PTAB

IPR2016-01111

Dr. Reddy's Laboratories, Inc. v. MonoSol Rx, LLC

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1. Case Identification

2. Patent Overview

  • Title: Uniform Films for Rapid Dissolve Dosage Form Incorporating Taste-Masking Compositions
  • Brief Description: The ’514 patent is directed to rapidly dissolving, thin-film drug delivery compositions for oral administration. The invention focuses on the manufacture of uniform pharmaceutical film products that incorporate taste-masked active components, ensuring consistent dosage in each film unit.

3. Grounds for Unpatentability

Ground 1: Claims 1-3, 9, 15, 62-65, 69-73, and 75 are obvious over Bess in view of Chen.

  • Prior Art Relied Upon: Bess (Patent 7,067,116) and Chen (WO 00/42992).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner asserted that the combination of Bess and Chen taught all elements of the challenged claims. Bess disclosed an orally dissolving film comprising a water-soluble polymer, a taste-masking agent, and a pharmaceutically active ingredient, with particulate sizes between 55 and 150 micrometers. Chen taught cast films using similar components (e.g., hydroxypropylmethylcellulose), methods for achieving uniformity by controlling viscosity (500-15,000 cps) and degassing the matrix, and the use of small particles to avoid a gritty mouth feel. Petitioner argued the key limitation—a drug content variation of less than 10%—was rendered obvious because both references taught methods to create uniform films. Bess disclosed a weight variance of approximately 4% (70 ± 3 mg), and Chen provided data showing low weight and thickness variation, which Petitioner contended would lead to the claimed drug uniformity.
    • Motivation to Combine: A person of ordinary skill in the art (POSITA) would combine Bess and Chen, as both address the common field of oral film drug delivery. The motivation would be to incorporate Chen's advanced techniques for achieving homogeneity and stability (e.g., specific viscosity ranges, degassing) into Bess's film formulation to create a product with improved, predictable dosage uniformity, as mandated by regulatory requirements and patient safety concerns.
    • Expectation of Success: A POSITA would have had a reasonable expectation of success. Both references use conventional film casting techniques and components, and Chen explicitly teaches methods to ensure a "uniform" and "homogenous" formulation. Applying Chen's process controls to Bess's composition would predictably result in a film with the claimed low dosage variability.
    • Key Aspects: Petitioner heavily relied on arguments that the PTAB, in prior reexaminations of related patents, had already found that Chen disclosed films with "substantially uniform" active content, arguing for the application of collateral estoppel on this issue.

Ground 2: Claims 1-3, 9, 15, 62-65, 69-73, and 75 are obvious over Chen in view of Cremer.

  • Prior Art Relied Upon: Chen (WO 00/42992) and Cremer (CA 2,274,910).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground presented an alternative combination where Chen was the primary reference, teaching the core composition and methods for achieving uniformity as detailed in Ground 1. Cremer was introduced for its disclosure of a flat, water-soluble drug delivery film containing buprenorphine. Crucially, Cremer taught that due to "homogenous thickness, density and width," its films exhibit a "direct relation" between a unit of length and the dose of active substance contained therein. Petitioner argued this teaching explicitly linked physical uniformity to dose uniformity, reinforcing Chen's teachings.
    • Motivation to Combine: A POSITA would combine Chen and Cremer to leverage the strengths of both disclosures. A formulator would be motivated to apply Chen's specific techniques for creating a stable, homogenous matrix to the film structure described by Cremer, which already recognized the principle of achieving dose uniformity through physical homogeneity. This combination would be a straightforward path to developing a reliable, uniform dosage form.
    • Expectation of Success: Success would be reasonably expected because the references describe compatible technologies. Cremer's principle of dose uniformity through physical consistency aligns perfectly with Chen's practical methods for achieving that physical consistency (e.g., viscosity control, controlled drying), making the outcome of the combination predictable.

4. Key Claim Construction Positions

  • "dried without the loss of substantial uniformity" (claims 1 and 62): Petitioner argued this term should be construed broadly as "any method of drying." This position was based on the Patent Owner's expert testimony in a co-pending litigation, where the expert allegedly admitted the claims were not limited to any particular form or parameters of drying. Petitioner asserted this construction was appropriate under the broadest reasonable interpretation standard and would prevent Patent Owner from narrowly interpreting the claims to exclude conventional drying methods taught by the prior art.

5. Key Technical Contentions (Beyond Claim Construction)

  • Inherent Uniformity in Prior Art Processes: A central technical contention was that the claimed drug content uniformity (less than 10% variance) was an inherent or at least obvious result of practicing the methods described in the prior art. Petitioner argued that Chen’s process—which involves creating a homogenous and uniform suspension, using specific viscosity ranges to prevent settling, degassing the mixture, and employing controlled drying—would necessarily produce films meeting the claimed uniformity limitation. This argument was intended to overcome the Patent Owner's position during prosecution that the prior art did not explicitly teach or suggest this level of uniformity.

6. Relief Requested

  • Petitioner requests institution of an inter partes review (IPR) and cancellation of claims 1-3, 9, 15, 62-65, 69-73, and 75 of the ’514 patent as unpatentable.