US 11623920

Patent Analyst Report: US 11,623,920 B2

Date of Analysis: 2026-05-05

Subject: United States Patent 11,623,920 B2

This report provides a concise summary of US patent 11,623,920, including its key bibliographic data and a plain-language overview of its independent claims. A search of the United States Patent and Trademark Office (USPTO) database and the 2026 dockets of the Court of Appeals for the Federal Circuit (CAFC) was conducted. No records of litigation involving this patent were found in the CAFC dockets for the current year.

I. Bibliographic Information

II. Plain-Language Overview of Independent Claims

An independent claim represents the broadest definition of the invention protected by the patent. Infringement of an independent claim is sufficient for a finding of patent infringement. US Patent 11,623,920 has one independent claim.

Independent Claim 1:

This claim protects a new crystalline form of pitolisant hydrochloride, specifically referred to as pitolisant hydrochloride sesquihydrate. A "sesquihydrate" means that for every two molecules of pitolisant hydrochloride, there are three molecules of water integrated into the crystal structure.

The claim defines this specific crystalline form by its unique fingerprint when analyzed with Powder X-ray Diffraction (PXRD), a standard analytical technique. It specifies that this form is characterized by having prominent peaks at certain angles (5.3, 7.3, 10.0, 11.8, and 26.1 ±0.2° two-theta). This unique pattern distinguishes it from other known forms of pitolisant hydrochloride.

In essence, this claim grants the patent holder exclusive rights to this particular stable, hydrated crystal form of the active pharmaceutical ingredient pitolisant hydrochloride.

To the best of my knowledge as of May 5, 2026, there is no known litigation involving US patent 11,623,920.

A comprehensive search of publicly available litigation databases, including the Unified Patents Portal, the Public Access to Court Electronic Records (PACER) service, and the dockets of the Court of Appeals for the Federal Circuit (CAFC), was conducted. These searches yielded no records of any legal disputes, infringement suits, or any other form of litigation specifically naming US patent 11,623,920.

Proceedings overview

There are no AIA trial proceedings on file for US Patent 11,623,920. This indicates that all claims of the patent are currently untested by the PTAB, offering a clean slate for any potential defendant considering an AIA trial challenge.

Strategic summary

Currently, all claims of US Patent 11,623,920 remain untested by any AIA trial proceeding. No claims have been canceled or sustained through IPR, PGR, or CBM. The patent has not been narrowed through PTAB challenges.

Regarding the estoppel landscape, since no AIA trial proceedings have been instituted or reached a final written decision, there is no estoppel under § 315(e)(2) for any petitioner (or their privies). All prior-art grounds and statutory bases (§ 102, § 103, § 112) remain available for a potential challenger. There is no discernible pattern of activity by petitioners or the patent owner at the PTAB, as no proceedings exist.

Recommended next steps

As of 2026-05-31, there is no PTAB activity on file for US Patent 11,623,920. This absence of proceedings can be a signal that the patent has not yet been subjected to significant challenges, despite being issued on 2023-04-11. For a potential defendant, this means the opportunity exists to be the first to test the patent's validity at the PTAB, with all potential prior art and grounds available.

Inventors

• Ramasamy Venkatragavan (Nuray Chemicals Pvt Ltd)
• Erugu Balaiah (Nuray Chemicals Pvt Ltd)
• Paramanandam Senthilkumaran (Nuray Chemicals Pvt Ltd)
• Guttha Jayaprasad (Nuray Chemicals Pvt Ltd)
• Manniyam Kailasam Selvam (Nuray Chemicals Pvt Ltd)
• Noti Krishnareddy (Nuray Chemicals Pvt Ltd)
• Sorakka Pichandi Parthipan (Nuray Chemicals Pvt Ltd)
• Murugan Arunkumar (Nuray Chemicals Pvt Ltd)
• Palaniswamy Premkumar (Nuray Chemicals Pvt Ltd)
• Salamuthu Kaliraj (Nuray Chemicals Pvt Ltd)
• Shanmugam Arumugam (Nuray Chemicals Pvt Ltd)
• Singavarapu Ajay Madhukar (Nuray Chemicals Pvt Ltd)
• Raman Silambarasan (Nuray Chemicals Pvt Ltd)
• Saminathan Karthick (Nuray Chemicals Pvt Ltd)
• Kudumudi Jayaraman Parthiban (Nuray Chemicals Pvt Ltd)
• Ravi Silambarasan (Nuray Chemicals Pvt Ltd)

Original assignee

Nuray Chemicals Pvt Ltd. Nuray Chemicals Pvt Ltd appears to be an active pharmaceutical manufacturing company based in India, involved in the production of active pharmaceutical ingredients (APIs). Their primary line of business is pharmaceutical manufacturing. It is unclear if they shipped a product embodying the claims of US11623920B2. As of the current date, Nuray Chemicals Pvt Ltd is operating.

Assignment timeline

• 2022-06-03 (executed) / recorded 2022-06-03 — Reel 059523/0488
  • Conveyance: Assignment
  • Assignor: Murugan Arunkumar, Paramanandam Senthilkumaran, Raman Silambarasan, Shanmugam Arumugam, Guttha Jayaprasad, Saminathan Karthick, Singavarapu Ajay Madhukar, Kudumudi Jayaraman Parthiban, Sorakka Pichandi Parthipan, Palaniswamy Premkumar, Manniyam Kailasam Selvam, Ravi Silambarasan, Ramasamy Venkatragavan, Salamuthu Kaliraj, Erugu Balaiah, Not Krishnareddy
  • Assignee: Nuray Chemicals Private Limited
  • Correspondent: Jeffrey M. Dean, Dean & Associates, PLLC, 12200 E. Briarwood Ave. Suite 175, Centennial, CO 80112. This correspondent also appears on other patent assignments.
  • Context: Transfer of inventor interest to the original assignee.
• 2026-01-23 (executed) / recorded 2026-02-09 — Reel 065849/0569
  • Conveyance: Assignment
  • Assignor: NURAY CHEMICALS PRIVATE LTD.
  • Assignee: Novitium Pharma LLC
  • Correspondent: Matthew F. Warburton, Caldwell Intellectual Property Law, 1333 Broadway, Suite 1000, Oakland, CA 94612.
  • Context: Acquisition of patent rights.

Timeline diagram

timeline
    title Ownership of US 11623920
    2022 : Inventors to Nuray Chemicals Pvt Ltd
    2023 : Issued
    2026 : Nuray Chemicals to Novitium Pharma LLC

NPE / troll-pattern signals

1. Shell-entity transfer — not present. Nuray Chemicals Pvt Ltd is an operating pharmaceutical company. Novitium Pharma LLC also appears to be an operating pharmaceutical company.
2. Known asserter in the chain — not present. Neither Nuray Chemicals Pvt Ltd nor Novitium Pharma LLC are recognized on common NPE lists.
3. Repeat correspondent across the chain — present. Jeffrey M. Dean of Dean & Associates, PLLC (Reel 059523/0488) has handled assignments for other patents. Matthew F. Warburton of Caldwell Intellectual Property Law (Reel 065849/0569) is not flagged as a repeat correspondent in this specific chain, but his firm has been noted in other contexts.
4. Cascading transfers — not present. Only two assignments are recorded, with a significant time gap between them.
5. Pre-litigation transfer — not present. There are no known litigation records for this patent as of the analysis date.
6. Bankruptcy fire-sale — not present. No indication of bankruptcy for Nuray Chemicals Pvt Ltd.
7. Privateering — unclear. No public information suggests privateering activity.
8. Defensive aggregator (anti-NPE) — not present. The patent is not currently assigned to a known defensive aggregator.

Verdict

Insufficient data. While one correspondent has appeared in other assignments, this is not strong enough to categorize the chain as an NPE. The current assignee, Novitium Pharma LLC, appears to be an operating company. Without additional information such as litigation history or further assignments to known NPEs, there is insufficient evidence to confidently classify this patent as being asserted by an NPE.

The most relevant prior art for US patent 11623920B2, based on the provided patent text, is identified and analyzed below. The patent's independent Claim 1 covers a crystalline form of pitolisant hydrochloride sesquihydrate, characterized by specific PXRD peaks.

Most Relevant Prior Art for US11623920B2

The patent US11623920B2 explicitly discusses several prior art references in its "BACKGROUND" section. Among these, some directly relate to the preparation and forms of pitolisant and its salts.

1. Meier et al.

• Full Citation: The patent text refers to "Meier" disclosing a process for preparing pitolisant hydrochloride. While a specific patent number for Meier is not provided directly in the background text, it describes a "three step process for preparing pitolisant hydrochloride starting with piperidine and 3-chloropropanol... to give pitolisant (1) which is finally reacted with gaseous hydrochloric acid to obtain pitolisant hydrochloride".
• Publication/Filing Date: Not explicitly stated in the provided text.
• Brief Description: Meier's process describes the chemical synthesis of pitolisant, followed by its conversion to pitolisant hydrochloride using gaseous hydrochloric acid. This process is noted to utilize sodium hydride (NaH), a hazardous reagent.
• Potential Anticipation (35 U.S.C. § 102): Meier's disclosure describes the preparation of pitolisant hydrochloride. However, it does not explicitly mention or characterize the specific crystalline sesquihydrate form defined by the unique PXRD peaks in Claim 1 of US11623920B2. Therefore, while it anticipates the compound pitolisant hydrochloride, it does not appear to anticipate the specific crystalline sesquihydrate solid-state form as claimed in Claim 1, which is defined by its PXRD pattern.

2. Raga et al.

• Full Citation: The patent states, "Raga discloses a crystalline form of pitolisant monohydrochloride having a moisture content of 2.7 to 6.5% and its preparation thereof." A specific patent number for Raga is not provided in the background text.
• Publication/Filing Date: Not explicitly stated in the provided text.
• Brief Description: Raga discloses a crystalline form of pitolisant monohydrochloride with a specified moisture content range (2.7 to 6.5%).
• Potential Anticipation (35 U.S.C. § 102): Raga describes a crystalline form of pitolisant monohydrochloride. However, Claim 1 of US11623920B2 specifically claims a sesquihydrate form (x=1.5, implying a water content of about 7.7% w/w as described in the patent) characterized by distinct PXRD peaks. The moisture content range disclosed by Raga (2.7 to 6.5%) is different from the sesquihydrate's water content (approx. 7.7% w/w). Additionally, Raga does not provide the specific PXRD peaks that characterize the crystalline form of Claim 1 (5.3, 7.3, 10.0, 11.8, and 26.1 ±0.2° two-theta). Therefore, Raga's disclosure does not appear to anticipate the specific pitolisant hydrochloride sesquihydrate form of Claim 1.

3. Sallarés et al.

• Full Citation: The patent states, "Sallarés discloses a process for preparing pitolisant (1) by forming the sodium salt of 3-(piperidin-1-yl)propan-1-ol (2) by reaction with sodium hydride (NaH), and then reacting the sodium salt with 3-(4-chlorophenyl)propyl methanesulfonate (3)". A specific patent number for Sallarés is not provided in the background text.
• Publication/Filing Date: Not explicitly stated in the provided text.
• Brief Description: Sallarés describes a process for preparing pitolisant (the free base), also utilizing sodium hydride.
• Potential Anticipation (35 U.S.C. § 102): Similar to Meier, Sallarés focuses on the synthesis of pitolisant free base using a hazardous reagent (NaH). It does not disclose the conversion to pitolisant hydrochloride, let alone the specific sesquihydrate crystalline form claimed in US11623920B2, nor any specific PXRD characteristics. Thus, it does not anticipate Claim 1.

4. Colombano et al.

• Full Citation: The patent states, "Colombano discloses a process for preparing pitolisant (1) by reacting 4-azaspiro[3.5]nonan-4-ium bromide (4) with 3-(4-chlorophenyl)propan-1-ol (5)." A specific patent number for Colombano is not provided in the background text.
• Publication/Filing Date: Not explicitly stated in the provided text.
• Brief Description: Colombano describes another process for preparing pitolisant free base.
• Potential Anticipation (35 U.S.C. § 102): Colombano describes a different route to pitolisant free base and does not disclose the hydrochloride salt or any specific crystalline forms of it. Therefore, it does not anticipate Claim 1.

5. Sefinovic et al. (EP 3 239 138 A1)

• Full Citation: EP 3 239 138 A1, "Hydrogen fumarate salt of 1-[3-[3-(4-chlorophenyl)propoxy]propyl]-piperidine, published on Nov. 1, 2017 to Stefinovic et al. of Sandoz AG (“Sefinovic”)."
• Publication/Filing Date: Published on November 1, 2017.
• Brief Description: Sefinovic discloses a hydrogen fumarate salt of pitolisant and a process for its preparation.
• Potential Anticipation (35 U.S.C. § 102): Sefinovic specifically discloses a fumarate salt of pitolisant, not the hydrochloride salt and certainly not the sesquihydrate crystalline form defined in Claim 1 of US11623920B2 by its specific PXRD pattern. Therefore, it does not anticipate Claim 1.

Conclusion on Anticipation for Claim 1:

Based on the descriptions provided in US11623920B2 itself, none of the cited prior art explicitly discloses a crystalline form of pitolisant hydrochloride sesquihydrate characterized by the specific PXRD peaks (5.3, 7.3, 10.0, 11.8, and 26.1 ±0.2° two-theta) as defined in independent Claim 1. While Meier and Raga mention pitolisant hydrochloride or its crystalline forms, they do not provide the detailed characterization (specifically the PXRD data and precise hydration state) that would directly anticipate the claimed sesquihydrate form. The other references (Sallarés, Colombano, Sefinovic) describe different salts or processes for the free base, and thus are even less likely to anticipate the specific crystalline form of pitolisant hydrochloride sesquihydrate.### Most Relevant Prior Art for US11623920B2

The provided patent text for US11623920B2 details several prior art references, primarily focusing on the synthesis of pitolisant and its various salts. The most relevant prior art documents that discuss pitolisant hydrochloride or other solid forms are analyzed below, particularly in relation to independent Claim 1 of US11623920B2, which covers a crystalline form of pitolisant hydrochloride sesquihydrate characterized by specific PXRD peaks.

1. Meier et al.

• Full Citation: While a specific patent number is not provided in the background section, the patent refers to "Meier" disclosing a process for preparing pitolisant hydrochloride.
• Publication/Filing Date: Not explicitly stated in the provided text.
• Brief Description: Meier's process involves a three-step synthesis, starting with piperidine and 3-chloropropanol, to yield 3-(piperidin-1-yl)propan-1-ol, which is then reacted with 3-(4-chlorophenyl)propyl methanesulfonate in the presence of sodium hydride (NaH) to give pitolisant. This pitolisant is then reacted with gaseous hydrochloric acid to obtain pitolisant hydrochloride.
• Potential Anticipation (35 U.S.C. § 102): Meier's disclosure anticipates the compound pitolisant hydrochloride itself. However, independent Claim 1 of US11623920B2 specifically claims a crystalline pitolisant hydrochloride sesquihydrate defined by a unique set of PXRD peaks (5.3, 7.3, 10.0, 11.8, and 26.1 ±0.2° two-theta). The Meier disclosure, as described, does not provide any characterization of a specific crystalline form, nor does it mention a sesquihydrate or its PXRD pattern. Therefore, it does not directly anticipate the specific crystalline form of Claim 1.

2. Raga et al.

• Full Citation: The patent refers to "Raga" disclosing a crystalline form of pitolisant monohydrochloride. A specific patent number for Raga is not provided in the background section.
• Publication/Filing Date: Not explicitly stated in the provided text.
• Brief Description: Raga discloses a crystalline form of pitolisant monohydrochloride that has a moisture content ranging from 2.7 to 6.5%.
• Potential Anticipation (35 U.S.C. § 102): Raga describes a crystalline form of pitolisant monohydrochloride. However, Claim 1 of US11623920B2 claims a sesquihydrate (x=1.5), which has a water content of approximately 7.7% w/w according to the detailed description of US11623920B2. This moisture content differs from Raga's disclosed range of 2.7 to 6.5%. Furthermore, Raga's disclosure, as presented, does not provide the specific PXRD peaks that define the sesquihydrate form of Claim 1. Without this specific structural characterization, Raga does not directly anticipate the crystalline pitolisant hydrochloride sesquihydrate claimed in US11623920B2.

3. Sallarés et al.

• Full Citation: The patent refers to "Sallarés" disclosing a process for preparing pitolisant (1). A specific patent number for Sallarés is not provided in the background section.
• Publication/Filing Date: Not explicitly stated in the provided text.
• Brief Description: Sallarés describes a process for preparing pitolisant (the free base) by forming the sodium salt of 3-(piperidin-1-yl)propan-1-ol with sodium hydride (NaH) and then reacting it with 3-(4-chlorophenyl)propyl methanesulfonate.
• Potential Anticipation (35 U.S.C. § 102): This reference describes the preparation of the pitolisant free base and does not mention its conversion to the hydrochloride salt, let alone a specific crystalline hydrate form. Therefore, it does not anticipate Claim 1.

4. Colombano et al.

• Full Citation: The patent refers to "Colombano" disclosing a process for preparing pitolisant (1). A specific patent number for Colombano is not provided in the background section.
• Publication/Filing Date: Not explicitly stated in the provided text.
• Brief Description: Colombano discloses a process for preparing pitolisant (the free base) by reacting 4-azaspiro[3.5]nonan-4-ium bromide with 3-(4-chlorophenyl)propan-1-ol.
• Potential Anticipation (35 U.S.C. § 102): Similar to Sallarés, this reference is directed to the synthesis of the pitolisant free base and does not disclose the hydrochloride salt or its specific crystalline forms. Therefore, it does not anticipate Claim 1.

5. Sefinovic et al.

• Full Citation: EP 3 239 138 A1, "Hydrogen fumarate salt of 1-[3-[3-(4-chlorophenyl)propoxy]propyl]-piperidine," published on November 1, 2017 to Stefinovic et al. of Sandoz AG.
• Publication/Filing Date: Published on November 1, 2017.
• Brief Description: Sefinovic discloses a hydrogen fumarate salt of pitolisant and a process for its preparation.
• Potential Anticipation (35 U.S.C. § 102): This reference describes a fumarate salt of pitolisant, which is a different chemical entity from the hydrochloride salt. It does not disclose pitolisant hydrochloride, nor its sesquihydrate form or associated PXRD data. Therefore, it does not anticipate Claim 1.

Summary of Anticipation for Claim 1:

While the prior art cited in US11623920B2's background discloses the general compound pitolisant hydrochloride or processes for making pitolisant free base, none of them explicitly describe or characterize the specific crystalline form of pitolisant hydrochloride sesquihydrate by its unique PXRD peaks (5.3, 7.3, 10.0, 11.8, and 26.1 ±0.2° two-theta) as defined in independent Claim 1. Therefore, based on the provided patent text, these prior art references do not appear to directly anticipate Claim 1 under 35 U.S.C. § 102.

Obviousness Analysis of US Patent 11,623,920 under 35 U.S.C. § 103

This analysis addresses the obviousness of US Patent 11,623,920 under 35 U.S.C. § 103, focusing on Independent Claim 1, which defines a specific crystalline form of pitolisant hydrochloride. For an invention to be obvious, a person having ordinary skill in the art (PHOSITA) would have been motivated to combine prior art references with a reasonable expectation of success, leading to the claimed invention.

Independent Claim 1 of US Patent 11,623,920

Independent Claim 1 protects pitolisant hydrochloride sesquihydrate, characterized by specific Powder X-ray Diffraction (PXRD) peaks at 5.3, 7.3, 10.0, 11.8, and 26.1 ±0.2° two-theta. This form is a hydrate, meaning it incorporates 1.5 molecules of water per molecule of pitolisant hydrochloride. The patent indicates this sesquihydrate has a water content of about 7.7% w/w. [cite: "One aspect relates to pitolisant hydrochloride of Formula-(II), where x is 1.5. For this aspect, the pitolisant hydrochloride of Formula-(II) (viz., pitolisant hydrochloride sesquihydrate) has a water content of about 7.7% w/w."]

Prior Art References and Their Disclosures

The relevant prior art references disclosed within US11623920B2 for this analysis include:

1. Schwartz: Discloses a process for preparing pitolisant and its pharmaceutically acceptable salts, including pitolisant hydrochloride. [cite: "Schwartz discloses a process for preparing pitolisant and its pharmaceutically acceptable salts such as hydrochloride, hydrobromide, hydrogen maleate, and hydrogen oxalate."] This establishes that pitolisant hydrochloride itself is a known compound.
2. Meier: Discloses a three-step process for preparing pitolisant hydrochloride, reacting pitolisant (1) with gaseous hydrochloric acid to obtain pitolisant hydrochloride. [cite: "Meier discloses a three step process for preparing pitolisant hydrochloride starting with piperidine and 3-chloropropanol, to give the intermediate 3-(piperidin-1-yl)propan-1-ol (2), which is reacted with 3-(4-chlorophenyl)propyl methanesulfonate (3) in the presence of sodium hydride and 15-crown-5 to give pitolisant (1) which is finally reacted with gaseous hydrochloric acid to obtain pitolisant hydrochloride, as shown in Scheme-1."] This further confirms the existence and a method of preparing pitolisant hydrochloride.
3. Raga: Discloses "a crystalline form of pitolisant monohydrochloride having a moisture content of 2.7 to 6.5% and its preparation thereof." [cite: "Raga discloses a crystalline form of pitolisant monohydrochloride having a moisture content of 2.7 to 6.5% and its preparation thereof."] This is highly relevant as it teaches the existence of a crystalline form of pitolisant hydrochloride that contains moisture, strongly suggesting a hydrated form. The term "monohydrochloride" refers to the salt form (one HCl molecule), not necessarily a monohydrate. Given the molecular weight of pitolisant hydrochloride (~351.94 g/mol), a moisture content of 2.7% corresponds to approximately 0.53 moles of water, while 6.5% corresponds to approximately 1.27 moles of water. This range covers various hydrate possibilities, including hemihydrates, monohydrates, and potentially mixtures thereof. Raga also notes that pitolisant hydrochloride exhibits different properties (e.g., aqueous solubility and stability) compared to other salts. [cite: "Raga discloses that pitolisant hydrochloride exhibits different properties (e.g., aqueous solubility and stability) when compared to pitolisant oxalate and pitolisant maleate."]

Combination of Prior Art References and Motivation

A PHOSITA in the pharmaceutical field would be motivated to investigate and characterize different solid-state forms of known active pharmaceutical ingredients (APIs), such as pitolisant hydrochloride, for several reasons, including improving physicochemical properties (e.g., stability, solubility, dissolution rate, bioavailability), enhancing manufacturability, and extending intellectual property protection. The patent itself lists "to provide new solid-state forms of pitolisant and its pharmaceutically acceptable salts" as an objective. [cite: "Another objective of the present disclosure is to provide new solid-state forms of pitolisant and its pharmaceutically acceptable salts."]

The combination of Schwartz or Meier (establishing the known nature of pitolisant hydrochloride [cite: "Schwartz discloses a process for preparing pitolisant and its pharmaceutically acceptable salts such as hydrochloride...", "Meier discloses a three step process for preparing pitolisant hydrochloride... to obtain pitolisant hydrochloride"]) with Raga (teaching a crystalline form of pitolisant monohydrochloride with a moisture content of 2.7 to 6.5% [cite: "Raga discloses a crystalline form of pitolisant monohydrochloride having a moisture content of 2.7 to 6.5% and its preparation thereof."]) would lead a PHOSITA to explore various hydrated forms of pitolisant hydrochloride. Raga's explicit disclosure of moisture content in a crystalline form directly points towards the existence and relevance of hydrates.

A PHOSITA would routinely screen for different hydration states of an API, using conventional methods such as recrystallization from aqueous or mixed aqueous/organic solvents, controlled humidity studies, and varying drying conditions. The patent itself describes a method for preparing hydrate forms of pitolisant hydrochloride by dissolving it in water or a water/organic solvent mixture, followed by solvent removal through techniques like evaporation, spray drying, or freeze drying. [cite: "In one more embodiment of the present disclosure provides a method for preparing hydrate forms of pitolisant hydrochloride by dissolving pitolisant hydrochloride of Formula-(I) in water or mixture of water and organic solvent, optionally treating with carbon, filtering and precipitating the solid by adding solvent in which pitolisant hydrochloride is not soluble.", "In one more embodiment of the present disclosure provides a method for preparing a pitolisant hydrochloride hydrate form comprising a) providing a solution on pitolisant hydrochloride b) removing solvent from the reaction mass to obtain solid wherein the removal of solvent from the reaction mass is carried out by evaporation, spray drying, air drying, freeze drying, etc."] For instance, Example 12 describes preparing pitolisant hydrochloride sesquihydrate by simply spray drying an aqueous solution of pitolisant hydrochloride. [cite: "10 g of pitolisant hydrochloride was dissolved in 100 mL water, the obtained solution was filtered and the filtrate was spray dried to obtain pitolisant hydrochloride sesquihydrate."] This demonstrates the use of a conventional technique to obtain the claimed form.

Given Raga's disclosure of a crystalline form with moisture (2.7-6.5% w/w), which is close to or overlapping with the theoretical water content for a sesquihydrate (~7.13% w/w) and the patent's disclosed 7.7% w/w, the discovery of a pitolisant hydrochloride sesquihydrate would be a predictable outcome of routine experimentation by a PHOSITA. The specific PXRD peaks, while characterizing the claimed form, represent a routine characterization of a discovered hydrate rather than an unexpected structural discovery. Without evidence of unexpected advantageous properties of the sesquihydrate over other known or readily discoverable hydrated forms (e.g., Raga's crystalline form), merely identifying a new PXRD pattern for a predictable hydrate would not overcome an obviousness challenge. The patent does not present evidence of such unexpected properties for the sesquihydrate specifically.

Conclusion

Independent Claim 1 of US Patent 11,623,920, claiming pitolisant hydrochloride sesquihydrate characterized by specific PXRD peaks, would likely be considered obvious under 35 U.S.C. § 103. This is based on the combination of prior art references Schwartz and/or Meier (teaching the known compound pitolisant hydrochloride [cite: "Schwartz discloses a process for preparing pitolisant and its pharmaceutically acceptable salts such as hydrochloride...", "Meier discloses a three step process for preparing pitolisant hydrochloride... to obtain pitolisant hydrochloride"]) with Raga (teaching a crystalline form of pitolisant monohydrochloride with a moisture content of 2.7 to 6.5% [cite: "Raga discloses a crystalline form of pitolisant monohydrochloride having a moisture content of 2.7 to 6.5% and its preparation thereof."]). A PHOSITA would be motivated to investigate and characterize various hydrated forms of pitolisant hydrochloride, and discovering the sesquihydrate through conventional methods would be a predictable result of such routine experimentation, especially since Raga's disclosure already points to hydrated forms.

For US Patent 11,623,920, here's a detailed breakdown of its term and related applications:

Patent Term Adjustment (PTA)

Patent Term Adjustment (PTA) compensates for certain administrative delays by the USPTO during patent prosecution, adding days to the patent's 20-year term from its earliest filing date. While the specific PTA amount for US 11,623,920 is not directly stated in the provided text, the USPTO automatically determines and provides this information by the patent's issue date. Applicants have a window to request reconsideration of the PTA determination.

Patent Term Extension (PTE)

Patent Term Extension (PTE) is granted to compensate patent owners for delays incurred in obtaining regulatory approval for certain products, primarily pharmaceuticals, from agencies like the FDA. The provided patent text does not indicate if US 11,623,920 has received or is eligible for PTE. Typically, PTE applies to one patent per regulatory review period and is limited to a maximum of five years, with the total patent life not exceeding 14 years from FDA approval.

Continuation Applications

The patent text explicitly states a priority claim to US 18/174,238, filed on February 24, 2023. This indicates that US 18/174,238 is a related application, and given the later filing date relative to the priority applications (Indian Patent Application Nos. 202141025328, 202141035609, 202141046743, and 202241009416), it could potentially be a continuation, divisional, or continuation-in-part of another application in the family, or a new application claiming priority from the Indian applications. However, the exact type of relationship (e.g., continuation, divisional) to this specific US patent 11623920 is not definitively stated in the provided text beyond being a priority claim.

Divisional Applications

The provided patent text does not explicitly mention any divisional applications directly stemming from US 11,623,920.

Related Family Members

The patent claims priority to the following Indian Patent Application Nos.:

• 202141025328, filed on June 7, 2021
• 202141035609, filed on August 6, 2021
• 202141046743, filed on October 13, 2021
• 202241009416, filed on February 22, 2022

Additionally, a priority claim is made to US 18/174,238, filed on February 24, 2023. These constitute the related family members for this patent.

Projected Expiration Date

The anticipated expiration date for US Patent 11,623,920 is May 24, 2042. This date is typically calculated as 20 years from the earliest filing date of the application, subject to any Patent Term Adjustments (PTA) or extensions. The filing date of the application that led to US 11,623,920 was May 24, 2022.