Prior art — US Patent 12403095

Analysis of Prior Art for U.S. Patent 12,403,095

An evaluation of the prior art cited in U.S. Patent 12,403,095 has been performed to determine its relevance to the patent's claims under 35 U.S.C. § 102. The following references are considered the most pertinent.

U.S. Patent Application Publication No. 2008/0132533 A1 (Yeom et al.)

Full Citation: US 2008/0132533 A1
Publication Date: June 5, 2008
Filing Date: November 29, 2007
Brief Description: Yeom discloses a solid dispersion formulation of tacrolimus with an enteric polymer to enhance stability by reducing recrystallization, particularly under high temperature and humidity. The formulation is designed to release tacrolimus quickly in aqueous media to improve bioavailability.
Potential Anticipation of Claims:
- Claims 1 and 11: Yeom teaches the use of a solid dispersion of tacrolimus to improve stability, which is a core concept of the '095 patent. Specifically, it mentions conducting stability tests at 40°C and 75% relative humidity, directly relevant to the conditions specified in claim 1. However, Yeom's focus is on using enteric polymers to prevent recrystallization rather than a metal-chelating stabilizing agent to prevent chemical degradation (specifically the formation of 8-epitacrolimus) by controlling pH. Yeom does not appear to disclose a stabilizing agent that is a metal chelator or one that provides a pH below 7. Furthermore, it does not specify limitations on the formation of 8-epitacrolimus.

U.S. Patent No. 7,994,214 B2 (Holm et al.)

Full Citation: US 7,994,214 B2
Publication Date: August 9, 2011
Filing Date: July 7, 2009
Brief Description: This patent, which shares an inventor with the '095 patent, describes solid dispersions of tacrolimus in a hydrophilic or water-miscible vehicle. The concentration of tacrolimus is specified to be between approximately 0.01% and 15% w/w. The invention aims to prepare solid oral dosage forms like tablets and capsules.
Potential Anticipation of Claims:
- Claims 1 and 11: Holm '214 discloses a solid dispersion of tacrolimus in a vehicle at concentrations that overlap with the ranges claimed in the '095 patent. It also mentions that stabilizing agents may be added to ensure the stability of the solid dispersion. However, it does not specifically require a metal-chelating agent that provides a pH below 7, nor does it set forth the specific stability requirements concerning the limited formation of 8-epitacrolimus under the precise conditions laid out in claims 1 and 11 of the '095 patent.

U.S. Patent Application Publication No. 2006/0177500 A1 (Shin et al.)

Full Citation: US 2006/0177500 A1
Publication Date: August 10, 2006
Filing Date: August 26, 2005
Brief Description: Shin discloses a solid dispersion of tacrolimus prepared by dissolving tacrolimus and a solid carrier in an organic solvent and then drying the mixture. The solid carriers mentioned include sucrose fatty acid esters and sodium lauryl sulfate. The goal is to increase the dissolution rate of tacrolimus.
Potential Anticipation of Claims:
- Claims 1 and 11: While Shin teaches a solid dispersion of tacrolimus, it relies on a solvent-based method for preparation. The '095 patent focuses on a melt-based dispersion. More importantly, Shin does not mention the use of a stabilizing agent that is a metal chelator, the control of pH to below 7, or the specific stability limitations regarding 8-epitacrolimus formation. The carriers disclosed are for improving dissolution and are not described as having stabilizing or pH-modifying properties.

European Patent No. 2575769 B1 (Veloxis Pharmaceuticals A/S)

Full Citation: EP 2575769 B1
Publication Date: April 3, 2013
Filing Date: February 17, 2011
Brief Description: This European patent, from the same assignee as the '095 patent, is highly relevant as it explicitly discloses stabilized pharmaceutical compositions of tacrolimus. It describes a solid dispersion of tacrolimus with a stabilizing agent to prevent the formation of degradation products, including 8-epitacrolimus. It mentions using organic acids like tartaric acid as stabilizing agents and provides examples of compositions with PEG 6000 and poloxamer 188 as the vehicle. It also discloses stability data after storage at 25°C/60% RH.
Potential Anticipation of Claims:
- Claims 1 and 11: This reference appears to be the most relevant prior art. It discloses many key elements of the '095 patent's claims, including a solid dispersion of tacrolimus, the use of a stabilizing agent to reduce the formation of 8-epitacrolimus, and stability testing under conditions similar to those in claim 11. The disclosure of tartaric acid (a known metal chelator and acid) and a vehicle of PEG and poloxamer is also significant. A detailed analysis would be required to determine if this European patent discloses all the limitations of the independent claims of the '095 patent, particularly the precise percentage increase limits for 8-epitacrolimus under the specified storage conditions and the explicit limitation that tacrolimus is the sole active ingredient. It is highly likely that this reference would be a key piece of prior art in any validity challenge.