Amgen, KAI Pharmaceuticals Sue Aurobindo for Infringement of Patents Relating to Drug Parsabiv

Amgen Inc. and its subsidiary KAI Pharmaceuticals Inc. filed a complaint in the District of Delaware last week against Aurobindo Pharma Limited and Aurobindo Pharma USA Inc. (collectively, Aurobindo), alleging that Aurobindo infringed their patents by filing for a generic version of the drug Parsabiv.

According to the complaint, Aurobindo filed Abbreviated New Drug Application (ANDA) No. 215840 to the U.S. Food and Drug Administration (FDA) “seeking approval to manufacture and sell a generic version of Parsabiv® (etelcalcetide) injection for intravenous use at strengths of 2.5mg/0.5mL, 5mg/mL, and 10mg/2mL (‘Aurobindo’s Proposed ANDA Product’)” before the plaintiffs’ patents – U.S. Patent Nos. 9,820,938 and 10,344,765 – expire. The plaintiffs stated that they were notified by Aurobindo in a letter that they received in March 2021 that it submitted the ANDA. The plaintiffs alleged that based on information and belief, Aurobindo’s Proposed ANDA Product will be marketed as a competing drug to Parsabiv, which Amgen and KAI purportedly developed “for the treatment of secondary hyperparathyroidism in adults with chronic kidney disease on hemodialysis.”

For background, the plaintiffs claimed that the FDA approved Parsabiv on February 7, 2017, for the marketing, sale, and patient treatment of the drug with New Drug Application (NDA) No. 20835 in the FDA’s Orange Book. The plaintiffs averred that the active ingredient in Parsabiv is etelcalcetide, “a synthetic peptide calcium-sensing receptor agonist.” The plaintiffs noted that Parsabiv is approved by the FDA for intravenous injection as a “sterile, preservative-free, ready-to-use clear and colorless solution in a single-dose vial containing 5 mg/mL of etelcalcetide. Each vial contains 2.5, 5, or 10 mg etelcalcetide. Each vial is formulated with 0.85% weight/volume sodium chloride, 10mM succinic acid, and adjusted to pH 3.3 with sodium hydroxide and/or hydrochloric acid.”

Amgen and KAI proffered that in Aurobindo’s notice letter it claimed that the plaintiffs’ patents-in-suit are “invalid, unenforceable, and/or will not be infringed by the commercial manufacture, use, sale, or offer for sale of Aurobindo’s Proposed ANDA Product.” However, the plaintiffs noted that in Aurobindo’s letter it stated it was not seeking FDA approval “to engage in the commercial manufacture, use, sale, offer for sale, and/or importation of Aurobindo’s Proposed ANDA Product” before the expiration of the plaintiffs’ other patents relating to Parsabiv. Amgen and KAI averred that they believe that etelcalcetide is the active ingredient in Aurobindo’s Proposed ANDA Product and its formula will allegedly have a pH between 2.0 and 5.0, as is the plaintiffs’ drug Parsabiv. Moreover, the plaintiffs alleged that Aurobindo’s ANDA relies on the plaintiffs’ NDA for Parsabiv and “contains data that … demonstrate bioequivalence of Aurobindo’s Proposed ANDA Product and Parsabiv.”

Aurobindo is accused of infringing the plaintiffs’ asserted patents because of the purported similarity of the products, including pH level and the use of the ingredient etelcalcetide, before the expiration date of the asserted patents and the proposed use of the products and associated company conduct.

The plaintiffs seek declaratory judgment in their favor, an order providing the effective date of the FDA approval for Aurobindo to be after the expiration dates of the asserted patents; a permanent injunction, an award for costs and fees, and other relief.

Amgen and KAI are represented by Morris, Nichols, Arsht & Tunnell LLP and Latham & Watkins LLP.