CHAPTER § 3.01 Using Patents to Protect Pharmaceutical Research

• Jurisdiction: United States

§ 3.01 Using Patents to Protect Pharmaceutical Research

Patents protect the pharmaceutical industry's extensive capital investment in its core asset, drug products. Because competition impacts drug products early in their product life cycle, it is critical for pharmaceutical manufacturers to understand how patents work and how to develop effective patent strategies.

[1] Overview of the Statutory Framework Governing the Patent System and Exclusionary Rights Secured by a Patent Grant

Patent rights emanate from Article I, section 8, clause 8 of the United States Constitution, which gives Congress the power to "promote the Progress of Science and useful Arts, by securing for limited Times to Authors and inventors the exclusive Right to their respective Writings and Discoveries." The majority of Congress' legislative implementation of this power is found in the Patent Act of 1952.¹

A patent granted to an inventor by the United States Patent and Trademark Office ("USPTO") bestows on the owner a property right. Specifically, the patent gives its owner "the right to exclude others from making, using, offering for sale, or selling" the invention in the United States or "importing" the invention into the United States.² This is in contrast to an affirmative right to practice the invention.

In broad terms, an issued patent consists of two main parts: the "claims" and the "specification." Like a fence marking the boundaries of real property, the patent claims define the scope of the protected invention and give the public notice of what the patentee defines as his invention. In an issued patent, the claims are found at the end of the document, beginning with the text "I claim" or "We claim," followed by the numbered paragraphs setting out the claims. The specification describes the invention in various ways required by statute and may include one or more examples or drawings.

Under 35 U.S.C § 101, an inventor can obtain patent protection for "any new and useful process, machine, manufacture, or composition of matter, or any new and useful improvement thereof," subject to the conditions and requirements of the law. Of primary importance in the pharmaceutical industry are patents covering composition of matter, "processes," or "methods."

The U.S. Supreme Court has defined "composition of matter" to mean "all compositions of two or more substances and all composite articles, whether they be the results of chemical union, or of mechanical mixture, or whether they be gases, fluids, powders or solids."³

A "process" is defined by statute as any "process, act or method," and includes a new use of a known process, machine, manufacture, composition of matter or material.⁴ Process claims include, for example, methods of synthesizing, purifying, and compounding pharmaceutical products, as well as methods of medical treatment, testing with such products, and methods of screening to identify the same. Protection also may be available for products according to the process by which they are made ("product-by-process" protection).⁵

Historically, the Supreme Court has construed Section 101 broadly, holding that "Congress plainly contemplated that the patent laws would be given wide scope."⁶ At best, judicial exceptions were recognized for "laws of nature, physical phenomena, and abstract ideas."⁷ "While these exceptions are not required by the statutory text, they are consistent with the notion that a patentable process must be 'new and useful.'"⁸ Yet, new technologies have challenged the existing legal framework, and the Supreme Court has taken a less pro-patent stance in the last 15 years.

In Mayo v. Prometheus, a unanimous Supreme Court held that method claims reciting a correlation between naturally occurring metabolites and drug efficacy or toxicity were unpatentable under Section 101.⁹ Specifically, the Court found that (i) the claim was focused on the correlation, which represented a law of nature given that the hand of man has nothing to do with the interaction of the body with the compound and (ii) the recited steps involved nothing more that "well-understood, routine and conventional activity" in the art.¹⁰ The Court further explained that while the "administering," "determining," and "wherein" steps were not themselves natural laws, they were not sufficient to transform the nature of the claim.¹¹ The Federal Circuit also handed down several decisions invalidating diagnostic method patents under Section 101 in the wake of Mayo.¹²

In Association for Molecular Pathology v. Myriad Genetics, Inc., a unanimous Supreme Court held that claims to isolated, naturally occurring human genes were unpatentable under Section 101.¹³ The decision effectively invalidated thousands of human gene patents previously granted in the United States and raised questions as to whether other naturally occurring molecules (proteins, small molecules) might be found similarly ineligible. However, the Court specifically limited their ruling to naturally occurring DNA while cDNA made from naturally occurring mRNA would remain patentable.¹⁴

The Supreme Court and Federal Circuit explained the decisions in Mayo and Myriad as establishing a two-part test.¹⁵ Under the first step, the court must "determine whether the claims at issue are directed to a patent-ineligible concept."¹⁶ Under the second step, the court "must examine the elements of the claim to determine whether it contains an inventive concept sufficient to transform the claimed [patent-ineligible concept] into a patent-eligible application."¹⁷ The Federal Circuit has clarified that "it is not enough [at Mayo's step one] to merely identify a patent-ineligible concept underlying the claim; we must determine whether that patent-ineligible concept is what the claim is directed to."¹⁸

In the wake of these decisions, the USPTO issued a series of guidelines to assist patent examiners in determining what constitutes ineligible subject matter under Section 101.¹⁹ To the detriment of patent applicants, the guidelines significantly expanded upon the holdings of Mayo and Myriad. For example, the May 2016 guidelines state that isolated, naturally occurring molecules other than DNA (e.g., small molecules) are not considered patentable subject matter unless the claim contains an additional element, or combination of elements, sufficient to ensure that the claim amounts to significantly more than the natural molecule itself.²⁰ While the guidelines do not have the force of law, they impacted the nature of patents issuing from the USPTO thereafter.

However, more recent Federal Circuit decisions suggest that the pendulum is swinging back in favor of patent owners. In Vanda Pharmaceuticals Inc. v. West-Ward Pharmaceutical, a divided panel of the Federal Circuit found claims eligible under Section 101 requiring the steps of "(1) determining the patient's CYP2D6 metabolizer genotype by (a) obtaining a biological sample and (b) performing a genotyping assay; and (2) administering specific dose ranges of iloperidone depending on the patient's CYP2D6 genotype."²¹ According to the defendant, the claims were directed to patent-ineligible subject matter under Section 101 "because they are directed to a natural relationship between iloperidone, CYP2D6 metabolism, and QT prolongation, and add nothing inventive to those natural laws and phenomena."²² But the Court distinguished the Vanda claims from the claim at issue in Mayo on the grounds that the former were "directed to" a method of treatment under Mayo's step one, while the latter was directed to a diagnostic method without steps of "prescribing a specific dosage regimen or other added steps to take as a result of that indication."²³ The Federal Circuit also noted that the Supreme Court's decision in Myriad "was careful to note that 'method claims' and 'patents on new applications of knowledge about [particular] genes' were 'not implicated by [its] decision.'"²⁴

In Berkheimer v. HP Inc., the Federal Circuit found that while subject-matter eligibility is ultimately a question of law, factual questions can exist about whether claims are directed to judicial exception-making it more difficult for defendants to challenge validity on the basis of Section 101 early in litigation.²⁵ In 2019, the USPTO followed the Federal Circuit's lead in issuing more liberal guidelines for subject matter eligibility under Section 101.²⁶ Specifically, the January 2019 USPTO guidelines explain that a claim that recites a judicial exception is not "directed to" the judicial exception if the judicial exception is "integrated into a practical application"

[2] Statutory Considerations in Drafting Pharmaceutical Patents

To be patented in the United States, an invention must be useful, novel, and non-obvious.²⁷

Under 35 U.S.C. § 101, an invention is "useful" if it provides some identifiable benefit and is capable of use.²⁸ Generally, utility is a low hurdle for patent applicants. However, the utility must be specific to the subject matter claimed and can "provide a well-defined and particular benefit to the public," i.e., a substantial utility.²⁹ For example, a claim to a polynucleotide whose use is disclosed simply as a "gene probe" or "chromosome marker" would not be considered to be specific in the absence of a disclosure of a specific DNA target.³⁰

Under 35 U.S.C. § 103, a claimed invention must be novel to be patented, i.e., the invention cannot have been known before the filing date of the priority patent application. A prior art reference cannot defeat the novelty of a patent claim if the reference does not disclose all claimed features, either objectively or inherently.³¹ Examiners with the USPTO rely on inherency arguments to challenge patent claims when a single prior art reference cited for novelty (anticipation) contains an incomplete description of the subject matter at issue. A prior art reference must also disclose the claim elements "arranged as in the claim."³² Under certain circumstances...