List of Excipients in Branded Drug FLAVOXATE HYDROCHLORIDE

Generic Drugs Containing FLAVOXATE HYDROCHLORIDE

Company	Ingredient	NDC	Excipient
Padagis US LLC	flavoxate hydrochloride	0574-0115	CELLULOSE, MICROCRYSTALLINE
Padagis US LLC	flavoxate hydrochloride	0574-0115	ETHYL ACRYLATE
Padagis US LLC	flavoxate hydrochloride	0574-0115	HYPROMELLOSE
Padagis US LLC	flavoxate hydrochloride	0574-0115	HYPROMELLOSE 2910
Padagis US LLC	flavoxate hydrochloride	0574-0115	LACTOSE MONOHYDRATE
Padagis US LLC	flavoxate hydrochloride	0574-0115	MAGNESIUM STEARATE

What are the Most Frequently-Used Excipients in FLAVOXATE HYDROCHLORIDE?

# Of NDCs	Excipient
1	CALCIUM PHOSPHATE, DIBASIC, DIHYDRATE
2	CELLULOSE, MICROCRYSTALLINE
3	DIBASIC CALCIUM PHOSPHATE DIHYDRATE
2	ETHYL ACRYLATE
1	HYPROMELLOSE
4	HYPROMELLOSE 2910

# Flavoxate Hydrochloride Excipient Strategy and Commercial Opportunities

Last updated: September 6, 2026

Flavoxate hydrochloride is an established oral urinary antispasmodic with limited current innovation around the active ingredient. Commercial value is more likely to come from improved tablets, extended-release delivery, regional registration, supply reliability, and line extensions than from new chemical-entity exclusivity. The strongest product strategy is a stable, rapidly disintegrating immediate-release tablet supported by robust dissolution data, with controlled-release or combination products as higher-risk opportunities.

What is the commercial profile of flavoxate hydrochloride?

Flavoxate hydrochloride is used to relieve urinary urgency, frequency, dysuria, nocturia, and bladder spasm associated with conditions such as cystitis, prostatitis, urethritis, and urocystitis. It is generally positioned as a symptomatic treatment rather than an anti-infective therapy.[1]

Attribute	Commercial relevance
Active ingredient	Flavoxate hydrochloride
Therapeutic area	Urology and urinary antispasmodics
Common dosage form	Oral immediate-release tablet
Common strengths	100 mg and 200 mg, depending on market
Drug class	Urinary tract antispasmodic
Reference brand	Urispas and country-specific brands
Regulatory status	Established prescription product in multiple markets
Biologic status	Small molecule; biosimilar pathway is not relevant
Main competition	Oxybutynin, tolterodine, solifenacin, trospium, darifenacin, mirabegron and generic anticholinergic products
Primary commercial constraint	Mature molecule with limited composition-of-matter exclusivity

The commercial profile differs by country. In some markets, flavoxate remains available as a branded or generic prescription product. In others, it has limited visibility relative to newer overactive-bladder medicines. Product positioning depends on local treatment guidelines, reimbursement, physician familiarity and the availability of competing antimuscarinic agents.

What excipients are suitable for flavoxate hydrochloride tablets?

The preferred excipient system depends on the target dosage form, manufacturing process and dissolution profile. For an immediate-release tablet, the formulation should prioritize content uniformity, rapid disintegration, mechanical strength and protection from moisture.

Immediate-release tablet strategy

A conventional direct-compression or wet-granulation formula may contain:

Functional requirement	Candidate excipient classes	Development purpose
Dilution	Microcrystalline cellulose, lactose monohydrate, mannitol, dibasic calcium phosphate	Adjust tablet weight and improve compressibility
Binder	Povidone, copovidone, hydroxypropyl cellulose	Improve granule and tablet strength
Disintegrant	Croscarmellose sodium, crospovidone, sodium starch glycolate	Promote rapid breakup and dissolution
Glidant	Colloidal silicon dioxide	Improve powder flow
Lubricant	Magnesium stearate, sodium stearyl fumarate	Reduce ejection force and sticking
Moisture control	Low-moisture fillers, protective film coating, high-barrier packaging	Reduce degradation and physical instability
Coating	Hypromellose, polyvinyl alcohol, polyethylene glycol, titanium dioxide or approved colorants	Improve handling, identification and swallowability

Microcrystalline cellulose is a practical starting point where direct compression is feasible. Lactose can reduce cost and improve tablet mass but may introduce compatibility and moisture-management considerations. Mannitol can improve mouthfeel and is useful where a lower-density, more patient-friendly tablet is desired, although it can increase cost.

Crospovidone or croscarmellose sodium is generally preferable to relying on sodium starch glycolate alone when rapid disintegration and consistent dissolution are commercial priorities. The final selection should be based on dissolution performance, not on excipient convention.

Wet granulation versus direct compression

Direct compression can reduce manufacturing steps and support low-cost generic production. It is attractive where flavoxate hydrochloride has acceptable flow, compressibility and content-uniformity performance.

Wet granulation may be preferred where the active has poor flow, segregation risk or inadequate tabletability. It can improve dose uniformity but adds exposure to water, drying heat and process variability. A low-moisture granulation approach or dry granulation may be more suitable if stability studies show sensitivity to humidity.

For a 200 mg tablet, the active load is commercially manageable. For a 100 mg tablet, direct compression offers greater flexibility in selecting a compact, easy-to-swallow unit dose.

What formulation patents could protect flavoxate hydrochloride products?

The active ingredient is an old small molecule, so new commercial protection is more likely to arise from formulation or manufacturing claims than from composition-of-matter claims.

Potentially protectable technical areas include:

• Modified-release matrices that reduce dosing frequency.
• Multiparticulate systems that separate immediate and delayed release.
• Taste-masked oral granules or orally disintegrating tablets.
• Low-moisture formulations with defined impurity limits.
• Specific excipient ratios that improve dissolution or content uniformity.
• Film-coating systems that improve stability without delaying release.
• Fixed-dose combinations with urinary analgesic, anti-inflammatory or anti-infective agents.
• Process controls that reduce polymorphic conversion or batch variability.
• Unit-dose sachets, sprinkle capsules or liquid suspensions for patients with swallowing difficulties.

A formulation patent must show more than routine substitution of excipients. Stronger claims would link a defined composition or process to a measurable result, such as a dissolution profile, stability threshold, impurity reduction or improved bioavailability.

An orally disintegrating formulation could offer a practical differentiation path, but the product must address the taste, dose load and solid-state behavior of flavoxate hydrochloride. A liquid product would create pediatric and swallowing-related opportunities, but it would require stronger control of solubility, sedimentation, preservative performance and dose uniformity.

What is the FDA regulatory status of flavoxate hydrochloride?

Flavoxate hydrochloride is regulated as a prescription drug in the United States. Urispas labeling identifies flavoxate hydrochloride tablets for relief of symptoms associated with urinary tract spasm and related conditions.[1]

The FDA’s Drugs@FDA and Orange Book systems are the primary sources for determining whether a specific reference product, abbreviated new drug application or patent listing remains active.[2,3] The regulatory record for an old molecule should be reviewed separately from current commercial availability because a product can be discontinued, transferred or marketed by a different holder without changing the underlying active ingredient.

For a new generic tablet, the principal regulatory issues are:

1. Pharmaceutical equivalence to the reference product.
2. Demonstration of bioequivalence where required.
3. Matching strength, route and dosage form.
4. Acceptable dissolution and stability.
5. Compliance with current manufacturing and labeling requirements.
6. Suitability of all inactive ingredients under FDA requirements.

The FDA Inactive Ingredient Database is useful for assessing prior use of excipients by route and dosage form.[4] Prior use does not replace a complete safety and quality assessment, particularly for a new dosage form, pediatric use or a substantially higher exposure to an excipient.

When does flavoxate hydrochloride lose exclusivity?

Flavoxate hydrochloride is a mature small-molecule active ingredient. Its core composition-of-matter exclusivity is not a meaningful barrier to current generic development. Commercial exclusivity is more likely to depend on:

• A specific reference-product approval.
• Any unexpired formulation or method-of-use patent.
• Regulatory exclusivity attached to a particular product.
• Local market registration and data-protection rules.
• Manufacturing capability and distribution agreements.

Publicly accessible FDA reference sources do not indicate that a broad, active composition-of-matter patent estate currently protects flavoxate hydrochloride itself. Any Orange Book patent analysis must be performed against the relevant product and jurisdiction because patent listings can differ by dosage form, label and approval holder.[3]

What generic entry risks exist?

Generic entry risk is high where the market has:

• Multiple established manufacturers.
• No active formulation patent.
• Simple immediate-release tablets.
• Low development cost.
• Limited clinical differentiation.
• Price-sensitive reimbursement.

The main barriers are commercial rather than legal. A supplier must demonstrate consistent API quality, control impurities, achieve competitive cost of goods and secure local registration. A small market can still be difficult to enter if annual demand is fragmented across countries and batch sizes are low.

Are there Paragraph IV challenges for flavoxate hydrochloride?

Paragraph IV litigation is generally relevant when a generic applicant challenges an unexpired patent listed for an FDA-approved reference product. Because flavoxate hydrochloride is an old active ingredient and the commercial product is mature, the principal Paragraph IV opportunity would involve a formulation, method-of-use or other product-specific patent rather than the active ingredient itself.

A credible challenge requires:

• Identification of an active Orange Book-listed patent.
• A non-infringement, invalidity or unenforceability position.
• An ANDA product that creates a justiciable patent issue.
• A commercial market large enough to justify litigation cost.

No major, widely recognized current Paragraph IV dispute is associated with flavoxate hydrochloride in the public materials cited here. The absence of prominent litigation is consistent with a low-value, mature generic market, but it does not establish that no jurisdiction-specific dispute exists.

What excipient-led commercial opportunities exist?

1. Premium immediate-release tablets

The most practical opportunity is a high-quality generic tablet with:

• Fast and reproducible disintegration.
• Consistent dissolution across the shelf life.
• Low tablet weight.
• Film coating for swallowability.
• Blister packaging for moisture protection.
• Reliable global supply.

The product would compete on availability, quality and procurement performance rather than on patent exclusivity.

2. Modified-release flavoxate

A once- or twice-daily product could reduce pill burden. Potential systems include hydrophilic matrices, coated multiparticulates and osmotic or membrane-controlled platforms.

The technical risk is substantial. Release rate must be controlled despite variable gastrointestinal conditions, and the product may require a new clinical or bioequivalence strategy. A modified-release formulation would also face direct competition from modern once-daily overactive-bladder therapies.

3. Oral suspension or dispersible granules

A liquid or sprinkle product could serve patients who cannot swallow tablets. The main development issues are:

• Adequate solubility or uniform suspension.
• Chemical and physical stability.
• Preservative compatibility.
• Dose-measurement accuracy.
• Palatability.
• Container-closure performance.

This opportunity is more differentiated than a standard tablet but has a smaller initial market and higher quality-control burden.

4. Combination products

A combination with an anti-infective would raise regulatory and clinical complexity because urinary symptoms can occur with or without infection. A combination with an analgesic or anti-inflammatory agent may be commercially logical but would require a clear therapeutic rationale, dose justification and interaction assessment.

A fixed-dose combination is more likely to obtain defensible formulation claims if it demonstrates a specific pharmacokinetic, adherence or clinical benefit. A simple co-pack is easier to commercialize but offers weaker intellectual-property protection.

5. Regional contract manufacturing

Many markets continue to rely on imported finished products or APIs. A manufacturer that provides validated flavoxate hydrochloride tablets, private-label packaging and local dossier support could capture business without developing a novel dosage form.

The strongest model may combine:

• Qualified API sources.
• Dual-site finished-dose manufacturing.
• Flexible batch sizes.
• Local-language packaging.
• Stability data for climatic zones III and IV.
• Regulatory support for multiple countries.

How does flavoxate compare with competing urinary antispasmodics?

Product	Typical differentiation	Generic pressure	Excipient opportunity
Flavoxate hydrochloride	Established urinary antispasmodic; symptomatic use	High	Stable immediate-release tablet, liquid or modified release
Oxybutynin	Broad generic availability; oral and transdermal forms	High	Transdermal and extended-release technologies are more developed
Tolterodine	Overactive-bladder positioning; immediate and extended release	High	Modified release and abuse-resistant packaging
Solifenacin	Once-daily dosing and branded history	Moderate to high	Film-coated tablets and alternate dosage forms
Trospium	Quaternary antimuscarinic profile	Moderate to high	Extended release and food-effect control
Mirabegron	Beta-3 agonist; non-antimuscarinic mechanism	Increasing	Controlled release and combination products

Flavoxate’s advantage is its established manufacturing base and relatively simple oral dosage form. Its weakness is limited differentiation against once-daily products and newer pharmacologic classes.

What patent litigation, licensing and settlement issues affect the market?

The relevant legal risk is likely to arise from product-specific formulation patents rather than from the active ingredient. Standard diligence should review:

• Orange Book listings for the reference product.
• FDA approval history.
• ANDA applicants and Paragraph IV notices.
• Patent assignments and continuations.
• National patent registers in target markets.
• License and distribution agreements.
• Manufacturing-site ownership and API supply rights.

No prominent current licensing or settlement structure is apparent from the public regulatory sources cited for this analysis. In a mature molecule market, commercial agreements are more likely to concern trademark rights, regional distribution, API supply or private-label manufacturing than exclusionary patent licenses.

What is the revenue exposure and generic launch outlook?

Flavoxate hydrochloride is unlikely to support large blockbuster-level revenue in a conventional immediate-release tablet market. Revenue potential depends on geography, price, reimbursement and the ability to aggregate demand across countries.

Launch model	Investment level	Differentiation	Expected commercial profile
Standard 100 mg or 200 mg generic tablet	Low	Low	Volume and procurement driven
Premium film-coated tablet	Low to moderate	Moderate	Better adherence and private-label positioning
Moisture-protected blister product	Moderate	Moderate	Useful in hot and humid markets
Modified-release tablet	Moderate to high	High	Potential premium, higher regulatory risk
Oral suspension or dispersible product	Moderate	High	Smaller but less crowded segment
Fixed-dose combination	High	High	Requires clinical and regulatory justification
Regional contract-manufacturing platform	Moderate	Commercial rather than technical	Recurring B2B revenue

A generic launch is most plausible in markets where the reference product remains registered, local demand is measurable and procurement is not dominated by a single incumbent. A launch based only on U.S. demand would face a limited commercial ceiling unless the product gains a differentiated dosage form or a broader urology portfolio position.

How strong is the flavoxate hydrochloride patent estate?

The patent estate is weak for the active ingredient and potentially moderate for a newly developed dosage form.

IP category	Likely strength	Commercial implication
Composition of matter	Low	No meaningful barrier for modern entrants
Standard immediate-release tablet	Low	Easily replicated unless a specific patent applies
Excipient ratio or process claim	Low to moderate	Protection depends on technical effect
Modified-release formulation	Moderate	Potentially defensible if clinically relevant
Oral suspension or dispersible dosage form	Moderate	Differentiation possible, but market size is limited
Method of treatment	Low to moderate	Scope depends on jurisdiction and claim drafting
Trademark and trade dress	Moderate	Can support brand recognition but not generic exclusion
Manufacturing know-how	Moderate	May protect quality and cost position without blocking entry

Geographic coverage is likely to be more important than patent scope. A product can be commercially viable in markets with weak local competition even when it has no meaningful patent protection.

Key Takeaways

• Flavoxate hydrochloride is a mature, genericized urinary antispasmodic.
• The strongest near-term opportunity is a reliable immediate-release tablet using a conventional, moisture-controlled excipient system.
• Microcrystalline cellulose, a superdisintegrant, a low-level binder, colloidal silicon dioxide and a suitable lubricant are practical development starting points.
• Modified-release, liquid and orally disintegrating products offer greater differentiation but carry higher regulatory and technical risk.
• Biosimilar risk is not relevant because flavoxate hydrochloride is a small molecule.
• Broad composition-of-matter exclusivity is not a current commercial barrier.
• Formulation, process, trademark, supply and regional registration strategies are more relevant than active-ingredient patents.
• Generic entry risk is high in markets with established suppliers and simple tablet requirements.
• A regional manufacturing and private-label strategy may offer better returns than a standalone U.S. generic launch.
• No major current Paragraph IV dispute or public settlement structure is identified in the cited regulatory sources.

FAQs

Is flavoxate hydrochloride still commercially viable?

Yes, but mainly as a focused generic, regional or private-label product. Commercial viability depends on local registration, procurement demand and competition from newer overactive-bladder therapies.

Which excipient is best for flavoxate hydrochloride tablets?

No single excipient is universally best. Microcrystalline cellulose combined with crospovidone or croscarmellose sodium is a practical starting platform, subject to dissolution, stability and compressibility testing.

Can flavoxate hydrochloride be developed as an extended-release product?

Yes. Hydrophilic matrices, coated multiparticulates and membrane-controlled systems are possible. The product would require a clear pharmacokinetic and clinical rationale because it would compete with established once-daily therapies.

Does flavoxate hydrochloride have biosimilar competition?

No. Biosimilars apply to biological products. Flavoxate hydrochloride is a chemically synthesized small molecule and is developed through generic-drug pathways.

What is the most defensible commercial differentiation for flavoxate hydrochloride?

The strongest practical differentiation is a combination of stable product performance, rapid dissolution, moisture-protective packaging, regional regulatory support and reliable supply. A novel dosage form may create stronger intellectual-property value but requires substantially more development investment.

References

1. DailyMed. (n.d.). Urispas- flavoxate hydrochloride tablet, film coated. U.S. National Library of Medicine. https://dailymed.nlm.nih.gov/

2. U.S. Food and Drug Administration. (n.d.). Drugs@FDA: FDA-approved drugs. https://www.accessdata.fda.gov/scripts/cder/daf/

3. U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations, commonly known as the Orange Book. https://www.fda.gov/drugs/drug-approvals-and-databases/approved-drug-products-therapeutic-equivalence-evaluations-orange-book

4. U.S. Food and Drug Administration. (n.d.). Inactive Ingredient Database. https://www.accessdata.fda.gov/scripts/sda/sdNavigation.cfm?sd=inactiveIngredientListing