US 12370153

US Patent 12370153, titled "Ready-to-use ketamine premix formulation," was issued on July 29, 2025 [cite: Publication date 2025-07-29]. The patent was filed on July 11, 2024, under application number US18/770,514 [cite: Filing date 2024-07-11]. The inventor is Sergio Dusci, and the current assignee is Inforlife SA [cite: Inventor Sergio Dusci, Current Assignee Inforlife SA].

Abstract:
The invention describes a sterile, ready-to-use, and stable aqueous solution of ketamine designed for direct intravenous infusion. This premixed formulation is contained within a sealed infusion container and is notable for being free of antimicrobials like benzethonium chloride, while maintaining a long shelf-life. It is intended for use in patients requiring anesthesia for diagnostic or surgical procedures.

Plain-Language Overview of Independent Claims:

• Claim 1: This claim covers a ready-to-use, sterile ketamine product. It includes an aqueous ketamine solution with a concentration between approximately 0.5 to 2.5 mg/mL, a tonicity adjusting agent, a pH adjusting agent, and water for injection. A key feature is that the ketamine solution does not contain benzethonium chloride.
• Claim 35: This claim describes a ready-to-use ketamine product that is contained in a terminally sterilized infusion container. The product consists of an aqueous ketamine solution with a concentration of about 0.5 to 2.5 mg/mL, a tonicity adjusting agent, a pH adjusting agent, and water for injection, and is specifically free of preservatives.

Litigation Information:
The patent family has pending litigation, specifically a PTAB (Patent Trial and Appeal Board) case identified as PGR2026-00036 [cite: PTAB case PGR2026-00036 filed (Pending), https://portal.unifiedpatents.com/ptab/case/PGR2026-00036]. No specific dockets for US12370153 in the CAFC (Court of Appeals for the Federal Circuit) 2026 dockets were found in the provided search results.

As of April 26, 2026, there is one known litigation case involving US patent 12370153:

1. PTAB Case PGR2026-00036

• Plaintiff(s): The petitioner is not explicitly named in the available snippets for PGR2026-00036, but unifiedpatents.com lists Merck Sharp & Dohme LLC as a petitioner in other PGR cases with similar numbering (e.g., PGR2026-00027, PGR2025-00087). However, without direct confirmation for PGR2026-00036, the specific petitioner remains unconfirmed.
• Defendant(s): Inforlife SA (patent owner)
• Jurisdiction: Patent Trial and Appeal Board (PTAB)
• Case Number: PGR2026-00036
• Filing Date: April 2, 2026
• Outcome or Current Status: Pending

The search results indicate that PGR2026-00036 is filed against US Patent No. 12370153. However, some search results (especially) seem to conflate PGR2026-00036 with other PGRs (PGR2026-00039, PGR2025-00085, PGR2026-00026) and different patent numbers (12,168,036 and 12,305,206). It's crucial to stick to the provided patent number (US12370153) and the specific PGR (PGR2026-00036).

From the provided structured data:

• PGR2026-00036
• filed: 2026-03-25
• last modified: 2026-04-15
• status: Pending
• petitioner: Par Health, Inc.
• inventor: Sergio DUSCI

From search results and:

• PGR2026-00036 is indeed for Patent # 12370153 (PO/Respondent Patent #. 12370153).
• Petition Filing Date: 2026 Mar 25.
• Trial Status: Pending.
• Institution Decision Date: - (empty, meaning not yet decided).
• Latest Decision Date: - (empty, meaning not yet decided).
• Termination Date: - (empty, meaning not yet decided).

The search results did not provide specific details on:

• Judge panel
• Petition grounds (which claims, what art, what statutory basis) - though mentions "obviousness and lack of written description under 35 U.S.C. § 112" for another patent (12,168,036) and a different PGR (PGR2026-00039). I need to be careful not to attribute this to PGR2026-00036. I will state that the specific grounds are not publicly available in the search results.
• Institution decision details (as it's pending).
• Settlement/termination.
• Appeal.

Given that the PGR was filed on 2026-03-25, the institution decision deadline would be 6 months from this date, approximately 2026-09-25.

I need to make sure I don't attribute information about other PGRs or patents to PGR2026-00036 and US12370153. The key is that the searches did not return specific claims challenged, prior art, or judge panel for this specific PGR. I should explicitly state this lack of information.

Updated plan:

1. Proceedings overview: One pending PGR.
2. For PGR2026-00036:
   • Type: Post-Grant Review
   • Filed: 2026-03-25 (from structured data, confirmed by)
   • Status: Pending.
   • Judge panel: Not publicly available yet.
   • Petition grounds: Specific claims and grounds are not yet publicly detailed in the provided search results.
   • Institution decision: Pending. The deadline is approximately 2026-09-25 (6 months from filing date).
   • Final Written Decision: Not applicable.
   • Settlement / termination: Not applicable.
   • Appeal: Not applicable.
   • Defensive value: Pending PGR creates uncertainty; monitoring is key.
3. Strategic summary:
   • Claims are all untested by FWD.
   • Estoppel not yet in effect.
   • Only one proceeding, so no "pattern signals" beyond that.
4. Recommended next steps: Monitor institution decision deadline.## Proceedings overview

One Post-Grant Review (PGR) proceeding, PGR2026-00036, is currently on file and pending for US patent 12370153. This means that the patent's validity is currently being challenged before the Patent Trial and Appeal Board (PTAB), and no claims have yet been affirmed or invalidated through this process. For a defendant, this presents an uncertain defensive posture, as the outcome of the PGR could significantly alter the enforceability of the patent.

PGR2026-00036 — Par Health, Inc. v. Inforlife SA

• Type: Post-Grant Review
• Filed: 2026-03-25
• Status: Pending — The proceeding is active and awaiting an institution decision from the PTAB.
• Judge panel: The specific judge panel for this pending proceeding is not yet publicly available in the provided search results.
• Petition grounds: The specific claims challenged, prior art asserted, and statutory bases (§ 102 / § 103 / § 112) for this particular petition are not detailed in the provided search results.
• Institution decision: Pending. The PTAB has a statutory deadline of six months from the petition filing date to issue a decision on whether to institute the trial. Therefore, an institution decision is expected around 2026-09-25. The institution rate for IPRs and PGRs has seen a downward trend, with fiscal year 2026 year-to-date institution rates at 37% as of February 2026, and the USPTO Director has emphasized considering factors such as domestic manufacturing activity when deciding institution.
• Final Written Decision: Not applicable, as the proceeding is pending and has not yet reached the final written decision stage.
• Settlement / termination: Not applicable, as the proceeding is pending.
• Appeal: Not applicable, as no final decision has been rendered.
• Defensive value: As this PGR is pending, all claims of US12370153 remain untested by a final PTAB decision. The outcome of the institution decision, expected around September 2026, will be critical. If instituted, the patent's claims will face a direct challenge, potentially leading to invalidation. If institution is denied, the patent owner's position will be strengthened, making future PTAB challenges harder on similar grounds.

Strategic summary

Currently, all claims of US patent 12370153 are UNTESTED by a Final Written Decision from the PTAB. The single pending PGR, PGR2026-00036, means that the enforceability of the patent claims is currently under scrutiny. There is no existing record of claims being canceled or sustained by the PTAB for this patent.

The estoppel landscape has not yet formed for this patent. If PGR2026-00036 is instituted and proceeds to a Final Written Decision, the petitioner (Par Health, Inc.) and its privies would be estopped from raising in district court or the ITC any ground they raised or reasonably could have raised during the PGR, with respect to any claims that were subject to the FWD. However, since the proceeding is pending, these estoppel provisions are not yet in effect. For other potential defendants, prior art grounds remain available for challenge, subject to the statutory requirements and discretionary denial factors recently emphasized by the USPTO Director.

There are no apparent pattern signals beyond the single PGR filing. This suggests that while a challenger has emerged, there isn't yet a history of serial attacks or aggressive defensive maneuvers by the patent owner at the PTAB.

Recommended next steps

Given that PGR2026-00036 is pending, the most crucial next step for a defendant facing assertion of US12370153 is to actively monitor the status of this proceeding. The institution decision deadline is approaching, expected around 2026-09-25. This decision will significantly impact the patent's strength. Monitoring the PTAB's Public Search facility for updates on PGR2026-00036 is advisable.

Inventors

• Sergio Dusci: Employer not explicitly stated at the time of filing (2024-07-11). He assigned his interest to Inforlife SA.

Original assignee

The original assignee listed on the patent is Inforlife SA.

• Products: The patent describes a "Ready-to-use ketamine premix formulation" for direct intravenous infusion. It is unclear from the patent text alone if Inforlife SA currently ships this specific product.
• Primary Line of Business: Based on the patent, their primary business appears to be in developing pharmaceutical formulations, specifically ready-to-use injectable drug products.
• Current Status: Inforlife SA appears to be an active entity, as it is listed as the current assignee and involved in pending litigation.

Assignment timeline

No assignment records were found for US patent 12370153 at the USPTO Patent Assignment Search website (https://assignmentcenter.uspto.gov/) as of 2026-05-29.

However, Google Patents lists one assignment event:

• 2024-07-12 / recorded N/A (Google Patents does not provide recording date or reel/frame for this specific event)
  • Conveyance: Assignment of Assignor's Interest
  • Assignor: DUSCI, SERGIO
  • Assignee: InfoRLife SA
  • Correspondent: Not specified in Google Patents event data.
  • Context: Transfer from individual inventor to the company that filed the patent application. This is a common practice where the inventor assigns their rights to their employer or the entity sponsoring the research.

Given the absence of records on the USPTO Assignment Center, any subsequent transfers of ownership are not publicly recorded with the USPTO. The Google Patents entry for "2024-07-12: Assigned to InfoRLife SA" likely refers to the initial assignment from the inventor to the assignee, which may or may not be formally recorded in the public assignment database by reel/frame, or may be recorded with the application as part of the initial filing. Without a reel/frame, it cannot be confirmed via the USPTO Assignment Center.

Timeline diagram

timeline
    title Ownership of US 12370153
    2024 : Filed by Inforlife SA
         : Inventor Sergio Dusci assigned to Inforlife SA (per Google Patents)
    2025 : Patent issued to Inforlife SA
    2026 : PTAB case PGR2026-00036 filed

NPE / troll-pattern signals

1. Shell-entity transfer — Not present. There are no recorded transfers to entities with names suggesting a shell company or to known registered agent addresses in the USPTO Assignment Center. The only documented transfer is from the individual inventor to the corporate assignee.
2. Known asserter in the chain — Not present. The current assignee, Inforlife SA, is not listed as a known NPE/patent asserter based on the provided data or common public lists.
3. Repeat correspondent across the chain — Not present. No assignment records are available from the USPTO Assignment Center to identify any correspondents.
4. Cascading transfers — Not present. There are no multiple consecutive assignments recorded.
5. Pre-litigation transfer — Not present. No assignments are recorded within six months of the PGR2026-00036 filing date (April 2, 2026).
6. Bankruptcy fire-sale — Not present. No evidence suggests Inforlife SA has filed for bankruptcy or that the patent was sold in such proceedings.
7. Privateering — Unclear. There is no public information provided to indicate if Inforlife SA is asserting this patent on behalf of another operating company.
8. Defensive aggregator (anti-NPE) — Not present. The patent is currently owned by Inforlife SA, which is not a known defensive aggregator.

Verdict

Insufficient data.
The USPTO Assignment Center shows no recorded assignments for US12370153. While Google Patents indicates an initial assignment from the inventor to Inforlife SA, this is a standard practice and does not signal NPE activity. Without a chain of recorded assignments, there is insufficient data to identify any NPE or patent-troll patterns. Verification can be performed by searching the USPTO Assignment Center for US12370153 (https://assignmentcenter.uspto.gov/patent/index.html?pno=US12370153).

To identify the most relevant prior art for US patent 12370153, I will search the USPTO database for the patent and examine its cited references.

USPTO Search for US12370153B2:

A search for patent number 12370153 on the USPTO website leads to information about the patent, including its citations.

Most Relevant Prior Art for US12370153B2:

The patent text for US12370153B2 explicitly references two U.S. Patents as prior art in the context of terminal sterilization of ketamine formulations: U.S. Pat. Nos. 5,439,643 and 8,617,467.

Here's a breakdown of these references:

1. U.S. Patent No. 5,439,643

   • Full Citation: U.S. Pat. No. 5,439,643. (No title or dates are provided in the patent text or search snippets, so these details cannot be accurately presented at this time. An in-depth search for this patent number would be required to extract this information fully).
   • Publication/Filing Date: Not explicitly provided in the current search results.
   • Brief Description: This patent is cited within US12370153B2 in the context of terminal sterilization methods for ketamine formulations in infusion bags, specifically mentioning steam sterilization, heat sterilization (like autoclaving), radiation, or chemical sterilization (e.g., ethylene oxide).
   • Potential Anticipated Claim(s) under 35 U.S.C. § 102: Given its citation for terminal sterilization methods, it could potentially anticipate aspects of claims related to the method of preparing the ketamine product. Specifically, claims 48, 49, 50, 51, 52, and 53, which detail the terminal sterilization steps (including autoclaving) in the preparation method, could be implicated.

2. U.S. Patent No. 8,617,467

   • Full Citation: U.S. Pat. No. 8,617,467. (No title or dates are provided in the patent text or search snippets, so these details cannot be accurately presented at this time. An in-depth search for this patent number would be required to extract this information fully).
   • Publication/Filing Date: Not explicitly provided in the current search results.
   • Brief Description: Similar to U.S. Pat. No. 5,439,643, this patent is cited in US12370153B2 for its relevance to various terminal sterilization techniques for ketamine formulations in infusion bags, including steam, heat (autoclave), radiation, or chemical sterilization.
   • Potential Anticipated Claim(s) under 35 U.S.C. § 102: Like U.S. Pat. No. 5,439,643, this patent could potentially anticipate claims 48, 49, 50, 51, 52, and 53, which cover the method of preparing the ketamine product through terminal sterilization.

Without access to the full text of US 5,439,643 and US 8,617,467, a more detailed analysis of their descriptions and a definitive determination of which specific claims of US12370153B2 they potentially anticipate under 35 U.S.C. § 102 is not possible.

Obviousness Analysis under 35 U.S.C. § 103

A patent claim is obvious under 35 U.S.C. § 103 if the differences between the claimed invention and the prior art are such that the subject matter as a whole would have been obvious at the time the invention was made to a person having ordinary skill in the art (POSA). This analysis considers what a POSA would have been motivated to combine or modify existing prior art to arrive at the claimed invention, with a reasonable expectation of success.

The priority date of US Patent 12370153 is July 12, 2023 [cite: Prior art date 2023-07-12]. Therefore, any prior art publicly available before this date can be considered.

Independent Claim 1 Analysis:

Claim 1 covers a ready-to-use, sterile ketamine product comprising an aqueous ketamine solution (0.5 to 2.5 mg/mL), a tonicity adjusting agent, a pH adjusting agent, and water for injection, notably free of benzethonium chloride. [cite: Claim 1]

Combination of Prior Art References:

A strong argument for obviousness of Claim 1 can be made by combining the teachings of Biomed (New Zealand data sheet, June 15, 2021) and Ketalar (FDA label), potentially supplemented by general knowledge in the art as represented in references like Remington's Pharmaceutical Sciences.

1. Biomed (New Zealand data sheet, June 15, 2021):

   • Biomed discloses a "ready-to-use" 100 mg/100 mL (1 mg/mL) ketamine solution for infusion packaged in a flexible IV bag with an overwrap.
   • The solution contains sodium chloride as a tonicity adjusting agent.
   • It is explicitly described as "preservative-free."
   • It has a pH of 3.5-5.5.
   • It has a shelf-life of 24 months when stored at or below 25°C.
   • The petitioner in PGR2026-00036 argued that Biomed discloses every limitation of challenged independent and dependent claims, including concentration, composition, pH, sterility, RTU status, and shelf-life. They further contended that other claimed features, such as the osmolality of 270-330 mOsmol/kg and chemical stability, were inherent properties of Biomed's isotonic, stable formulation.

2. Ketalar (FDA label):

   • Ketalar is a commercially available ketamine hydrochloride injection, formulated as a slightly acidic (pH 3.5-5.5) sterile solution.
   • It comes in concentrations of 10, 50, or 100 mg ketamine base per milliliter.
   • It explicitly states that it "contains not more than 0.1 mg/mL Phemerol® (benzethonium chloride) added as a preservative."
   • The label describes dilution instructions to prepare solutions containing 1 mg/mL or 2 mg/mL ketamine for intravenous infusion using 5% Dextrose Injection, USP or Sodium Chloride (0.9%) Injection, USP.

Motivation to Combine and Expectation of Success:

A POSA, at the time of the invention, would have been motivated to combine the teachings of Biomed and Ketalar for several reasons:

• Desire for preservative-free, ready-to-use formulations: The background of US12370153 explicitly states a need for "sterile, ready to use infusion container comprising a shelf-stable, liquid formulation of ketamine that does not contain a preservative or antimicrobial such as benzethonium chloride." This demonstrates a recognized problem in the art regarding the undesirability of benzethonium chloride due to its known toxicity. NRx Pharmaceuticals also filed a Citizen Petition with the FDA seeking removal of benzethonium chloride from ketamine products due to its toxicity.
• Existing dilution practices: Ketalar's instructions for diluting concentrated ketamine vials (e.g., 50 mg/mL or 100 mg/mL) to 1 mg/mL or 2 mg/mL in saline or dextrose for IV infusion clearly show that the desired final concentrations for administration were already known and practiced.
• Convenience and safety of ready-to-use: The inventors of US12370153 themselves state that "premixed formulations therefore avoid the cost, inconvenience, and risk of contamination or overdose that can be associated with reconstituting or diluting a concentrated ketamine formulation prior to administration to a patient." This motivation to provide ready-to-use formulations to minimize preparation errors and contamination is a well-known objective in pharmaceutical compounding.
• Biomed as a direct example: Biomed directly teaches a "ready-to-use," "preservative-free" ketamine solution at a concentration of 1 mg/mL, with an appropriate pH and tonicity, packaged in an IV bag, and having a long shelf-life. A POSA, aware of the toxicity concerns of benzethonium chloride in Ketalar, would look for ways to achieve a ready-to-use, preservative-free version of the commonly administered concentrations. Biomed provides exactly this.
• Terminal Sterilization: The PGR petition argues that for claims requiring specific sterilization methods (e.g., "terminally sterilized" in claim 2), general pharmaceutical knowledge (e.g., from "Remington 2021") teaches that terminal sterilization and aseptic filling are standard, well-known, and obvious pathways for manufacturing sterile parenteral drug products. This suggests that achieving a sterile product without benzethonium chloride through terminal sterilization, once a stable preservative-free formulation (like Biomed's) is known, would be a predictable manufacturing choice. WO1994023711A1 also describes sterilizing sealed ampoules of ketamine at 121°C for 20 minutes.

Therefore, a POSA, motivated by the recognized problems of dilution errors and preservative toxicity, and the known advantages of ready-to-use formulations, would have found it obvious to combine the specific characteristics of the preservative-free, ready-to-use ketamine solution described in Biomed (concentration, tonicity agent, pH, absence of preservative, packaging in an IV bag, and shelf-life) with the widely known and desired administration concentrations (1-2 mg/mL) derived from diluting concentrated Ketalar. The expectation of success would be high given that Biomed already demonstrates the feasibility of a stable, preservative-free, ready-to-use ketamine solution.

Independent Claim 35 Analysis:

Claim 35 covers a preservative-free aqueous ketamine solution (0.5 to 2.5 mg/mL ketamine, tonicity adjusting agent, pH adjusting agent, and water for injection) contained in a terminally sterilized, ready-to-use infusion container. [cite: Claim 35]

Combination of Prior Art References:

Similar to Claim 1, the combination of Biomed (New Zealand data sheet, June 15, 2021) and general knowledge of terminal sterilization, as exemplified by references like Remington's Pharmaceutical Sciences or the practices described in WO1994023711A1, would render Claim 35 obvious.

1. Biomed (New Zealand data sheet, June 15, 2021):
   • As detailed above, Biomed provides a ready-to-use, preservative-free ketamine solution at relevant concentrations (1 mg/mL), with appropriate tonicity and pH, packaged in a flexible IV bag with an overwrap, and possessing a 24-month shelf-life. While Biomed doesn't explicitly state "terminally sterilized," it describes a "sterile" product. For a sterile, ready-to-use infusion product, terminal sterilization is a common and preferred method when feasible.
2. General Knowledge of Terminal Sterilization (e.g., Remington, WO1994023711A1, KETALAR ANDA #76-092):
   • Terminal sterilization (e.g., by autoclaving, steam, or heat) is a well-established and preferred method for sterilizing pharmaceutical products in their final sealed containers due to enhanced safety and reduced contamination risk.
   • The PGR petition explicitly states that "Remington 2021 taught these are the two standard, well-known, and obvious pathways for manufacturing any sterile parenteral drug product."
   • WO1994023711A1, a prior art document, describes sterile filtering a ketamine solution and then sterilizing the sealed ampoules at 121°C for 20 minutes, demonstrating the application of terminal sterilization to ketamine formulations.
   • The FDA approval for Ketamine Hydrochloride Injectable USP, 50 mg/mL in 10 mL vials (ANDA #76-092) from April 30, 2001, mentions "additional terminal sterilization validation on the 50 mg/mL, 10 mL package" to provide supportive information, indicating that terminal sterilization was a standard consideration for ketamine injections well before the priority date of US12370153.

Motivation to Combine and Expectation of Success:

A POSA would have been motivated to combine the features of Biomed with terminal sterilization for the following reasons:

• Established practice for sterile products: Terminal sterilization is a standard and often preferred method for achieving sterility in pharmaceutical products due to its robustness. Given Biomed's disclosure of a stable, preservative-free ketamine solution, a POSA would naturally consider applying terminal sterilization to this formulation to produce a sterile, ready-to-use product.
• Safety and convenience benefits: As discussed, terminal sterilization enhances safety by reducing contamination risks compared to aseptic filling alone. Combining this with the ready-to-use, preservative-free nature of the Biomed solution would further improve patient safety and convenience, addressing the recognized needs in the art.
• Known compatibility of ketamine with heat sterilization: Prior art, such as WO1994023711A1, explicitly demonstrates the use of heat sterilization (121°C for 20 minutes) for ketamine solutions. The present patent itself includes a thermal stress study on ketamine HCL injection subjected to autoclave cycles, with results shown in tables 22 and 23, suggesting that ketamine's stability under thermal stress was investigated and manageable. This would provide a POSA with a reasonable expectation of success that the preservative-free ketamine solution could withstand terminal sterilization.
• Elimination of toxic preservatives: The ongoing efforts to remove benzethonium chloride from ketamine products due to toxicity (as evidenced by NRx Pharmaceuticals' Citizen Petition and the general understanding of BZT's toxicity) would strongly motivate a POSA to find methods to produce sterile ketamine formulations without such preservatives. Terminal sterilization of a preservative-free formulation is a logical approach to achieving this goal.

Therefore, a POSA, aware of the benefits of ready-to-use formulations, the drawbacks of preservatives like benzethonium chloride, and the widespread practice and known methods of terminal sterilization for injectable drugs (including ketamine), would have found it obvious to terminally sterilize the preservative-free, ready-to-use ketamine solution described by Biomed in an infusion container. The stability of ketamine under heat sterilization conditions, as shown in the prior art, would provide a reasonable expectation of success.