List of Excipients in Branded Drug URSO 250

Company	Tradename	Ingredient	NDC	Excipient	Potential Generic Entry
Allergan Inc	URSO 250	ursodiol	58914-785	CARNAUBA WAX
Allergan Inc	URSO 250	ursodiol	58914-785	CELLULOSE, MICROCRYSTALLINE
Allergan Inc	URSO 250	ursodiol	58914-785	CETYL ALCOHOL
Allergan Inc	URSO 250	ursodiol	58914-785	DIBUTYL SEBACATE

URSO 250 Excipient Strategy and Commercial Opportunities

Last updated: August 16, 2026

URSO 250 is a 250 mg ursodiol tablet used for primary biliary cholangitis and dissolution of radiolucent cholesterol gallstones. Its commercial position is mature: the active ingredient is off-patent, generic ursodiol is available, and product differentiation depends more on excipient performance, manufacturing economics, dose convenience, supply reliability, and regulatory execution than on exclusivity.

The most credible opportunities are lower-cost tablet manufacture, improved dissolution and dose uniformity, reduced pill burden through higher-strength or modified presentations, and differentiated formulations for patients with swallowing, gastrointestinal, or adherence problems.

What is URSO 250 and how is it used?

URSO 250 contains 250 mg of ursodiol, also known as ursodeoxycholic acid. It is an oral, film-coated tablet.

FDA-approved uses and dosing

The FDA label identifies two principal uses:

Indication	Labeled dosing context
Primary biliary cholangitis	Approximately 13 to 15 mg/kg/day, administered in two to four divided doses
Radiolucent gallstones	Approximately 8 to 10 mg/kg/day, usually divided into two or three doses

The dose range creates a substantial tablet burden for many patients. A 70 kg patient treated for primary biliary cholangitis may require approximately 910 to 1,050 mg daily, equivalent to four 250 mg tablets or a combination of 250 mg and 500 mg tablets. The FDA-approved URSO Forte 500 mg presentation addresses some of this burden.[1]

Ursodiol is poorly soluble in water. Formulation performance depends on particle size, wetting, disintegration, excipient selection, compression force, and dissolution conditions. These properties are central to generic equivalence and to any attempt to create a differentiated product.

What excipients are used in URSO 250?

The URSO 250 labeling identifies a conventional tablet excipient system. Public labeling has identified the following excipients for the product or its tablet system:

• Carnauba wax
• Colloidal silicon dioxide
• Crospovidone
• Magnesium stearate
• Microcrystalline cellulose
• Povidone
• Sodium starch glycolate
• Talc
• Titanium dioxide

The exact composition and supplier grades should be confirmed against the current FDA-approved label and the manufacturer’s controlled product documentation before use in a regulatory or freedom-to-operate analysis.[1]

Functional role of the excipients

Excipient	Primary formulation role	Commercial relevance
Microcrystalline cellulose	Diluent and dry-compression aid	Supports tablet hardness and manufacturability
Crospovidone	Superdisintegrant	Can improve tablet breakup and dissolution
Sodium starch glycolate	Superdisintegrant	Provides swelling-driven disintegration
Povidone	Binder	Supports granule strength and content uniformity
Colloidal silicon dioxide	Glidant and moisture-management aid	Improves powder flow and manufacturing consistency
Magnesium stearate	Lubricant	Reduces ejection force, but excess levels can slow wetting
Talc	Processing and anti-adherence aid	Can influence flow, sticking, and coating behavior
Titanium dioxide	Opacifier and colorant	Supports appearance and light protection
Carnauba wax	Polishing or coating-related component	May affect surface finish and downstream processing

The formulation has the profile of a conventional immediate-release tablet. This reduces regulatory complexity compared with a controlled-release, gastroretentive, lipid-based, or nanoparticle product. It also limits differentiation unless a developer can demonstrate a meaningful clinical, adherence, manufacturing, or stability benefit.

What excipient strategies can improve URSO 250?

The strongest strategy depends on the commercial objective. A cost-focused generic should prioritize robust, widely qualified excipients. A differentiated product may justify more complex excipient technology if it reduces pill burden or solves a documented performance problem.

Strategy 1: Optimize conventional immediate-release tablets

A conventional formulation can be improved without changing the dosage form. Key development variables include:

• Ursodiol particle-size distribution
• Microcrystalline cellulose grade and compaction behavior
• Crospovidone versus sodium starch glycolate ratio
• Povidone level and granulation endpoint
• Magnesium stearate concentration and blending time
• Tablet porosity and compression force
• Coating weight and aqueous film-coating conditions

The principal technical risk is the interaction between lubrication and dissolution. Magnesium stearate is hydrophobic. Excessive concentration or prolonged blending can reduce wetting and delay dissolution. A formulation with adequate ejection performance but lower lubricant exposure may deliver a better dissolution profile.

A direct-compression process could reduce equipment, drying, and cycle-time costs. Wet granulation may provide better flow and content uniformity where ursodiol particle characteristics create segregation or poor compactability. The appropriate choice depends on the API’s bulk density, flow, particle-size distribution, and supplier consistency.

Strategy 2: Improve dissolution through particle engineering

Ursodiol’s limited aqueous solubility creates an opportunity for particle engineering. Relevant approaches include:

• Micronized ursodiol
• Co-milled API-excipient systems
• Spray-dried dispersions
• Amorphous solid dispersions
• Wetting-agent systems
• Lipid-based formulations
• Cyclodextrin complexes
• Nanocrystalline suspensions

For a standard tablet, micronization and improved wetting are more commercially practical than a complex amorphous dispersion. They can preserve the established oral route while targeting faster dissolution and potentially lower variability.

The regulatory burden rises with formulation complexity. A novel dispersion or lipid system may require extensive stability, scale-up, extractables and leachables, bioequivalence, and process-control work. A generic tablet using conventional excipients is more likely to fit an established ANDA development path.

Strategy 3: Reduce pill burden

Pill burden is the clearest product-level opportunity. A 500 mg tablet can reduce the number of units required for patients receiving weight-based ursodiol therapy. Further opportunities include:

• A higher-strength tablet, subject to dose flexibility and tablet size
• A scored 500 mg tablet
• A 250 mg tablet with improved swallowability
• A combination pack containing 250 mg and 500 mg strengths
• A dispersible or liquid formulation for patients unable to swallow tablets

A larger tablet can create new risks. Ursodiol has a relatively high daily dose, and excessive tablet size can undermine adherence. A bilayer, multilayer, or high-load formulation could improve dose flexibility but would increase manufacturing complexity and validation requirements.

Strategy 4: Develop patient-centered presentations

Patients with cholestatic liver disease may experience nausea, gastrointestinal symptoms, or difficulty maintaining complex dosing schedules. Formulation opportunities include:

• Smaller film-coated tablets
• Taste-masked oral granules
• Sprinkle capsules
• Oral suspensions
• Orally disintegrating tablets
• Unit-dose sachets
• Calendar or adherence packaging

Taste masking is particularly relevant to liquid and orally disintegrating products. Ursodiol’s sensory profile, suspension stability, sedimentation, preservative system, and dose uniformity would require dedicated development. A liquid product also introduces container-closure, microbiological, and in-use stability requirements.

What patents protect URSO 250?

URSO 250’s core commercial position is not based on a currently visible, blocking patent estate for ursodiol itself. Ursodiol is an established active pharmaceutical ingredient with long-standing regulatory use. Generic products are marketed in the United States.

The relevant intellectual-property categories are more likely to involve:

1. Formulation patents covering a specific excipient combination or particle-engineering method.
2. Process patents covering granulation, milling, coating, or scale-up controls.
3. Dosage-form patents covering liquid, dispersible, multiparticulate, or modified-release products.
4. Method-of-use patents covering a disease or dosing regimen not already encompassed by the approved label.
5. Packaging patents covering adherence systems or dose administration.

A new entrant should distinguish between a patent on a formulation and a patent on a commercially necessary feature. A narrow patent covering a particular polymer grade, surfactant ratio, or milling endpoint may have limited practical value if a noninfringing conventional tablet can meet the same dissolution and bioequivalence requirements.

Orange Book and Paragraph IV implications

FDA Orange Book status should be reviewed by NDA and product strength. The core generic risk for URSO 250 is likely to be ordinary ANDA competition rather than a Paragraph IV campaign against a strong, active patent barrier. A Paragraph IV certification would matter only if an unexpired listed patent covered the reference product or an applicable method of use.

For a differentiated ursodiol product, the patent strategy should target measurable technical characteristics, such as:

• Dissolution at defined pH conditions
• Particle-size limits
• Specific excipient ratios
• Moisture content
• Tablet tensile strength
• Disintegration time
• Stability after defined storage
• Pharmacokinetic performance

Claims should avoid unnecessary dependence on a single supplier or proprietary excipient grade. Broad functional claims are commercially attractive but may face enablement, written-description, obviousness, and anticipation challenges.

When does URSO 250 lose exclusivity?

URSO 250 is a mature product, and its principal regulatory exclusivity period has expired. FDA-approved generic ursodiol tablets are available. The relevant competitive question is therefore not the date of initial loss of exclusivity, but the remaining commercial value of the branded product and the possibility of differentiation through formulation or service.

Exclusivity factor	URSO 250 position
Active ingredient patent	Mature, generic competition established
New chemical entity exclusivity	Expired
Original product exclusivity	Expired
Generic availability	Yes
Biosimilar exposure	None
Primary competitive barrier	Manufacturing, supply, quality, distribution, and brand retention
Main differentiation route	Dose convenience and alternative dosage forms

Because URSO 250 is a small-molecule oral tablet, biosimilar regulation does not apply. Competitive products proceed through generic-drug pathways, including ANDAs, rather than biosimilar applications under section 351(k) of the Public Health Service Act.[2]

Which companies compete with URSO 250?

Competition includes the branded URSO 250 product, generic ursodiol tablet manufacturers, and suppliers of higher-strength ursodiol products. The market is fragmented relative to biologics because tablet manufacture is technically accessible and multiple contract manufacturers can produce conventional immediate-release tablets.

Competitive variables include:

• FDA approval and product availability
• Wholesale acquisition cost and payer reimbursement
• Dose strengths
• Tablet size and scoring
• Product supply continuity
• Authorized-distributor coverage
• State substitution practices
• Formulary placement
• Packaging and adherence support

A generic manufacturer with a lower-cost excipient system may compete effectively without patent ownership. A manufacturer with reliable API sourcing and dual-qualified excipient suppliers may have a stronger commercial position than a company with a narrow formulation patent but fragile supply.

What manufacturing and excipient barriers exist?

The principal barriers are operational rather than legal.

API and powder handling

Ursodiol’s bulk properties can affect blending, hopper flow, die filling, and segregation. Particle-size control is important when the API is a major fraction of the tablet. A change in API supplier or milling process can alter dissolution and compression behavior even when the chemical specification remains unchanged.

Lubrication and dissolution

Magnesium stearate selection, addition rate, and blend time require tight process control. Over-lubrication can produce tablets that meet hardness specifications but fail dissolution targets.

Coating and stability

Film coating must provide acceptable appearance without compromising disintegration. Moisture exposure during coating and storage can affect tablet hardness, friability, and dissolution. Titanium dioxide and talc levels may also influence coating opacity and surface characteristics.

Excipient supply

Commercial risk increases when a formulation depends on one supplier, one grade, or one region. A practical strategy is to qualify at least two suppliers for microcrystalline cellulose, superdisintegrants, povidone, colloidal silicon dioxide, and magnesium stearate. Excipient changes require comparability assessment and may trigger post-approval regulatory work.

FDA’s Inactive Ingredient Database can support excipient selection by identifying prior route and dosage-form use, but inclusion in the database does not establish automatic approval for every concentration or formulation.[3]

How does URSO 250 compare with URSO Forte and liquid ursodiol?

Product concept	Commercial advantage	Main risk
URSO 250 tablet	Dose flexibility and established presentation	Higher pill burden
URSO Forte 500 mg tablet	Fewer tablets per day	Larger tablet and reduced dose granularity
Generic 250 mg tablet	Price competition and substitution	Limited differentiation
Generic 500 mg tablet	Convenience and manufacturing scale	Greater swallowability challenge
Oral suspension	Useful for dysphagia and flexible dosing	Taste, stability, preservation, and dosing accuracy
Sprinkle or granule product	Administration flexibility	Taste masking and packaging complexity
Modified-release product	Potential adherence benefit	Higher clinical and regulatory burden

The strongest near-term opportunity is usually a reliable 250 mg and 500 mg portfolio rather than a novel delivery system. A liquid or sprinkle product may access patients underserved by tablets, but it requires a clearer clinical and commercial rationale.

What generic launch risks exist for URSO 250?

A generic launch faces several risks:

• Failure to match dissolution across required media
• API particle-size drift between development and commercial batches
• Tablet sticking, capping, or lamination at high drug load
• Inconsistent disintegration caused by lubricant overmixing
• Excipient supplier changes
• Large-tablet swallowability problems
• Manufacturing scale-up failures
• Price erosion from multiple ANDA holders
• Limited differentiation in pharmacy substitution channels

A launch strategy should prioritize a robust formulation with multiple qualified excipient sources, conservative process parameters, and a tablet design that supports both dose flexibility and patient acceptability.

What is the revenue opportunity for excipient suppliers?

Excipient suppliers can capture value in four areas:

1. High-functionality grades that improve direct compression, flow, or disintegration.
2. Co-processed excipients that reduce formulation-development time.
3. Low-moisture or low-peroxide materials that improve stability.
4. Technical support for scale-up, supplier qualification, and post-approval change management.

The largest opportunity is unlikely to come from selling a commodity excipient into one branded product. It is more likely to come from supplying multiple generic ursodiol manufacturers with validated grades and regulatory documentation.

Formulation developers can also create licensing opportunities around:

• Micronized or engineered ursodiol
• Improved dissolution systems
• Pediatric or dysphagia-friendly presentations
• Unit-dose adherence packaging
• Stable oral suspensions
• Higher-strength tablets with optimized swallowability

Key Takeaways

• URSO 250 is a mature 250 mg ursodiol tablet with expired core exclusivity and established generic competition.
• The product uses a conventional excipient system centered on microcrystalline cellulose, superdisintegrants, povidone, colloidal silicon dioxide, and magnesium stearate.
• The best near-term formulation opportunity is improved conventional-tablet performance, especially dissolution, manufacturability, and supply resilience.
• URSO Forte 500 mg creates a dose-convenience benchmark but can increase tablet-size and swallowability risks.
• Novel formulations may support stronger differentiation but carry higher bioequivalence, stability, manufacturing, and patent risks.
• The product has no biosimilar exposure. Competition proceeds through small-molecule generic pathways.
• A durable patent position would need to cover a technically necessary and measurable formulation or manufacturing feature, not a readily replaceable commodity excipient.
• Commercial value is most likely to come from lower cost, fewer tablets, improved administration, and reliable supply.

FAQs

Is ursodiol a BCS Class II drug?

Ursodiol has low aqueous solubility and formulation-dependent dissolution behavior. Its formal BCS classification should be established from the applicable FDA product-specific guidance and sponsor bioequivalence data rather than inferred solely from solubility.

Can a generic manufacturer change the URSO 250 excipients?

Yes, an ANDA applicant can use a different inactive-ingredient composition if the product meets applicable pharmaceutical-equivalence, bioequivalence, quality, stability, labeling, and manufacturing requirements.

Is there a commercial opportunity for an ursodiol pediatric formulation?

Potentially. A liquid, granule, or sprinkle formulation could address swallowing and dose-flexibility problems. The primary development challenges are taste masking, suspension uniformity, microbiological control, preservative compatibility, and accurate administration.

Would a novel ursodiol excipient system receive new-drug exclusivity?

Not automatically. A novel formulation may support patent protection, but regulatory exclusivity depends on the approval pathway and the specific statutory requirements. A new excipient alone does not create exclusivity.

What is the most defensible patent strategy for a new ursodiol product?

The strongest strategy would generally combine composition claims with process and performance claims tied to measurable outcomes, such as dissolution, stability, particle-size control, or improved administration. Claims should preserve design-around options and avoid dependence on one supplier.

References

1. U.S. Food and Drug Administration. (2018). URSO 250 (ursodiol) tablets, prescribing information. Allergan USA, Inc.

2. U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations. U.S. Department of Health and Human Services.

3. U.S. Food and Drug Administration. (2024). Inactive Ingredient Database. Center for Drug Evaluation and Research.

4. U.S. Food and Drug Administration. (2024). Ursodiol: Product-specific guidance for generic drug development. Center for Drug Evaluation and Research.