Rationale for triple fixed-dose combination therapy with an angiotensin II receptor blocker, a calcium channel blocker, and a thiazide diuretic

Single-Pill, Triple Antihypertensive Therapy in Rural Sub-Saharan Africa: Preliminary Experience

INTRODUCTION

Worldwide, arterial hypertension is the foremost preventable and modifiable cardiovascular risk factor. In addition to lifestyle changes, recent international guidelines recommend single-pill, low-dose combinations as initial treatment strategy. We investigated whether this approach is feasible in a rural sub-Saharan Africa setting.

METHODS

Diagnosis of hypertension was established over three sets of blood pressure measurements, performed according to the European Society of Hypertension recommendations by trained personnel, using a validated, automated, oscillometric device OMRON M7 IT-HEM-7322-E. In 98 individuals with arterial hypertension, a once-daily, single-pill combination of olmesartan, amlodipine, and hydrochlorothiazide was prescribed at an appropriate dose. Patients were instructed on its administration and potential side effects and encouraged towards lifestyle modifications. The treatment regimen was adjusted, if needed, at each outpatient clinic scheduled after 4, 8, 12, and 16 weeks.

RESULTS

Seventy-nine patients (aged 61 [53-70] years; median and interquartile range) strictly adhered to the treatment schedule, while 19 individuals (70 [65-80] years) dropped out. Blood pressure was < 140/90 mmHg after 4 weeks in 44 (56%), after 8 weeks in 62 (78%), after 12 weeks in 69 (87%), and after 16 weeks in 74 (94%) participants. Excellent tolerance was reported.

CONCLUSIONS

These results provide real-life evidence that hypertension management with a once-daily, single-pill combination of olmesartan, amlodipine, and hydrochlorothiazide as initial treatment is feasible and effective also in a rural sub-Saharan setting. Single-pill combinations should be made available also in rural and remote areas in low- and middle-income countries as a reliable first-line treatment strategy.

Response surface analyses of antihypertensive effects of angiotensin receptor blockers and amlodipine or hydrochlorothiazide combination therapy in patients with essential hypertension

While previous studies have examined the dose-response characteristics of certain antihypertensive drugs alone or in combination, response surface analysis for combination therapies involving angiotensin receptor blockers (ARBs) and either amlodipine (AML) or hydrochlorothiazide (HCT) has not been explored, particularly in the context of low-dose combinations. The objectives of present study were to generate useful dose-response information for the combination of ARB/AML or ARB/HCT and to predict the blood pressure lowering effects of combination therapies compared to monotherapies. We reviewed the New Drug Application data of combination drugs of ARB/AML and ARB/HCT. Data on systolic blood pressure (SBP), from studies conducted using a factorial dose-response design over a period of 8-12 weeks, were used. The placebo-subtracted SBP change was used for analysis. Response surface analyses of the collected data were conducted using a polynomial regression model. For ARB/AML combination, the quadratic polynomial regression model containing two linear terms, two quadratic terms, and one interaction term was best fitted to the naïve pooled data. Meanwhile, for ARB/HCT combination, the best-fitted model was a quadratic model that included two linear terms and two quadratic terms. The 1/2-dose combination of these medications, compared to each monotherapy, resulted in predicted SBP reductions that were 8-30% greater. The ratio of the estimated antihypertensive effects of the combination to the expected additive effects of each component ranged from 82% to 100% of the expected effect. These results can provide a rationale for developing lower-dose combinations of ARB/AML or ARB/HCT and assist in designing clinical trials.

Single-Pill Combination with Three Antihypertensive Agents to Improve Blood Pressure Control in Hypertension: Focus on Olmesartan-Based Combinations

Blood pressure control remains an unmet clinical need. Only about half of patients achieve their blood pressure (BP) targets and of these, the majority require combination and double or triple therapies. International guidelines recommend the association of drugs with complementary mechanisms of action and, in particular, the combination of renin-angiotensin system (RAS) inhibitors, calcium channel blockers (CCBs), and diuretics. Among the various angiotensin receptor blockers, olmesartan (OM) is available as a monotherapy and in dual and triple single-pill combinations (SPCs) with amlodipine (AML) and/or hydrochlorothiazide (HCTZ). Several phase III and IV studies, together with real-world studies, have demonstrated the additional benefits of combining OM either with AML or with HCTZ in terms of BP control and target BP achievements both in the general population and in special subgroups of hypertensive patients, such as the elderly, diabetic, chronic kidney disease or obese patients. Ambulatory BP monitoring studies assessing 24h BP have also demonstrated that dual, as well as triple, OM-based SPCs induce a more sustained and smoother BP reduction than placebo and monotherapy. Furthermore, triple OM-based SPC has been shown to improve therapeutic adherence in hypertensive patients compared to free combinations. The availability of OM combined with HCTZ, AML or both at different dosages makes it a valuable option to customize therapy based on the levels of BP and the clinical characteristics of hypertensive patients.

A Rapid HPLC Method for the Concurrent Determination of Several Antihypertensive Drugs from Binary and Ternary Formulations

A rapid, synchronized liquid chromatographic method was established for the estimation of hydrochlorothiazide (HCZ), amlodipine (AMD), olmesartan (OLM), telmisartan (TEL), and irbesartan (IRB) in binary and ternary coformulations using the same chromatographic conditions. Five analytes were separated on a Zorbax C18 column using isocratic elution with a mobile phase consisting of acetonitrile, methanol, and 20 mM phosphate buffer (pH 3.5) in a ratio of 45:20:35% v/v. The analytes were detected at a wavelength of 230 nm at ambient temperature. Furthermore, the proposed liquid chromatographic procedure was validated for linearity, precision, accuracy, stability, and robustness using an experimental design. Analytes were separated with good resolution within 3.5 min. Analytes showed good linearity in a concentration satisfactory to analyze the different ratios of these analytes in the formulations. Pareto charts showed that the flow rate and mobile phase composition have a significant effect on the peak area of analytes and hence need to be carefully controlled, however, the method is robust. Finally, the different formulations consisting of HCZ, AMD, OLM, TEL, and IRB in different ratios were analyzed with high accuracy using an optimized HPLC method and compared with reported methods. Furthermore, the reported HPLC procedure is simple, rapid, and accurate and therefore can used for regular quality control of binary and ternary formulations using the same stationary and mobile phase.

Effectiveness and Adherence to Treatment with Perindopril/Indapamide/Amlodipine Single-Pill Combination in a Greek Population with Hypertension

BACKGROUND

Despite the overwhelming evidence and the established benefits of antihypertensive treatment, adherence to treatment remains low.

OBJECTIVE

To assess the adherence to treatment with a perindopril/indapamide/amlodipine single-pill combination (SPC), its effectiveness on blood pressure (BP) reduction, as well as the safety and tolerability of this SPC over a 4-month treatment period.

METHODS

This multicenter, non-interventional study prospectively included 2285 hypertensive patients on perindopril/indapamide/amlodipine SPC. The data were recorded at baseline, 1 month, and 4 months.

RESULTS

Of the 2285 hypertensive patients included in the study, 50.5% were at "high/very high risk". Mean systolic (SBP)/diastolic (DBP) decreased from 162.3 ± 13.3/93.1 ± 9.3 mmHg at baseline to 129.7 ± 8.3/78.6 ± 7.1 mmHg at 4 months (p < 0.001). Patients with higher baseline BP levels showed greater BP reduction. Patients with hypertension stages 1, 2, and 3 showed mean SBP/DBP reductions of 21.5/10.4 mmHg, 34.2/14.7 mmHg, and 51.2/22.5 mmHg, respectively, at study end (p < 0.001). Only 26 patients (1.1%) prematurely discontinued treatment (0.58% due to an adverse reaction or event).

CONCLUSIONS

Perindopril/indapamide/amlodipine SPC decreased BP levels rapidly and significantly. The degree of BP reduction was associated with the severity of hypertension and/or with total cardiovascular risk at baseline. Simplifying the drug regimen by using this SPC improved adherence and showed excellent tolerability.

Comparative Effect of Calcium Channel Blockers on Glomerular Function in Hypertensive Patients with Diabetes Mellitus

BACKGROUND

We conducted a retrospective cohort study to evaluate and compare the longitudinal effect of monotherapy with L-, L/T-, L/N-, and L/N/T-type calcium channel blockers (CCBs) on estimated glomerular filtration rate (eGFR), and to investigate the association of treatment duration with eGFR in diabetic patients with hypertension.

METHODS

Using a clinical database, we identified new users of five CCBs, i.e. amlodipine (L-type, n = 693), nifedipine (L-type, n = 189), azelnidipine (L/T-type, n = 91), benidipine (L/N/T-type, n = 183), and cilnidipine (L/N-type, n = 61). We used a multivariable regression model to evaluate and compare the effects of these drugs on eGFR and serum creatinine, up to 12 months after initiation of study drug administration.

RESULTS

There was no significant association between treatment duration and both eGFR and serum creatinine level with all CCB types. In addition, there was no significant difference in mean change in eGFR among the five CCBs, with any treatment duration.

CONCLUSIONS

Our findings suggest that monotherapy with an L-, L/T-, L/N/T-, or L/N-type CCB may have little influence on renal function parameters and may be safely used in hypertensive patients with diabetes.

Comparative effect of fixed-dose combination tablets of candesartan cilexetil/amlodipine versus olmesartan medoxomil/azelnidipine on laboratory parameters in patients with hypertension: a retrospective cohort study

We conducted a retrospective cohort study to evaluate and compare the long-term effects of two single-pill fixed-dose combinations (FDCs), candesartan/amlodipine and olmesartan/azelnidipine, on laboratory parameters in patients in routine clinical practice. We identified an equal number of new users (n = 182) of a candesartan/amlodipine (8/5 mg/day) FDC tablet (CAN/AML users) and a propensity-score matched cohort (n = 182) receiving an olmesartan/azelnidipine (20/16 mg/day) FDC tablet (OLM/AZ users). Generalized estimating equations were used to estimate and compare the effects of the drugs on serum levels of creatinine, estimated glomerular filtration rate (eGFR), blood urea nitrogen (BUN), uric acid, sodium, potassium, aspartate aminotransferase, and alanine aminotransferase levels up to 12 months after the start of study drug administration. There was a significant increase of serum creatinine level and a significant decrease of eGFR from the baseline period to during the exposure period in both CAN/AML and OLM/AZ users, and a significant increase of BUN level in CAN/AML users. However, there were no significant differences in the mean changes of laboratory parameters between CAN/AML and OLM/AZ users. Our findings suggested that the effects of CAN/AML and OLM/AZ on laboratory parameters, including an unfavorable effect on renal function, were similar at least during 1 year of administration.

Simultaneous Determination and Pharmacokinetic Study of Losartan, Losartan Carboxylic Acid, Ramipril, Ramiprilat, and Hydrochlorothiazide in Rat Plasma by a Liquid Chromatography/Tandem Mass Spectrometry Method

The monitoring of the plasmatic concentrations of cardiovascular drugs is crucial for understanding their pharmacokinetics and pharmacodynamics. A simple, sensitive, specific, and high-throughput liquid chromatography/tandem mass spectrometry (LC–MS/MS) method was developed and validated for the simultaneous estimation and pharmacokinetic study of losartan (LOS), losartan carboxylic acid (LCA), ramipril (RAM), ramiprilate (RPT), and hydrochlorothiazide (HCZ) in rat plasma using irbesartan (IBS) and metolazone (MET) as internal standards (ISs). After solid phase extraction (SPE), analytes and ISs were separated on an Agilent Poroshell 120, EC-C18 (50 mm × 4.6 mm, i.d., 2.7 μm) column with a mobile phase consisting of methanol/water (85:15, v/v) containing 5 mmol/L ammonium formate and 0.1% formic acid at a flow rate of 0.4 mL/min. The precursor → product ion transitions for the analytes and ISs were monitored on a triple quadrupole mass spectrometer, operating in the multiple reaction monitoring (MRM) mode and switching the electrospray ionization (ESI) mode during chromatography from positive (to detect LOS, LCA, RAM, RPT, and IBS) to negative (to detect HCZ and MET). The method was validated as per the FDA guidelines and it exhibited sufficient specificity, accuracy, and precision. The method was found to be linear in the range of 3–3000 ng/mL for LOS and LCA, 0.1–200 ng/mL for RAM and RPT, and 1–1500 ng/mL for HCZ. The described method was successfully applied to the preclinical pharmacokinetic study of analytes after oral administration of a mixture of LOS (10 mg/kg), RAM (1 mg/kg), and HCZ (2.5 mg/kg) in rats.

Effects of aqueous leaf extract of Asystasia gangetica on the blood pressure and heart rate in male spontaneously hypertensive Wistar rats

Background

Asystasia gangentica (A. gangetica) belongs to the family Acanthaceae. It is used to treat hypertension, rheumatism, asthma, diabetes mellitus, and as an anthelmintic in South Africa, India, Cameroun, Nigeria, and Kenya respectively. It has also been reported to inhibit the angiotensin I converting enzyme (ACE) in-vitro. Therefore, the aim of this study is to investigate the in-vivo effect of aqueous leaf extract (ALE) of A. gangetica on the blood pressure (BP) and heart rate (HR) in anaesthetized male spontaneously hypertensive rats (SHR); and to elucidate possible mechanism(s) by which it acts.

Methods

The ALE of A. gangetica (10–400 mg/kg), angiotensin I human acetate salt hydrate (ANG I, 3.1–100 μg/kg) and angiotensin II human (ANG II, 3.1–50 μg/kg) were administered intravenously. The BP and HR were measured via a pressure transducer connecting the femoral artery to a Powerlab and a computer for recording.

Results

A. gangetica significantly (p<0.05), and dose-dependently reduced the systolic, diastolic, and mean arterial BP. The significant (p<0.05) reductions in HR were not dose-dependent. Both ANG I and ANG II increased the BP dose-dependently. Co-infusion of A. gangetica (200 mg/kg) with either ANG I or ANG II significantly (p<0.05) suppressed the hypertensive effect of both ANG I and ANG II respectively, and was associated with reductions in HR.

Conclusions

A. gangetica ALE reduced BP and HR in the SHR. The reduction in BP may be a result of actions of the ALE on the ACE, the ANG II receptors and the heart rate.