List of Excipients in Branded Drug PENTOXIFYLLINE

Generic Drugs Containing PENTOXIFYLLINE

Company	Ingredient	NDC	Excipient
NCS HealthCare of KY Inc dba Vangard Labs	pentoxifylline	0615-4523	CELLULOSE, MICROCRYSTALLINE
NCS HealthCare of KY Inc dba Vangard Labs	pentoxifylline	0615-4523	D&C RED NO. 30
NCS HealthCare of KY Inc dba Vangard Labs	pentoxifylline	0615-4523	FD&C BLUE NO. 2
NCS HealthCare of KY Inc dba Vangard Labs	pentoxifylline	0615-4523	FD&C YELLOW NO. 6

What are the Most Frequently-Used Excipients in PENTOXIFYLLINE?

# Of NDCs	Excipient
3	CELLULOSE, MICROCRYSTALLINE
5	D&C RED NO. 30
2	D&C YELLOW NO. 10 ALUMINUM LAKE
5	FD&C BLUE NO. 2

Pentoxifylline Excipient Strategy and Commercial Opportunities

Last updated: August 9, 2026

Pentoxifylline is an off-patent methylxanthine derivative sold primarily as a 400 mg extended-release oral tablet for intermittent claudication associated with chronic occlusive arterial disease. The commercial opportunity is not based on molecule exclusivity. It depends on reliable modified-release performance, lower manufacturing cost, differentiated packaging, global registration, and improved tolerability or adherence.

The strongest product strategy is a robust extended-release tablet with predictable dissolution under fed and fasted conditions, resistance to alcohol-induced dose dumping, low tablet weight, and a supply chain based on widely available compendial excipients. Patent opportunities are limited to genuinely differentiated formulation, manufacturing, or delivery claims.

What is the FDA regulatory status of pentoxifylline?

Pentoxifylline is an FDA-approved prescription drug in an extended-release 400 mg tablet. The reference product is associated with Trental, historically marketed by Hoechst Marion Roussel and later Sanofi-related entities. Generic pentoxifylline extended-release tablets are marketed in the United States through abbreviated new drug applications.

The principal regulatory facts are:

Attribute	Pentoxifylline
Active ingredient	Pentoxifylline
Dosage form	Extended-release tablet
Common strength	400 mg
U.S. indication	Intermittent claudication associated with chronic occlusive arterial disease
Regulatory pathway for standard generic	ANDA under Section 505(j)
Reference product type	Extended-release prescription tablet
Pediatric exclusivity	No material commercial pediatric exclusivity identified for the established product
Biosimilar exposure	None; pentoxifylline is a small molecule
Primary regulatory risk	Demonstrating equivalent extended-release pharmacokinetics and dissolution

The FDA labeling describes gradual improvement in walking distance and symptoms rather than immediate relief. The labeling also permits dose reduction when adverse reactions occur, which makes gastrointestinal tolerability and exposure control important product attributes.[1]

When does pentoxifylline lose exclusivity?

Pentoxifylline’s fundamental U.S. composition and use exclusivity expired decades ago. The current commercial market is therefore genericized, and a new entrant generally cannot rely on molecule-level patent protection.

The original commercial opportunity was built around the extended-release dosage form. Any current exclusivity would need to arise from a later patent or regulatory protection covering a specific formulation, manufacturing process, delivery system, or new clinical use. Such protection would not block ordinary generic pentoxifylline products unless the generic product practiced the protected claims.

What is the Orange Book status of pentoxifylline?

The FDA Orange Book remains the controlling source for current U.S. reference-listed drug, patent, and exclusivity information. A commercial filing strategy should distinguish between:

• the reference-listed 400 mg extended-release product;
• approved ANDAs with therapeutic equivalence codes;
• any listed method-of-use patents;
• any formulation or product-by-process patents;
• any withdrawn or discontinued products that remain relevant to reference-product selection.

For an established product such as pentoxifylline, the likely market position is an ANDA-based generic field with no meaningful active molecule patent barrier. The absence of a fundamental patent barrier increases price competition and shifts value toward formulation quality, manufacturing efficiency, and market access.[2]

What excipients are suitable for pentoxifylline extended-release tablets?

Pentoxifylline is a small, crystalline, water-soluble active ingredient. The formulation challenge is controlling release over the intended dosing interval rather than improving basic solubility. Hydrophilic matrix systems are the most practical starting point.

Recommended excipient architecture

Formulation function	Candidate excipients	Commercial rationale
Hydrophilic release matrix	Hypromellose, particularly controlled-viscosity grades	Established, scalable, and available from multiple suppliers
Secondary release control	Ethylcellulose, cellulose acetate, or polymeric coating systems	Useful when matrix erosion alone does not provide sufficient control
Diluent	Microcrystalline cellulose, lactose, dibasic calcium phosphate	Supports compression, tablet strength, and cost control
Binder	Povidone, copovidone, pregelatinized starch	Improves granule strength and content uniformity
Glidant	Colloidal silicon dioxide	Improves flow and reduces manufacturing variability
Lubricant	Magnesium stearate or sodium stearyl fumarate	Supports tablet ejection; concentration must be controlled
Film coat	Hypromellose, polyvinyl alcohol, polyethylene glycol, titanium dioxide or approved colorants	Improves appearance, swallowability, and moisture protection
Pore former or osmotic modifier	Polyethylene glycol, low-molecular-weight sugars, salts	Adjusts water ingress and release rate
Moisture-control aid	High-barrier coating and desiccant packaging	Reduces dissolution drift during shelf life

A hydrophilic hypromellose matrix is commercially attractive because it avoids complex equipment and can be manufactured by direct compression or wet granulation. The primary development variables are polymer viscosity, polymer concentration, tablet hardness, porosity, granule size, and lubricant level.

A coated matrix tablet may provide better control where the active ingredient releases too quickly at early time points. It also creates more formulation variables that can support a differentiated patent filing, although it increases process complexity and regulatory comparability requirements.

What formulation patents could protect a pentoxifylline product?

A generic 400 mg extended-release tablet is unlikely to support strong patent protection merely because it uses a conventional matrix polymer. Patent value would require a defined technical result linked to a narrow composition or process.

Potential claim areas include:

1. Alcohol-resistant extended release. Claims could cover dissolution performance in hydroalcoholic media and a specific polymer combination that limits dose dumping.
2. pH-independent release. A composition that maintains a defined release profile across gastric and intestinal pH conditions may support formulation claims.
3. Low-dose excipient matrix. A high-drug-load tablet with reduced polymer content, lower tablet mass, or improved swallowability may have commercial value.
4. Manufacturing process. A granulation, coating, compression, or drying process that improves content uniformity or reduces dissolution variability could support process claims.
5. Stability composition. A formulation that limits degradation, discoloration, moisture uptake, or impurity formation may be patentable if the result is unexpected.
6. Multiparticulate delivery. Pellets, mini-tablets, or coated particles could provide differentiated release and flexibility in capsule or sachet formats.
7. Combination products. Combinations with other vascular or cardiovascular therapies could create method-of-use or fixed-dose opportunities, but clinical and regulatory requirements would be materially higher.

Broad claims covering “pentoxifylline in an extended-release tablet” would face substantial validity and obviousness risk because the dosage form is established. Narrow claims tied to quantitative dissolution limits, excipient ratios, or manufacturing conditions are more defensible but also easier to design around.

How should an excipient strategy address manufacturing and bioequivalence?

The central development objective is a dissolution profile that remains consistent across scale, equipment, and raw-material lots. Pentoxifylline’s commercial success depends on reproducible modified release rather than a novel pharmacology profile.

Critical quality attributes

The target product profile should control:

• assay and content uniformity;
• tablet hardness and friability;
• water activity and residual moisture;
• dissolution at multiple pH values;
• release after exposure to alcohol concentrations relevant to dose-dumping studies;
• impurity profile;
• stability under accelerated and long-term conditions;
• pharmacokinetic exposure, including Cmax and AUC.

A high-viscosity hypromellose grade can reduce burst release but may create incomplete release or excessive tablet swelling. A low-viscosity grade can improve manufacturability but may produce an overly rapid initial phase. Polymer particle size and substitution type can materially affect hydration and gel formation.

Lubrication requires particular control. Excess magnesium stearate can reduce wetting and slow or destabilize release. Under-lubrication can increase sticking, ejection force, and tablet defects. Changes in lactose grade, microcrystalline cellulose moisture, or compression force can also alter dissolution.

The development program should use a design-of-experiments approach covering polymer level, lubricant level, compression force, granulation endpoint, and coating weight gain. FDA modified-release guidance and SUPAC-MR principles make post-approval manufacturing changes more manageable when the formulation and process are well characterized.[3,4]

What commercial opportunities exist for pentoxifylline?

The largest opportunity is a low-cost, dependable generic product with broad pharmacy and wholesaler coverage. Pentoxifylline is unlikely to support premium pricing without a meaningful product advantage.

Attractive product concepts

1. High-quality generic 400 mg extended-release tablet

This is the lowest-risk opportunity. Commercial differentiation would come from:

• stable dissolution across lots;
• reliable supply;
• lower tablet defect rates;
• competitive cost of goods;
• multiple pack sizes;
• pharmacy-friendly blister or bottle packaging.

2. Once-daily or twice-daily modified-release product

The labeled regimen is generally 400 mg three times daily, with dose reduction when needed. A genuinely bioequivalent twice-daily or once-daily product could improve adherence, but it would likely require a new formulation and potentially a 505(b)(2) pathway rather than a conventional ANDA. Clinical exposure, tolerability, and total daily dose would require careful evaluation.[1]

3. Alcohol-resistant formulation

A formulation with controlled release in hydroalcoholic media could provide a defensible technical differentiator. This concept has broader value across modified-release products because dose dumping is a recognized regulatory concern.

4. Multiparticulate or sprinkle formulation

A capsule containing coated pellets or mini-tablets could address swallowing difficulties and offer a flexible release platform. The opportunity is commercially narrower because the existing product is a tablet and the new dosage form would carry additional development costs.

5. Emerging-market supply platform

Pentoxifylline may have commercial value in markets where peripheral arterial disease treatment remains price sensitive and generic supply is fragmented. A manufacturer with regional registration capability, local packaging, and dependable API sourcing could compete more effectively than a purely price-driven supplier.

Which companies are challenging pentoxifylline exclusivity?

The market is primarily challenged by generic manufacturers rather than by a single high-profile Paragraph IV campaign. Pentoxifylline has been available from multiple generic suppliers in the United States and internationally.

What Paragraph IV risks exist?

Paragraph IV litigation risk is low for the basic product because the core drug and established extended-release formulation are old. Risk could reappear if a sponsor obtains a later patent covering:

• a new release profile;
• an abuse-deterrent or alcohol-resistant formulation;
• a novel combination;
• a new dosing regimen;
• a multiparticulate system.

An ANDA applicant targeting a listed patent would need to evaluate Paragraph IV certification, patent litigation exposure, and possible 30-month stay implications under the Hatch-Waxman framework.[5]

What settlement agreements affect the market?

No major, market-defining pentoxifylline patent settlement is generally associated with the established generic market. Any commercial launch analysis should review current Orange Book listings, FDA approval dates, and litigation dockets rather than rely on historical reference-product exclusivity.

Is there biosimilar risk for pentoxifylline?

No. Pentoxifylline is a chemically synthesized small molecule, not a biologic. The relevant competitive risks are generic substitution, therapeutic alternatives, and reimbursement pressure.

Competitive products include other treatments for intermittent claudication, especially cilostazol, supervised exercise programs, antiplatelet therapy, lipid management, smoking cessation, and revascularization where clinically appropriate. Cilostazol is the principal pharmacologic comparator in the intermittent-claudication segment, although the two drugs have different contraindications, safety profiles, and clinical positioning.

How does pentoxifylline compare with cilostazol?

Factor	Pentoxifylline	Cilostazol
Drug class	Methylxanthine derivative	Phosphodiesterase 3 inhibitor
Common dosage form	400 mg extended-release tablet	50 mg or 100 mg tablet
Primary use	Intermittent claudication	Intermittent claudication
Generic status	Generic	Generic
Formulation opportunity	Extended-release matrix and multiparticulates	Immediate-release tablet and alternative delivery systems
Key commercial pressure	Low price and limited differentiation	Strong guideline and prescriber familiarity in some markets
Major safety constraint	Gastrointestinal and central nervous system adverse effects	Contraindicated in heart failure
Patent moat	Core protection expired	Core protection expired

Pentoxifylline can compete where tolerability, contraindications, formulary position, or physician preference favor it. It is unlikely to command a premium based solely on efficacy claims without new clinical evidence.

What geographic markets offer the best opportunity?

The United States offers a straightforward generic pathway but intense price competition. Europe and other highly regulated markets require country-specific or centralized regulatory work, with pricing controlled by reimbursement systems. Emerging markets may offer higher unit growth but present greater risks involving local registration, tender pricing, API qualification, and distributor concentration.

The most defensible international strategy is a common core formulation supported by region-specific packaging, stability data, language requirements, and registration documentation. A formulation that uses compendial excipients available from multiple qualified suppliers reduces supply-chain risk.

How strong is the patent estate for pentoxifylline?

The patent estate is weak at the molecule level and potentially moderate only for a genuinely novel delivery system. The commercial moat can be ranked as follows:

Protection type	Strength
Original active-ingredient patent	Expired
Original intermittent-claudication use	Expired or commercially ineffective
Conventional 400 mg matrix tablet	Weak
Defined alcohol-resistant formulation	Moderate if technically supported
Novel multiparticulate system	Moderate, depending on claims
Manufacturing process with demonstrated benefit	Narrow to moderate
New clinical use	Potentially meaningful, but clinically expensive
Brand and supply reliability	Commercial rather than legal protection

Licensing opportunities are therefore more likely to involve a formulation platform, regional commercialization rights, or contract manufacturing than a valuable pentoxifylline molecule license.

Key Takeaways

• Pentoxifylline is an established generic small molecule with no biosimilar exposure.
• The core patent position is expired, and conventional 400 mg extended-release tablets have limited patentability.
• A hypromellose-based matrix is the most practical excipient platform.
• The highest-value technical targets are dissolution reproducibility, alcohol resistance, stability, and low-cost scale-up.
• A novel twice-daily, once-daily, multiparticulate, or alcohol-resistant product could support a stronger commercial position.
• Standard generic entry is likely to face price competition and limited margin expansion.
• The best business cases combine reliable manufacturing with international registration, supply assurance, and targeted formulation differentiation.
• Current Orange Book listings and FDA approval data should control any live launch, patent, or litigation decision.[2]

FAQs About Pentoxifylline Excipient and Commercial Strategy

Can lactose be used in pentoxifylline extended-release tablets?

Yes. Lactose can function as a diluent, but its grade, moisture content, particle-size distribution, and interaction with the release polymer must be controlled because these variables can affect tablet porosity and dissolution.

Is hypromellose sufficient for a pentoxifylline sustained-release formulation?

Often, yes. Hypromellose can provide a scalable hydrophilic matrix, but polymer viscosity, concentration, tablet geometry, compression force, and drug loading determine whether the release profile is acceptable.

Could a pentoxifylline product qualify for a 505(b)(2) application?

Potentially, if the product introduces a materially different dosage form, dosing regimen, delivery system, or clinical use that cannot be supported through a conventional ANDA. A standard equivalent extended-release tablet would generally be better aligned with the ANDA pathway.

What is the main formulation failure mode for pentoxifylline?

The principal risks are excessive early release, dissolution drift between lots, incomplete release at later time points, and altered exposure after alcohol co-ingestion. Process variability can produce these outcomes even when the nominal composition is unchanged.

Is a pentoxifylline fixed-dose combination commercially attractive?

It is a higher-risk opportunity. A fixed-dose combination could improve adherence, but it would require compatibility data, clinical justification, dose selection, and a regulatory strategy that is more complex than a conventional generic pentoxifylline product.

References

1. U.S. Food and Drug Administration. (2023). Pentoxifylline extended-release tablets: Prescribing information. DailyMed.

2. U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations. Orange Book.

3. U.S. Food and Drug Administration. (1997). SUPAC-MR: Modified release solid oral dosage forms: Scale-up and postapproval changes. Center for Drug Evaluation and Research.

4. U.S. Food and Drug Administration. (2019). Extended release solid oral dosage forms: Development, evaluation, and application of in vitro/in vivo correlations. Center for Drug Evaluation and Research.

5. U.S. Congress. (1984). Drug Price Competition and Patent Term Restoration Act, Pub. L. No. 98-417.