Allergan V. Sandoz Emphasizes Importance Of Prosecution History In Construing “Wherein” Clauses

September 27, 2019 | US Law Updates, US Law Updates - Featured

By Dr. Jayashree Mitra and Brian Beck

Claim Construction of “Wherein” Clause May Be Contingent On Prosecution History

The Federal Circuit’s recent decision in Allergan Sales, LLC v. Sandoz, Inc., No. 2018-2207 (Fed. Cir. Aug. 29, 2019) (“Allergan”) illustrates how arguments made during prosecution with regards to the term “wherein” can turn the tide on invalidity arguments at trial. The decision also serves as a reminder that commonly used claim terms can be critical in determining the fine line between validity and invalidity at trial.

The representative claim in Allergan was a method-of treatment claim where the use of the combination brimonidine-timolol product was further defined in terms of increased efficacy and reduced adverse effects when compared with brimonidine treatment alone:

A method of treating a patient with glaucoma or ocular hypertension comprising

topically administering twice daily to an affected eye a single composition comprising 0.2% w/v brimonidine tartrate and 0.68% w/v timolol maleate,

wherein the method is as effective as the administration of 0.2% w/v brimonidine tartrate monotherapy three times per day and

wherein the method reduces the incidence of one o[r] more adverse events selected from the group consisting of conjunctival hyperemia, oral dryness, eye pruritus, allergic conjunctivitis, foreign body sensation, conjunctival folliculosis, and somnolence when compared to the administration of 0.2% w/v brimonidine tartrate monotherapy three times daily.

The Federal Circuit had previously held that claims to the composition combining brimonidine and timolol were invalid as obvious.

During claim construction arguments before the district court, Sandoz argued that the “wherein” clauses did not limit the claim but only stated the intended result of the invention. If the “wherein” clauses were not limiting, then the claim would be invalid as obvious as it would be limited to the composition alone, which the Federal Circuit had previously found to be obvious.

The District Court disagreed, holding that the specification emphasized the benefits of the combination as satisfying a need to improve efficacy without increasing adverse effects, and that Allergan had relied on those disclosures during prosecution to overcome prior art.

The Federal Circuit affirmed.

Practice Pointers

In upholding the District Court’s analysis, Federal Circuit distinguished its own precedent with regards to “wherein” and “whereby” clauses, finding that in those instances where the clause was not a claim limitation, the clause was neither necessary or relevant to the examiner’s approval.

This is not inconsistent with the majority of cases where a “wherein” clause stating the purpose or results of an otherwise fully defined invention is held to not limit the claim. However, as Chief Judge Prost noted in a concurrence, “[g]iven the specificity, clarity, and material limits the ‘wherein’ clauses add to the scope of claim 1 on their face,” Sandoz’s position that the “wherein” clauses did not limit the claim “deserve[d] rigorous scrutiny from the start.”

Allergan thus serves as a reminder that a patent claim that includes a statement of purpose or intended results, that in other contexts may not be the subject of dispute, must always be considered in the context of that particular claim and be evaluated to assess whether it is relevant to the scope of the claim.

About Dr. Jayashree Mitra:

Partner, Zuber Lawler

Dr. Jayashree Mitra has years of experience in the different facets of the pharmaceutical industry.  She has been involved in basic bench research, evaluated the progress of a compound through regulatory approvals, marketed and positioned the drug in the marketplace and litigated the associated patents.  She has represented major pharmaceutical companies in Hatch-Waxman litigation, 505(b)(2) applications, and in IPR and PGR proceedings.  She has also represented pharmaceutical companies in antitrust actions involving claims of Walker-Process fraud, reverse payment claims, claims under Sherman Act and state antitrust and consumer protection actions.  Dr. Mitra has a Ph.D in pharmacology from Yale and a J.D. from Northwestern School of Law, where she was a member of Law Review.

About Brian Beck:

Associate, Zuber Lawler 

Brian Beck is a patent and commercial litigator with extensive experience in technologies including pharmaceutical manufacturing processes, mechanical devices, software, and business methods. His previous representations include successful defenses of trade secret lawsuits concerning manufacturing processes for extended release liquid pharmaceutical formulations and transdermal formulations, representation of a French biotechnology company in patent litigation concerning gene editing techniques, and representation of a plaintiff pharmaceutical company in patent and trademark litigation concerning nutritional supplement compositions. He is also a registered patent attorney who has represented clients in the inter partes proceedings before the USPTO. He earned his J.D. from New York School of Law and his B.S. from Princeton University, where he majored in mechanical and aerospace engineering.

About Zuber Lawler:

Zuber Lawler focuses on intellectual property, deals, IPO’s, regulatory work and litigation. The firm manages matters for clients throughout the world from offices in Chicago, Denver, Los Angeles, New York, Phoenix, and Silicon Valley. Zuber Lawler represents a long list of Fortune companies, global funds and government entities. Zuber Lawler’s attorneys work in languages covering 90% of the world’s population.