Round Two: Method of Treatment Claims Survive Another § 101 Challenge – Reargument Denied in Pernix Ireland Pain DAC v. Alvogen Malta Operations Ltd

The U.S. District Court for the District of Delaware denied a motion  for reargument sought by Alvogen Malta Operations Ltd. (Alvogen) in their dispute against Pernix Ireland Pain DAC and Pernix Therapeutics, LLC, (collectively Pernix) regarding the subject matter eligibility of Pernix’s patents under 35 U.S.C § 101 (§ 101).

Alvogen asserted that, in denying summary judgment, the court misapprehended the claims at issue, and had failed to individually analyze some of the claims.

Background
We previously reported on the opinion denying summary judgment.   In the motion for reargument, Alvogen asserted that the claims fall into two categories and the court failed to appreciate the distinction between them.

The first category of claims recite a method of treating pain in certain hepatically impaired patients “using an oral dose of an extended release of hydrocodone bitartrate as the only active ingredient, wherein the starting dose is the same as it would be for a non-hepatically impaired subject.”  The first category of claims is referred to as the “non-adjustment” claims.

The second category of claims recite an extended release formulation with hydrocodone bitartrate as the only active ingredient, and specify that “the dosage provides a release profile of hydrocodone that is defined by designated pharmacokinetic factors, as compared to the release profiles in subjects not suffering from renal or hepatic impairment.” The second category of claims is referred to as the “PK-only” claims.

Order Denying Reargument
In its order denying the motion for reargument, the court stated that it was aware of the difference between the claims, and that it was correct when it previously held that like Vanda, “the claims asserted in this case describe a specific dosing regimen to treat a specific condition based on the patient’s medical status.” Although the term “dosing regimen” typically refers to the amount and frequency of the dosage of a drug, the asserted claims put forth dosing regimens in an unconventional manner.  The claims provide dosing regimens for the non-adjustment claims by defining the dosing level “for hepatically impaired subjects… as being the same as the dosing level used for normal subjects.”  The claims provide dosing regimens for the “PK-only” claims by designating the dosing level for hepatically impaired subjects by “the level that results in specific pharmacokinetic results, as compared to the results obtained in subjects not suffering from renal or hepatic impairment.”

Importantly, the court explained that the claims do not need to recite “specific dosage amounts and frequencies of administration” to be patent eligible.  According to the court’s order, the “PK-only” claims were eligible under § 101 by simply reciting “a method for treating pain in subjects with mild or moderate hepatic impairment comprising administering an oral dosage of hydrocodone bitartrate as the only active ingredient, wherein the dosage unit comprises an extended release formulation of hydrocodone bitartrate.”  The court reasoned that adding more limitations to a claim directed toward eligible subject matter does not make the claim patent ineligible.

Alvogen analogized the claims to those in Mayo  and distinguished the claims from those in Vanda.  But the court did not agree.  According to the court, all of the claims at issue were “‘treatment steps’—that is, directed at a new and useful method of treating pain in a certain population of patients using a specific set of hydrocodone bitartrate formulations.”  For this reason, the court found the claims to be directed toward patent eligible subject matter under § 101.

Finally, Alvogen argued that § 101 analysis requires a consideration of the claimed advance over the prior art and that there should not be a per se rule that all method of treatment claims are patent eligible.  The court stated that it was not adopting a per se rule that all method of treatment claims are patent eligible, but noted that the § 101 analysis does not contain a “strong novelty inquiry.” It was sufficient, for § 101 purposes, that the claims were directed toward a new way of using an existing drug, i.e., “by treating a special subpopulation of patients with a limited genus of formulations of a particular pharmaceutical.”

By Aaron Morrow, Chris Roberts and Margaux Nair