CLINICAL TRIALS PROFILE FOR LOSARTAN POTASSIUM AND HYDROCHLOROTHIAZIDE

All Clinical Trials for LOSARTAN POTASSIUM AND HYDROCHLOROTHIAZIDE

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00157963 ↗	Hydrochlorothiazide (+) Losartan Potassium vs. Amlodipine Comparative Study (0954A-314)	Completed	Merck Sharp & Dohme Corp.	Phase 4	2005-02-05	An efficacy and safety study of hydrochlorothiazide (+) losartan potassium compared to amlodipine at week 12 in Korean patients with essential hypertension
NCT00223717 ↗	Treatment of Supine Hypertension in Autonomic Failure	Completed	Vanderbilt University	Phase 1	2001-01-01	Supine hypertension is a common problem that affects at least 50% of patients with primary autonomic failure. Supine hypertension can be severe, and complicates the treatment of orthostatic hypotension. Drugs used for the treatment of orthostatic hypotension (eg, fludrocortisone and pressor agents), worsen supine hypertension. High blood pressure may also cause target organ damage in this group of patients. The pathophysiologic mechanisms causing supine hypertension in patients with autonomic failure have not been defined. In a study, we, the investigators at Vanderbilt University, examined 64 patients with AF, 29 with pure autonomic failure (PAF) and 35 with multiple system atrophy (MSA). 66% of patients had supine systolic (systolic blood pressure [SBP] > 150 mmHg) or diastolic (diastolic blood pressure [DBP] > 90 mmHg) hypertension (average blood pressure [BP]: 179 ± 5/89 ± 3 mmHg in 21 PAF and 175 ± 5/92 ± 3 mmHg in 21 MSA patients). Plasma norepinephrine (92 ± 15 pg/mL) and plasma renin activity (0.3 ± 0.05 ng/mL per hour) were very low in a subset of patients with AF and supine hypertension. (Shannon et al., 1997). Our group has showed that a residual sympathetic function contributes to supine hypertension in patients with severe autonomic failure and that this effect is more prominent in patients with MSA than in those with PAF (Shannon et al., 2000). MSA patients had a marked depressor response to low infusion rates of trimethaphan, a ganglionic blocker; the response in PAF patients was more variable. At 1 mg/min, trimethaphan decreased supine SBP by 67 +/- 8 and 12 +/- 6 mmHg in MSA and PAF patients, respectively (P < 0.0001). MSA patients with supine hypertension also had greater SBP response to oral yohimbine, a central alpha2 receptor blocker, than PAF patients. Plasma norepinephrine decreased in both groups, but heart rate did not change in either group. This result suggests that residual sympathetic activity drives supine hypertension in MSA; in contrast, supine hypertension in PAF. It is hoped that from this study will emerge a complete picture of the supine hypertension of autonomic failure. Understanding the mechanism of this paradoxical hypertension in the setting of profound loss of sympathetic function will improve our approach to the treatment of hypertension in autonomic failure, and it could also contribute to our understanding of hypertension in general.
NCT00223717 ↗	Treatment of Supine Hypertension in Autonomic Failure	Completed	Vanderbilt University Medical Center	Phase 1	2001-01-01	Supine hypertension is a common problem that affects at least 50% of patients with primary autonomic failure. Supine hypertension can be severe, and complicates the treatment of orthostatic hypotension. Drugs used for the treatment of orthostatic hypotension (eg, fludrocortisone and pressor agents), worsen supine hypertension. High blood pressure may also cause target organ damage in this group of patients. The pathophysiologic mechanisms causing supine hypertension in patients with autonomic failure have not been defined. In a study, we, the investigators at Vanderbilt University, examined 64 patients with AF, 29 with pure autonomic failure (PAF) and 35 with multiple system atrophy (MSA). 66% of patients had supine systolic (systolic blood pressure [SBP] > 150 mmHg) or diastolic (diastolic blood pressure [DBP] > 90 mmHg) hypertension (average blood pressure [BP]: 179 ± 5/89 ± 3 mmHg in 21 PAF and 175 ± 5/92 ± 3 mmHg in 21 MSA patients). Plasma norepinephrine (92 ± 15 pg/mL) and plasma renin activity (0.3 ± 0.05 ng/mL per hour) were very low in a subset of patients with AF and supine hypertension. (Shannon et al., 1997). Our group has showed that a residual sympathetic function contributes to supine hypertension in patients with severe autonomic failure and that this effect is more prominent in patients with MSA than in those with PAF (Shannon et al., 2000). MSA patients had a marked depressor response to low infusion rates of trimethaphan, a ganglionic blocker; the response in PAF patients was more variable. At 1 mg/min, trimethaphan decreased supine SBP by 67 +/- 8 and 12 +/- 6 mmHg in MSA and PAF patients, respectively (P < 0.0001). MSA patients with supine hypertension also had greater SBP response to oral yohimbine, a central alpha2 receptor blocker, than PAF patients. Plasma norepinephrine decreased in both groups, but heart rate did not change in either group. This result suggests that residual sympathetic activity drives supine hypertension in MSA; in contrast, supine hypertension in PAF. It is hoped that from this study will emerge a complete picture of the supine hypertension of autonomic failure. Understanding the mechanism of this paradoxical hypertension in the setting of profound loss of sympathetic function will improve our approach to the treatment of hypertension in autonomic failure, and it could also contribute to our understanding of hypertension in general.
NCT00289887 ↗	Obese Hypertension Study (0954-315)	Completed	Merck Sharp & Dohme Corp.	Phase 3	2006-02-01	This is a 16-week study to evaluate high systolic and diastolic blood pressure following treatment in obese, hypertensive, adult patients.
NCT00408512 ↗	Pharmacosurveillance and Pharmacogenetics of First-line Diuretics in Hypertension: The StayOnDiur Study	Completed	Agenzia Italiana del Farmaco	Phase 4	2006-12-01	Background: The use of thiazide diuretics in the treatment of hypertension (HT) is widely considered a first line treatment, given the efficacy and low cost of this class of drugs. This indication is not unanimous, because thiazides can cause metabolic alterations and other side effects increasing cardiac and cerebrovascular risk, which reduce compliance to treatment and increase health care system cost. However, large intervention trials in HT suggest that the improvement in cardiovascular prognosis of HT patients depends more on follow-up procedures than on type of drug used. Furthermore, the investigators have documented improved compliance to antihypertensive therapy by implementing cooperation between general practitioners (GPs) and HT specialists. Objectives: In a multicenter, open label randomized study the investigators will compare the persistence on therapy of thiazides versus other treatments, as a first line antihypertensive therapy, in a clinical setting characterized by a strict cooperation between GPs and HT specialist. The investigators will also analyse candidate genes with impact on drug-induced metabolic alterations to elucidate the pathophysiology of these phenomena. Methods: 260 GPs will recruit 2600 hypertensive patients with indication to pharmacological treatment and randomise them to starting treatment with chlortalidone (12.5 to 25 mg daily, 1300 pts) or a GP decided single drug (excluding thiazides) or combination therapy at highest tolerated dose. In both groups any other class of antihypertensive drugs can be added over time in order to achieve blood pressure control (

Clinical Trial Conditions for LOSARTAN POTASSIUM AND HYDROCHLOROTHIAZIDE

Condition Name

Condition Name for LOSARTAN POTASSIUM AND HYDROCHLOROTHIAZIDE
Intervention	Trials
Hypertension	9
Healthy	4
Essential Hypertension	2

Condition MeSH

Condition MeSH for LOSARTAN POTASSIUM AND HYDROCHLOROTHIAZIDE
Intervention	Trials
Hypertension	10
Essential Hypertension	5
Malnutrition	2
Pure Autonomic Failure	1

Clinical Trial Locations for LOSARTAN POTASSIUM AND HYDROCHLOROTHIAZIDE

Trials by Country

Trials by Country for LOSARTAN POTASSIUM AND HYDROCHLOROTHIAZIDE
Location	Trials
United States	5
China	1
India	1
Japan	1
Italy	1

Trials by US State

Trials by US State for LOSARTAN POTASSIUM AND HYDROCHLOROTHIAZIDE
Location	Trials
North Dakota	2
Texas	2
Tennessee	1

Clinical Trial Progress for LOSARTAN POTASSIUM AND HYDROCHLOROTHIAZIDE

Clinical Trial Phase

Clinical Trial Phase for LOSARTAN POTASSIUM AND HYDROCHLOROTHIAZIDE
Clinical Trial Phase	Trials
Phase 4	3
Phase 3	5
Phase 1	5

Clinical Trial Status

Clinical Trial Status for LOSARTAN POTASSIUM AND HYDROCHLOROTHIAZIDE
Clinical Trial Phase	Trials
Completed	13
Recruiting	1
Terminated	1

Clinical Trial Sponsors for LOSARTAN POTASSIUM AND HYDROCHLOROTHIAZIDE

Sponsor Name

Sponsor Name for LOSARTAN POTASSIUM AND HYDROCHLOROTHIAZIDE
Sponsor	Trials
Merck Sharp & Dohme Corp.	5
Torrent Pharmaceuticals Limited	2
Roxane Laboratories	2

Sponsor Type

Sponsor Type for LOSARTAN POTASSIUM AND HYDROCHLOROTHIAZIDE
Sponsor	Trials
Industry	11
Other	6

Losartan Potassium and Hydrochlorothiazide Clinical Trials Update, Market Analysis, and Generic/Biosimilar Launch Projections

Last updated: July 27, 2026

Executive summary

• Product scope: Fixed-dose combination (FDC) of losartan potassium (ARB) plus hydrochlorothiazide (HCTZ; thiazide diuretic) for hypertension.
• Clinical trials status: Public trial activity is dominated by bioequivalence/bridging and post-approval studies supporting generics and alternate formulations, with fewer high-impact new efficacy endpoints because the combination is already established and off-patent in most markets.
• Market outlook: Revenue exposure tracks global hypertension demand, ARRB plus diuretic guideline use, and pricing pressure after generic entry; growth is mainly in EMEA and APAC through volume expansion rather than new clinical differentiation.
• Exclusivity/IP risk: For most geographies, brand exclusivity has lapsed, making generic FDC launches the primary commercial event. Litigation risk is typically driven by ANDA paragraph IV and formulation/manufacturing changes, not a new mechanism of action.

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What clinical trials exist for losartan potassium and hydrochlorothiazide, and what do they show?

Direct answer: Most currently visible “clinical trials” for losartan/HCTZ are bioequivalence (BE), pharmacokinetic (PK), and formulation or manufacturing studies. These are used for generic approval and label maintenance rather than for new cardiovascular outcomes.

Trial types you should expect in the public record

1. Bioequivalence and PK bridging

   • Compare generic vs. reference FDC tablet under fasting/fed or standard conditions.
   • Endpoints: Cmax, Tmax, AUC, and exposure variability.

2. Safety/tolerability and adherence studies

   • Often short duration.
   • Focus: BP control, electrolyte monitoring, adverse events typical for ARB+HCTZ (eg, dizziness, hypotension, renal function changes).

3. Renal and metabolic subgroup studies

   • CKD, diabetes, or elderly cohorts appear in smaller trials.
   • Outcomes: tolerability and laboratory changes more than long-term endpoints.

How to interpret “activity” for a mature hypertension FDC

• If trials do not report CV morbidity/mortality endpoints or novel populations, they do not materially shift the standard of care.
• For commercialization planning, BE/PK activity is a reliable signal of impending generic entry and formulation lifecycle management.

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When will losartan potassium and hydrochlorothiazide approvals and launches shift due to clinical trial milestones?

Direct answer: For an established FDC, the commercial inflection points align with ANDA/BE completions and regulatory approvals, not phase 3 efficacy readouts.

Milestone-to-launch mapping (practical planning view)

• BE study completion → internal dossier finalization and ANDA readiness.
• ANDA submission → FDA review window for generic approval.
• Approval → product launch timing driven by supply chain and labeling finalization.
• Court/settlement (if any patent litigation exists for a specific reference brand in a specific jurisdiction) → potential delay, then launch after stay lifting.

What typically moves the market without new phase 3 data

• Switching and formulary updates: payers and formularies tend to add low-cost generics after approval rather than waiting for new trials.
• Product switching: patients already on ARB+diuretic regimens switch to FDC generics for dosing convenience.

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What is the current market size and demand profile for losartan potassium and hydrochlorothiazide?

Direct answer: Demand tracks hypertension prevalence and the share of patients treated with combination therapy rather than monotherapy. The ARB+thiazide class is widely used due to tolerability and dosing simplicity.

Market drivers

• Guideline adoption: combination therapy is frequently recommended when monotherapy fails or when baseline BP is significantly elevated.
• Physician preference for FDCs: improves adherence versus separate tablets.
• Diuretic pricing: HCTZ-based combinations remain cost-effective, supporting payers’ preference for generics.

Market headwinds

• Pricing erosion after generic entry: standard dynamic for older FDCs.
• Substitution risk: prescribers can switch among ARB+HCTZ and ARB+chlorthalidone or to different ARB combinations.

Demand segment shape (how it typically breaks out)

• Higher utilization in:
  • primary care and cardiology clinics
  • elderly patients due to common hypertension comorbidity burden
• Lower differentiation: most products are therapeutically interchangeable at label level.

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How many generic versions of losartan potassium and hydrochlorothiazide tablets are on the market?

Direct answer: The category is widely genericized. The dominant landscape consists of multiple ANDA products across strengths (commonly 50/12.5 mg and 100/12.5 mg) with multiple manufacturers.

Why generic multiplicity matters for forecasting

• More entrants accelerate:
  • price compression
  • contracting intensity
  • margin pressure on branded or higher-cost generics

Practical forecasting impact

• If your model is based on “market share capture,” include:
  • rapid post-approval erosion
  • higher switching rates due to FDC convenience
  • payer-level contracting that can consolidate supply among 2 to 4 lowest-cost options

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What patent estate and Orange Book status govern losartan potassium and hydrochlorothiazide exclusivity?

Direct answer: For this long-established antihypertensive FDC, exclusivity and patent coverage in the US typically relates to:

• reference brand patents (already expired in many scenarios),
• plus residual method/formulation patents for specific strengths or product variants, depending on how the reference product was protected at launch.

Planning implication for commercial strategy

• For US launch timing: the controlling question is whether any unexpired patents listed in FDA’s Orange Book still create regulatory exclusivity barriers for specific ANDA referencing.
• In most category cases: the principal commercial risk becomes litigation timing and settlement-induced launch dates, not ongoing clinical efficacy differentiation.

(No Orange Book patent listing dataset is provided in the prompt, so this section cannot enumerate specific patent numbers, listed expiration dates, or litigation stays.)

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How strong is the patent protection for fixed-dose losartan/HCTZ tablets versus generic entry risk?

Direct answer: Patent strength for this combination is usually moderate to low in practice for new entrants because the active ingredients are mature and most value shifts to manufacturing, formulation, and procedural litigation rather than novel patentable therapeutics.

What “strong protection” would look like in this category

• unexpired, narrow patents tied to:
  • specific dosage strengths or release characteristics
  • specific salt/process/manufacturing method claims
  • specific medical use claims (less common for standard hypertension indications)

What “generic entry risk” tends to be driven by

• whether patents are still listed for the specific strength being targeted
• whether a paragraph IV challenge is pending or a settlement stay delays approval
• whether the ANDA can be designed around the alleged infringement theory

(Specific strength cannot be graded without the underlying Orange Book and litigation record.)

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What paragraph IV or patent litigation affects losartan potassium and hydrochlorothiazide launches?

Direct answer: Patent litigation in this category, when present, typically involves ANDA paragraph IV challenges and disputes over:

• listed patents (method, formulation, or process),
• infringement of narrow claims tied to the reference product.

How to translate litigation into launch projections

• If there is an automatic stay triggered by a first-filer paragraph IV: launches are delayed until the stay ends unless settled.
• If settlements occur: generic entry shifts to the settlement effective date or an agreed carve-out arrangement.

(Specific case names, docket dates, and settlement details cannot be provided without a litigation dataset.)

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Which companies are likely to launch generic losartan/HCTZ products first in major markets?

Direct answer: Generic market leaders tend to include:

• large ANDA developers with high manufacturing throughput,
• firms that already operate in the ARB+diuretic space and can execute BE quickly.

How to project “first-to-launch”

Use three filters in the absence of brand-specific exclusivity data:

1. ANDA readiness (BE completed, dossier finalized)
2. formulation complexity (simple immediate-release tablets score higher)
3. supply-chain capability (immediate bulk production and distribution)

(Company ranking requires Orange Book ANDA product-level visibility not included in the prompt.)

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How does losartan potassium/hydrochlorothiazide compare with alternative hypertension combinations for market share?

Direct answer: The category competes primarily with:

• other ARB+diuretic FDCs (same class)
• ACE inhibitor+diuretic FDCs
• ARB+calcium channel blocker FDCs (often preferred when thiazide side effects or electrolyte concerns arise)

Competitive substitution dynamics

• If a payer restricts thiazide-based FDCs due to formulary preferences, ARB+CCB combinations gain.
• If contracts favor low acquisition cost, ARB+HCTZ generics gain regardless of minor clinical preference.

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What formulation patents and manufacturing barriers apply to losartan/HCTZ fixed-dose tablets?

Direct answer: Manufacturing barriers are usually procedural or claim-specific rather than platform-level. For generics, the key is BE and process reproducibility, not “hard” formulation chemistry.

Where barriers can still appear

• excipient or manufacturing process claims (when still protected)
• specific tablet properties tied to dissolution/exposure equivalence (rarely strong in older combinations)
• packaging/labeling tied to safety monitoring language (not a typical patent blocker)

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Market projection: base-case, upside, and downside scenarios for losartan/HCTZ

Direct answer: Base-case assumes ongoing generic price compression with stable volume; upside comes from volume growth and contracting favorability; downside comes from substitution to other FDCs and further payer cost pressure.

Scenario model structure (commercially actionable)

• Volume: grows with hypertension treatment rates and combination adoption.
• Price: declines after each wave of generic entry.
• Mix: higher strengths and preferred package formats can stabilize price per tablet.
• Switching: movement to ARB+CCB can cap growth in some payer segments.

Projection logic (no proprietary dataset required)

• Short term (0-2 years): stable demand, accelerating price erosion, increased market fragmentation among generics.
• Mid term (2-5 years): consolidation among lowest-cost suppliers; incremental volume gains.
• Long term (5+ years): market growth slows; category becomes predominantly “cost-plus” procurement.

(Quantitative revenue forecasts require current market size data and product-level pricing shares not included in the prompt.)

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Key takeaways

• Clinical trial activity for losartan potassium/HCTZ is mostly BE/bridging, which supports continued generic expansion rather than new efficacy paradigms.
• The market is driven by hypertension prevalence, combination therapy adoption, and payer preference for low-cost FDCs.
• Commercial upside is constrained by pricing pressure and therapeutic substitution to other FDC combinations.
• Patent and litigation dynamics, where they exist, are generally procedural barriers around ANDA launches, not durable therapeutic differentiation.

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FAQs

1. Do losartan potassium and hydrochlorothiazide require bioequivalence studies for generic approval?
2. What strength combinations (50/12.5 mg vs 100/12.5 mg) are most targeted by generic manufacturers?
3. How do payer formularies affect switching from monotherapy to losartan/HCTZ fixed-dose combination?
4. What are the most common adverse events monitored in clinical studies of losartan/HCTZ?
5. How does FDA labeling for ARB+thiazide combinations influence substitution at the pharmacy level?

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References

(No sources were provided in the prompt, and no external datasets were supplied. Therefore, no citations can be generated.)