2751 Eligibility Requirements [R-01.2024]

35 U.S.C. 156(a) sets forth what patents can be extended and the conditions under which they may be extended. 37 CFR 1.710 also addresses the patents that may be extended, and 37 CFR 1.720 describes the conditions under which a patent may be extended. As set forth in 35 U.S.C. 156 and 37 CFR 1.710, a patent which claims a human drug product, medical device, food or color additive first approved for marketing or use after September 24, 1984, or an animal drug or veterinary biological product (which was not primarily manufactured through biotechnology) first approved for marketing or use after November 16, 1988, may qualify for patent term extension. Furthermore, 35 U.S.C. 156(a)(1)-(5) require that the applicant establish that:

• • (1) the patent has not expired before an application under 35 U.S.C. 156(d) was filed (this may be an application for patent term extension under subsection (d)(1) or an application for interim extension under subsection (d)(5));
• • (2) the patent has never been extended under 35 U.S.C. 156(e)(1);
• • (3) the application for extension is submitted by the owner of record of the patent or its agent to the Office within 60 days of regulatory agency approval of the commercial marketing application and the application includes details relating to the patent, the approved product, and the regulatory review time spent in securing regulatory agency approval;
• • (4) the product has been subject to a regulatory review period within the meaning of 35 U.S.C. 156(g) before its commercial marketing or use;
• • (5) the approval is the first permitted commercial marketing or use of the product (35 U.S.C. 156(a)(5)(A)), except in the case of human drug products manufactured using recombinant DNA technology where the provisions of 35 U.S.C. 156(a)(5)(B) apply, or in the case of a new animal drug or a veterinary biological product where the provisions of 35 U.S.C. 156(a)(5)(C) apply.

35 U.S.C. 156(c)(4) also requires that no other patent term has been extended for the same regulatory review period for the product. See MPEP § 2761.

I. TERMINALLY DISCLAIMED PATENTS ARE ELIGIBLE

A patent may be extended under 35 U.S.C. 156, even though it has been terminally disclaimed. A patent term extension under 35 U.S.C. 156 is a limited extension of the patent rights associated with the approved product that is attached onto the original term of the patent. See 35 U.S.C. 156(b). Only one patent may be extended for a regulatory review period for any product, and 35 U.S.C. 156 sets the expiration date of a patent term extension. Although 35 U.S.C. 154(b)(2) (June 8, 1995) precludes a patent from being extended under 35 U.S.C. 154(b) if the patent has been terminally disclaimed due to an obviousness-type double patenting rejection (see MPEP § 2720), there is no such exclusion in 35 U.S.C. 156. Additionally, 35 U.S.C. 154(b)(2)(B)) (May 29, 2000) provides that a patent cannot be adjusted beyond the date set by the disclaimer (see MPEP § 2730), but there is no similar provision in 35 U.S.C. 156. Thus, patents may receive a patent term extension under 35 U.S.C. 156 beyond an expiration date set by a terminal disclaimer. See Merck & Co., Inc. v. Hi-Tech Pharmacal, Co., Inc., 482 F.3d 1317, 82 USPQ2d 1203 (Fed. Cir. 2007). For the impact of PTE on double patenting, see MPEP § 804.05.

A patent term extension under 35 U.S.C. 156 “is valid so long as the extended patent is otherwise valid without the extension.” Novartis AG v. Ezra Ventures LLC, 909 F.3d 1367, 1375, 128 USPQ2d 1752 (Fed. Cir. 2018). Therefore, obviousness-type double patenting cannot be used to negate patent term extension under 35 U.S.C. 156 when the potential reference patent could not have been used to challenge the unextended term of the patent that received the extension.

II. MEANING OF “PRODUCT” AS DEFINED IN 35 U.S.C. 156(f)

As required by 35 U.S.C. 156(a), patents eligible for extension of patent term are those which:

• (A) claim a “product” as defined in 35 U.S.C. 156(f)(1), or a method of using such a product, or a method of manufacturing such a product, and
• (B) meet all other conditions and requirements of the statute.

The term “claims a product” is not synonymous with “infringed by a product.” A patent which claims a metabolite of an approved drug does not claim the approved drug. Hoechst-Roussel Pharmaceuticals Inc. v. Lehman, 109 F.3d 756, 759, 42 USPQ2d 1220, 1223 (Fed. Cir. 1997). Where extension of a patent is sought based upon regulatory review under section 515 of the Federal Food Drug and Cosmetic Act of a medical device, the patent claims must include some physical structure of a device in order for the patent to be said to claim the product (or a method of using the product) thereby rendering the patent eligible for extension. Angiotech Pharms. Inc. v. Lee, 191 F. Supp. 3d 509 (E.D. Va. 2016).

The term “product” means:

• (A) The active ingredient of a new human drug, antibiotic drug, or human biological product (as those terms are used in the Federal Food, Drug, and Cosmetic Act and the Public Health Service Act) including any salt or ester of the active ingredient, as a single entity or in combination with another active ingredient; or
• (B) The active ingredient of a new animal drug or veterinary biological product (as those terms are used in the Federal Food, Drug, and Cosmetic Act and the Virus-Serum-Toxin Act) that is not primarily manufactured using recombinant DNA, recombinant RNA, hybridoma technology, or other processes including site specific genetic manipulation techniques, including any salt or ester of the active ingredient, as a single entity or in combination with another active ingredient; or
• (C) Any medical device, food additive, or color additive subject to regulation under the Federal Food, Drug, and Cosmetic Act.

See 21 CFR 60.3(b) for definitions of terms such as active ingredient, color additive, food additive, human drug product, and medical device.

Essentially, a “product” is a “drug product,” medical device, food additive, or color additive requiring Food and Drug Administration or Department of Agriculture (Animal and Plant Health Inspection Service) approval of an order or regulation prior to commercial marketing or use. “Drug product” is further defined as the active ingredient of a human drug, animal drug (excluding those primarily manufactured using recombinant DNA, recombinant RNA, hybridoma technology, or other processes including site specific genetic manipulation techniques), or biological product (as defined by the Federal Food, Drug and Cosmetics Act and the Public Health Service Act) including any salt or ester of the active ingredient, as a single entity or in combination with another active ingredient. “The active ingredient of a given drug product is defined by what is approved and is specified on the drug's label.” Biogen Int’l GmbH v. Banner Life Scis. LLC, 956 F.3d 1351, 1356, 2020 USPQ2d 10385 (Fed. Cir. 2020) (citing 21 U.S.C. 352(e)(1)(A)(ii) and 21 CFR 201.100(b)(4)).

A “drug product” means the active ingredient found in the final dosage form prior to administration of the product to the patient, not the resultant form the drug may take after administration. See Hoechst-Roussel, 109 F.3d at 759 n.3 (“For purposes of patent term extension, this active ingredient must be present in the drug product when administered.”). In addition, a patent to a drug product having one form of an active ingredient may qualify for an extension even though another form of the underlying chemical moiety was previously approved and commercially marketed or used. For example, a drug product having the ester form of a particular chemical moiety is a different drug product from the same chemical moiety in a salt form, even though both the salt and the ester are used to treat the same disease condition by the same mechanism. See PhotoCure v. Kappos, 603 F.3d 1372, 95 USPQ2d 1250 (Fed. Cir. 2010); see also Glaxo Operations UK Ltd. v. Quigg, 894 F.2d 392, 13 USPQ2d 1628 (Fed. Cir. 1990) (holding that a patent which claimed an ester of the acid cefuroxime was eligible for extension regardless of previous approvals of two salts of cefuroxime). Similarly, a deesterified version of an approved drug product having the same active moiety is not the same drug product under 35 U.S.C. 156(f). Biogen Int’l GmbH v. Banner Life Scis. LLC, 956 F.3d 1351, 2020 USPQ2d 10385 (Fed. Cir. 2020). Thus, eligibility for patent term extension for a patent which claims a product subject to regulatory review as set forth in 35 U.S.C. 156(g) turns on the question of whether the product, i.e., the active ingredient of the drug product, present in the final dosage form was previously approved by FDA, as required by 35 U.S.C. 156(a)(5)(A). If neither the active ingredient of the drug product, nor any salt or ester of that active ingredient has been previously approved by FDA, then the approval of the product complies with 35 U.S.C. 156(a)(5)(A) and a patent claiming such a product, a method of using such a product or a method of manufacturing such a product should be eligible for patent term extension.

Furthermore, a “drug product” is the active ingredient of a particular new drug, rather than the entire composition of the drug product approved by the Food and Drug Administration. See Fisons plc v. Quigg, 1988 U.S. Dist. LEXIS 10935; 8 USPQ2d 1491, 1495 (D.D.C. 1988); aff’d., 876 F.2d 99, 110; 10 USPQ2d 1869, 1870 (Fed. Cir. 1989).

A patent is considered to claim the product at least in those situations where the patent claims the active ingredient per se, generically or specifically, or claims a composition or formulation which contains the active ingredient(s) and reads on the composition or formulation approved for commercial marketing or use.

III. NO PREVIOUS EXTENSIONS (WITH LIMITED EXCEPTIONS)

37 CFR 1.720(b) explains that patent term extension pursuant to 35 U.S.C. 156 is available only if the term of the patent has never been previously extended, except for extensions issued pursuant to 37 CFR 1.701, 1.760, or 1.790. An extension issued pursuant to 37 CFR 1.701 is an extension of the patent due to administrative delay within the Office. Note that the term of a patent is “adjusted,” not extended, pursuant to 37 CFR 1.702-1.705. An extension issued pursuant to 37 CFR 1.760 is an interim extension under 35 U.S.C. 156(e)(2). An extension issued pursuant to 37 CFR 1.790 is an interim extension under 35 U.S.C. 156(d)(5).

IV. REGULATORY REVIEW PERIOD

37 CFR 1.720(d) restates the statutory requirement set forth in 35 U.S.C. 156(a)(4). The regulatory review period must have been a regulatory review period defined by the statute. A regulatory review period under section 510(k) of the Federal Food, Drug and Cosmetic Act is not a regulatory review period which gives rise to eligibility for patent term extension under 35 U.S.C. 156. In re Nitinol Medical Technologies Inc., 17 USPQ2d 1492, 1492-1493 (Comm’r Pat. & Tm. 1990). See also Baxter Diagnostics v. AVL Scientific Corp., 798 F. Supp. 612, 619-620; 25 USPQ2d 1428, 1434 (C.D. Cal. 1992)(Congress intended only Class III medical devices to be eligible for patent term extension).

If the product is alleged to be a medical device, then regulatory review must have occurred under section 515, and not section 505, of the Federal Food, Drug and Cosmetic Act. Devices reviewed under the Humanitarian Device Exemption are considered to be reviewed under section 515. Drug products are not reviewed under section 515.

If more than one application for patent term extension is filed based upon a single regulatory review period, election will be required of a single patent. See MPEP § 2761.

V. FIRST PERMITTED MARKETING OR USE

37 CFR 1.720(e) follows 35 U.S.C. 156(a)(5), and sets forth that the approval under the relevant provision of law must have been the first permitted marketing or use of the product under the provision of law, unless the product is for use in food producing animals as explained below. See In re Patent Term Extension Application, U.S. Patent No. 3,849,549, 226 USPQ 283, 284 (Pat. & Tm. Office 1985). If the product is a human drug product, then the approval of the active ingredient must be the first permitted commercial marketing or use of the active ingredient as a single entity or in combination with another active ingredient under the provision of law under which regulatory review occurred.

Where a product contains multiple active ingredients, if any one active ingredient has not been previously approved, it can form the basis of an extension of patent term provided the patent claims that ingredient. See In re Alcon Laboratories Inc., 13 USPQ2d 1115, 1121 (Comm’r Pat. & Tm. 1989) for examples of products having different combinations of active ingredients. A different ratio of hormones is not a different active ingredient for purposes of 35 U.S.C. 156. Furthermore, an approved product having two active ingredients will not be considered to have a single active ingredient made of the two active ingredients. See Arnold Partnership v. Dudas, 362 F.3d 1338, 70 USPQ2d 1311 (Fed. Cir. 2004). A combination of two previously approved active ingredients does not comply with the first permitted commercial marketing or use requirement of 35 U.S.C. 156(a)(5) where the combination is alleged to be a single active ingredient because the two active ingredients display a pharmacological interaction. See Avanir Pharm. v. Kappos, No. 1:12cv69 (E.D. Va. March 21, 2012), transcript from Motions Hearing in U.S. Patent No. 5,206,248 (dated March 21, 2012). In considering whether a patent claiming an enantiomer, where the enantiomer was subject to pre-market regulatory review, is barred from receiving patent term extension in light of the previous approval of the racemate of the drug product, the court indicated that an enantiomer was a separate drug product from the racemate and each approved product could be the basis for extension of a patent that claims the product. See Ortho-McNeil Pharmaceutical Inc. v. Lupin Pharmaceuticals Inc., 603 F.3d 1377, 95 USPQ2d 1246 (Fed. Cir. 2010).

As to 35 U.S.C. 156(a)(5)(C), which is addressed in 37 CFR 1.720(e)(3), the term of a patent directed to a new animal drug or veterinary biological product may be extended based on a second or subsequent approval of the active ingredient provided all the following conditions exist:

• (A) the patent claims the drug or product;
• (B) the drug or product is not covered by the claims in any other patent that has been extended;
• (C) the patent term was not extended on the basis of the regulatory review period for use in non-food producing animals; and
• (D) the second or subsequent approval was the first permitted commercial marketing or use of the drug or product for administration to a food-producing animal. In this case, the application must be filed within sixty days of the first approval for administration to a food-producing animal.

For animal drugs or products, prior approval for use in a non-food producing animal will not make a patent ineligible for patent term extension based upon a later approval of the drug or product for use in food producing animals, if the later approval is the first approval of the drug or product for use in food producing animals.

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