Prior art

The USPTO Patent Public Search tool can be used to search for patents. Patent number 11261151 is titled "Methods for making and using endoxifen". It was granted on March 1, 2022, and is directed to compositions of storage-stable Endoxifen and methods of treating hormone-dependent breast disorders using this Endoxifen. The estimated expiration for this patent is 2038.

To identify the most relevant prior art for US patent 11261151, I will examine the patent's cited references. US patent 11261151 itself references several U.S. patents related to tamoxifen's active metabolites, afimoxifene and endoxifen.

Here's a breakdown of relevant prior art cited within US patent 11261151:

U.S. Patents related to Afimoxifene (4-hydroxytamoxifen):

• U.S. Pat. No. 7,485,623:

  • Full Citation: U.S. Pat. No. 7,485,623, "Methods for treating breast disorders with 4-hydroxytamoxifen."
  • Publication/Filing Date: Granted February 3, 2009 (Filing date not explicitly stated in snippet, but the grant date is provided).
  • Brief Description: This patent describes methods for treating breast disorders using 4-hydroxytamoxifen (afimoxifene).
  • Potential Anticipated Claims: Claims related to methods of treating hormone-dependent breast disorders using endoxifen (a metabolite of tamoxifen, similar to afimoxifene) could potentially be anticipated, especially those in US11261151 that broadly cover treatment methods. For example, claims 26-30 of US11261151, which discuss methods of treating hormone-dependent breast disorders, might be relevant.

• U.S. Pat. No. 7,507,769:

  • Full Citation: U.S. Pat. No. 7,507,769, "Methods for treating breast disorders with 4-hydroxytamoxifen."
  • Publication/Filing Date: Granted March 24, 2009.
  • Brief Description: Similar to '623, this patent also describes methods for treating breast disorders with 4-hydroxytamoxifen.
  • Potential Anticipated Claims: Similar to the '623 patent, claims in US11261151 related to methods of treating hormone-dependent breast disorders (e.g., claims 26-30) could be implicated.

• U.S. Pat. No. 7,704,516:

  • Full Citation: U.S. Pat. No. 7,704,516, "Methods for treating breast disorders with 4-hydroxytamoxifen."
  • Publication/Filing Date: Granted April 27, 2010.
  • Brief Description: This patent further details methods for treating breast disorders using 4-hydroxytamoxifen.
  • Potential Anticipated Claims: Claims in US11261151 concerning treatment methods for hormone-dependent breast disorders (e.g., claims 26-30).

• U.S. Pat. No. 7,786,172:

  • Full Citation: U.S. Pat. No. 7,786,172, "Compositions and methods for treating breast disorders with 4-hydroxytamoxifen."
  • Publication/Filing Date: Granted August 31, 2010.
  • Brief Description: This patent covers both compositions and methods for treating breast disorders with 4-hydroxytamoxifen.
  • Potential Anticipated Claims: Claims related to both compositions comprising endoxifen (e.g., claims 1-25) and methods of treating breast disorders (e.g., claims 26-30) in US11261151.

• U.S. Pat. No. 7,968,532:

  • Full Citation: U.S. Pat. No. 7,968,532, "Compositions and methods for treating breast disorders with 4-hydroxytamoxifen."
  • Publication/Filing Date: Granted June 28, 2011.
  • Brief Description: This patent also describes compositions and methods for treating breast disorders with 4-hydroxytamoxifen.
  • Potential Anticipated Claims: Similar to the '172 patent, claims in US11261151 covering compositions of endoxifen and methods of treating breast disorders (e.g., claims 1-30).

• U.S. Pat. No. 8,048,927:

  • Full Citation: U.S. Pat. No. 8,048,927, "Compositions and methods for treating breast disorders with 4-hydroxytamoxifen."
  • Publication/Filing Date: Granted November 1, 2011.
  • Brief Description: This patent is another in the series covering compositions and methods for treating breast disorders with 4-hydroxytamoxifen.
  • Potential Anticipated Claims: Claims in US11261151 related to endoxifen compositions and methods of treating breast disorders (e.g., claims 1-30).

U.S. Patents related to Endoxifen:

• U.S. Pat. No. 9,333,190:

  • Full Citation: U.S. Pat. No. 9,333,190, "Endoxifen citrate and methods of use thereof."
  • Publication/Filing Date: Granted May 10, 2016.
  • Brief Description: This patent specifically mentions endoxifen citrate and its methods of use.
  • Potential Anticipated Claims: Claims in US11261151 that relate to endoxifen salts (specifically citrate, though 11261151 focuses on gluconate and other salts), pharmaceutical compositions containing endoxifen, and methods of using endoxifen for treatment (e.g., claims 1-30). US11261151 claims to provide novel industrially scalable methods of making Z-endoxifen or salts thereof, crystalline forms of endoxifen, and compositions comprising them, which could be differentiated from existing endoxifen formulations. The '190 patent mentions citrate salts of endoxifen, while US11261151 introduces other salts and crystalline forms.

• U.S. Pat. No. 9,220,680:

  • Full Citation: U.S. Pat. No. 9,220,680, "Methods of treating cancer."
  • Publication/Filing Date: Granted December 29, 2015.
  • Brief Description: This patent is broadly directed to methods of treating cancer, and endoxifen is mentioned as an active metabolite of tamoxifen in the context of efficacy and resistance.
  • Potential Anticipated Claims: Claims in US11261151 pertaining to methods of treating hormone-dependent breast disorder or reproductive tract disorder, as these are types of cancer or pre-cancerous conditions (e.g., claims 26-30). Given the broad nature of the '680 patent, the novelty of US11261151 would likely rest on the specific compositions, crystalline forms, and pharmacokinetic profiles described, rather than the general concept of using endoxifen for cancer treatment.

It is important to note that US11261151 itself states that prior art in connection with tamoxifen therapy indicates severe side effects and patient compliance issues, as well as reduced efficacy and increased resistance due to cytochrome P450 (CYP) mutations affecting tamoxifen's conversion to endoxifen. This patent addresses these issues by providing novel industrially scalable methods of making Z-endoxifen or its salts, crystalline forms, and compositions, aiming for improved bioavailability and stability. Therefore, while the cited prior art establishes the general knowledge of tamoxifen metabolites and their use in treating breast disorders, US11261151 seeks to distinguish itself through specific manufacturing processes, crystalline forms, and resulting pharmacokinetic profiles for endoxifen.