Hydrochlorothiazide; triamterene - Generic Drug Details

What are the generic sources for hydrochlorothiazide; triamterene and what is the scope of freedom to operate?

Hydrochlorothiazide; triamterene is the generic ingredient in four branded drugs marketed by Glaxosmithkline Llc, Ani Pharms, Cadila, Chartwell Rx, Duramed Pharms Barr, Lannett Co Inc, Macleods Pharms Ltd, Novartis, Pharmobedient, Sandoz, Vitarine, Aurobindo Pharma Usa, Am Therap, Apotex Inc, Pliva, Quantum Pharmics, Rubicon Research, Watson Labs, and Zydus Pharms, and is included in twenty-five NDAs. Additional information is available in the individual branded drug profile pages.

Twenty-four suppliers are listed for this compound.

Summary for hydrochlorothiazide; triamterene

US Patents:	0
Tradenames:	4
Applicants:	19
NDAs:	25
Finished Product Suppliers / Packagers:	24
Raw Ingredient (Bulk) Api Vendors:	6
Clinical Trials:	5
DailyMed Link:	hydrochlorothiazide; triamterene at DailyMed

Recent Clinical Trials for hydrochlorothiazide; triamterene

Identify potential brand extensions & 505(b)(2) entrants

Sponsor	Phase
University of California, Irvine	Phase 4
West China Hospital	Phase 4
Vanderbilt University	N/A

See all hydrochlorothiazide; triamterene clinical trials

Pharmacology for hydrochlorothiazide; triamterene

Drug Class	Potassium-sparing Diuretic Thiazide Diuretic
Physiological Effect	Decreased Renal K+ Excretion Increased Diuresis

Anatomical Therapeutic Chemical (ATC) Classes for hydrochlorothiazide; triamterene

C03AA	Thiazides, plain
C03A	LOW-CEILING DIURETICS, THIAZIDES
C03	DIURETICS
C	Cardiovascular system

C03AA	Thiazides, plain
C03A	LOW-CEILING DIURETICS, THIAZIDES
C03	DIURETICS
C	Cardiovascular system

C03DB	Other potassium-sparing agents
C03D	ALDOSTERONE ANTAGONISTS AND OTHER POTASSIUM-SPARING AGENTS
C03	DIURETICS
C	Cardiovascular system

US Patents and Regulatory Information for hydrochlorothiazide; triamterene

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Apotex Inc	TRIAMTERENE AND HYDROCHLOROTHIAZIDE	hydrochlorothiazide; triamterene	TABLET;ORAL	071251-001	Apr 17, 1988	AB	RX	No	No
Rubicon Research	TRIAMTERENE AND HYDROCHLOROTHIAZIDE	hydrochlorothiazide; triamterene	TABLET;ORAL	216211-002	Feb 23, 2022	AB	RX	No	No
Pliva	TRIAMTERENE AND HYDROCHLOROTHIAZIDE	hydrochlorothiazide; triamterene	TABLET;ORAL	074026-001	Apr 26, 1996		DISCN	No	No

Expired US Patents for hydrochlorothiazide; triamterene

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	Patent No.	Patent Expiration
Aurobindo Pharma Usa	MAXZIDE	hydrochlorothiazide; triamterene	TABLET;ORAL	019129-001	Oct 22, 1984	4,105,783
Aurobindo Pharma Usa	MAXZIDE-25	hydrochlorothiazide; triamterene	TABLET;ORAL	019129-003	May 13, 1988	4,444,769
Aurobindo Pharma Usa	MAXZIDE	hydrochlorothiazide; triamterene	TABLET;ORAL	019129-001	Oct 22, 1984	4,444,769

Market Dynamics and Financial Trajectory for Hydrochlorothiazide; Triamterene

Last updated: July 27, 2025

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Introduction

Hydrochlorothiazide (HCTZ) combined with triamterene is a widely prescribed diuretic therapy for hypertension and edema management. This fixed-dose combination (FDC) offers synergistic effects, improving patient compliance and therapeutic outcomes. Understanding the market landscape and financial trajectory of this drug combination involves analyzing regulatory trends, patent statuses, competitive dynamics, clinical demand, and emerging innovations influencing its commercial viability.

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Regulatory and Patent Landscape

Hydrochlorothiazide and triamterene combination formulations have long-standing market presence, with many formulations now available as generics following patent expirations. HCTZ, introduced in the 1950s, experienced patent expiry decades ago, paving the way for a broad generic market. Similarly, triamterene's patent expiry facilitated compounding and off-patent formulations.

However, recent regulatory developments, including the U.S. Food and Drug Administration (FDA)’s initiatives encouraging generic drug use and compounding, continue to bolster market penetration. The absence of new patent protections for these formulations limits innovation but sustains high-volume manufacturing and sales driven by cost-sensitive markets globally.

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Market Drivers

1. Growing Hypertension Prevalence
Resilient in both developed and developing countries, hypertension afflicts over 1.3 billion people worldwide with projections indicating continued growth. The combination of HCTZ and triamterene remains a mainstay in hypertension management, especially for patients requiring potassium-sparing diuretics alongside thiazides, contributing to sustained demand.

2. Cost-Effectiveness of Generic Formulations
The availability of affordable, generic fixed-dose combinations sustains market access, particularly in regions with structured healthcare reimbursement systems that favor low-cost therapeutics. Manufacturers focus on maintaining extensive distribution channels to serve both outpatient clinics and hospitals.

3. Clinical Preference and Compliance
FDCs reduce pill burden, improve adherence, and mitigate the risk of electrolyte imbalances—attributes particularly valued in long-term hypertension management, fostering persistent clinical demand.

4. Off-Label and Adjunct Uses
Beyond hypertension, the combination finds off-label usage in conditions like heart failure and certain edematous states, albeit limited, contributing marginally to the overall market volume.

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Competitive and Market Challenges

1. Emergence of Alternative Therapies
Innovations in antihypertensive agents, including ACE inhibitors, ARBs, calcium channel blockers, and direct vasodilators, threaten the dominance of diuretic-based regimens. Additionally, single-pill combinations (SPCs) with other drug classes have entered the market, providing similar benefits with improved safety profiles.

2. Safety Concerns and Side Effect Profile
Electrolyte disturbances, including hyperkalemia associated with triamterene, pose safety considerations. As newer drugs demonstrate better safety profiles, they might replace diuretic combinations in certain patient subsets.

3. Regulatory and Reimbursement Policies
Price controls, reimbursement policies favoring most cost-effective treatments, and uncertainties regarding post-patent life metrics influence the financial trajectory. Some markets impose generic substitution policies, impacting brand sales.

4. Patent and Formulation Risks
While patent exclusivity has declined, certain formulations or extended-release versions may receive secondary patents or exclusivities, temporarily delaying generic entry and influencing market share.

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Market Size and Financial Trajectory

Global Market Scope
The global antihypertensive drugs market was valued at approximately USD 20 billion in 2022, with diuretics accounting for an estimated 10-15%. The HCTZ-triamterene combination, as a significant segment, saw consistent sales, particularly in the U.S. and Europe, with emerging markets reporting rapid growth due to increasing hypertension awareness and healthcare infrastructure expansion.

Growth Projections
Analysts project a compound annual growth rate (CAGR) of approximately 3-4% for the diuretic segment through 2027, driven predominantly by aging populations and chronic disease burden. The generic segment is expected to dominate, with sales stability maintained by high-volume, low-margin distribution.

Revenue Trends
Major generic pharmaceutical companies, such as Teva, Sandoz, and Mylan (now part of Viatris), continue to hold significant market share for HCTZ-triamterene tablets. Brand sales persist under specific marketed formulations, although their contribution diminishes over patent expiry.

Emerging Markets
The transition towards affordable therapeutic options in Asia-Pacific, Latin America, and Africa offers opportunity for growth in volume sales, albeit with pressure on prices. Local manufacturing and private-label distribution are prevalent strategies to penetrate these segments.

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Impact of Innovative and Alternative Therapies

The nutraceutical and digital health revolutions indirectly influence the prescription landscape. Digital tools enhance patient adherence, but innovations in drug delivery systems (e.g., sustained-release formulations) remain limited for this specific combination. Nonetheless, the trend towards personalized medicine may encourage future development of tailored antihypertensive regimens.

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Future Outlook and Trends

The financial trajectory for hydrochlorothiazide; triamterene will remain largely stable, buoyed by legacy market demand and cost-effective generics. However, growth rates are unlikely to accelerate significantly without new formulation innovations or favorable policy changes. The competitive landscape is expected to focus on price competition, formulation improvements, and integration with multi-drug regimens aimed at tackling resistant hypertension.

The integration of biosimilars and advanced pharmacogenomics may further dilute some traditional diuretic markets, indirectly influencing the share of HCTZ-triamterene formulations. As the healthcare environment emphasizes precision medicine, the role of generic diuretics may diminish in favor of newer, targeted therapies, constraining long-term growth potential but stabilizing incremental revenues through established markets.

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Key Takeaways

• Market stability for hydrochlorothiazide; triamterene hinges on the high prevalence of hypertension and the cost advantages of generics.
• Demand remains robust in emerging markets owing to economic factors and healthcare infrastructure expansion.
• Competitive pressures from newer antihypertensive classes and combination therapies challenge growth prospects.
• Patent expiries foster market saturation with generics, limiting significant revenue growth but providing stable cash flow.
• Innovation limited in this space; future growth relies on market expansion and regulatory policies favoring affordable generics.

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FAQs

1. Will the demand for hydrochlorothiazide; triamterene decline due to newer antihypertensive drugs?
While newer drugs offer improved safety profiles, the low-cost and proven efficacy of hydrochlorothiazide; triamterene maintain consistent demand, especially in cost-sensitive regions. However, prolonged use of innovative therapies may gradually supplant traditional diuretic combinations in some clinical settings.

2. How do patent expirations affect the financial outlook?
Patent expirations open the market to generics, leading to price erosion but increase sales volume through broader accessibility. For branded formulations, loss of exclusivity diminishes revenue, shifting focus toward cost-effective generic manufacturers.

3. What are the primary challenges facing the market for this drug combination?
Key challenges include competition from alternative antihypertensives, safety concerns related to electrolyte disturbances, regulatory pressures on drug pricing, and limited innovation.

4. Are there ongoing developments or formulations that could affect future sales?
Limited innovation exists; however, sustained-release versions or fixed-dose combinations with other classes could influence market dynamics marginally in the coming years.

5. Which regions present the most growth opportunities for hydrochlorothiazide; triamterene?
Emerging markets in Asia-Pacific, Latin America, and Africa offer significant growth opportunities due to increasing hypertension prevalence and demand for affordable treatment options.

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References

1. [1] World Health Organization. Hypertension Fact Sheet. 2022.
2. [2] FDA. Overview of Generic Drug Approvals. 2022.
3. [3] MarketWatch. Global Diuretics Market Report. 2022.
4. [4] IMS Health. Hypertension Medication Trends. 2022.
5. [5] EvaluatePharma. 2023. Pharmaceutical Market Forecasts.