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
Pliva	TRIAMTERENE AND HYDROCHLOROTHIAZIDE	hydrochlorothiazide; triamterene	TABLET;ORAL	074026-001	Apr 26, 1996		DISCN	No	No
Ani Pharms	TRIAMTERENE AND HYDROCHLOROTHIAZIDE	hydrochlorothiazide; triamterene	TABLET;ORAL	073467-001	Jan 31, 1996		DISCN	No	No
Lannett Co Inc	TRIAMTERENE AND HYDROCHLOROTHIAZIDE	hydrochlorothiazide; triamterene	CAPSULE;ORAL	201407-001	Dec 9, 2011	AB	RX	No	No
Glaxosmithkline Llc	DYAZIDE	hydrochlorothiazide; triamterene	CAPSULE;ORAL	016042-003	Mar 3, 1994		DISCN	Yes	No
Watson Labs	TRIAMTERENE AND HYDROCHLOROTHIAZIDE	hydrochlorothiazide; triamterene	TABLET;ORAL	071851-001	Nov 30, 1988	AB	RX	No	No
Vitarine	TRIAMTERENE AND HYDROCHLOROTHIAZIDE	hydrochlorothiazide; triamterene	CAPSULE;ORAL	071737-001	Feb 12, 1988		DISCN	No	No
Zydus Pharms	TRIAMTERENE AND HYDROCHLOROTHIAZIDE	hydrochlorothiazide; triamterene	TABLET;ORAL	208360-001	Jun 29, 2018	AB	RX	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	hydrochlorothiazide; triamterene	TABLET;ORAL	019129-001	Oct 22, 1984	4,444,769
Aurobindo Pharma Usa	MAXZIDE-25	hydrochlorothiazide; triamterene	TABLET;ORAL	019129-003	May 13, 1988	4,444,769

Summary

Last updated: February 13, 2026

Hydrochlorothiazide and triamterene are diuretics prescribed for hypertension and edema. Market demand is shaped by the prevalence of cardiovascular and renal diseases. The drugs are available as generic formulations, leading to price erosion but stable volume sales. Patent expiration and generic entry have significantly impacted market revenues. Regulatory approvals influence market growth, and the competitive landscape centers around manufacturing costs, drug efficacy, and safety profiles. Financial trajectories are characterized by declining margins for branded products and expanding opportunities in generics.

What Are the Market Fundamentals for Hydrochlorothiazide and Triamterene?

Hydrochlorothiazide (HCTZ) is a thiazide diuretic introduced in the 1950s, which remains among the most prescribed antihypertensive agents globally. Triamterene models potassium-sparing diuretics and is commonly combined with HCTZ to improve efficacy and mitigate side effects.

The drugs target essential hypertension, congestive heart failure, and edema. The global market size for diuretics was valued at approximately USD 3.2 billion in 2022. HCTZ accounts for around USD 2.5 billion of this figure, with triamterene comprising roughly USD 0.7 billion, primarily in combination formulations.

How Has Patent Expiry and Generic Competition Affected Market Dynamics?

Patent protection Granted for branded formulations of hydrochlorothiazide expired between 1995 and 2000, leading to widespread generics. Triamterene's patents, where applicable, expired around 2000-2005, allowing generic manufacturing.

The patent expirations caused a sharp decline in branded drug prices, by as much as 80% within two years of generic entry. As a result, brand-specific revenues declined from peak levels exceeding USD 1 billion annually in the late 1990s to less than USD 200 million today for some formulations.

Generic penetration exceeds 70% in most major markets. This volume-driven market means revenue margins for manufacturers rely heavily on low-cost production and distribution efficiency.

What Are the Key Regulatory and Policy Factors Impacting the Market?

Regulatory bodies such as the FDA in the U.S. and EMA in Europe have streamlined approval pathways for generics, facilitating market entry. Policies promoting cost-saving measures and generic substitution have increased the use of generic diuretics.

The introduction of biosimilar and authorized generic options further intensifies price competition. Regulatory challenges, such as biosimilar approval, are less relevant for small molecules like HCTZ and triamterene.

How Do Manufacturing and Pricing Strategies Shape Financial Outcomes?

Economies of scale dominate profitability for generic manufacturers. Suppliers focus on high-volume, low-cost production, often in emerging markets such as India and China, where manufacturing costs are 30-50% lower than in Western countries.

Pricing strategies involve aggressive discounting to secure market share, with price decreases reaching 20-40% annually post-generic entry. Despite declining prices, volume sales sustain revenues.

For branded formulations, revenue declines have prompted firms to diversify portfolios. Cost containment, including patent litigation and settlement agreements, plays a crucial role in maintaining profitability.

What Is the Future Outlook for Hydrochlorothiazide and Triamterene?

Market growth is capped by mature status; however, increased usage persists in regions with high hypertension prevalence. Developing markets exhibit potential for growth, driven by rising healthcare access and government-led public health initiatives.

Regulatory trends favor generic consolidation. The future revenue stream depends on manufacturing efficiencies and potential reformulations that improve safety profiles.

Innovation primarily relates to combination therapies. No significant pipeline products or reformulations are underway for HCTZ or triamterene themselves.

How Do Financial Trajectories Differ Between Developed and Developing Markets?

In developed markets, price pressures dominate, and margins are pressurized due to extensive generic competition. Revenues decline accordingly, with some companies choosing litigation or patent settlement pathways.

In emerging markets, volume drives revenues, with less intense price competition. Investment in local manufacturing and regulatory engagement fosters growth.

The global shift towards value-based care models favors cost-effective therapies, which benefits widespread use of inexpensive diuretics like HCTZ and triamterene.

Key Takeaways

• Patent expirations led to generic dominance, diminishing branded revenues.
• Market growth relies heavily on volume sales, especially in emerging markets.
• Price erosion for generics is significant, with declines up to 40% annually.
• Regulatory environments facilitate generic entry, increasing competition.
• Innovation is limited; future revenues depend on cost efficiencies and geographic expansion.

FAQs

1. What factors most influence the pricing of hydrochlorothiazide and triamterene?

Pricing is primarily influenced by patent status, competition levels, manufacturing costs, and regional regulatory policies. Once patents expire, generic competition drives prices down significantly.

2. Are there significant patent litigations or patent thickets affecting these drugs?

Most patents on HCTZ expired by 2000. Current patent litigation is limited to formulation patents or combination therapies; large patent thickets are not present.

3. What are the primary markets driving demand for these drugs?

The U.S., Europe, and Japan historically dominate demand, but emerging markets like India, China, and Brazil experience increasing usage due to higher hypertension prevalence and improved healthcare access.

4. How do regulatory approvals affect market entry for generics?

Streamlined approval pathways and bioequivalence requirements lower barriers, enabling rapid and cost-effective entry, which exerts downward pressure on prices and profit margins.

5. Will there be new formulations or combination therapies in the pipeline?

No significant reformulations or new combination therapies involving HCTZ or triamterene are currently under regulatory review; the market remains largely mature with minimal innovation.

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References

[1] IQVIA, "The Global Use of Medicines in 2022," IQVIA Institute.
[2] FDA, "Drug Approvals and Patent Expiries," FDA.gov.
[3] Market data, "Diuretics Global Market," ReportLinker, 2022.
[4] S. Williams et al., "Impact of Patent Expiry on Diuretic Market," Journal of Pharmaceutical Economics, 2021.