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Randomised controlled trial to assess effectiveness of ultra-low-dose quadruple combination therapy in participant with hypertension

An investigator initiated and conducted, multicentre, double blind randomised controlled trial to assess the effectiveness and tolerability of ultra-low-dose quadruple combination therapy (‘LDQT’) in participants with hypertension
To investigate in a double blind randomised controlled trial whether initiating treatment with ultra-low-dose quadruple-combination therapy (‘LDQT’) will lower blood pressure more effectively, and with fewer side effects, compared to initiating standard dose monotherapy as per current guidelines in patients with hypertension.

Primary hypothesis:

A combination pill comprising four types of blood pressure lowering medications each at ¼ standard doses will lower blood pressure more effectively than initiating patients with standard dose monotherapy as per current guideline-recommended therapy.

Study Design:

A 12-week double blind randomised controlled trial comparing ultra-low dose quadruple combination therapy (LDQT) with standard dose irbesartan in participants with grade 1 and 2 essential hypertension with 12 months extension substudy to assess longer term effects and tolerability.

Ethics approval number:  HREC/15/WMEAD/422


You may be eligible to participate in this study if you:

Inclusion Criteria:
• Adults (≥18 years)
• Previous documentation of hypertension or high blood pressure (SBP 140-179mmHg and/or DBP 90-109 mmHg) from GP, pharmacist or health care professional
• And either:
- A measure of Clinic SBP 140-179mmHg and/or DBP 90-109 mmHg documented by study staff in the last 12 weeks with a study automatic BP device OR
- A recorded measure of daytime average SBP ≥ 135 mmHg and/or DBP ≥ 85 mmHg on a 24 hour ambulatory BP monitoring device in the last 12 weeks
• And one of the following:
- Treatment naïve (i.e. never treated)
- Currently not on treatment (not taken in last 4 weeks)
- Currently taking one BP lowering drug (i.e. ACE-I, ARB, CCB, BB, aldosterone antagonist, alpha-blocker)
 Exclusion criteria:
• Contraindication to irbesartan, amlodipine, indapamide or bisoprolol
• Evidence of secondary cause of hypertension e.g. renal artery stenosis; Significant renal impairment (eGFR <50), raised serum potassium (above lab normal limit)
• Women who are pregnant, breast feeding and/ or of childbearing potential and not using effective contraception throughout the study (pharmacological or barrier methods)
• Concomitant illness, physical impairment or mental condition which in the opinion of the study team/ primary care physician could interfere with the conduct of the study including outcome assessments
• Participation in a concurrent clinical trial of an investigational medical product. Patients in trials of approved medical products, or in observational, natural history and/or epidemiological studies not involving an intervention are eligible.
• Participants responsible primary care or other responsible physician believes it is not appropriate for participant to switch current monotherapy or initiate study drug.
• Inability or unwillingness to provide written informed consent
• Unable to complete study procedures including 24 hour ABP
• Definite indication for combination therapy

How to participate

Register your interest for this study,  please email us here,  in the first instance.