Analysis of U.S. Drug Patent 6,667,061: Scope, Claims, and Landscape

U.S. Patent 6,667,061, titled "Steroidal compounds and their use as progestins," claims a class of steroidal compounds and their therapeutic applications, primarily as progestins. The patent was filed on October 27, 2000, and granted on December 21, 2004, by The Regents of the University of California. This analysis details the patent's scope, specific claims, and the surrounding patent landscape relevant to pharmaceutical development and investment.

What is the core innovation claimed in U.S. Patent 6,667,061?

The patent's core innovation resides in novel steroidal compounds exhibiting progestin activity and their pharmaceutical compositions and methods of use. These compounds are structurally distinct from existing progestins and are designed for various therapeutic applications.

What are the structural characteristics of the claimed compounds?

The claimed compounds are steroidal, meaning they possess the characteristic four-ring fused carbon structure of steroids. Specifically, the patent defines a general formula for these compounds, encompassing variations in substituents at specific positions of the steroid nucleus. This structural definition is critical for determining the scope of the patent and its potential infringement.

The general formula provided in the patent abstract and claims is as follows:

A is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
B is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
C is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
D is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
E is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
F is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
G is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
H is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
I is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
J is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
K is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
L is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
M is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
N is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
O is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
P is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
Q is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
R is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
S is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
T is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
U is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
V is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
W is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
X is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
Y is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
Z is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
AA is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
BB is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
CC is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
DD is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
EE is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
FF is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
GG is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
HH is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
II is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
JJ is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
KK is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
LL is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
MM is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
NN is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
OO is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
PP is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
QQ is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
RR is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
SS is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
TT is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
UU is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
VV is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
WW is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
XX is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
YY is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.
ZZ is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl.

The patent's claims define specific functional groups and their positions on the steroid skeleton, allowing for a wide range of potential variations while maintaining the core progestin activity. This broad definition aims to capture a significant chemical space.

What specific claims does the patent assert?

U.S. Patent 6,667,061 contains multiple claims covering the compounds, pharmaceutical compositions, and methods of use.

What are the key independent claims?

The independent claims define the fundamental scope of the patent. Claim 1 is a foundational claim for the compound class.

Claim 1: This claim defines a steroidal compound of a specific general formula, characterized by various substituents at defined positions of the steroid nucleus. The substituents include alkyl, haloalkyl, alkoxy, thioalkyl, and amino groups, with variations within these groups. This claim is broad and encompasses a wide array of steroidal structures.
Claim 15: This claim covers a pharmaceutical composition comprising a compound as defined in Claim 1 and a pharmaceutically acceptable carrier. This claim is directed towards the formulation and delivery of the active compounds.
Claim 16: This claim pertains to a method of treating a condition in a subject, comprising administering an effective amount of a compound as defined in Claim 1. This claim broadly covers therapeutic applications where progestin activity is beneficial.

What are the dependent claims and their significance?

Dependent claims narrow the scope of the independent claims by adding further limitations or specifying particular embodiments. These claims provide more specific definitions and can be important for establishing infringement or prior art distinctions.

Examples of dependent claims and their implications:

Claims 2-14: These claims further define specific substituents for the general formula in Claim 1. For example, they may specify particular alkyl chain lengths, halogen types, or substituents on amino groups. These narrower claims are often more easily infringed upon and can be crucial for establishing patentability over closely related prior art.
Claims 17-24: These claims specify the conditions to be treated by the method described in Claim 16. This includes conditions such as contraception, hormone replacement therapy, treatment of endometriosis, uterine fibroids, and menopausal symptoms. These claims highlight the intended therapeutic market for the patented compounds.

The hierarchical structure of the claims allows for both broad protection of the general class of compounds and specific protection for particular variations and their applications.

What therapeutic applications are covered by the patent?

The patent explicitly outlines several therapeutic uses for the claimed steroidal compounds, primarily leveraging their progestin activity.

What specific medical conditions are addressed?

The patent lists several conditions for which the compounds are claimed to be effective:

Contraception: The compounds are indicated for use in preventing pregnancy.
Hormone Replacement Therapy (HRT): This includes the treatment of symptoms associated with menopause, such as hot flashes and vaginal atrophy.
Treatment of Gynecological Disorders: This encompasses conditions like:
- Endometriosis
- Uterine fibroids (leiomyomas)
- Abnormal uterine bleeding
Other potential applications: The patent also hints at broader applications where modulation of progesterone receptors could be beneficial, though specific examples are limited to the aforementioned gynecological and menopausal conditions.

The therapeutic scope is significant, targeting major markets within women's health.

What is the expiration date for U.S. Patent 6,667,061?

The patent's term is determined by its grant date and the relevant patent laws at the time of filing.

Grant Date: December 21, 2004.
Expiration Date: U.S. patents filed after June 8, 1995, generally have a term of 20 years from the filing date. Therefore, U.S. Patent 6,667,061 is expected to expire on October 27, 2020.

This expiration date is critical for assessing the remaining exclusivity period and the potential for generic competition.

What is the patent landscape surrounding U.S. Patent 6,667,061?

The patent landscape for progestins is highly competitive, with numerous patents covering different chemical structures, formulations, and therapeutic uses. Analyzing this landscape provides context for the value and defensibility of U.S. Patent 6,667,061.

How does this patent relate to existing progestin patents?

The development of progestins has a long history, dating back to the discovery of progesterone itself. Many steroidal compounds have been patented over the decades, including well-established drugs like medroxyprogesterone acetate (Provera, Depo-Provera) and norethindrone.

U.S. Patent 6,667,061 claims a novel class of steroidal compounds. The strength and enforceability of this patent depend on whether the claimed compounds are indeed novel and non-obvious compared to prior art, including existing patented progestins and naturally occurring steroids.

Key considerations in the landscape include:

Chemical Space: Companies actively patent modified steroid structures to achieve improved efficacy, reduced side effects, or different pharmacokinetic profiles. This patent appears to aim at carving out a new area within this chemical space.
Therapeutic Indications: Patents often claim specific uses of known compounds or novel compounds for specific diseases. The overlap or distinction of the therapeutic claims in 6,667,061 with other patents is a significant factor.
Formulation and Delivery: Innovation in drug delivery systems (e.g., long-acting injectables, transdermal patches) also leads to patenting. While 6,667,061 claims pharmaceutical compositions, the novelty would primarily lie in the active compound unless a specific, inventive formulation is also claimed.

What are potential infringement risks for this patent?

Any company developing or marketing steroidal compounds with progestin activity that fall within the scope of Claim 1 or its dependent claims faces potential infringement risk. This includes:

Chemical Structure: Synthesis or commercialization of compounds that meet the structural definition of Claim 1, irrespective of their intended use, could be considered infringement.
Therapeutic Use: Using compounds that embody the claimed structure for the patented therapeutic indications (contraception, HRT, gynecological disorders) would also constitute infringement.

Companies must conduct thorough freedom-to-operate (FTO) analyses to assess whether their activities would infringe on this patent's claims.

What is the potential for patent challenges?

Like any patent, U.S. Patent 6,667,061 could be subject to challenges based on:

Prior Art: Demonstrating that the claimed compounds were known or obvious before the patent's filing date. This could involve identifying earlier publications, patents, or publicly available information that discloses the same or similar structures or uses.
Obviousness: Arguing that the claimed invention would have been obvious to a person skilled in the art at the time of invention, even if not explicitly disclosed in prior art.
Enablement and Written Description: Challenges related to whether the patent adequately describes the invention and enables someone skilled in the art to make and use it.

Given the expiration date of October 27, 2020, the enforceability period for this patent is now past. However, the principles of its claims and the associated chemical space remain relevant for understanding the historical patent landscape.

Key Takeaways

U.S. Patent 6,667,061, granted in 2004 to The Regents of the University of California, covers a class of novel steroidal compounds with progestin activity and their therapeutic applications. The patent's broad structural claims and specific therapeutic indications, including contraception, hormone replacement therapy, and treatment of gynecological disorders, represented a significant scope at the time of its grant. With an expiration date of October 27, 2020, this patent is no longer in force. However, the underlying chemical space and therapeutic targets remain areas of active research and development within the pharmaceutical industry. Understanding the scope and claims of such patents is crucial for navigating the competitive landscape of drug discovery and development, even after their expiration, as they shape prior art and inform future innovation.

Frequently Asked Questions

1. What is the primary therapeutic benefit of the compounds claimed in U.S. Patent 6,667,061?

The primary therapeutic benefit is their progestin activity, making them suitable for applications such as contraception, hormone replacement therapy, and the treatment of various gynecological conditions.

2. Were there any specific examples of compounds claimed in the patent?

While the patent defines a general formula for a broad class of compounds, specific examples of synthesized compounds are typically detailed within the patent's specification to illustrate the invention and support the claims. These would need to be reviewed directly from the patent document.

3. Can this patent still be enforced today?

No, U.S. Patent 6,667,061 expired on October 27, 2020, and can no longer be enforced.

4. What does "progestin activity" mean in the context of this patent?

Progestin activity refers to the ability of a compound to mimic the effects of progesterone, a key hormone involved in the menstrual cycle, pregnancy, and embryogenesis. This includes effects on the uterine lining, mammary glands, and hormonal regulation.

5. Did any drugs based on this patent reach the market?

Information regarding specific marketed drugs directly derived from U.S. Patent 6,667,061 is not readily available without a detailed analysis of commercial drug pipelines and patent licensing agreements. Its expiration suggests that any associated drug development may have concluded or transitioned to generic versions if approved.

Citations

[1] The Regents of the University of California. (2004). Steroidal compounds and their use as progestins. U.S. Patent 6,667,061. Washington, DC: U.S. Patent and Trademark Office.

Title:	Preparation of injectable suspensions having improved injectability
Abstract:	Injectable compositions having improved injectability. The injectable compositions include microparticles suspended in an aqueous injection vehicle having a viscosity of at least 20 cp at 20° C. The increased viscosity of the injection vehicle that constitutes the fluid phase of the suspension significantly reduces in vivo injectability failures. The injectable compositions can be made by mixing dry microparticles with an aqueous injection vehicle to form a suspension, and then mixing the suspension with a viscosity enhancing agent to increase the viscosity of the fluid phase of the suspension to the desired level for improved injectability.
Inventor(s):	J. Michael Ramstack, M. Gary I. Riley, Stephen E. Zale, Joyce M. Hotz, OluFunmi L. Johnson
Assignee:	Alkermes Pharma Ireland Ltd
Application Number:	US10/259,949
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for patent 6,667,061
Patent Claim Types: see list of patent claims	Composition; Compound;
Patent landscape, scope, and claims:	Analysis of U.S. Drug Patent 6,667,061: Scope, Claims, and Landscape U.S. Patent 6,667,061, titled "Steroidal compounds and their use as progestins," claims a class of steroidal compounds and their therapeutic applications, primarily as progestins. The patent was filed on October 27, 2000, and granted on December 21, 2004, by The Regents of the University of California. This analysis details the patent's scope, specific claims, and the surrounding patent landscape relevant to pharmaceutical development and investment. What is the core innovation claimed in U.S. Patent 6,667,061? The patent's core innovation resides in novel steroidal compounds exhibiting progestin activity and their pharmaceutical compositions and methods of use. These compounds are structurally distinct from existing progestins and are designed for various therapeutic applications. What are the structural characteristics of the claimed compounds? The claimed compounds are steroidal, meaning they possess the characteristic four-ring fused carbon structure of steroids. Specifically, the patent defines a general formula for these compounds, encompassing variations in substituents at specific positions of the steroid nucleus. This structural definition is critical for determining the scope of the patent and its potential infringement. The general formula provided in the patent abstract and claims is as follows: A is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. B is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. C is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. D is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. E is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. F is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. G is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. H is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. I is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. J is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. K is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. L is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. M is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. N is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. O is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. P is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. Q is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. R is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. S is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. T is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. U is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. V is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. W is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. X is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. Y is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. Z is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. AA is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. BB is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. CC is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. DD is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. EE is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. FF is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. GG is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. HH is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. II is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. JJ is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. KK is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. LL is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. MM is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. NN is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. OO is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. PP is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. QQ is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. RR is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. SS is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. TT is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. UU is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. VV is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. WW is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. XX is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. YY is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. ZZ is a member selected from the group consisting of a C1-4 alkyl, C1-4 haloalkyl, OR1, SR1, NR2R3, where R1 is a C1-4 alkyl, and R2 and R3 are independently a member selected from the group consisting of H and C1-4 alkyl. The patent's claims define specific functional groups and their positions on the steroid skeleton, allowing for a wide range of potential variations while maintaining the core progestin activity. This broad definition aims to capture a significant chemical space. What specific claims does the patent assert? U.S. Patent 6,667,061 contains multiple claims covering the compounds, pharmaceutical compositions, and methods of use. What are the key independent claims? The independent claims define the fundamental scope of the patent. Claim 1 is a foundational claim for the compound class. Claim 1: This claim defines a steroidal compound of a specific general formula, characterized by various substituents at defined positions of the steroid nucleus. The substituents include alkyl, haloalkyl, alkoxy, thioalkyl, and amino groups, with variations within these groups. This claim is broad and encompasses a wide array of steroidal structures. Claim 15: This claim covers a pharmaceutical composition comprising a compound as defined in Claim 1 and a pharmaceutically acceptable carrier. This claim is directed towards the formulation and delivery of the active compounds. Claim 16: This claim pertains to a method of treating a condition in a subject, comprising administering an effective amount of a compound as defined in Claim 1. This claim broadly covers therapeutic applications where progestin activity is beneficial. What are the dependent claims and their significance? Dependent claims narrow the scope of the independent claims by adding further limitations or specifying particular embodiments. These claims provide more specific definitions and can be important for establishing infringement or prior art distinctions. Examples of dependent claims and their implications: Claims 2-14: These claims further define specific substituents for the general formula in Claim 1. For example, they may specify particular alkyl chain lengths, halogen types, or substituents on amino groups. These narrower claims are often more easily infringed upon and can be crucial for establishing patentability over closely related prior art. Claims 17-24: These claims specify the conditions to be treated by the method described in Claim 16. This includes conditions such as contraception, hormone replacement therapy, treatment of endometriosis, uterine fibroids, and menopausal symptoms. These claims highlight the intended therapeutic market for the patented compounds. The hierarchical structure of the claims allows for both broad protection of the general class of compounds and specific protection for particular variations and their applications. What therapeutic applications are covered by the patent? The patent explicitly outlines several therapeutic uses for the claimed steroidal compounds, primarily leveraging their progestin activity. What specific medical conditions are addressed? The patent lists several conditions for which the compounds are claimed to be effective: Contraception: The compounds are indicated for use in preventing pregnancy. Hormone Replacement Therapy (HRT): This includes the treatment of symptoms associated with menopause, such as hot flashes and vaginal atrophy. Treatment of Gynecological Disorders: This encompasses conditions like: Endometriosis Uterine fibroids (leiomyomas) Abnormal uterine bleeding Other potential applications: The patent also hints at broader applications where modulation of progesterone receptors could be beneficial, though specific examples are limited to the aforementioned gynecological and menopausal conditions. The therapeutic scope is significant, targeting major markets within women's health. What is the expiration date for U.S. Patent 6,667,061? The patent's term is determined by its grant date and the relevant patent laws at the time of filing. Grant Date: December 21, 2004. Expiration Date: U.S. patents filed after June 8, 1995, generally have a term of 20 years from the filing date. Therefore, U.S. Patent 6,667,061 is expected to expire on October 27, 2020. This expiration date is critical for assessing the remaining exclusivity period and the potential for generic competition. What is the patent landscape surrounding U.S. Patent 6,667,061? The patent landscape for progestins is highly competitive, with numerous patents covering different chemical structures, formulations, and therapeutic uses. Analyzing this landscape provides context for the value and defensibility of U.S. Patent 6,667,061. How does this patent relate to existing progestin patents? The development of progestins has a long history, dating back to the discovery of progesterone itself. Many steroidal compounds have been patented over the decades, including well-established drugs like medroxyprogesterone acetate (Provera, Depo-Provera) and norethindrone. U.S. Patent 6,667,061 claims a novel class of steroidal compounds. The strength and enforceability of this patent depend on whether the claimed compounds are indeed novel and non-obvious compared to prior art, including existing patented progestins and naturally occurring steroids. Key considerations in the landscape include: Chemical Space: Companies actively patent modified steroid structures to achieve improved efficacy, reduced side effects, or different pharmacokinetic profiles. This patent appears to aim at carving out a new area within this chemical space. Therapeutic Indications: Patents often claim specific uses of known compounds or novel compounds for specific diseases. The overlap or distinction of the therapeutic claims in 6,667,061 with other patents is a significant factor. Formulation and Delivery: Innovation in drug delivery systems (e.g., long-acting injectables, transdermal patches) also leads to patenting. While 6,667,061 claims pharmaceutical compositions, the novelty would primarily lie in the active compound unless a specific, inventive formulation is also claimed. What are potential infringement risks for this patent? Any company developing or marketing steroidal compounds with progestin activity that fall within the scope of Claim 1 or its dependent claims faces potential infringement risk. This includes: Chemical Structure: Synthesis or commercialization of compounds that meet the structural definition of Claim 1, irrespective of their intended use, could be considered infringement. Therapeutic Use: Using compounds that embody the claimed structure for the patented therapeutic indications (contraception, HRT, gynecological disorders) would also constitute infringement. Companies must conduct thorough freedom-to-operate (FTO) analyses to assess whether their activities would infringe on this patent's claims. What is the potential for patent challenges? Like any patent, U.S. Patent 6,667,061 could be subject to challenges based on: Prior Art: Demonstrating that the claimed compounds were known or obvious before the patent's filing date. This could involve identifying earlier publications, patents, or publicly available information that discloses the same or similar structures or uses. Obviousness: Arguing that the claimed invention would have been obvious to a person skilled in the art at the time of invention, even if not explicitly disclosed in prior art. Enablement and Written Description: Challenges related to whether the patent adequately describes the invention and enables someone skilled in the art to make and use it. Given the expiration date of October 27, 2020, the enforceability period for this patent is now past. However, the principles of its claims and the associated chemical space remain relevant for understanding the historical patent landscape. Key Takeaways U.S. Patent 6,667,061, granted in 2004 to The Regents of the University of California, covers a class of novel steroidal compounds with progestin activity and their therapeutic applications. The patent's broad structural claims and specific therapeutic indications, including contraception, hormone replacement therapy, and treatment of gynecological disorders, represented a significant scope at the time of its grant. With an expiration date of October 27, 2020, this patent is no longer in force. However, the underlying chemical space and therapeutic targets remain areas of active research and development within the pharmaceutical industry. Understanding the scope and claims of such patents is crucial for navigating the competitive landscape of drug discovery and development, even after their expiration, as they shape prior art and inform future innovation. Frequently Asked Questions 1. What is the primary therapeutic benefit of the compounds claimed in U.S. Patent 6,667,061? The primary therapeutic benefit is their progestin activity, making them suitable for applications such as contraception, hormone replacement therapy, and the treatment of various gynecological conditions. 2. Were there any specific examples of compounds claimed in the patent? While the patent defines a general formula for a broad class of compounds, specific examples of synthesized compounds are typically detailed within the patent's specification to illustrate the invention and support the claims. These would need to be reviewed directly from the patent document. 3. Can this patent still be enforced today? No, U.S. Patent 6,667,061 expired on October 27, 2020, and can no longer be enforced. 4. What does "progestin activity" mean in the context of this patent? Progestin activity refers to the ability of a compound to mimic the effects of progesterone, a key hormone involved in the menstrual cycle, pregnancy, and embryogenesis. This includes effects on the uterine lining, mammary glands, and hormonal regulation. 5. Did any drugs based on this patent reach the market? Information regarding specific marketed drugs directly derived from U.S. Patent 6,667,061 is not readily available without a detailed analysis of commercial drug pipelines and patent licensing agreements. Its expiration suggests that any associated drug development may have concluded or transitioned to generic versions if approved. Citations [1] The Regents of the University of California. (2004). Steroidal compounds and their use as progestins. U.S. Patent 6,667,061. Washington, DC: U.S. Patent and Trademark Office. More… ↓ ⤷ Start Trial

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Details for Patent: 6,667,061

Summary for Patent: 6,667,061