Merck Sharp & Dohme B.V. v. Aurobindo Pharma USA, Inc., decided March 13, 2025

Case Name and Citation: MERCK SHARP & DOHME B.V. v. AUROBINDO PHARMA USA, INC., decided March 13, 2025 (United States Court of Appeals for the Federal Circuit, Appeal No. 2023-2254)

Court: United States Court of Appeals for the Federal Circuit

Date of Decision: March 13, 2025

Issue Presented: The central issue on appeal is whether the Patent Term Extension (PTE) for a reissued patent, under the Hatch-Waxman Act (35 U.S.C. § 156(c)), should be calculated based on the issue date of the original patent or the issue date of the reissued patent, particularly when the reissued patent retains claims directed to the drug product that were present in the original patent.

Holding: The Federal Circuit affirmed the district court's holding, concluding that in the context of reissued patents, "the patent" referred to in 35 U.S.C. § 156(c) is the original patent, especially when the reissued patent retains claims directed to the active ingredient of the approved drug. Therefore, the PTE for the reissued patent in this case was correctly calculated based on the issue date of the original patent.

Facts:

• Merck owned U.S. Patent No. 6,670,340 (the "'340 patent"), which issued on December 30, 2003, covering a class of 6-mercapto-cyclodextrin derivatives. Claim 4 was exemplary.

• On April 13, 2004, Merck applied to the FDA for approval of sugammadex, the active ingredient in BRIDION®, which falls within the scope of the '340 patent's claims.

• While FDA regulatory review was pending, Merck filed a reissue application for the '340 patent. The reissued patent, U.S. Patent No. RE44,733 (the "RE'733 patent"), issued on January 28, 2014, retaining all original claims and adding narrower claims specifically directed to sugammadex (e.g., Claim 21).

• Sugammadex received FDA approval on December 15, 2015.

• Merck applied for a five-year PTE for the RE'733 patent based on the '340 patent's original issue date. The PTO granted this PTE, extending the RE'733 patent's expiration date to January 27, 2026.

• Aurobindo and other generic drug manufacturers (Defendants-Appellants) filed Abbreviated New Drug Applications (ANDAs) seeking to market generic versions of BRIDION®, including Paragraph IV certifications asserting that the RE'733 patent was invalid or would not be infringed.

• Merck sued for infringement under 35 U.S.C. § 271(e)(2)(A).

• Aurobindo argued that the RE'733 patent was only entitled to a significantly shorter PTE calculated from the reissued patent's issue date, as only a portion of the regulatory review period occurred after that date. They contended that "the patent" in § 156(c) plainly refers to the patent for which extension is sought, i.e., the RE'733 patent.
  

Reasoning:

The Federal Circuit's decision hinged on the interpretation of the phrase "the patent" in 35 U.S.C. § 156(c), which states: "The term of a patent eligible for extension under subsection (a) shall be extended by the time equal to the regulatory review period for the approved product which period occurs after the date the patent is issued[.]"

• Ambiguity of the Statute: The court acknowledged that the language of § 156(c) alone is ambiguous as to whether "the patent" refers to the original or the reissued patent.

• Statutory Context and Purpose: The court emphasized that statutory language must be interpreted within its broader context and considering the purpose of the statute. Citing Caraco Pharm. Lab'ys, Ltd. v. Novo Nordisk A/S, the court noted the importance of understanding the statutory scheme as a whole.

• Purpose of the Hatch-Waxman Act: The court reiterated that the purpose of the Hatch-Waxman Act, particularly the PTE provision, is to compensate pharmaceutical companies for the reduction in their effective patent terms due to the time required for lengthy regulatory review by the FDA. The court quoted legislative history and prior Federal Circuit cases (Glaxo, Inc. v. Novopharm, Ltd., Merck & Co. v. Hi-Tech Pharmacal Co., Merck & Co. v. Kessler) to underscore this compensatory goal.

·       "We have recognized that the purpose of the Hatch-Waxman Act is to ‘provid[e] patent holders with limited extensions of patent term in order to recover a portion of the market exclusivity lost during the lengthy process of development and FDA review.’"

·       "In particular, ‘[t]he statute contemplates a patentee receiving time lost in its patent term by reason of FDA delay, and the statute should be liberally interpreted to achieve this end.’"

• Application to Reissued Patents: The court concluded that the Hatch-Waxman Act contemplates PTE for reissued patents that contain claims directed to drug products whose exclusivity was delayed by FDA review. Construing "the patent" as the original patent in this scenario aligns with the Act's purpose by compensating Merck for the exclusivity lost during regulatory delay.

• Rejection of Aurobindo's Argument: The court rejected Aurobindo's argument that the original patent is "dead" upon reissue and therefore cannot be "the patent" referred to in § 156(c). The court clarified that while the original patent ceases to exist as a separately enforceable right, the reissued patent inherits the unexpired term of the original patent under 35 U.S.C. § 251(a). Section 156 aims to extend the term that originated with the original patent.

·       "Section 156 is designed to extend the term of the original patent, not to make the original patent enforceable after reissue."

• Consistency with Other Statutory Provisions: The court found further support in other provisions of the Patent Act, particularly § 156(a), which refers to extending the term "from the original expiration date of the patent," and § 154(a)(2), which ties the patent term to the filing date of the original patent.

·       "Subsection 156(a) provides that ‘the term of a patent . . . shall be extended . . . from the original expiration date of the patent.’ 35 U.S.C § 156(a) (emphasis added). The most natural reading of this language is that ‘the patent’ must be the original patent, since the ‘original expiration date’ is tied to the filing date of the original patent, not the reissued patent."

• PTO Practice: The court noted that the PTO's revised Manual of Patent Examining Procedure (MPEP § 2766) supports its conclusion, stating that the original patent grant date should be used to calculate PTE for a reissued patent as long as both the original and reissued patents claimed the approved product.

·       "It has been revised to provide that ‘[w]ith respect to calculating the amount of extension to which the reissued patent is entitled to receive, so long as the original patent claimed the approved product and the reissued patent claims the approved product, the original patent grant date would be used to calculate the extension to which the reissued patent would be entitled.’"

• Distinction from Other Reissue Scenarios: The court acknowledged that "difficult questions arise in cases where the original patent did not include any claims directed to the drug product and was later reissued to include broader claims directed to such products." However, this scenario was not before the court as the '340 patent did include claims to the active ingredient.

  
  

Conclusion:

This decision provides important clarity on the calculation of PTE for reissued patents under the Hatch-Waxman Act. It confirms that when a reissued patent retains claims to a drug product that were present in the original patent, the PTE should be calculated based on the original patent's issue date. This interpretation upholds the compensatory purpose of the PTE provision by ensuring that patent holders are compensated for the regulatory delay they faced in bringing their patented drugs to market, even if they subsequently sought a reissue of the patent. The decision reinforces the principle that statutory interpretation should consider the overall statutory scheme and the intended purpose of the legislation.