List of Excipients in Branded Drug URSODIOL

Company	Tradename	Ingredient	NDC	Excipient	Potential Generic Entry
Actavis Pharma Inc	URSODIOL	ursodiol	0591-2998	CARNAUBA WAX
Actavis Pharma Inc	URSODIOL	ursodiol	0591-2998	CELLULOSE, MICROCRYSTALLINE
Actavis Pharma Inc	URSODIOL	ursodiol	0591-2998	CETYL ALCOHOL

Generic Drugs Containing URSODIOL

Company	Ingredient	NDC	Excipient
Mylan Pharmaceuticals Inc	ursodiol	0378-1730	CELLULOSE, MICROCRYSTALLINE
Mylan Pharmaceuticals Inc	ursodiol	0378-1730	D&C YELLOW NO. 10
Mylan Pharmaceuticals Inc	ursodiol	0378-1730	FD&C BLUE NO. 1

What are the Most Frequently-Used Excipients in URSODIOL?

# Of NDCs	Excipient
6	ALCOHOL
5	ALUMINUM OXIDE
8	AMMONIA

Ursodiol Excipient Strategy, Formulation Patents, and Commercial Opportunities

Last updated: August 2, 2026

Ursodiol is a mature generic bile acid with limited composition-of-matter protection and relatively low barriers to conventional oral products. Commercial opportunity is concentrated in formulation differentiation: improved dissolution, lower pill burden, pediatric liquid delivery, sprinkle products, taste masking, and stable products for patients with swallowing or absorption challenges. The strongest near-term strategy is usually a differentiated 505(b)(2) or specialty generic product rather than a standard immediate-release tablet.

What is ursodiol and how is it regulated?

Ursodiol, also called ursodeoxycholic acid or UDCA, is a hydrophilic bile acid used in the United States for primary biliary cholangitis and dissolution of selected radiolucent cholesterol gallstones. FDA-approved products include Actigall capsules and Urso 250 and Urso Forte tablets. Generic ursodiol products are also approved through the abbreviated new drug application pathway.

Attribute	Commercial and regulatory position
Active ingredient	Ursodiol, ursodeoxycholic acid
Therapeutic class	Bile acid
Main U.S. indications	Primary biliary cholangitis; dissolution of radiolucent cholesterol gallstones
Common dosage forms	Capsules, 250 mg and 300 mg tablets, 500 mg tablets
Primary U.S. pathways	ANDA for equivalent generics; 505(b)(2) for differentiated products
Reference products	Actigall; Urso 250; Urso Forte
Biologic status	Not a biologic; biosimilar rules do not apply
Patent position	Mature active ingredient with limited practical protection for conventional immediate-release products

FDA labeling identifies ursodiol as a prescription drug with dose regimens that can create a substantial daily tablet or capsule burden. PBC treatment is generally weight-based, while gallstone dissolution requires prolonged administration. Those characteristics create a commercial rationale for dosage-form and administration improvements rather than new active-ingredient protection (U.S. Food and Drug Administration [FDA], 2024a, 2024b).

What excipients are used in marketed ursodiol products?

Marketed ursodiol products use conventional oral excipients. Exact compositions differ by manufacturer and dosage form, so the inactive-ingredient profile must be verified against the current FDA label or DailyMed record for each product.

Typical capsule excipients

Ursodiol capsules commonly use combinations of:

• Pregelatinized starch or other starch-based fillers
• Sodium starch glycolate or a comparable disintegrant
• Colloidal silicon dioxide
• Magnesium stearate
• Gelatin capsule shells
• Titanium dioxide and colorants, depending on the product

These excipients support powder flow, capsule filling, disintegration, and manufacturing robustness. They do not materially differentiate a product unless the sponsor controls a specific composition, process, or performance limitation.

Typical tablet excipients

Ursodiol tablets can contain:

• Microcrystalline cellulose
• Starch
• Povidone
• Crospovidone
• Magnesium stearate
• Talc
• Hypromellose
• Polysorbate 80
• Sodium lauryl sulfate
• Film-coating materials
• Titanium dioxide or other pigments

The excipient selection is often driven by tablet hardness, friability, disintegration, dissolution, coating performance, and dose uniformity. A high-dose 500 mg tablet creates more demanding compression and swallowability requirements than a 250 mg tablet.

What excipient constraints apply?

Ursodiol formulation development must account for:

1. Low aqueous solubility and dissolution sensitivity.
2. The hydrophobic character of the steroid nucleus.
3. Potential variability from particle size and polymorphic form.
4. Patient exposure to a high daily dose.
5. The need to preserve dissolution across gastrointestinal pH conditions.
6. Compatibility with gelatin, film coatings, surfactants, and moisture-sensitive excipients.
7. The risk that excipient changes alter bioequivalence or gastrointestinal tolerability.

FDA’s inactive-ingredient database is useful for identifying previously used excipients and route-specific precedent. It does not establish approval for a new concentration, route, or product configuration (FDA, 2024c).

How can excipients improve ursodiol dissolution and absorption?

The most technically relevant formulation problem is dissolution. Ursodiol is administered orally, and conventional products depend on gastrointestinal dispersion and dissolution before absorption and enterohepatic circulation.

Micronization and particle engineering

Micronized ursodiol can increase surface area and improve dissolution. A patent position based only on routine micronization may be weak unless the sponsor demonstrates a defined particle-size distribution, superior dissolution profile, improved exposure, or reduced variability.

Potential claim elements include:

• D90 or D50 particle-size limits
• Specific surface area
• Crystalline form or polymorph
• Milling process
• Excipient-to-drug ratio
• Dissolution threshold at multiple pH values
• Stability after compression or granulation

Particle-size claims are more defensible when linked to measurable product performance. A size range without a demonstrated technical effect may face obviousness and enablement challenges.

Surfactants and wetting agents

Polysorbates, sodium lauryl sulfate, poloxamers, and related wetting agents can improve powder wetting and dissolution. The commercial advantages are potentially significant, but surfactant selection must address:

• Oxidative and hydrolytic stability
• Local gastrointestinal tolerability
• Regulatory precedent
• Interaction with capsule shells
• Foam formation during manufacturing
• Dissolution reproducibility

A formulation patent may be stronger when it claims a narrow surfactant concentration range linked to a specific dissolution result rather than broadly claiming any surfactant.

Lipid-based systems

Self-emulsifying drug delivery systems, lipid suspensions, and softgel formulations may improve dispersion of ursodiol. These systems are technically attractive for a poorly soluble compound but introduce development and manufacturing complexity.

Important variables include:

• Medium-chain triglycerides
• Long-chain glycerides
• Surfactant and cosurfactant ratios
• Emulsion droplet size
• Fill weight
• Capsule-shell compatibility
• Precipitation after dilution in gastrointestinal fluid

A lipid-based product may justify a 505(b)(2) strategy if it produces a clinically meaningful or regulatory-relevant difference from a conventional capsule or tablet. It is less attractive when the product only improves in vitro dissolution without a clear patient benefit or viable regulatory pathway.

Amorphous solid dispersions

Polymers such as povidone, copovidone, hypromellose acetate succinate, or Soluplus may be evaluated for amorphous solid dispersion systems. The principal risks are recrystallization, moisture sensitivity, large excipient load, and scale-up complexity.

An effective patent should address:

• Drug-loading range
• Polymer identity and molecular weight
• Solid-state characterization
• Residual solvent limits
• Recrystallization resistance
• Dissolution after accelerated storage
• Manufacturing process parameters

This route has greater technical differentiation than a standard tablet, but development costs and stability risk are also higher.

What formulation patents could protect ursodiol products?

The strongest potential patent categories are formulation and manufacturing claims tied to objective performance.

Patent category	Potential claim scope	Commercial strength
Particle engineering	Particle size, surface area, polymorph, milling	Moderate if linked to performance
Solid dispersion	Polymer matrix, drug loading, solid state	Moderate to strong
Lipid formulation	Oil, surfactant, cosurfactant, droplet size	Moderate
Oral suspension	Suspending system, sedimentation, redispersibility	Moderate
Taste masking	Coating, complexation, ion exchange, flavor system	Moderate for pediatric use
Modified release	Matrix, coating, release profile	Variable; requires clinical rationale
Manufacturing process	Granulation, drying, compression, coating	Moderate if process-specific
Combination product	Ursodiol with another active ingredient	Potentially strong, but clinical and regulatory burden is high

Composition claims should be supported by comparative data against conventional ursodiol products. Useful evidence includes dissolution, pharmacokinetics, food-effect data, stability, dose uniformity, and patient administration studies.

What pediatric and patient-centric excipient opportunities exist?

Pediatric and dysphagia products represent the clearest underserved formulation segment. Ursodiol is used in pediatric hepatobiliary practice, including settings where administration of tablets or capsules is difficult. Some pediatric use may be outside the principal U.S. labeled indications, which affects promotional and regulatory strategy.

Oral liquids

An oral suspension or solution could reduce swallowing burden and support weight-based dosing. Key excipient issues include:

• Palatability and bitterness
• Chemical and microbial stability
• Sedimentation and redispersibility
• Dose uniformity after shaking
• Syringe compatibility
• Preservative selection
• Sugar-free and alcohol-free options
• Low-temperature stability

A suspension is more practical than a true aqueous solution if solubility remains limiting. A sponsor could seek protection for particle engineering, suspending agents, wetting systems, taste masking, and a defined in-use shelf life.

Sprinkle and dispersible products

A sprinkle capsule, orally disintegrating tablet, or dispersible granule could target patients who cannot swallow standard dosage forms. Development must establish that administration with soft food does not compromise stability, content uniformity, or dissolution.

Potential product advantages include:

• Lower caregiver burden
• More flexible dose titration
• Reduced tablet splitting
• Improved administration in pediatric and geriatric populations
• Compatibility with enteral feeding procedures, if clinically validated

Taste masking

Ursodiol’s bile-acid character can create a challenging taste profile. Taste-masking technologies include polymer coatings, lipid barriers, cyclodextrin complexation, ion-exchange resins, and multiparticulate systems. The commercial value depends on palatability testing, not merely excipient selection.

When does ursodiol lose exclusivity?

Ursodiol’s active ingredient is long off patent, and conventional generic competition is established. The relevant exclusivity question is therefore product-specific rather than molecule-wide.

Exclusivity issue	Ursodiol position
New chemical entity exclusivity	Expired
Orphan-drug exclusivity	Not a general protection for all ursodiol products
Pediatric exclusivity	Must be assessed by product and FDA grant
Conventional composition-of-matter patent	No meaningful current barrier for standard ursodiol
Formulation patent	Product-specific; may exist for a differentiated formulation
Method-of-use patent	Must be assessed by indication, claim scope, and listing status
Generic substitution	Available for approved equivalent products, subject to state substitution rules

Because ursodiol is a small-molecule generic, biosimilar competition is irrelevant. Competitors would generally use the ANDA pathway for a therapeutically equivalent product or 505(b)(2) for a differentiated formulation.

What is the Orange Book status of ursodiol?

The Orange Book is the principal source for approved drug products, reference listed drugs, therapeutic-equivalence evaluations, patents, and regulatory exclusivity. Ursodiol sponsors should review current Orange Book entries for Actigall, Urso 250, Urso Forte, and each relevant reference listed drug before filing or licensing a product (FDA, 2024d).

For a conventional generic strategy, the key diligence points are:

• Identification of the correct reference listed drug
• Dosage-form and strength matching
• Therapeutic-equivalence rating
• Current patent listings
• Pediatric exclusivity
• Labeling differences
• Withdrawal or discontinuation status
• Manufacturing-site information

Patent listings can change, and an Orange Book absence of a listed patent does not eliminate non-Orange-Book patent or regulatory risk. A formulation sponsor should also search USPTO records, international patent databases, litigation dockets, and product labels.

Are there Paragraph IV challenges involving ursodiol?

Paragraph IV risk is generally lower for mature ursodiol products than for recently approved branded drugs because the principal active ingredient and conventional formulations have long been genericized. A Paragraph IV certification could still arise against a later-listed formulation, method-of-use patent, or other listed patent.

For a prospective ANDA:

1. Identify the reference listed drug.
2. Review every currently listed patent and exclusivity entry.
3. Select Paragraph I, II, III, or IV certification as applicable.
4. Prepare a noninfringement, invalidity, or unenforceability position for any Paragraph IV filing.
5. Assess the possibility of a 30-month stay if the NDA holder files suit within the statutory period.

The commercial value of a Paragraph IV strategy is limited when multiple generic competitors already sell conventional ursodiol. It becomes more attractive when the target is a high-value formulation with limited competition.

What patent litigation and settlement risks affect ursodiol?

No broad, molecule-level litigation barrier is generally expected for standard ursodiol tablets and capsules. The principal risks would arise from:

• A branded formulation patent
• A delivery-system patent
• A method-of-use patent
• A patent covering a specific particle-size or solid-state form
• Manufacturing-process claims
• Contract-manufacturing confidentiality or trade-secret disputes

Settlement agreements should be reviewed for launch dates, authorized-generic rights, supply obligations, field-of-use restrictions, and admission or non-admission provisions. In a low-priced generic market, litigation economics can be unfavorable unless the target product has limited competition or a significant formulation premium.

Which companies are competing in ursodiol?

Competition is distributed across branded products, authorized or independent generics, specialty pharmacies, and international manufacturers. Relevant commercial categories include:

• Original or branded reference products
• FDA-approved generic capsules and tablets
• Specialty manufacturers with hospital or hepatology distribution
• Compounding pharmacies offering oral suspensions
• International suppliers of ursodeoxycholic acid
• Potential developers of pediatric or modified-delivery products

The most defensible competitive advantage is likely to come from delivery and service rather than the active ingredient. A sponsor with validated pediatric dosing, stable liquid packaging, reliable supply, and payer access could compete even in a low-cost generic category.

What commercial opportunities exist for ursodiol excipient innovation?

Opportunity ranking

Opportunity	Technical value	Regulatory burden	Commercial attractiveness
Standard 250 mg or 300 mg tablet	Low	Low	Low
Standard 500 mg tablet	Low to moderate	Low	Moderate if manufacturing cost is low
High-load capsule or tablet	Moderate	Low to moderate	Moderate
Pediatric oral suspension	High	Moderate	High in a targeted market
Sprinkle or dispersible dosage form	High	Moderate	High
Taste-masked multiparticulates	High	Moderate to high	Moderate to high
Lipid-based formulation	Moderate to high	Moderate to high	Selective
Amorphous solid dispersion	High	High	Selective
Modified-release product	Moderate	High	Uncertain
Compounded suspension platform	Moderate	Pharmacy-specific	Localized

The best opportunity is a product that solves an administration problem and has a credible reimbursement or specialty-distribution model. A technically sophisticated excipient system without a measurable patient benefit is unlikely to support a durable premium.

How strong is the ursodiol patent estate?

The patent estate for conventional ursodiol is weak because the molecule and standard oral dosage forms are mature. Patent strength improves when a product has:

• Narrow, reproducible composition claims
• Clear comparative dissolution or pharmacokinetic advantages
• Stable solid-state characteristics
• Demonstrated pediatric palatability
• A validated manufacturing process
• Claims that are difficult to design around
• A regulatory pathway that creates meaningful market exclusivity

Trade secrets may be more valuable than patents for specialized manufacturing parameters, coating conditions, taste-masking processes, and scale-up controls. Sponsors should use a combined patent and know-how strategy.

Key Takeaways

• Ursodiol has limited remaining protection at the active-ingredient level.
• Conventional tablets and capsules face low patent barriers and established generic competition.
• Excipient innovation is most commercially relevant for dissolution, taste masking, suspension stability, and swallowability.
• Pediatric liquids, sprinkle products, and dispersible formulations offer the clearest differentiation.
• A 505(b)(2) pathway may be appropriate for a clinically meaningful delivery improvement; an ANDA is more suitable for a therapeutically equivalent generic.
• Orange Book and FDA labeling review must be product-specific and current.
• Biosimilar risk does not apply because ursodiol is a small-molecule drug.
• Formulation patents require comparative performance data and carefully defined claim boundaries.
• Manufacturing know-how may provide stronger practical protection than broad excipient claims.
• Revenue upside depends more on dosage-form differentiation, supply reliability, and specialty distribution than on the ursodiol molecule itself.

FAQs

Can ursodiol be formulated as an oral solution?

A true oral solution may be difficult because ursodiol has limited aqueous solubility. An oral suspension, solubilized system, or lipid-based formulation is generally more practical, subject to stability, dose uniformity, and palatability testing.

Which excipients are most useful for ursodiol taste masking?

Polymer coatings, lipid barriers, cyclodextrins, ion-exchange resins, and multiparticulate systems are potential options. The best choice depends on dissolution impact, pediatric palatability, stability, and manufacturing cost.

Is an ursodiol suspension eligible for an ANDA?

An ANDA may be possible only when the product meets the applicable requirements for pharmaceutical equivalence, bioequivalence, labeling, and reference-product comparison. A materially different delivery system may require a 505(b)(2) application.

Are ursodiol formulations eligible for orphan-drug exclusivity?

Orphan-drug exclusivity is indication-specific and does not automatically apply to all ursodiol products. A sponsor would need to satisfy FDA orphan-drug requirements for a defined rare disease or condition and obtain the relevant designation and approval.

Can an ursodiol formulation patent block generic tablets?

A formulation patent generally cannot block a noninfringing generic that does not practice the patented formulation. Its practical effect depends on claim scope, Orange Book listing, litigation timing, and the generic applicant’s certification and design-around position.

References

1. U.S. Food and Drug Administration. (2024a). Actigall (ursodiol) capsule prescribing information.
2. U.S. Food and Drug Administration. (2024b). Urso 250 and Urso Forte (ursodiol) tablet prescribing information.
3. U.S. Food and Drug Administration. (2024c). Inactive ingredient database.
4. U.S. Food and Drug Administration. (2024d). Approved drug products with therapeutic equivalence evaluations: Orange Book.
5. U.S. Food and Drug Administration. (2024e). ANDA submissions: Refuse-to-receive standards and patent certification requirements.
6. DailyMed. (2024). Ursodiol capsule and tablet labeling records. National Library of Medicine.