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Nalproprion v. Actavis: WDR met by Substantially Equivalent Claim Elements(?)

In Nalproprion v Actavis, App. No. 2018-1221 (Fed. Cir., August 15, 2019) a divided panel of Judges Prost, Lourie and Wallach – Prost dissenting – affirmed the district court’s ruling that claim 11 of U.S. Pat. No. 8,916,195 met the written description requirement of 35 U.S.C. 112(a). Claim 11 follows:

11. A method of treating overweight or obesity having reduced adverse effects comprising orally administering daily about 32 g of naltrexone and about 360 mg of bupropion…to a person in need thereof, wherein the bupropion … is administered as a sustained release formulation, wherein the naltrexone … is administered as a sustained release formulation [that] has an in vitro naltrexone dissolution rate in a dissolution test of USP Apparatus 2 Paddle Method at 100 rpm in a dissolution medium of water at 37 degrees C. [“USP 2”]of:          (a) betweeen 39% and 76% of naltrexone released in one hour;                                                    (b) between 62% and 90% of naltrexone released in 2 hrs; and                                                    (c) at least 99% was in 8 hrs;                                                                                                                  wherein [dosing parameters].

The controversial part of this claim is the words between “in vitro” and “8 hrs”. The dispute between the parties and between Judges Lourie and Wallach and Judge Prost turned on whether or not the specification adequately described the invention set forth in claim 11. The dissolution rate recited in the claim on Table 10 matched the rate recited in the claim but did not disclose if USP 2 or a somewhat differed in vitro test, USP 1, was used. Test USP 2 is described in the specification at Col. 6 – lines 45-55.

At first, this seemed like it should have been a straightforward analysis. I always thought that the specification comprised the disclosure and the claims. Section 112(a) states that the specification shall contain the written description of the invention. Does this mean that originally-filled claims cannot meet the WDR on their own? Not according to Fed. Cir. precedent: “Original claims are part of the specification and in many cases will satisfy the [WDR]”, Crown Packaging Tech., Inc. v. Ball Metal Beverage Container Corp., 635 F.3d 1373, 1380 (Fed. Cir. 2011).

So, if claim 11 was an originally filed claim, why is this a 28 page decision with a dissent? Claim 11 very clearly sets forth an invention that is clearly described, whether or not it is set forth in the same words in the specification. It seems this should be an easy case to affirm.

I did not have time to review the prosecution history of this lengthy patent, and only fragments are in the opinion, but let’s assume, as Actavis argued, that claim 11 was amended so that it stuck the dissolution data from Table 10 onto the USP 2 methodology to arrive at claim 11. The central problem that the Judges addressed is that there is no disclosure of how the data in Table 10 was obtained.

The district court concluded that expert testimony convinced it that “a person of ordinary skill would recognize that the inventors possessed an embodiment of the invention as described in Table 10, regardless of whether USP 2 or “‘a substantially equivalent’ method” was used. The majority of the panel agreed.

They gave weight to the fact that the dissolution data in the claim “relates only to the measurement of resultant in vitro parameters, not to the operative steps to treat overweight or obesity.” In other words, the majority is downgrading some of the claim elements in favor of the dosing regimen parts of the claim. No case law is cited to support this bifurcation of the claim or why it was appropriate to use this approach to permit the claim to satisfy the WDR.

The majority noted that Actavis’ expert was caught in a Catch 22 when he testified that USP 1 and USP 2 would yield different solubility profiles, but later testified that claim 11, that recites USP 2 was obvious in view of a reference that used USP 1.

Judge Prost’s dissent focused on the issues discussed above, arguing that the patent’s Applicants stressed the importance to the dissolution profile that resulted from the USP 2 analysis:

“As the USP 2-clause is limiting and the original patent disclosure fails to literally or inherently disclose it, the [WDR] inquiry should end there….Such a conclusion problematically  articulates a new rule for [WDR]”…according to the majority, written description for non-limiting clauses may be satisfied by disclosure that is ‘substantially equivalent” even though the same disclosure would not be sufficient for limiting clauses.”


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