laboratories, Inc. (“Impax”) filed a Complaint in the U.S. District Court for the District of New Jersey seeking a judgment with respect to U.S. Patent No. 6,911,217 (“the ‘217 patent”).  The ‘217 patent is one of four patents listed in the Orange Book for Pfizer, Inc.’s (“Pfizer’s”) DETROL LA (tolterodine tartrate) Extended Release Tablets, 4mg and 2mg.  (The other patents are U.S. Patent Nos. 5,382,600 (“the ’600 patent”), 6,630,162 (“the ‘162 patent”), and  6,770,295 (“the ‘295 patent”), which expire on March 25, 2012, November 11, 2019, and August 26, 2019, respectively, but are each subject to a 6-month period of pediatric exclusivity.)  Impax’s Complaint requests that the court rule that the company’s proposed generic version of DETROL LA, which is the subject of ANDA No. 90-235 containing a Paragraph IV certification to each of the four Orange Book-listed patents, does not infringe any claim of the ‘217 patent. 

Impax, which is apparently not a first applicant eligible for 180-day exclusivity – FDA’s Paragraph IV Certification List says that the first ANDA containing a Paragraph IV certification for an Orange Book-listed patent covering DETROL LA was received as of July 30, 2007 – was sued a few years back based on the company’s Paragraph IV certifications to the ‘600, ‘162, and ‘295 patents, but was not sued on the ‘217 patent.  Pfizer subsequently granted Impax a covenant not to sue with respect to the ‘217 patent.  According to Pfizer’s recent Motion to Dismiss the Impax Complaint, which argues for dismissal based on, among other things, a lack of subject matter jurisdiction, another company is the only first applicant eligible for 180-day exclusivity. 

There has been quite a bit of patent infringement litigation over the DETROL LA Orange Book patents involving various ANDA sponsors.  We will not get into that here.  The bottom line is that with its declaratory judgment action, Impax is attempting to create a court decision to trigger 180-day exclusivity under the failure-to-market forfeiture provisions at FDC Act § 505(j)(5)(D)(i)(I).  Notably, however, FDA has not tentatively approved any ANDA for a generic version of DETROL LA.  While that does open the door to a possible forfeiture of 180-day exclusivity under FDC Act § 505(j)(5)(D)(i)(IV) for failure to obtain tentative approval within 30 months of ANDA submission, it also raises questions about the circumstances under which a subsequent ANDA sponsor can trigger a first applicant’s 180-day exclusivity.

Under the 180-day exclusivity failure-to-market forfeiture provisions at FDC Act § 505(j)(5)(D)(i)(I), there must be two events, or “bookends,” to calculate a “later of” event between items (aa) and (bb).  The first bookend date under item (aa) is the earlier of the date that is:

(AA) 75 days after the date on which the approval of the application of the first applicant is made effective under subparagraph (B)(iii); or

(BB) 30 months after the date of submission of the application of the first applicant

The other bookend – the (bb) part of the equation – provides that the (bb) date is “the date that is 75 days after the date as of which, as to each of the patents with respect to which the first applicant submitted and lawfully maintained a [Paragraph IV] certification qualifying the first applicant for the 180-day exclusivity period,” one of three events occurs:

(AA) In an infringement action brought against that applicant with respect to the patent or in a declaratory judgment action brought by that applicant with respect to the patent, a court enters a final decision from which no appeal (other than a petition to the Supreme Court for a writ of certiorari) has been or can be taken that the patent is invalid or not infringed.

(BB) In an infringement action or a declaratory judgment action described in [FDC Act § 505(j)(5)(D)(i)(I)(bb)(AA)], a court signs a settlement order or consent decree that enters a final judgment that includes a finding that the patent is invalid or not infringed.

(CC) The patent information submitted under [FDC Act § 505(b) or (c)] is withdrawn by the holder of the application approved under subsection (b).

The (AA) and (BB) court decision events under item (bb) can be triggered in patent infringement litigation by “the first applicant or any other applicant (which other applicant has received tentative approval)” (emphasis added).  

FDA has not yet, to our knowledge, addressed the “which other applicant has received tentative approval” parenthetical at FDC Act § 505(j)(5)(D)(i)(I)(bb).  What is not clear from the statute is whether the order of events counts.  It seems there are three possibilities with respect to a subsequent applicant who obtains tentative approval:

The first possibility is if a subsequent applicant first obtains tentative approval and then a final court decision in its favor.  Under this scenario, the statute seems clear that the 75-day period under (bb) begins on the date of that final court decision.  The first applicant’s 180-day exclusivity would be forfeited 75 days later (provided there is an (aa) event), unless a first applicant commercially markets before the 75-day date. 

Indeed, this was the case with FDA’s recent approval of Teva’s ANDA No. 77-983 for a generic version of Lilly’s GEMZAR (gemcitabine for injection), 1 gram/Single-use Vial & 200 mg/Single-use Vial.  As a first applicant, Teva qualified for 180-day exclusivity.  Another, subsequent ANDA sponsor, Sun Pharmaceuticals, obtained tentative approval for its ANDA No. 78-433 on March 4, 2008.  Sun was involved in patent infringement litigation with Lilly with respect to a patent on which Teva qualified for 180-day exclusivity.  The district court ruled in Sun’s favor, and Lilly appealed to the U.S. Court of Appeals for the Federal Circuit.  In July 2010, a panel of Federal Circuit judges affirmed the district court decision.  Lilly petitioned the Court for a panel rehearing/rehearing en banc, which the Court denied on November 1, 2010.  On November 12, 2010, the Federal Circuit issued its mandate, and Lilly has reportedly now petitioned the U.S. Supreme Court to review the decision.  FDA considered the date of issuance of the mandate to be a final court decision for purposes of triggering the 75-day clock under FDC Act § 505(j)(5)(D)(i)(I)(bb).  The date that was 75 days after November 12, 2010, and the date a forfeiture of 180-day exclusivity would have occurred was January 26, 2011.  However, FDA approved ANDA No. 77-983 on January 25, 2011 – one day short of the 180-day exclusivity forfeiture date.

A second possibility is if the subsequent applicant first obtains a final court decision in its favor and then tentative approval.  Under this scenario, it is unclear when the 75-day period begins.  FDA could interpret the statute such that the 75-day period is retroactive to the date of the final court decision.  Alternatively, FDA could interpret the statute such that the 75-day period begins on the date on which the subsequent applicant completed the statutory criteria.  That is, the 75-day period would begin on the date the subsequent applicant obtains tentative approval. 

Finally, under a third scenario, a subsequent applicant could, as under the second scenario, first obtain a final court decision in its favor and then tentative approval.  But instead of triggering the 75-day date, FDA could interpret the statute such that the final court decision does not trigger the 75-day period.  Under this interpretation, the order of events is critical.  That is, for the 75-day period to be triggered, a subsequent applicant must have tentative approval at the time there is a final court decision.  If not, then under this interpretation, the a final court decision has no effect and there is not a (bb) bookend event to cause a forfeiture of 180-day exclusivity.    

So how does all of this tie into Impax’s declaratory judgment action concerning DETROL LA?  At this time, FDA has not tentatively approved Impax’s ANDA (or any other ANDA).  Admittedly, a final court decision may be far off, during which time FDA could very well grant tentative approval.  However, with what appears to be a growing  number of declaratory judgment actions to trigger 180-day exclusivity (see, e.g., here and here), the chances also grow that a final court decision could come at a time before FDA has granted tentative ANDA approval.