List of Excipients in Branded Drug TINDAZOLE

Generic Drugs Containing TINDAZOLE

Company	Ingredient	NDC	Excipient
Pack Pharmaceuticals LLC	tinidazole	16571-214	CELLULOSE, MICROCRYSTALLINE
Pack Pharmaceuticals LLC	tinidazole	16571-214	CROSCARMELLOSE SODIUM
Pack Pharmaceuticals LLC	tinidazole	16571-214	FD&C RED NO. 40
Pack Pharmaceuticals LLC	tinidazole	16571-214	FD&C YELLOW NO. 6
Pack Pharmaceuticals LLC	tinidazole	16571-214	HYPROMELLOSES
Pack Pharmaceuticals LLC	tinidazole	16571-214	MAGNESIUM STEARATE

What are the Most Frequently-Used Excipients in TINDAZOLE?

# Of NDCs	Excipient
4	CELLULOSE, MICROCRYSTALLINE
4	CROSCARMELLOSE SODIUM
4	FD&C RED NO. 40
4	FD&C YELLOW NO. 6
4	HYPROMELLOSES
4	MAGNESIUM STEARATE

Tinidazole Excipient Strategy and Commercial Opportunities

Last updated: September 24, 2026

Tinidazole is a generic nitroimidazole antimicrobial with established oral-tablet use and limited remaining differentiation at the active-ingredient level. The strongest commercial opportunities are in taste-masked pediatric products, rapid-dispersing oral dosage forms, lower-cost manufacturing, combination therapies, and region-specific formulations for parasitic and anaerobic infections. Core patent and regulatory exclusivity barriers are generally low in the United States, but formulation, process, and market-specific intellectual-property barriers may still affect product economics.

What is tinidazole and where is it used?

Tinidazole is a 5-nitroimidazole antimicrobial related to metronidazole. It is administered orally and has activity against selected anaerobic bacteria and protozoa.

Attribute	Tinidazole
Drug class	Nitroimidazole antimicrobial
Common dosage form	Immediate-release oral tablet
Common strengths	250 mg and 500 mg
FDA reference product	Tindamax
Original U.S. sponsor	Mission Pharmacal
Approved indications	Trichomoniasis, giardiasis, amebiasis, and bacterial vaginosis
Administration	Oral, often with food to reduce gastrointestinal discomfort
Main formulation challenges	Bitter taste, limited aqueous solubility, tablet disintegration, powder handling, and dose flexibility

The FDA labeling for Tindamax identifies oral tablets as the approved U.S. dosage form. Tinidazole is also marketed internationally in tablets, oral suspensions, granules, and other dosage forms, although approval status varies by jurisdiction (U.S. Food and Drug Administration, 2023a; DailyMed, 2023).

What excipients are used in tinidazole tablets?

The reference product uses conventional tablet excipients rather than a technically complex delivery platform. Public labeling identifies inactive ingredients including microcrystalline cellulose, pregelatinized starch, magnesium stearate, colloidal silicon dioxide, and other standard tablet-processing materials, depending on strength and market presentation.

Functional role of major excipient classes

Excipient class	Typical function in tinidazole tablets	Commercial relevance
Microcrystalline cellulose	Diluent and dry binder	Supports direct compression and tablet robustness
Pregelatinized starch	Binder and disintegrant	Improves compactibility and tablet breakup
Colloidal silicon dioxide	Glidant and moisture-management aid	Improves powder flow and blend uniformity
Magnesium stearate	Lubricant	Reduces ejection force during compression
Crospovidone or sodium starch glycolate	Superdisintegrant, where used	Supports faster disintegration
Povidone or copovidone	Binder	Useful in wet granulation and hardness control
Mannitol, sorbitol, or lactose	Diluent and mouthfeel modifier	Relevant to chewable, orally disintegrating, or pediatric products
Hypromellose or ethylcellulose	Film-forming or taste-masking polymer	Can reduce immediate bitterness and improve handling
Mineral or synthetic pigments	Colorant and product identification	Supports strength differentiation and branding

Exact excipient selection must be established through formulation development and regulatory comparison. The commercial objective is to preserve immediate release while improving palatability, manufacturability, stability, or patient usability.

What formulation problems create the best commercial opportunities?

How can excipients address tinidazole bitterness?

Tinidazole has a pronounced bitter taste. Bitterness is a material barrier for pediatric, geriatric, and dysphagia-friendly products. Conventional film coating can reduce exposure during swallowing but may not prevent bitterness after tablet breakage or dispersion.

The strongest taste-masking approaches include:

1. Polymer coating of tinidazole particles.
2. Ion-exchange resin complexes.
3. Lipid or wax-based microparticles.
4. pH-dependent polymer barriers.
5. Drug-loaded granules incorporated into a reconstitutable suspension.
6. Multiparticulate sachets with sweetener and flavor systems.

Taste masking must be tested against dose loading. Tinidazole requires a relatively high active dose compared with many pediatric drugs, which limits the amount of coating or resin that can be added without creating an impractical dosage form.

What excipients improve tinidazole dissolution?

Tinidazole formulation programs may use wetting agents, surfactants, hydrophilic polymers, or particle-size reduction to improve dissolution. Candidate excipients include sodium lauryl sulfate, poloxamers, polysorbates, povidone, copovidone, and hydroxypropyl cellulose.

A dissolution-enhancement strategy must avoid converting the product into a modified-release dosage form. For an immediate-release generic, the target is rapid and reproducible drug release under compendial and discriminatory dissolution conditions.

Potential approaches include:

• Micronized tinidazole with a hydrophilic carrier.
• Spray-dried dispersions using povidone or copovidone.
• Co-milled drug-excipient systems.
• Wet granulation with surfactant-containing binder solutions.
• Self-emulsifying or lipid-based systems for selected liquid products.

The preferred approach depends on the drug's particle-size distribution, polymorphic form, dose, and stability profile.

What excipients are suitable for pediatric tinidazole products?

A pediatric formulation is the clearest product-extension opportunity. The existing adult tablet does not provide convenient dose titration for children and may be difficult to swallow.

Oral suspension strategy

A ready-to-use or reconstitutable suspension could combine:

• A suspending agent such as xanthan gum, sodium carboxymethylcellulose, or microcrystalline cellulose and carboxymethylcellulose.
• A wetting agent to prevent floating and clumping.
• A buffer to control pH.
• A preservative system where required.
• A sweetener such as sucralose, sodium saccharin, or sucrose.
• A flavor system selected through sensory testing.
• A chelating agent such as disodium edetate where justified.
• Antimicrobial packaging and reconstitution controls.

Tinidazole suspension development faces three commercial constraints: high dose volume, sedimentation, and taste exposure after swallowing. A concentrated suspension can reduce administration volume but increases viscosity and palatability challenges.

Orally disintegrating tablet strategy

An orally disintegrating tablet could improve administration for patients who cannot swallow conventional tablets. Suitable excipient systems may include mannitol, crospovidone, low-substituted hydroxypropyl cellulose, microcrystalline cellulose, and flavoring agents.

The primary risks are tablet size, mechanical friability, and bitterness after rapid disintegration. A coated microparticle approach is more commercially defensible than simply adding sweetener to an unmasked tinidazole powder.

What formulations are protected by tinidazole patents?

Tinidazole's original active-ingredient protection is historical rather than a current commercial barrier in the United States. Tindamax was approved under NDA 21-618 in 2004, and the conventional oral-tablet market has had generic competition for years (U.S. Food and Drug Administration, 2004).

The relevant intellectual-property opportunities now arise mainly from:

• Taste-masked tinidazole particles.
• Pediatric suspensions and granules.
• Orally disintegrating tablets.
• Stable liquid formulations.
• Combination products.
• Novel manufacturing processes.
• Specific particle-size or polymorph controls.
• Packaging and reconstitution systems.
• New methods of use in jurisdictions where such claims remain available.

A formulation patent must contain meaningful technical limitations. Broad claims covering "tinidazole plus a pharmaceutically acceptable excipient" are vulnerable to validity and written-description challenges. Stronger claims would define measurable attributes such as dissolution performance, particle coating thickness, drug loading, sedimentation rate, redispersibility, moisture stability, or taste-reduction results.

When does tinidazole lose exclusivity?

Tinidazole has already lost U.S. market exclusivity for conventional oral tablets. The reference product's regulatory exclusivity and core patent position do not prevent ANDA-based generic competition.

Exclusivity category	Tinidazole status
New chemical entity exclusivity	Expired
Conventional oral-tablet patent barrier	No longer the principal U.S. barrier
Generic availability	Established
Pediatric exclusivity	No current broad market consequence identified
Biosimilar exclusivity	Not applicable
New formulation exclusivity	Possible only if a new qualifying product is approved
Orphan-drug exclusivity	Not applicable to the established indications

A new tinidazole formulation could qualify for separate regulatory protection only if it meets the applicable statutory requirements. A reformulated product does not automatically receive new chemical-entity protection.

What is the Orange Book status of tinidazole?

Tinidazole tablets have been listed in the FDA's Approved Drug Products with Therapeutic Equivalence Evaluations, commonly known as the Orange Book. The reference product is Tindamax, and generic tinidazole tablets have been approved through the ANDA pathway.

Orange Book relevance is concentrated in:

• Reference listed drug identification.
• Therapeutic-equivalence evaluations.
• Listed patents and exclusivity.
• Paragraph IV certification exposure for any remaining listed patent.
• Generic substitution and market-entry timing.

No biosimilar pathway applies because tinidazole is a small-molecule drug, not a biologic.

Which companies are challenging tinidazole patents?

Tinidazole's conventional-tablet market is already genericized, so the principal commercial issue is competition among generic manufacturers rather than active Paragraph IV litigation against a current core patent estate.

A Paragraph IV challenge would become relevant if a sponsor listed a new formulation patent for a later-developed product. Potential challengers could target:

• Claim breadth.
• Obviousness over metronidazole and existing tinidazole formulations.
• Written description and enablement.
• Bioequivalence methodology.
• Lack of unexpected taste-masking or dissolution results.
• Non-infringement based on different excipient systems.

There is no biosimilar litigation pathway for tinidazole. Litigation risk would arise from small-molecule patent claims, regulatory exclusivity, or commercial manufacturing disputes.

What generic launch risks exist for tinidazole?

The generic launch risk for standard tablets is high because:

• The active ingredient is mature.
• The formulation is technically conventional.
• Multiple manufacturers can produce immediate-release tablets.
• Prescribers recognize the molecule and indications.
• Substitution is available in many markets.
• Price competition can reduce margins.

The risk profile changes for differentiated dosage forms.

Product concept	Technical barrier	Regulatory complexity	Commercial attractiveness
Standard 500 mg tablet	Low	Low to moderate	Low to moderate
Scored 250 mg or 500 mg tablet	Low	Low to moderate	Moderate
Taste-masked pediatric suspension	Moderate to high	Moderate to high	High
Orally disintegrating tablet	Moderate	Moderate	Moderate to high
Sachet or granule formulation	Moderate	Moderate	Moderate
Modified-release product	High	High	Uncertain
Fixed-dose combination	High	High	Market dependent

How strong is the tinidazole patent estate?

The patent estate for legacy tinidazole tablets is weak as a source of market exclusivity because the product and dosage form are mature. A new patent estate could be commercially meaningful if it protects a differentiated formulation that solves a recognized administration problem.

Stronger patent claim categories

• Specific coated-particle structures.
• Defined excipient ratios.
• Controlled particle-size ranges.
• Dissolution profiles linked to formulation composition.
• Improved suspension stability.
• Reduced bitterness demonstrated by validated sensory or analytical methods.
• Improved bioavailability or reduced variability.
• Manufacturing steps that produce a distinct solid-state form.

Weaker patent claim categories

• Generic claims to conventional tablet excipients.
• Broad claims covering any oral tinidazole formulation.
• Formulations that merely substitute one common diluent for another.
• Claims unsupported by comparative data.
• Claims that do not distinguish over metronidazole formulation technology.

What licensing deals could support tinidazole commercialization?

Licensing opportunities are more likely to involve formulation technology than the tinidazole molecule. A company with a pediatric taste-masking platform could license the technology to a generic manufacturer or regional pharmaceutical company.

Potential transaction structures include:

• Regional licensing for pediatric suspension rights.
• Supply agreements for coated tinidazole microparticles.
• Co-development of a hospital-focused oral product.
• Technology licensing tied to manufacturing milestones.
• Royalty-bearing rights for a fixed-dose combination.
• Contract development and manufacturing arrangements.

The most attractive partner profile is a company with established anti-infective distribution, regulatory infrastructure, and access to pediatric or hospital channels.

How does tinidazole compare with metronidazole?

Factor	Tinidazole	Metronidazole
Dosing frequency	Often less frequent	Frequently multiple daily doses
Market maturity	Mature generic	Highly mature generic
Taste challenge	Significant	Significant
Formulation opportunity	Pediatric, suspension, ODT	Broader dosage-form competition
Brand differentiation	Limited	Limited in oral generic segment
Clinical positioning	Useful for selected protozoal and anaerobic infections	Broader overall use
Commercial strategy	Convenience and palatability	Cost, availability, and formulation breadth

Tinidazole can compete on dosing convenience in selected indications. It cannot generally compete with metronidazole on breadth of indications, manufacturer count, or formulation availability.

What geographic markets offer the best opportunity?

The most promising markets are those where:

• Pediatric parasitic disease burden is substantial.
• Tinidazole is approved but liquid formulations are limited.
• Local manufacturers lack advanced taste-masking capability.
• Hospital and community pharmacy channels are fragmented.
• Generic pricing remains commercially viable.
• Regulatory pathways permit abridged applications for established products.

The United States offers a mature generic market with limited opportunity for an undifferentiated tablet. Emerging markets may provide greater volume potential for suspension, granule, and dispersible products, but local registration, pharmacopoeial, labeling, preservative, and stability requirements must be addressed separately.

What commercial strategy is most attractive for tinidazole?

The strongest strategy is a differentiated oral product rather than another conventional tablet. Priority should be:

1. Pediatric taste-masked suspension or granules.
2. Low-volume reconstitutable suspension.
3. Orally disintegrating or dispersible tablet.
4. Scored tablet with flexible dosing.
5. Region-specific fixed-dose combination, where clinically and regulatorily justified.
6. Standard tablet manufactured at a lower cost only where supply reliability is a differentiator.

A formulation program should establish comparative dissolution, stability, microbial quality, dose uniformity, sedimentation, redispersibility, taste reduction, and bioequivalence. The formulation should also avoid unnecessary excipient complexity that increases regulatory and supply-chain risk.

Key Takeaways

• Tinidazole's conventional oral-tablet market is mature and genericized.
• Core molecule and legacy tablet patents provide limited current commercial protection.
• Bitterness and dose flexibility create the main formulation opportunities.
• Pediatric suspensions, granules, and orally disintegrating tablets offer the clearest differentiation.
• Excipient selection should prioritize taste masking, rapid dispersion, dose uniformity, and stability.
• New patent value will depend on measurable formulation performance, not generic excipient combinations.
• Tinidazole is not subject to biosimilar competition.
• Metronidazole remains the broader competitive benchmark, while tinidazole can differentiate through dosing convenience.
• Commercial returns are more likely from formulation technology, regional licensing, and pediatric delivery than from another standard tablet.

FAQs

Can tinidazole be formulated as a pediatric oral suspension?

Yes. A pediatric suspension can use suspending polymers, wetting agents, sweeteners, flavors, buffers, and taste-masked drug particles. The principal development issues are bitterness, high dose volume, sedimentation, and redispersibility.

Which excipient is best for masking tinidazole taste?

No single excipient is universally optimal. Polymer-coated particles, ion-exchange resins, lipid barriers, and multiparticulate granules are stronger starting points than sweeteners alone because tinidazole has a substantial bitter taste and may be administered at a high dose.

Is tinidazole eligible for biosimilar development?

No. Tinidazole is a synthetic small-molecule drug. Follow-on products use generic-drug pathways such as ANDA approval or applicable non-U.S. abbreviated procedures.

Does a new tinidazole formulation receive new patent protection?

It can, if the formulation is novel, non-obvious, adequately described, and supported by technical data. A new dosage form does not automatically receive patent protection or regulatory exclusivity.

What is the highest-value tinidazole product opportunity?

A stable, low-volume, taste-masked pediatric suspension or granule product has the strongest differentiation potential. It addresses a recognized administration problem and is less exposed to direct price competition than a conventional immediate-release tablet.

References

1. DailyMed. (2023). Tindamax: Tinidazole tablet, film coated prescribing information. U.S. National Library of Medicine.

2. U.S. Food and Drug Administration. (2004). Tindamax approval letter and prescribing information, NDA 21-618. Center for Drug Evaluation and Research.

3. U.S. Food and Drug Administration. (2023a). Tinidazole prescribing information. Center for Drug Evaluation and Research.

4. U.S. Food and Drug Administration. (2023b). Approved drug products with therapeutic equivalence evaluations. Center for Drug Evaluation and Research.

5. United States Pharmacopeia. (2023). Tinidazole monograph and general chapters. United States Pharmacopeial Convention.