Amgen Inc v. Teva Pharma USA Inc

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Amgen Inc. (Delaware)
  • Defendant: Teva Pharmaceuticals USA, Inc. (Delaware) and Teva Pharmaceutical Industries Ltd. (Israel)
  • Plaintiff’s Counsel: Morris, Nichols, Arsht & Tunnell LLP
• Case Identification: 1:17-cv-01809, D. Del., 12/15/2017
• Venue Allegations: Venue is alleged to be proper because Defendant Teva USA is a Delaware corporation that conducts business in the state, and Defendant Teva Ltd. has allegedly directed actions toward Delaware and purposefully availed itself of the rights and benefits of Delaware law.
• Core Dispute: Plaintiff alleges that Defendants’ filing of an Abbreviated New Drug Application (ANDA) for a generic version of Plaintiff's SENSIPAR® product constitutes an act of infringement of a patent related to a rapid dissolution pharmaceutical formulation.
• Technical Context: The technology concerns pharmaceutical formulations designed to improve the dissolution rate and bioavailability of poorly water-soluble drug compounds, specifically for treating conditions associated with hyperparathyroidism.
• Key Procedural History: This action arises under the Hatch-Waxman Act following Defendants' submission of an ANDA to the FDA. The complaint notes a history of prior litigation between the parties concerning "Earlier Listed Patents" for the same drug, SENSIPAR®. Plaintiff listed the patent-in-suit in the FDA's Orange Book, and Defendants allegedly have tentative FDA approval for their generic product, with an intended launch date after the expiration of one of the earlier patents.

Case Timeline

Date	Event
2003-09-12	’405 Patent Priority Date
2004-03-08	FDA approval for Amgen's SENSIPAR®
2008-06-12	Amgen receives notice of Teva's ANDA filing for SENSIPAR®
2010-04-23	Teva receives tentative FDA approval for its ANDA product
2016-06-28	U.S. Patent No. 9,375,405 Issues
2016-07-22	Approximate date '405 Patent listed in FDA Orange Book
2017-12-15	Complaint Filed
2018-03-08	Earliest anticipated launch date for Defendants' ANDA product

II. Technology and Patent(s)-in-Suit Analysis

U.S. Patent No. 9,375,405 - "Rapid Dissolution Formulation of a Calcium Receptor-Active Compound"

• Issued: June 28, 2016

The Invention Explained

• Problem Addressed: The patent’s background section states that certain calcium receptor-active compounds, such as cinacalcet HCl, can be "insoluble or sparingly soluble in water," particularly at neutral pH ('405 Patent, col. 1:11-14). This limited solubility can reduce the number of available formulation options and potentially result in low or inconsistent bioavailability of the drug when administered orally ('405 Patent, col. 1:19-23).
• The Patented Solution: The invention claims to solve this problem through a specific pharmaceutical composition with a "defined dissolution profile" ('405 Patent, col. 2:30-32). The composition combines the active ingredient, cinacalcet HCl, with a particular combination of excipients—including a diluent, a binder, and a disintegrant—within specified weight percentage ranges to maximize the dissolution of the compound from the dosage form ('405 Patent, col. 1:24-28; col. 13:17-39). The patent describes a manufacturing process involving granulation to achieve the desired properties (see generally ’405 Patent, FIG. 1).
• Technical Importance: This formulation technology provides a method for creating a stable, oral solid dosage form of cinacalcet with rapid and predictable drug release characteristics, which is important for ensuring consistent therapeutic effects in patients being treated for conditions like secondary hyperparathyroidism ('405 Patent, col. 4:16-21).

Key Claims at a Glance

• The complaint asserts at least independent claim 1 (Compl. ¶42).
• Independent Claim 1 requires a pharmaceutical composition comprising:
  • (a) from about 10% to about 40% by weight of cinacalcet HCl in an amount from about 20 mg to about 100 mg;
  • (b) from about 45% to about 85% by weight of a diluent selected from a specified group (microcrystalline cellulose, starch, etc.);
  • (c) from about 1% to about 5% by weight of a binder selected from a specified group (povidone, etc.);
  • (d) from about 1% to 10% by weight of a disintegrant selected from a specified group (crospovidone, etc.);
  • wherein the composition is for the treatment of hyperparathyroidism, hyperphosphonia, hypercalcemia, or elevated calcium phosphorus product.
• The complaint does not explicitly reserve the right to assert dependent claims.

III. The Accused Instrumentality

Product Identification

• The accused instrumentalities are Defendants’ generic "cinacalcet hydrochloride tablets (EQ 90 mg base)" for which Defendants filed Abbreviated New Drug Application ("ANDA") No. 090539 with the FDA (Compl. ¶6).

Functionality and Market Context

• The complaint alleges that Defendants' ANDA products are generic versions of Amgen’s SENSIPAR® tablets (Compl. ¶26). These products are intended for the same therapeutic uses, such as treating secondary hyperparathyroidism in patients with chronic kidney disease and hypercalcemia in patients with parathyroid carcinoma (Compl. ¶18-20).
• The complaint alleges that Defendants seek FDA approval to market their ANDA products prior to the expiration of the ’405 Patent and have received tentative approval from the FDA (Compl. ¶6, ¶29). The act of filing the ANDA to obtain approval for a generic drug is the statutory act of infringement alleged in the complaint (Compl. ¶41).

IV. Analysis of Infringement Allegations

The complaint does not provide a claim chart or specific details regarding the formulation of Defendants' ANDA products, as this information is confidential and typically obtained during discovery. The infringement allegations are therefore based on information and belief. No probative visual evidence provided in complaint.

The core infringement theory is that by filing an ANDA for a generic equivalent of SENSIPAR®, Defendants are seeking approval to manufacture and sell a product that necessarily falls within the scope of the asserted claims of the ’405 Patent (Compl. ¶42). The complaint alleges that Defendants' ANDA products will infringe "either literally or under the doctrine of equivalents" (Compl. ¶42). The success of this allegation will depend on the precise formulation disclosed in Defendants' confidential ANDA submission.

Identified Points of Contention

• Technical Questions: A primary factual question for the court will be whether the formulation detailed in Defendants' confidential ANDA No. 090539 meets the specific compositional limitations of claim 1. This includes determining if the weight percentages of cinacalcet HCl, the diluent, the binder, and the disintegrant fall within the claimed ranges.
• Scope Questions: Claim 1 includes a "wherein the composition is for the treatment of..." clause. A potential point of dispute may be whether this use limitation is met. The contents of the proposed product label submitted with Defendants' ANDA will be key evidence for this element.

V. Key Claim Terms for Construction

The Term

• "about"

Context and Importance

• This term modifies all the numerical weight percentage ranges in independent claim 1 (e.g., "from about 10% to about 40%"). The construction of "about" is critical because it defines the boundaries of the claimed formulation. If Defendants' formulation uses a percentage just outside a recited range, the definition of "about" could be dispositive of literal infringement.

Intrinsic Evidence for Interpretation

• Evidence for a Broader Interpretation: The patent specification uses the term "about" frequently when discussing component amounts and processing parameters, which may suggest the inventors did not intend for the recited ranges to be interpreted with strict, absolute precision ('405 Patent, col. 4:9-14, col. 9:8-14). Parties may argue that "about" should be interpreted in light of the overall goal of achieving a specific dissolution profile, allowing for some reasonable variation from the stated numbers.
• Evidence for a Narrower Interpretation: The patent provides detailed examples with specific weight percentages for each component, such as 18.367% for cinacalcet HCl in one formulation ('405 Patent, Table at col. 11:15-18). A party could argue these examples anchor the term "about" to a narrow range, covering only minor variations attributable to standard manufacturing or measurement tolerances, and not extending to formulations that are materially different from those explicitly disclosed.

VI. Other Allegations

Indirect Infringement

• The complaint alleges that once the ANDA is approved, Defendants' manufacture, use, and sale of the generic product will induce and/or contribute to the infringement of claim 1 ('405 Patent, Compl. ¶48). The basis for this allegation is that Defendants will market the product with a label instructing physicians and patients to use it for the patented methods of treatment, thereby encouraging direct infringement by end-users (Compl. ¶6, ¶18-20).

Willful Infringement

• The complaint does not use the word "willful" but does request a declaration that the case is "exceptional" under 35 U.S.C. § 285, which allows for the award of attorney fees (Compl., Prayer for Relief ¶D). The complaint alleges facts that may support a finding of willfulness, stating that Defendants have been aware of the ’405 Patent since at least its listing in the Orange Book around July 22, 2016, and had notice via related litigation as of March 30, 2017 (Compl. ¶33-36). The complaint further alleges that Defendants' continued pursuit of their ANDA after the patent was listed in the Orange Book indicates a "refusal to change their course of action" (Compl. ¶47).

VII. Analyst’s Conclusion: Key Questions for the Case

• A central evidentiary question will be one of compositional identity: does the precise formulation disclosed in Defendants' confidential ANDA submission contain the same components in the same weight-percentage ranges as those recited in claim 1 of the ’405 patent? The case will turn heavily on discovery of the ANDA's contents.
• A key legal issue will be one of definitional scope: how broadly will the court construe the term "about"? The outcome will determine the literal boundaries of the claimed percentage ranges and could be dispositive if Defendants' formulation lies close to, but not squarely within, those ranges.
• A third core issue will relate to the method-of-use limitation: does the proposed product labeling in Defendants' ANDA direct use of the generic product for treating one of the specific conditions (e.g., hyperparathyroidism) recited in claim 1, thereby satisfying that element of the claim?