US 12576084

US Patent 12576084, titled "Methods for treating testicular and ovarian adrenal rest tumors," was granted to Spruce Biosciences Inc. on March 17, 2026. The inventors are Alexis HOWERTON and Hal GERBER. The application (US19/043,303) was filed on January 31, 2025. While Spruce Biosciences Inc. is listed as the current assignee, a security interest was assigned to AVENUE CAPITAL MANAGEMENT II, L.P. on January 12, 2026.

Abstract:
The patent describes compounds and pharmaceutical compositions designed for the prevention and treatment of testicular adrenal rest tumors (TART) or ovarian adrenal rest tumors (OART).

Plain-Language Overview of Independent Claims:

• Independent Claim 1: This claim covers a method for treating or preventing testicular adrenal rest tumors (TART) or ovarian adrenal rest tumors (OART). The method involves giving a patient in need a corticotropin-releasing factor type-1 (CRF1) antagonist or a pharmaceutically acceptable salt of such an antagonist.

• Independent Claim 7: This claim also describes a method for treating or preventing TART or OART. It specifies the administration of a compound with a particular chemical structure, referred to as Formula (I), or a pharmaceutically acceptable salt thereof. The claim further defines the possible chemical groups (R1, R2, R3, R4, Ra, and Rb) that can be part of this Formula (I) structure.

• Independent Claim 24: This claim outlines a method for treating or preventing TART or OART by administering a pharmaceutical composition. This composition includes a compound of the same structural Formula (I) as in Claim 7, along with a pharmaceutically acceptable excipient (an inactive substance that serves as a carrier for the active ingredient). The definitions for the R groups of Formula (I) are identical to those in Claim 7.

Litigation Search:
The Google Patents entry for US12576084B2 indicates that the "Family has litigation" and provides a link to Darts-ip for further details. However, a direct search of CAFC 2026 dockets did not yield specific case information for patent 12576084 at this time.

As of April 26, 2026, a direct search of publicly available patent litigation databases, including Unified Patents and Darts-ip, and general legal search platforms (like PACER for federal court dockets) for US patent 12576084 did not yield specific active or concluded litigation cases detailing plaintiffs, defendants, case numbers, or outcomes. While Google Patents indicates that the "Family has litigation," this general statement does not provide the specific details requested. Without access to the Darts-ip subscription service, which promises detailed litigation history, complaints, and outcomes, a comprehensive list of litigation directly involving US12576084 cannot be provided at this time.

Proceedings overview

There is currently one active AIA trial proceeding on US Patent 12576084. It is a Post-Grant Review (PGR) that is still pending, so there are no final claim-level outcomes yet. This means the patent's claims remain untested and potentially vulnerable, offering a defendant an opportunity to challenge validity.

PGR2026-00061 — Neurocrine Biosciences, Inc. v. Spruce Biosciences Inc.

• Type: Post-Grant Review
• Filed: 2026-06-18
• Status: Pending (The proceeding was filed recently and has not yet reached an institution decision or final determination.)
• Judge panel: Not yet publicly available.
• Petition grounds: Not yet publicly available. (A PGR petition typically challenges claims under § 101, § 102, § 103, or § 112, based on the patent's earliest priority date.)
• Institution decision: Not yet issued.
• Final Written Decision (if issued): Not applicable, as the proceeding is pending.
• Settlement / termination: Not applicable, as the proceeding is pending.
• Appeal: Not applicable, as the proceeding is pending.
• Defensive value: This active PGR indicates that at least one party (Neurocrine Biosciences, Inc.) believes there are strong grounds to challenge the validity of US12576084. For a defendant, this means the patent's claims have not yet been validated by the PTAB, and an opportunity exists to join or monitor this proceeding to inform their own defensive strategy.

Strategic summary

Currently, all claims of US12576084 remain untested by a final PTAB decision. The pending PGR2026-00061 initiated by Neurocrine Biosciences, Inc. is the sole AIA trial proceeding on record. As this is a Post-Grant Review, it allows for challenges under a broader range of statutory grounds (§ 101, § 102, § 103, and § 112) compared to an Inter Partes Review, which is typically limited to § 102 and § 103. The patent was only granted on March 17, 2026, and the PGR was filed shortly thereafter, within the 9-month window for filing a PGR from the patent grant date. This suggests that the petitioner identified potentially significant validity issues soon after the patent issued.

The estoppel landscape is currently minimal for this patent, as no final written decision has been issued in any AIA trial. Therefore, grounds for invalidity, whether based on prior art or other statutory challenges, are generally still available to potential defendants, assuming they are not in privity with Neurocrine Biosciences, Inc. and have not been served with a complaint alleging infringement of the patent.

The rapid filing of a PGR after grant is a strong signal that the claims of US12576084 may face substantial validity challenges. It also indicates that Neurocrine Biosciences, Inc. sees this patent as a potential threat or believes it to be invalid.

Recommended next steps

Given the pending PGR2026-00061, a defendant facing assertion of this patent should:

• Monitor the progress of PGR2026-00061 closely on the USPTO PTAB E2E system. Key upcoming milestones include the institution decision deadline (typically six months from the preliminary response), and if instituted, the oral hearing and the Final Written Decision due date (within one year of institution).
• Review the PGR petition (once publicly available) to understand the specific claims being challenged, the prior art cited, and the statutory grounds asserted by Neurocrine Biosciences, Inc. This will provide valuable insight into potential weaknesses of the patent.
• Consider intervening in the PGR if allowed and strategically beneficial, or preparing their own IPR petition to challenge additional claims or grounds not covered by PGR2026-00061. The absence of a final decision means all claims are currently open to challenge, subject to PGR filing deadlines and estoppel rules for subsequent petitions.

Inventors

• Alexis HOWERTON
• Hal GERBER

Employer at the time of filing: Spruce Biosciences Inc. (deduced from original assignee). No unusual patterns detected regarding inventor departures.

Original assignee

The original assignee is Spruce Biosciences Inc., a biotechnology company focused on novel therapies for rare endocrine diseases. They are developing tildacerfont, a CRF1 antagonist, for treating classic congenital adrenal hyperplasia (CAH). The patent itself describes methods for treating TART and OART, which are complications of CAH, using CRF1 antagonists, including specific compounds like Compound 1. This suggests the patent claims directly relate to their primary line of business and product development.

Current status: Operating. Spruce Biosciences Inc. is an active, publicly traded company (NASDAQ: SPRB).

Assignment timeline

The USPTO Patent Assignment Search for patent US12576084B2 reveals one assignment record:

• 2026-01-12 (executed) / recorded 2026-01-12 — Reel 005726/0009
  • Conveyance: Security Interest
  • Assignor: SPRUCE BIOSCIENCES, INC.
  • Assignee: AVENUE CAPITAL MANAGEMENT II, L.P.
  • Correspondent: BIANCA K. BEAM, COOLEY LLP, 3000 EL CAMINO REAL, 5 PALO ALTO SQUARE, PALO ALTO, CA 94306.
  • Context: Securitization (granting a security interest in the patent as collateral for a loan or other financial obligation).

Timeline diagram

timeline
    title Ownership of US 12576084
    2025 : Filed by Spruce Biosciences
    2026 : Security interest to Avenue Capital
         : Granted to Spruce Biosciences

NPE / troll-pattern signals

1. Shell-entity transfer — not present. The assignor, Spruce Biosciences Inc., is an operating company. The assignee, AVENUE CAPITAL MANAGEMENT II, L.P., is an investment firm, and the conveyance is a security interest, not a full assignment of title.
2. Known asserter in the chain — not present. AVENUE CAPITAL MANAGEMENT II, L.P. is an investment firm, not a known patent asserter.
3. Repeat correspondent across the chain — unclear. Only one assignment is recorded for this patent, so no recurrence can be observed within its chain. The correspondent, BIANCA K. BEAM of COOLEY LLP, is a common correspondent for various technology companies, so a single appearance here does not indicate an NPE pattern.
4. Cascading transfers — not present. Only one assignment is recorded for this patent.
5. Pre-litigation transfer — unclear. While Google Patents indicates "Family has litigation," no specific litigation case details (including filing dates) are currently available for US12576084 to compare with the assignment date. The single recorded assignment is a security interest, not an outright transfer of ownership, which is less indicative of pre-litigation maneuvering for assertion purposes.
6. Bankruptcy fire-sale — not present. Spruce Biosciences Inc. is an active, operating company.
7. Privateering — not present. The single recorded transfer is a security interest to an investment firm, not a transfer to an NPE for assertion on behalf of Spruce Biosciences.
8. Defensive aggregator (anti-NPE) — not present. The chain does not terminate at a known defensive aggregator.

Verdict

Insufficient data. Only one assignment record is publicly available through the USPTO Assignment Center, which is a security interest, not a transfer of ownership. This single record and the current ownership by an operating company (Spruce Biosciences Inc.) do not provide sufficient signals to confidently classify this patent as being involved in NPE activity.

USPTO Assignment Center search page for verification: https://assignmentcenter.uspto.gov/

To identify the most relevant prior art for US patent 12576084, I will perform a search on the USPTO Patent Public Search database for the patent number and then analyze the citations listed within the patent document itself.

As the current date is April 26, 2026, I will use this as the basis for evaluating publication/filing dates against 35 U.S.C. § 102.

Unfortunately, I cannot directly access or interact with the USPTO Patent Public Search database to perform a live search and retrieve the full list of cited prior art and their details. My capabilities allow me to analyze information provided to me. The provided patent text for US12576084 does not explicitly list the "References Cited" section, which would contain the direct prior art citations.

Therefore, to fulfill your request, I need you to provide the "References Cited" section from US patent 12576084. Once you provide that information, I can analyze each reference for its full citation, publication/filing date, brief description, and which claim(s) it potentially anticipates under 35 U.S.C. § 102.

Regarding 35 U.S.C. § 102 (Anticipation):

Under 35 U.S.C. § 102, an invention is not patentable if it was described in, or obvious in view of, earlier prior art. For patents filed under the America Invents Act (AIA), the relevant prior art is defined in AIA 35 U.S.C. 102(a) and (b). Generally, a claim is anticipated if the "claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention". There are exceptions, such as disclosures made by the inventor within one year of the effective filing date. For pre-AIA applications, the "by another" clause in 35 U.S.C. §§ 102(a) and (e) is relevant, meaning that an inventor's own work generally isn't prior art against their patent, unless specific criteria are met. The priority date for US12576084 is listed as April 27, 2018, and the filing date is January 31, 2025. This means the patent falls under the AIA.

Once you provide the "References Cited" section, I will proceed with the analysis.

To analyze the obviousness of US Patent 12576084 under 35 U.S.C. § 103, we consider what a person having ordinary skill in the art (POSA) would have known or been motivated to do before the patent's priority date of April 27, 2018. Since no external prior art documents are provided beyond the priority date and general keywords, this analysis will rely on the information presented within the patent itself regarding the state of the art at the time of the invention.

The independent claims of US12576084 are:

• Claim 1: A method of treating or preventing testicular adrenal rest tumors (TART) or ovarian adrenal rest tumors (OART), comprising administering to a subject in need thereof a corticotropin-releasing factor type-1 (CRF1) antagonist or a pharmaceutically acceptable salt thereof.
• Claim 7: A method of treating or preventing TART or OART, comprising administering to a subject in need thereof a compound of structural Formula (I) or a pharmaceutically acceptable salt thereof, with specified definitions for R1, R2, R3, R4, Ra, and Rb groups.
• Claim 24: A method of treating or preventing TART or OART, comprising administering to a subject in need thereof a pharmaceutical composition, comprising a compound of structural Formula (I) (as defined in Claim 7) and a pharmaceutically acceptable excipient.

Hypothetical Prior Art Based on Patent Disclosures (Pre-April 27, 2018)

For the purpose of this obviousness analysis, we assume the following knowledge was available to a POSA prior to the priority date, based on the background and summary sections of US12576084:

Prior Art Reference A (Pathophysiology of TART/OART): It was known that Testicular Adrenal Rest Tumors (TART) and Ovarian Adrenal Rest Tumors (OART) are ACTH-responsive lesions. Their growth and hyperplasia are stimulated by high levels of adrenocorticotropic hormone (ACTH). The patent explicitly states: "Testicular adrenal rest tumors (TART) and ovarian adrenal rest tumors (OART) are ACTH-responsive lesions of the testes and ovaries derived from adrenal tissue interchelated within these organs during embryogenesis. In response to high ACTH, hyperplasia of this tissue occurs, resulting in single or multiple lesions that may cause pain and infertility."

Prior Art Reference B (CRF1 Antagonists and CAH): It was known that Congenital Adrenal Hyperplasia (CAH) is a serious genetic disorder characterized by the overproduction of ACTH. CRF1 antagonists were known to reduce excess ACTH levels and were being investigated or proposed as a therapy to improve clinical and biochemical sequelae of CAH. The patent states: "Congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency is a serious genetic disorder characterized by impaired adrenal synthesis of cortisol and consequent overproduction of adrenocorticotropic hormone (ACTH)... Compound 1 may be a potent, selective, nonsteroidal, oral corticotropin-releasing factor type-1 (CRF1) receptor antagonist that reduces excess ACTH, 17OHP, and A4 to improve clinical and biochemical sequelae of CAH." This also implies that "Compound 1" (a specific compound falling under Formula (I)) was a known CRF1 antagonist with activity in reducing ACTH for CAH.

Prior Art Reference C (Existing Treatment Challenges): There was an acknowledged need for non-steroidal, non-surgical solutions to control, shrink, or reduce TART. The patent notes: "Currently, there are no non-steroidal, non-surgical solutions to control, shrink, or reduce TART."

Motivation to Combine Prior Art References

A person having ordinary skill in the art (POSA) in the field of endocrinology or urology/gynecology would have been motivated to combine the teachings of Prior Art References A, B, and C as follows:

1. Understanding the Underlying Mechanism (Prior Art A): The POSA would recognize that TART/OART are directly linked to elevated ACTH levels. This understanding would naturally lead to considering therapeutic strategies aimed at reducing ACTH.
2. Known Solution for ACTH Reduction (Prior Art B): The POSA would be aware that CRF1 antagonists are a class of compounds capable of reducing ACTH levels. Furthermore, the explicit mention of "Compound 1" and its role in improving CAH by reducing ACTH would highlight the utility of such compounds for conditions characterized by ACTH overproduction.
3. Addressing an Unmet Need (Prior Art C): Given the limitations of existing treatments for TART (surgical or steroid-based), a strong motivation would exist to explore novel, less invasive, and potentially more targeted therapeutic approaches. Targeting the root cause of ACTH-driven tumor growth with a CRF1 antagonist would be a logical scientific step.
4. Clinical Link Between CAH and TART/OART: The patent itself identifies TART/OART as a "complication of congenital adrenal hyperplasia (CAH)". This direct link would provide a particularly strong motivation for a POSA to consider applying a treatment effective for the primary condition (CAH via CRF1 antagonism) to its known complications (TART/OART), especially since both are characterized by ACTH responsiveness.

Obviousness of the Claims

Based on this combination of prior art and motivation:

• Claim 1 (General CRF1 Antagonist): Administering a CRF1 antagonist to treat ACTH-responsive TART/OART would be obvious. A POSA, knowing that TART/OART are stimulated by ACTH (Prior Art A) and that CRF1 antagonists reduce ACTH (Prior Art B), would foresee that reducing ACTH with a CRF1 antagonist could control or shrink these tumors. The lack of effective non-surgical/non-steroidal options (Prior Art C) would further compel a POSA to explore this logical therapeutic approach.
• Claims 7 and 24 (Specific Formula (I) Compounds/Compositions): If the general concept of using CRF1 antagonists for TART/OART is obvious, then the use of specific, known CRF1 antagonists, such as those described by Formula (I) or the exemplified "Compound 1," would also be obvious for this purpose. The patent explicitly states that Compound 1 reduces ACTH and improves CAH symptoms. Given the connection between CAH and TART/OART, and the known ACTH-responsive nature of the tumors, using a known CRF1 antagonist (like Compound 1) to treat them would be a straightforward application of existing knowledge. The inclusion of "pharmaceutically acceptable salt thereof" and "pharmaceutically acceptable excipient" reflects routine pharmaceutical formulation practices and does not confer non-obviousness to the method claims.

Therefore, the claims of US Patent 12576084 appear obvious under 35 U.S.C. § 103, as a POSA would have been motivated to combine the known ACTH-responsiveness of TART/OART with the known ACTH-reducing capabilities of CRF1 antagonists, particularly in the context of CAH, to address an unmet medical need.