List of Excipients in Branded Drug CRINONE

Company	Tradename	Ingredient	NDC	Excipient	Potential Generic Entry
Allergan Inc	CRINONE	progesterone	0023-6150	CARBOMER HOMOPOLYMER TYPE B
Allergan Inc	CRINONE	progesterone	0023-6150	GLYCERIN
Allergan Inc	CRINONE	progesterone	0023-6150	HYDROGENATED PALM OIL
Allergan Inc	CRINONE	progesterone	0023-6150	LIGHT MINERAL OIL
Allergan Inc	CRINONE	progesterone	0023-6150	POLYCARBOPHIL
Allergan Inc	CRINONE	progesterone	0023-6150	SODIUM HYDROXIDE
Allergan Inc	CRINONE	progesterone	0023-6150	SORBIC ACID

CRINONE Excipient Strategy and Commercial Opportunities: Formulation, Patent, Generic, and Market Analysis

Last updated: September 4, 2026

Crinone is a progesterone vaginal gel containing 4% or 8% progesterone in a bioadhesive vehicle. Its commercial differentiation depends less on the progesterone molecule, which is long generic, than on the excipient system, vaginal residence time, dose delivery, applicator design, manufacturing consistency, and regulatory pathway. The strongest commercial opportunities are in excipient-controlled product performance, lower-cost single-dose delivery systems, fertility-clinic distribution, and alternative progesterone formulations.

What is Crinone and how does its formulation work?

Crinone is a vaginal progesterone gel approved in the United States for progesterone supplementation or replacement in women undergoing infertility treatment and for secondary amenorrhea, depending on strength and labeling. The 8% product delivers 90 mg of progesterone per prefilled applicator. The 4% product delivers 45 mg per applicator.[1]

Crinone formulation profile

Attribute	Crinone 4%	Crinone 8%
Active ingredient	Progesterone	Progesterone
Dose per applicator	45 mg	90 mg
Dosage form	Vaginal gel	Vaginal gel
Delivery system	Single-use prefilled applicator	Single-use prefilled applicator
Route	Vaginal	Vaginal
Principal formulation function	Bioadhesive local delivery	Bioadhesive local delivery
Primary clinical market	Progesterone supplementation	Progesterone supplementation and assisted reproduction
Original U.S. approval	1990s	1990s

The product uses a bioadhesive gel designed to remain in contact with vaginal tissue after administration. The labeled inactive ingredients include glycerin, mineral oil, polycarbophil, carbomer 934P, hydrogenated palm glycerides, and related formulation components depending on the marketed presentation and labeling version.[1]

The excipient system performs several functions:

1. It suspends or distributes progesterone in the gel.
2. It increases vaginal residence time.
3. It controls gel structure and extrusion.
4. It supports dose uniformity through the single-use applicator.
5. It influences patient acceptability, leakage, residue, and administration frequency.

What excipients are used in Crinone?

Crinone's commercial formulation is built around a mucoadhesive polymer and a semisolid vehicle rather than a conventional aqueous solution.

Polycarbophil and carbomer polymers

Polycarbophil and carbomer 934P are cross-linked acrylic acid polymers. In vaginal formulations, these polymers can swell in the presence of fluid and interact with mucosal surfaces. Their concentration, neutralization level, particle size, and hydration state affect:

• Viscosity
• Yield stress
• Adhesion to vaginal mucosa
• Spreadability
• Drug release
• Residence time
• Applicator extrusion force

These parameters create potential formulation differentiation. A competitor that uses the same active ingredient but a materially different polymer network may produce a different in vitro release profile, vaginal retention profile, or patient experience.

Glycerin

Glycerin functions primarily as a humectant and vehicle component. It can affect osmolarity, water activity, viscosity, and local tolerability. A formulation with excessive glycerin may increase osmotic stress or discomfort, while insufficient glycerin may reduce physical stability or alter gel texture.

Mineral oil and hydrogenated palm glycerides

The lipid components support the semisolid character of the product and influence progesterone dispersion. Because progesterone is poorly water-soluble, the oil phase is relevant to content uniformity, release, and physical stability.

Potential development concerns include:

• Phase separation
• Crystal growth of progesterone
• Changes in particle size
• Interaction between lipid excipients and polymeric thickeners
• Container or applicator compatibility
• Residual product and leakage after administration

What formulation patents protect Crinone?

The original formulation platform was associated with vaginal bioadhesive progesterone delivery and was protected by historical U.S. and international patent filings. Those early patents generally focused on combinations of progesterone, bioadhesive polymers, gel vehicles, and vaginal delivery systems rather than on progesterone itself.

Historical patent protection

Protection category	Commercial relevance
Progesterone vaginal gel composition	Covered the active ingredient combined with polymeric and vehicle components
Bioadhesive vaginal delivery	Addressed retention at the administration site
Controlled or sustained release	Related to progesterone release from a gel matrix
Single-dose applicator	Addressed delivery convenience and dose administration
Manufacturing and filling	Could protect uniformity, filling, and product handling

Historical Crinone-related patents have generally reached their ordinary patent terms or are no longer the principal barrier to generic entry. The key issue is therefore whether any later patents, listed patents, regulatory exclusivities, or product-specific obstacles remain relevant in the target jurisdiction.

A patent search should distinguish among:

• Patents assigned to Columbia Laboratories or affiliated entities
• Patents later assigned or licensed to Watson Pharmaceuticals, Actavis, Allergan, or other commercial parties
• U.S. patents listed in the FDA Orange Book
• Unlisted formulation, process, device, or foreign patents
• Patents covering a specific strength, use, or dosing regimen

What is the Orange Book status of Crinone?

The FDA Orange Book is the controlling source for listed patents and exclusivity associated with approved small-molecule products in the United States.[2] Crinone's active ingredient, progesterone, has no meaningful molecule-level exclusivity remaining. Any current patent barrier would need to arise from a listed formulation, method-of-use, delivery-system, or other product-specific patent.

For commercial diligence, the relevant Orange Book review should include:

• NDA 020701 and any related applications
• Listed patent numbers and use codes
• Patent delisting history
• Expiration dates
• Pediatric exclusivity
• Regulatory exclusivity
• Therapeutic-equivalence evaluations
• Approved dosage forms and strengths

An Orange Book listing does not prove that a patent is valid or infringed. It does establish the procedural framework for an abbreviated new drug application, including potential Paragraph IV litigation.

When does Crinone lose exclusivity?

Crinone has already lost the exclusivity associated with the progesterone molecule. The current commercial question is whether a generic or authorized-generic entrant can obtain approval and achieve substitutable or commercially acceptable status.

Exclusivity timeline

Event	Timing
Progesterone chemical exclusivity	Expired
Original Crinone U.S. approval	1990s
Early formulation patent term	Generally expired or near expiration depending on patent and adjustment
Current market barrier	Formulation equivalence, regulatory approval, manufacturing, and distribution
Generic launch timing	Depends on ANDA approval, patent certifications, and commercial strategy

Crinone does not have biologic exclusivity because progesterone is a synthetic small molecule. Biosimilar risk is therefore not applicable. Competitive pressure would come from generic vaginal gels, vaginal inserts, suppositories, capsules, injections, and compounded products.

What Paragraph IV challenges affect Crinone?

A Paragraph IV challenge would require an ANDA applicant to certify that a listed patent is invalid, unenforceable, or not infringed. The commercial impact depends on whether the reference product has active Orange Book patents and whether the applicant seeks approval for the same strength, route, indication, and delivery system.

Potential ANDA strategies include:

1. A direct copy of the 4% or 8% gel.
2. A formulation with a different excipient system.
3. A product that avoids a listed method-of-use patent.
4. A product supported by a different release or equivalence approach.
5. A product launched after patent expiration without Paragraph IV risk.

For a semisolid vaginal product, the regulatory burden may be higher than for a conventional oral tablet. The applicant may need to establish pharmaceutical equivalence, bioequivalence, product quality, microbial controls, rheological comparability, and device performance. The exact FDA pathway depends on the approved reference product and the agency's product-specific guidance.

What generic entry risks exist for Crinone?

Generic competition is technically feasible but commercially uneven.

Main generic entry barriers

Barrier	Effect on entrants
Semisolid formulation	Requires control of rheology, homogeneity, and release
Vaginal delivery	Creates local tolerability and retention issues
Prefilled applicator	Adds device, filling, and dose-delivery requirements
Progesterone dispersion	Raises content-uniformity and crystallization risks
Clinical substitution	May depend on therapeutic-equivalence designation
Limited market size	Can reduce attractiveness to large generic companies
Fertility-clinic purchasing	May require specialized sales and distribution
Manufacturing scale	Small-volume production may carry high unit costs

The largest practical risk to a generic entrant is not the cost of progesterone. It is the ability to produce a stable, uniform gel in a single-use applicator while matching the reference product's administration characteristics and regulatory requirements.

How strong is the Crinone patent estate?

The original patent estate was commercially meaningful because it combined:

• A known active ingredient with a site-specific delivery route
• Bioadhesive polymer technology
• A vaginal gel vehicle
• A prefilled applicator
• Use in assisted reproduction and hormone supplementation

Its present strength is lower because the principal patent terms have aged and progesterone is widely available. The strongest remaining protection, where present, would likely be narrow and product-specific.

Patent-strength assessment

Patent category	Current strategic strength
Progesterone composition of matter	Very weak; expired
Broad vaginal progesterone use	Weak to moderate, depending on claim and jurisdiction
Specific polymer combination	Moderate if unexpired and claim scope is enforceable
Applicator configuration	Moderate if separately protected
Manufacturing process	Moderate where difficult to design around
Specific formulation parameters	Potentially strong if supported by comparative data
Trademark and brand recognition	Commercially relevant but not patent protection

A formulation patent is strongest when it claims a technically necessary combination that produces measurable advantages, such as improved retention, reduced leakage, controlled release, enhanced stability, or consistent dosing. Broad claims covering progesterone in a vaginal gel are more vulnerable to prior-art and obviousness challenges.

What excipient strategies create commercial opportunities?

The most attractive opportunities involve excipient systems that improve patient experience or simplify regulatory differentiation.

Lower-residue and reduced-leakage gels

Patients may discontinue vaginal products because of leakage, residue, or discomfort. A polymer system with optimized yield stress and rapid mucosal adhesion could reduce the amount of gel expelled after administration.

Commercial value would depend on measurable improvements in:

• Retention time
• Leakage volume
• Patient-reported residue
• Administration frequency
• Applicator usability

Preservative-free formulations

A preservative-free product can appeal to patients with irritation or sensitivity concerns. The development challenge is microbial control during manufacture, filling, storage, and use. Single-dose packaging is advantageous because it limits repeated container access.

Lower-osmolality vehicles

A lower-osmolality gel may improve tolerability in some users. Changes to glycerin and other water-soluble excipients must be balanced against viscosity, product stability, and vaginal retention.

Alternative bioadhesive polymers

Potential alternatives include modified cellulose polymers, polycarbophil derivatives, carbomer grades, hyaluronic-acid systems, and other mucoadhesive materials. Each creates a different regulatory and patent profile.

A new polymer system may support:

• New formulation patents
• Improved release characteristics
• Reduced leakage
• Different dosing frequency
• Better compatibility with progesterone particle size
• A differentiated patient-experience claim

Biodegradable or low-residue delivery systems

A gel that forms a thin mucoadhesive film and then clears more rapidly may reduce patient complaints. The commercial opportunity is strongest if the product maintains adequate progesterone exposure without increasing dosing frequency.

Ready-to-use applicator improvements

The applicator is a major product-development opportunity. Improvements may include:

• Lower extrusion force
• Better dose accuracy
• Reduced residual volume
• Smaller package size
• Easier administration
• More sustainable materials
• Better compatibility with automated filling

An applicator change can create a combination-product or device-related regulatory workstream. It can also create design-patent, utility-patent, and trade-secret protection.

How does Crinone compare with competing progesterone products?

Product category	Key advantage	Key limitation
Crinone vaginal gel	Bioadhesive delivery and prefilled dosing	Residue, leakage, and formulation complexity
Vaginal progesterone inserts	Familiar vaginal route and solid dosage form	Handling, melting, and residue
Progesterone capsules used vaginally	Broad availability and low cost	Off-label use and variable administration
Intramuscular progesterone	Established systemic exposure	Injection burden and pain
Subcutaneous progesterone	Alternative injectable route	Injection-site issues and device requirements
Compounded progesterone	Customization and access	Variable quality and limited substitution
Oral progesterone	Convenient systemic administration	Sedation, metabolism, and differing exposure

Crinone's competitive position depends on adherence, tolerability, reimbursement, and fertility-clinic protocols rather than on active-ingredient exclusivity.

What licensing and partnership opportunities exist?

Commercial opportunities may arise through licensing of:

• Mucoadhesive polymer technology
• Vaginal drug-delivery platforms
• Prefilled applicators
• Low-residue gel systems
• Progesterone particle engineering
• Contract manufacturing of sterile or controlled vaginal products
• Regional rights for generic or branded versions

A partner with an existing fertility portfolio can reduce customer-acquisition costs. A formulation company may instead license the excipient platform to a generic manufacturer and retain rights to follow-on products.

The most defensible deal structure would tie royalties to measurable product differentiation, such as an approved formulation patent, a granted device patent, a new dosing schedule, or a demonstrated improvement in retention or tolerability.

What regulatory status and manufacturing issues matter?

FDA approval of a Crinone competitor would require more than matching progesterone concentration. Manufacturing controls should address:

• Identity and assay of progesterone
• Particle-size distribution
• Homogeneity during filling
• Rheology and viscosity
• Microbial limits
• Container-closure integrity
• Applicator dose accuracy
• Stability under labeled storage
• In-use performance
• Product-contact extractables and leachables

The manufacturing process is a potential barrier because progesterone dispersion and polymer hydration can be sensitive to mixing order, shear, temperature, hydration time, and deaeration. These variables can become trade secrets even when the final excipient list is public.

What is the commercial outlook for Crinone-related products?

The addressable market is specialized but durable. Fertility treatment creates recurring demand, while progesterone supplementation has multiple competing routes and products. Revenue exposure is most sensitive to:

• Assisted-reproduction procedure volumes
• Insurance coverage
• Fertility-clinic protocols
• Generic vaginal-product entry
• Product shortages
• Patient adherence
• Pricing relative to inserts and compounded products

A branded reformulation would need a clear benefit to justify premium pricing. A generic strategy can succeed with lower manufacturing cost, reliable supply, and equivalent therapeutic performance. An excipient platform can generate greater value if it supports multiple vaginal products rather than a single progesterone product.

Key Takeaways

• Crinone's main differentiation comes from its bioadhesive vaginal gel and prefilled applicator, not from progesterone exclusivity.
• Polycarbophil, carbomer, glycerin, mineral components, and lipid excipients jointly control residence time, release, viscosity, and patient experience.
• Historical broad formulation patents have limited current blocking power because progesterone and early patent terms are old.
• The principal generic barriers are semisolid formulation control, applicator manufacturing, equivalence requirements, and market size.
• The strongest follow-on opportunities involve lower leakage, lower residue, preservative-free delivery, improved applicators, and alternative mucoadhesive polymers.
• Biosimilar competition is irrelevant because Crinone is a small-molecule product.
• A commercially valuable new patent would need to claim a specific excipient combination, measurable performance advantage, delivery system, or manufacturing process.
• Fertility-clinic partnerships, regional licensing, and platform licensing are more attractive than broad molecule-level exclusivity strategies.

FAQs

Can a generic use different excipients from Crinone?

Yes. A generic may use different inactive ingredients if it meets applicable FDA requirements for pharmaceutical equivalence, bioequivalence, product quality, safety, and performance.

Is progesterone in Crinone still patent protected?

Progesterone itself is not meaningfully protected by composition-of-matter exclusivity. Any relevant protection would arise from specific formulation, use, device, or manufacturing claims.

Is Crinone a biologic subject to biosimilar competition?

No. Crinone contains progesterone, a small-molecule active ingredient. Competition would come through generic or other pharmaceutical pathways.

Which excipient is most important to Crinone's performance?

The cross-linked polymer system is central because it affects adhesion, viscosity, retention, release, and leakage. Its performance depends on the complete formulation and manufacturing process, not on one excipient in isolation.

Could a lower-dose Crinone formulation create new commercial value?

Potentially. A lower-dose product could target improved tolerability, reduced residue, or lower cost, but it would require regulatory support for the new strength, dosing regimen, and clinical use.

References

1. U.S. Food and Drug Administration. (n.d.). Crinone (progesterone) vaginal gel prescribing information. FDA.
2. U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations: Orange Book. FDA.
3. U.S. Food and Drug Administration. (n.d.). Abbreviated new drug application submissions: Generic drug development guidance. FDA.
4. U.S. Pharmacopeia. (2024). United States Pharmacopeia and National Formulary. U.S. Pharmacopeial Convention.
5. U.S. Patent and Trademark Office. (n.d.). Patent Center and Patent Public Search. USPTO.