Prior art

To identify the most relevant prior art for US patent 12447128, I will examine the patent's cited references. Based on the patent text provided, the following prior art documents are explicitly mentioned:

• U.S. Pat. No. 7,709,517 (US7709517B2): This patent is cited multiple times in US12447128B2. It discloses diarylhydantoin compounds, including diarylthiohydantoins, and methods for synthesizing and using them to treat hormone-refractory prostate cancer. Enzalutamide's chemical name and structural formula are mentioned in relation to this patent. US7709517B2 also discusses pharmaceutical compositions comprising a therapeutically effective amount of such compounds and a pharmaceutically acceptable carrier, along with methods for treating hyperproliferative disorders like hormone-refractory prostate cancer. The US12447128B2 patent states that enzalutamide is provided commercially as a soft capsule (XTANDI®) and that US7709517B2 discloses the use of enzalutamide as an agent for treating castration-resistant prostate cancer.

  • Publication/Filing Date: The priority date for US7709517B2 is May 13, 2005, and it was granted on May 4, 2010.
  • Brief Description: This patent introduces diarylhydantoin compounds (including diarylthiohydantoins like enzalutamide) as androgen receptor antagonists, their synthesis, and their use in treating hormone-refractory prostate cancer. It also covers pharmaceutical compositions containing these compounds.
  • Potential Anticipation (35 U.S.C. § 102): US7709517B2 potentially anticipates claims in US12447128B2 related to the compound enzalutamide itself, its chemical structure, its use in treating prostate cancer, and basic pharmaceutical compositions (e.g., comprising enzalutamide and a pharmaceutically acceptable carrier), as it is the foundational patent disclosing enzalutamide. However, US12447128B2 focuses on formulations of enzalutamide, specifically amorphous forms and solid dispersions, which are not explicitly detailed in US7709517B2 as its primary focus. For instance, US12447128B2 notes that enzalutamide in US7709517B2 exists as a colorless crystal, contrasting with the amorphous forms claimed in 12447128.

• US2002/0031547: This patent literature reports a sparingly soluble compound held on a gel-forming water-soluble polymer as a solid dispersion, where a salt substance is included to improve disintegration time and dissolution profile.

  • Publication/Filing Date: While the exact filing date isn't immediately available from the provided text, the publication date is listed as 2002/0031547.
  • Brief Description: Discloses solid dispersions of sparingly soluble compounds with gel-forming water-soluble polymers, incorporating salt substances for improved disintegration and dissolution.
  • Potential Anticipation (35 U.S.C. § 102): This patent potentially anticipates claims related to general concepts of solid dispersions for sparingly soluble compounds, the use of gel-forming water-soluble polymers (like HPMC or HPC mentioned in the context of this reference in US12447128B2's background), and enhancing dissolution properties. However, it does not specifically mention enzalutamide.

• US2002/0009494: This publication reports the use of hydroxypropylmethylcellulose acetate succinate (HPMCAS) in a pharmaceutical composition of a sparingly soluble compound, prepared by a spray drying method, to improve aqueous solubility and/or bioavailability.

  • Publication/Filing Date: The publication date is January 26, 2001.
  • Brief Description: Focuses on using HPMCAS in spray-dried solid amorphous dispersions of sparingly soluble drugs to enhance aqueous solubility and bioavailability. It also mentions that such dispersions can be prepared by forming a homogeneous solution or melt of the drug and matrix material followed by solidifying the mixture by cooling or solvent removal.
  • Potential Anticipation (35 U.S.C. § 102): This patent is highly relevant as it describes amorphous solid dispersions of sparingly soluble drugs using a specific polymer (HPMCAS) and a specific method of preparation (spray drying) to improve bioavailability, directly aligning with key aspects of US12447128B2. It could potentially anticipate claims in US12447128B2 related to the general concept of amorphous solid dispersions of poorly soluble drugs with HPMCAS, prepared via spray-drying for improved solubility and bioavailability. Claims related to compositions comprising amorphous enzalutamide and HPMCAS, and methods of making them via spray-drying, would need to demonstrate novelty over the general teachings of this reference.

• U.S. Pat. No. 7,611,630 B2: This patent is referenced for further details on the membrane permeation test.

  • Publication/Filing Date: The provided text does not explicitly state the publication or filing date for US7611630B2, only its reference.
  • Brief Description: Provides details on a "membrane permeability test" used to assess the capacity of a dispersion to resupply free drug in solution.
  • Potential Anticipation (35 U.S.C. § 102): This patent describes an analytical method and would not anticipate compositional or method claims of US12447128B2. It is cited as a methodology reference.

In summary, US7709517B2 establishes the active pharmaceutical ingredient (enzalutamide) and its therapeutic use. US2002/0031547 and US2002/0009494 are particularly pertinent as they deal with the broader concepts of solid dispersions and methods for improving drug solubility and bioavailability, which are central to the claims of US12447128B2. US2002/0009494, specifically mentioning HPMCAS and spray-drying for sparingly soluble compounds, appears to be the most relevant in terms of potentially anticipating the formulation aspects of US12447128B2.