List of Excipients in Branded Drug INDAPAMIDE

« Back to Dashboard

Generic Drugs Containing INDAPAMIDE

Company	Ingredient	NDC	Excipient
Actavis Pharma Inc	indapamide	0228-2597	CELLULOSE, MICROCRYSTALLINE
Actavis Pharma Inc	indapamide	0228-2597	FD&C YELLOW NO. 6
Actavis Pharma Inc	indapamide	0228-2597	HYPROMELLOSES
Actavis Pharma Inc	indapamide	0228-2597	LACTOSE MONOHYDRATE
Actavis Pharma Inc	indapamide	0228-2597	MAGNESIUM STEARATE
Actavis Pharma Inc	indapamide	0228-2597	MALTODEXTRIN

What are the Most Frequently-Used Excipients in INDAPAMIDE?

# Of NDCs	Excipient
4	ANHYDROUS LACTOSE
17	CELLULOSE, MICROCRYSTALLINE
2	CI 77891
4	D&C RED NO. 30
8	FD&C YELLOW NO. 6
2	HYDROXYPROPYL METHYLCELLULOSE

Last updated: September 26, 2026

Executive summary: Indapamide is a mature, generic small-molecule diuretic with limited opportunity in basic immediate-release tablets and greater opportunity in differentiated modified-release, low-dose, fixed-dose combination, and market-specific formulations. The principal formulation challenge is controlling dissolution for a poorly water-soluble active ingredient while maintaining dose uniformity at 1.25 mg to 2.5 mg strengths. Excipient value is concentrated in particle engineering, wetting and solubilization, matrix release control, and robustness against food, compression, humidity, and scale-up effects. Core compound patents and regulatory exclusivity have expired, so commercial barriers depend mainly on formulation know-how, regulatory execution, manufacturing cost, and distribution.

Indapamide Excipient Strategy and Commercial Opportunities

What is indapamide and how is it used?

Indapamide is an oral sulfonamide-derived, thiazide-like diuretic used primarily for hypertension and, in some markets, edema associated with congestive heart failure. It reduces sodium and chloride reabsorption in the distal nephron and has additional vascular effects at antihypertensive doses.

Common dosage forms are:

Product type	Typical strength	Release profile	Primary commercial use
Immediate-release tablet	1.25 mg, 2.5 mg	Conventional	Hypertension
Higher-strength tablet	5 mg	Conventional	Less common; market-specific
Sustained-release tablet	1.5 mg	Modified release	Once-daily hypertension
Combination tablet	Varies	Immediate or modified release	Hypertension adherence and treatment intensification

Indapamide has low aqueous solubility, creating formulation sensitivity around wetting, particle size, dissolution, and excipient compatibility. The low dose also increases the importance of blend uniformity and segregation control.

The original branded product, Lozol, was approved in the United States in 1983. Current U.S. supply is predominantly generic, while modified-release products such as Natrilix SR and equivalent products have had stronger commercial relevance in Europe and other international markets.[1,2]

Which excipients are most important for indapamide tablets?

The optimal excipient platform depends on whether the product is immediate release or sustained release. No single excipient system applies to all indapamide products because composition, manufacturing process, target dissolution profile, and jurisdictional regulatory history differ.

Immediate-release excipient strategy

An immediate-release tablet generally requires:

• A diluent to support low-dose content uniformity
• A disintegrant to promote rapid tablet breakup
• A binder to support granule or tablet strength
• A glidant to improve powder flow
• A lubricant to control ejection and tooling friction
• A wetting or solubilizing aid where dissolution is inadequate

Typical candidate excipients include lactose monohydrate, microcrystalline cellulose, anhydrous dibasic calcium phosphate, pregelatinized starch, maize starch, crospovidone, croscarmellose sodium, sodium starch glycolate, povidone, colloidal silicon dioxide, and magnesium stearate.

A lactose-based direct-compression system can offer low cost and broad supplier availability. Microcrystalline cellulose can improve compactability and disintegration, but excessive levels may increase tablet porosity and alter dissolution. Starch-based systems can support disintegration but may introduce variability with moisture and source grade.

For a 1.25 mg dose, geometric dilution, ordered mixing, or roller compaction with controlled particle-size fractions may be more important than the choice between common filler systems. Magnesium stearate concentration and blending time require control because over-lubrication can reduce wettability and slow dissolution.

Modified-release excipient strategy

The 1.5 mg sustained-release product is the most attractive formulation segment because release control creates a higher technical barrier than a conventional tablet. Potential matrix systems include:

• Hydroxypropyl methylcellulose, particularly medium- and high-viscosity grades
• Hydroxypropyl cellulose
• Polyethylene oxide
• Carbomers
• Ethylcellulose or other insoluble release-controlling polymers
• Hydrophilic-lipophilic polymer combinations

A hydrophilic matrix can create a hydrated gel layer that controls diffusion and erosion. Polymer viscosity, particle size, concentration, compression force, and tablet surface area determine the release rate. Because indapamide is administered at a low dose, the matrix may contain a high proportion of excipient relative to active ingredient. That increases the effect of polymer variability on dissolution.

A multiparticulate approach using coated pellets or granules can provide tighter release control and reduce sensitivity to tablet dimensions. It also increases manufacturing complexity and may require capsule filling or compression of coated particles.

Solubilization and wetting options

Indapamide's low solubility may justify screening of:

• Sodium lauryl sulfate at low concentrations
• Poloxamers
• Polyethylene glycol derivatives
• Povidone or copovidone
• Surfactant-containing granulation systems
• Amorphous solid dispersions
• Cyclodextrin-based systems
• Co-milled or micronized active ingredient

Surfactants can improve dissolution but may create stability, taste, gastrointestinal tolerability, or scale-up issues. Amorphous systems can increase apparent solubility but introduce recrystallization risk. For a mature generic product, conventional particle-size control and wetting optimization are usually commercially preferable to a complex solid-dispersion platform unless the target market rewards improved bioavailability or a differentiated release profile.

What excipient risks affect indapamide product development?

The main risks are dissolution failure, content-uniformity failure, lubricant sensitivity, and stability drift.

Risk	Root cause	Commercial consequence	Control strategy
Slow dissolution	Poor wetting, excessive lubrication, high-compression tablet	Bioequivalence failure or delayed onset	Particle-size control, disintegrant optimization, surfactant screening
Content nonuniformity	Low dose, segregation, poor blending	Batch rejection or regulatory deficiency	Ordered mixing, validated blend sampling, density matching
Release variability	Polymer grade or viscosity variation	Modified-release failure	Tight polymer specifications and discriminatory dissolution testing
Tablet capping	Excess fines, poor granulation, high compression	Manufacturing yield loss	Granulation and compression optimization
Moisture instability	Hygroscopic excipients or API interaction	Assay or dissolution drift	Low-moisture processing, desiccant packaging, humidity studies
Over-lubrication	Excess magnesium stearate or prolonged blending	Lower dissolution and weaker release control	Defined lubricant addition and blend-time limits
API recrystallization	Amorphous or high-energy particle state	Loss of dissolution advantage	Solid-state characterization and accelerated stability testing

Indapamide should be evaluated for compatibility with lactose, reducing sugars, alkaline excipients, surfactants, and high-moisture processing conditions. Differential scanning calorimetry, powder X-ray diffraction, thermogravimetric analysis, infrared spectroscopy, and stress stability studies can identify physical and chemical interactions before scale-up.

What formulations are commercially protected for indapamide?

The strongest formulation differentiation is likely to arise from:

1. Sustained-release tablets with a reproducible once-daily profile.
2. Low-dose tablets with superior content uniformity.
3. Fixed-dose combinations with angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, or calcium-channel blockers.
4. Orally disintegrating or dispersible tablets for patients with swallowing difficulty.
5. Sprinkle or multiparticulate products for patients unable to swallow tablets.
6. Blister-packaged products with moisture protection for hot and humid markets.
7. Products optimized for low-cost high-volume manufacturing.

The technical value of an excipient strategy depends on whether it creates a measurable regulatory distinction. A simple substitution of lactose for microcrystalline cellulose generally has limited defensibility. A validated modified-release matrix, a novel multiparticulate system, or a clinically relevant dissolution and bioequivalence advantage has greater commercial value.

When did indapamide lose exclusivity?

Indapamide's original U.S. small-molecule exclusivity and core patent protection expired many years ago. The original U.S. NDA for Lozol dates to 1983, and multiple generic products have been marketed for decades.[1,3]

There is no biosimilar pathway for indapamide because it is a chemically synthesized small molecule. Commercial entry is governed by the abbreviated new drug application pathway in the United States, subject to applicable patent certifications and regulatory requirements.

The main remaining intellectual-property opportunities are secondary rights covering:

• Modified-release architecture
• Specific polymer combinations
• Particle-size or solid-state forms
• Manufacturing processes
• Fixed-dose combinations
• New dosage forms
• Pediatric or adherence-focused delivery systems
• Method-of-use claims tied to defined patient populations

A formulation patent must provide more than a routine excipient substitution. Patent strength improves when the claimed composition produces an unexpected dissolution profile, stability benefit, bioavailability result, manufacturing advantage, or clinical effect.

What is the Orange Book status of indapamide?

The FDA Orange Book identifies approved drug products and, where applicable, listed patents and exclusivity information.[3] Indapamide is an established generic product category with no biosimilar issue and no expected protection from original compound exclusivity.

For product developers, the relevant Orange Book questions are:

• Whether the selected reference listed drug remains the applicable reference product
• Whether the target strength and dosage form have an approved reference
• Whether any listed patent applies to the intended product
• Whether a Paragraph IV certification is required
• Whether a modified-release product has the same reference framework as an immediate-release tablet

Patent status must be assessed at the product and dosage-form level. A generic immediate-release tablet does not automatically establish a pathway for a modified-release tablet, and an international sustained-release product does not automatically determine U.S. reference-product status.

Are Paragraph IV challenges relevant to indapamide?

Paragraph IV activity is more relevant to later-generation modified-release or combination products than to the original immediate-release indapamide tablet. A generic applicant may use an ANDA with a Paragraph IV certification when it seeks approval before expiration of a listed patent that it asserts is invalid, unenforceable, or not infringed.

For legacy immediate-release indapamide, the practical risk is limited because the core product has been generic for many years. For a newly developed sustained-release or combination product, the principal challenge would involve listed formulation, method-of-use, or combination patents rather than the active ingredient itself.

A 30-month stay can arise when a patent owner or exclusive licensee files an infringement action within the statutory period after receiving a Paragraph IV notice. The commercial effect depends on the patent's scope, litigation timing, settlement terms, and the applicant's ability to launch at risk.

What patent litigation and settlement risks affect indapamide?

Indapamide has a low current litigation profile compared with newer cardiovascular drugs. The likely dispute areas are:

• Bioequivalence of modified-release products
• Scope of formulation claims
• Infringement of polymer-matrix patents
• Validity of solid-state or particle-size claims
• Fixed-dose combination patents
• Manufacturing-process claims

Settlement agreements could establish an agreed generic launch date, license rights, or restrictions on product scope. For a mature product, litigation economics are usually unfavorable unless the formulation has substantial market share or a specialized delivery platform supports premium pricing.

No broad biosimilar litigation risk exists because indapamide is not a biologic.

How does indapamide compare with other antihypertensive opportunities?

Attribute	Indapamide	Hydrochlorothiazide	Chlorthalidone	Amlodipine
Chemical type	Thiazide-like sulfonamide	Thiazide diuretic	Thiazide-like diuretic	Calcium-channel blocker
Generic maturity	High	High	High	High
Formulation difficulty	Moderate to high at low dose and in SR products	Moderate	Moderate	Moderate
Modified-release opportunity	Meaningful	Limited to moderate	Limited	Limited
Combination opportunity	High	High	Moderate	High
Excipient differentiation	Matrix control, dissolution, low-dose uniformity	Conventional tableting	Dose uniformity and dissolution	Stability, dissolution, combination compatibility
Biosimilar risk	None	None	None	None
Premium pricing potential	Low for IR; higher for differentiated SR	Low	Low to moderate	Low to moderate

Indapamide can compete with hydrochlorothiazide where once-daily use, sustained exposure, or a lower-dose thiazide-like profile is valued. Chlorthalidone has a longer duration of action, while indapamide may offer a more attractive formulation platform for controlled release and combination products.

What commercial opportunities exist for indapamide?

Generic immediate-release tablets

This is the lowest-risk but most price-sensitive segment. Success depends on manufacturing efficiency, reliable API supply, low defect rates, and broad pharmacy or hospital contracting. Excipient innovation has limited pricing power unless it reduces cost or improves manufacturing robustness.

Sustained-release tablets

The sustained-release segment offers the strongest formulation opportunity. A product with controlled dissolution, robust bioequivalence, and a compact tablet could support differentiated positioning in markets where once-daily cardiovascular therapy is emphasized.

Fixed-dose combinations

Indapamide combinations with perindopril have established market precedent in Europe and other regions. Combination products can improve adherence and create a higher-value regulatory product than an isolated generic tablet. The primary technical issues are API compatibility, dose proportionality, dissolution of both actives, and stability across different pH conditions.

Potential combination partners include:

• Perindopril
• Amlodipine
• Angiotensin receptor blockers
• Other antihypertensive agents selected for market-specific treatment guidelines

Patient-centric dosage forms

Orally disintegrating, dispersible, mini-tablet, and sprinkle formulations may address dysphagia, geriatric use, and institutional care. These products require careful control of taste, mouthfeel, dose uniformity, moisture protection, and packaging. Commercial value is higher where the product has a clear patient-use advantage and limited direct competition.

Emerging-market supply

India, Latin America, Southeast Asia, the Middle East, and parts of Africa offer volume opportunities for low-cost indapamide products. The main requirements are:

• Heat- and humidity-resistant packaging
• Robust tablet hardness and friability
• Simple, widely available excipients
• Reliable API sourcing
• Local registration and bioequivalence compliance
• Competitive tender pricing

For these markets, alu-alu blister packaging or high-barrier PVC/PVdC systems may be more valuable than complex excipient technology.

How strong is the indapamide patent estate?

The core indapamide patent estate is weak for exclusivity purposes because the active ingredient and original products are long established. The strongest potential rights are secondary patents tied to a specific formulation or combination.

Patent category	Current strategic strength	Commercial relevance
Original compound patents	Low or expired	No meaningful barrier to generic entry
Immediate-release tablet composition	Low	Limited differentiation
Sustained-release matrix	Moderate if technically narrow and validated	Potential launch barrier
Fixed-dose combination	Moderate, depending on claim scope	Adherence and lifecycle management
Particle-size or solid-state claims	Variable	Useful if linked to dissolution or stability
Manufacturing process	Variable	Can support know-how but is difficult to detect in finished products
Method of treatment	Moderate in selected jurisdictions	Often weaker against generic substitution
Packaging and stability	Low to moderate	More useful as know-how than as broad exclusivity

Trade secrets may be more important than patents for blend order, granulation endpoint, polymer grade selection, coating parameters, and compression settings. These controls can improve yield and bioequivalence without creating a publicly visible barrier.

What generic launch scenarios exist for indapamide?

The likely scenarios are:

1. Immediate-release generic entry with aggressive pricing and minimal differentiation.
2. Modified-release entry using a conventional hydrophilic matrix.
3. Combination-product launch focused on adherence and guideline-based therapy.
4. Local-market launch using low-cost excipients and high-barrier packaging.
5. Specialty dosage-form launch for dysphagia or institutional use.

Revenue exposure for incumbent manufacturers is concentrated in sustained-release and fixed-dose combination products rather than basic immediate-release tablets. A new entrant should avoid relying on patent exclusivity and instead compete through manufacturing cost, regulatory speed, distribution, supply reliability, or a clinically useful dosage form.

Key Takeaways

• Indapamide is a mature generic small molecule with no biosimilar risk.
• Immediate-release tablets are technically manageable but highly price competitive.
• Sustained-release products offer the clearest excipient-led differentiation.
• Low dose and low aqueous solubility make content uniformity and dissolution central development risks.
• Hydrophilic polymers, controlled particle size, wetting agents, and disciplined lubrication are the main formulation levers.
• Fixed-dose combinations and patient-centric dosage forms provide stronger commercial opportunities than a standard tablet.
• Core compound exclusivity has expired; secondary formulation and combination rights determine any remaining patent value.
• Manufacturing know-how, packaging, and supply reliability may provide more practical protection than broad patent claims.

FAQs

Can indapamide be formulated as an orally disintegrating tablet?

Yes. An orally disintegrating indapamide tablet would require low-dose content-uniformity controls, taste management, rapid wetting, adequate mechanical strength, and moisture-protective packaging.

Which excipient is best for sustained-release indapamide?

Hydroxypropyl methylcellulose is a practical starting point for a hydrophilic matrix, but the optimal grade and concentration depend on the target dissolution profile, tablet dimensions, compression force, and API particle characteristics.

Does indapamide require a solubilizer?

Not necessarily. Conventional particle-size reduction, wetting optimization, and disintegrant selection may be sufficient. A solubilizer becomes more attractive when dissolution remains inadequate after controlling particle size and tablet structure.

Can indapamide and perindopril be combined in one tablet?

Yes. Indapamide-perindopril fixed-dose products are established in several markets. Development requires compatibility testing, dual-API dissolution control, stability assessment, and an applicable regulatory bridge to the reference product.

Is a new indapamide formulation likely to receive premium pricing?

A conventional immediate-release formulation is unlikely to command a significant premium. Pricing potential is stronger for sustained release, fixed-dose combinations, dispersible products, or formulations with a documented adherence, stability, or manufacturing advantage.

References

1. U.S. Food and Drug Administration. (1983). Lozol (indapamide) tablets prescribing information. FDA Drugs@FDA database.

2. European Medicines Agency. (n.d.). Indapamide-containing medicinal products and product information. European Union medicines database.

3. U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations: The Orange Book. FDA.

4. National Library of Medicine. (n.d.). Indapamide. PubChem Compound Database.

5. United States Pharmacopeia. (2024). Indapamide monograph. USP-NF.