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Comparator: losartan +/- HCTZ
Losartan is an angiotensin II receptor antagonist that blocks vasoconstriction and aldosterone secretion to lower blood pressure; HCTZ is a thiazide diuretic that reduces fluid volume.
Losartan is an angiotensin II receptor antagonist that blocks vasoconstriction and aldosterone secretion to lower blood pressure; HCTZ is a thiazide diuretic that reduces fluid volume. Used for Hypertension (as combination therapy or monotherapy with losartan).
At a glance
| Generic name | Comparator: losartan +/- HCTZ |
|---|---|
| Sponsor | Organon and Co |
| Drug class | Angiotensin II receptor blocker (ARB) + thiazide diuretic combination |
| Target | AT1 angiotensin II receptor; sodium-chloride cotransporter (HCTZ) |
| Modality | Small molecule |
| Therapeutic area | Cardiovascular |
| Phase | Phase 3 |
Mechanism of action
Losartan selectively blocks AT1 angiotensin II receptors, preventing the hormone's vasoconstrictive and sodium-retaining effects, thereby reducing blood pressure and protecting target organs. Hydrochlorothiazide (HCTZ) inhibits sodium reabsorption in the distal convoluted tubule, increasing urinary sodium and water excretion to decrease blood volume and pressure. The combination provides complementary mechanisms for enhanced antihypertensive efficacy.
Approved indications
- Hypertension (as combination therapy or monotherapy with losartan)
Common side effects
- Dizziness
- Fatigue
- Hyperuricemia (HCTZ-related)
- Hypokalemia (HCTZ-related)
- Cough (less common with ARB than ACE inhibitor)
- Hyperglycemia (HCTZ-related)
Key clinical trials
- HYZAAR vs. Ramipril for Diabetes (0954A-245)(COMPLETED) (PHASE3)
- Losartan and HCTZ and Amlodipine vs Atenolol and Amlodipine (0954A-309)(COMPLETED) (PHASE4)
- A Study of Losartan Compared to Losartan/HCTZ in Pediatric Patients With Hypertension (0954A-327) (PHASE3)
- LAAS (Losartan Anti-Atherosclerosis Study)(0954-330)(COMPLETED) (PHASE4)
- MK-0954A in Japanese Patients With Essential Hypertension Not Adequately Controlled With Losartan (MK-0954A-352) (PHASE3)
- A Long-term Study of the Safety of MK-0954A in Patients With Essential Hypertension (MK-0954A-351) (PHASE3)
- BP-EASE -Effectiveness of Losartan 50 mg/Hydrochlorothiazide (HCTZ) 12.5 mg Versus Valsartan 80 mg/HCTZ 12.5 mg Titrated as Needed in Patients With Essential Hypertension Not Controlled on Monotherapy (0954A-333) (PHASE3)
- Antihypertensive Efficacy and Safety of Approved Drugs in Japanese Patients With Essential Hypertension (Banyu Study)(0954A-302) (PHASE3)
Primary sources
Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.
| Source | Used for |
|---|---|
| ClinicalTrials.gov | Trial enrolment, design, endpoints, results |
Competitive intelligence
For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:
- Comparator: losartan +/- HCTZ CI brief — competitive landscape report
- Comparator: losartan +/- HCTZ updates RSS · CI watch RSS
- Organon and Co portfolio CI