Clinic blood pressure responses to two amlodipine salt formulations, adipate and besylate, in adult Korean patients with mild to moderate hypertension: A multicenter, randomized, double-blind, parallel-group, 8-week comparison

Serum uric acid change in relation to antihypertensive therapy with the dihydropyridine calcium channel blockers

PURPOSE

We investigated serum uric acid changes in relation to the achieved clinic and ambulatory blood pressure after 8 weeks of antihypertensive therapy with two dihydropyridine calcium channel blockers.

MATERIALS AND METHODS

The study participants were patients with clinic and ambulatory hypertension, enrolled in a randomised controlled trial that compared amlodipine (5-10 mg, n = 215) and nifedipine gastrointestinal therapeutic system (GITS, 30-60 mg, n = 203). Hyperuricaemia was defined as a serum uric acid concentration of ≥420 µmol/L in men and ≥360 µmol/L in women. Analysis of covariance and multiple regression analyses were performed to study the associations between serum uric acid changes and the achieved clinic and ambulatory blood pressure during follow-up.

RESULTS

At baseline, 67 (16.0%) of the 418 patients had hyperuricaemia. Antihypertensive treatment reduced clinic and 24-h daytime and night-time systolic/diastolic blood pressure by a mean (±standard error [SE]) change of -17.4 ± 0.6/-8.6 ± 0.4 mm Hg and -13.7 ± 0.5/-8.3 ± 0.3 mm Hg, -13.8 ± 0.6/-8.4 ± 0.4 mm Hg, and -12.7 ± 0.7/-8.0 ± 0.4 mm Hg, respectively. Antihypertensive treatment reduced serum uric acid by a mean (±SE) change of -9.3 ± 2.8 μmol/L. The serum uric acid changes differed according to the achieved clinic and ambulatory blood pressure, and were statistically significant (mean ± SE -20.6 ± 6.6 to -10.7 ± 2.9 μmol/L, p ≤ 0.04) at the systolic/diastolic ranges of 130-139/≥90 mm Hg in clinic pressure, and <130/75-84 mm Hg, <145/80-84 mm Hg and <120/65-69 mm Hg in 24-h, daytime and night-time ambulatory pressure.

CONCLUSION

Our study showed that antihypertensive therapy with a dihydropyridine calcium channel blocker was associated with reduced serum uric acid, especially when 24-h ambulatory systolic blood pressure was controlled.

Pharmacogenomics of amlodipine and hydrochlorothiazide therapy and the quest for improved control of hypertension: a mini review

Blood pressure (BP) is a complex trait that is regulated by multiple physiological pathways and include but is not limited to extracellular fluid volume homeostasis, cardiac contractility, and vascular tone through renal, neural, or endocrine systems. Uncontrolled hypertension (HTN) has been associated with an increased mortality risk. Therefore, understanding the genetics that underpins and influence BP regulation will have a major impact on public health. Moreover, uncontrolled HTN has been linked to inter-individual variation in the drugs’ response and this has been associated with an individual’s genetics architecture. However, the identification of candidate genes that underpin the genetic basis of HTN remains a major challenge. To date, few variants associated with inter-individual BP regulation have been identified and replicated. Research in this field has accelerated over the past 5 years as a direct result of on-going genome-wide association studies (GWAS) and the progress in the identification of rare gene variants and mutations, epigenetic markers, and the regulatory pathways involved in the pathophysiology of BP. In this review we describe and enhance our current understanding of how genetic variants account for the observed variability in BP response in patients on first-line antihypertensive drugs, amlodipine and hydrochlorothiazide.

Formulations of Amlodipine: A Review

Amlodipine (AD) is a calcium channel blocker that is mainly used in the treatment of hypertension and angina. However, latest findings have revealed that its efficacy is not only limited to the treatment of cardiovascular diseases as it has shown to possess antioxidant activity and plays an important role in apoptosis. Therefore, it is also employed in the treatment of cerebrovascular stroke, neurodegenerative diseases, leukemia, breast cancer, and so forth either alone or in combination with other drugs. AD is a photosensitive drug and requires protection from light. A number of workers have tried to formulate various conventional and nonconventional dosage forms of AD. This review highlights all the formulations that have been developed to achieve maximum stability with the desired therapeutic action for the delivery of AD such as fast dissolving tablets, floating tablets, layered tablets, single-pill combinations, capsules, oral and transdermal films, suspensions, emulsions, mucoadhesive microspheres, gels, transdermal patches, and liposomal formulations.

Bioequivalence evaluation of two amlodipine salts, besylate and orotate, each in a fixed-dose combination with olmesartan in healthy subjects

A fixed-dose combination of amlodipine and olmesartan is used to treat high blood pressure in patients whose hypertension is not sufficiently controlled with either drug alone. The objective of this study was to evaluate the bioequivalence of two fixed-dose combinations, ie, amlodipine orotate/olmesartan medoxomil 10/40 mg and amlodipine besylate/olmesartan medoxomil 10/40 mg, in healthy subjects. A randomized, open-label, single-dose, two-sequence, two-period, crossover study was conducted in 30 healthy adult volunteers. Blood samples were collected for up to 72 hours post-dose in each period. Safety data included the results of physical examinations, clinical laboratory tests, vital signs, an electrocardiogram, and adverse events. For both amlodipine and olmesartan, the 90% confidence intervals for the geometric mean ratios of AUC_last and time to peak plasma concentration fell within the bioequivalence acceptance criteria. The two fixed-dose combinations showed similar safety profiles. Amlodipine orotate/olmesartan medoxomil 10/40 mg was bioequivalent to amlodipine besylate/olmesartan medoxomil 10/40 mg.

The therapeutic advantage of combination antihypertensive drug therapy using amlodipine and irbesartan in hypertensive patients: Analysis of the post-marketing survey data from PARTNER (Practical combination therapy of Amlodin and angiotensin II Receptor blocker; safety and efficacy in patients with hypertension) study

Two-thirds of hypertensive patients need a combination antihypertensive therapy to achieve the target blood pressure (BP). The PARTNER (Practical combination therapy of Amlodin and angiotensin II Receptor blocker; Safety and efficacy in paTieNts with hypERtension) study is a prospective specific clinical use survey examining the efficacy and safety of 12-week treatment with amlodipine (AML) and Angiotensin II Receptor Blocker (ARB) in 5900 hypertensive patients. The current analysis was performed as to the BP control, adverse reactions, and the effects on laboratory data in patients treated with the combination of AML and irbesartan (IRB), namely the patients added AML to already taking IRB (AML add-on group, n = 1202) and the patients added IRB to AML (IRB add-on group, n = 1050). Both study groups showed distinct decreases in office BP at 4 week (p < 0.001) and the antihypertensive effects were sustained to 12 week (p < 0.001). The percentage of patients achieving BP < 140/90 mmHg was ∼70% in either group. Proteinuria and estimated glomerular filtration rate (eGFR) were significantly improved in hypertensive patients with baseline eGFR <60 ml/min/1.73 m(2). Serum uric acid was reduced either by adding AML or IRB, and the reductions were prominent in patients with serum uric acid >7 mg/dl. The incidence of adverse reactions was as few as 1.11% and there were no severe adverse reactions which hampered the continuation of combination therapy. In conclusion, combination antihypertensive therapy with AML and IRB effectively lowers BP without particular safety problems, reduces serum uric acid especially in patients with hyperuricemia and exhibits renoprotective effects in patients with chronic kidney disease.

Blood pressure responder rates versus goal rates: which metric matters?

Reducing blood pressure (BP) to guideline-recommended goals associated with reductions in cardiovascular risk is central to effective hypertension management. In addition to measuring BP reduction, clinical trials of antihypertensive agents should assess the percentage of patients responding to treatment. The Food and Drug Administration's defined rate of response required for drug approval is a reduction in diastolic BP (DBP) to <90 mmHg and/or a DBP reduction of > or = 10 mmHg. Consequently, some patients may be counted as responders even if they have not reached DBP <90 mmHg. An antihypertensive agent's effectiveness may be better assessed by the proportion of patients who achieve recommended BP goals. This article analyzes the frequency of response rates versus goal rates as endpoints in randomized trials since January 2001. Data showed that goal rates, especially combined systolic BP (SBP)/DBP goal rates, are consistently lower than response rates in studies evaluating both endpoints. Goal rates incorporating both SBP and DBP, or having a focus on SBP for individuals >50 years of age, provide the most clinically relevant information and are a more clinically relevant metric of an agent's ability to reduce BP than DBP alone.

Losartan/Hydrochlorothiazide fixed combination versus amlodipine monotherapy in korean patients with mild to moderate hypertension

Background and Objectives

The antihypertensive efficacy and tolerability of losartan (LST) in fixed combination with hydrochlorothiazide (HCTZ) has not been compared to those of amlodipine monotherapy in Asians. This is an important comparison to draw, because Asians have been suggested to respond more favorably to calcium channel blockers and less favorably to angiotensin-converting enzyme inhibitors in comparison to Westerners. We sought to compare these two regimens in Korean patients with mild to moderate hypertension.

Subjects and Methods

174 patients were randomized to receive LST 50 mg once daily, which could be titrated to LST/HCTZ 50/12.5 mg at 4 weeks, followed by 100/25 mg at 8 weeks; or to receive amlodipine besylate 2.5 mg once daily, which could be titrated to 5 mg at 4 weeks, followed by 10 mg at 8 weeks to achieve diastolic blood pressure <90 mmHg.

Results

At 12 weeks, the differences between the LST/HCTZ and amlodipine groups with regard to diastolic and systolic blood pressure were 1.2 mmHg (95% confidence interval: -1.1 to 3.4) and -0.5 mmHg (95% confidence interval: -4.3 to 3.4), respectively. The rates of achieving systolic blood pressure <140 mmHg were 66.7% in the LST/HCTZ group and 75.9% in the amlodipine group (p=0.20). The rates of drug-related adverse events were 15.6% in the LST/HCTZ group and 11.9% in the amlodipine group (p=0.49).

Conclusion

The two regimens, with a relatively higher dose of LST/HCTZ compared to that required in Westerners, produced equivalent blood pressure reduction and were comparably well tolerated in Korean patients with mild to moderate hypertension.

Efficacy and safety profiles of a new S(-)-amlodipine nicotinate formulation versus racemic amlodipine besylate in adult Korean patients with mild to moderate hypertension: an 8-week, multicenter, randomized, double-blind, double-dummy, parallel-group, phase III, noninferiority clinical trial

BACKGROUND

"Chiral switching" from an existing racemate to a pure enantiomeric compound is a popular theme in drug development, especially when the enantiomer is found to have better efficacy and safety profiles. Amlodipine is a racemic mixture, composed of the S(-)-enantiomer, which is the pharmacologically active isomer, and the R(+)-enantiomer, which is 1000-fold less active. S(-)-amlodipine nicotinate, a chirally switched form of amlodipine nicotinate, has been developed and found to be bioequivalent to amlodipine besylate in Phase I clinical trials in Korea.

OBJECTIVE

The aim of this study was to compare the efficacy and safety profiles of S(-)-amlodipine nicotinate with those of amlodipine besylate in adult Korean patients with mild to moderate hypertension (diastolic blood pressure [DBP] >or=90 mm Hg and <or=109 mm Hg).

METHODS

This was an 8-week, multicenter, randomized, double-blind, double-dummy, parallel-group, Phase III, noninferiority clinical trial. After an initial 2-week placebo run-in period, patients aged 18 to 75 years with sitting DBP (SiDBP) >or=90 and <or=109 mm Hg at day 0 (baseline) were randomly allocated to receive S(-)-amlodipine nicotinate 2.5 mg QD or amlodipine besylate 5 mg QD for 8 weeks. The dose of study medication was doubled after 4 weeks in patients who had not responded to treatment (SiDBP >or=90 mm Hg). The primary end point was noninferiority of the difference in mean SiDBP from baseline to week 8 for S(-)-amlodipine nicotinate compared with amlodipine besylate. Secondary end points were as follows: (1) noninferiority of the difference in mean sitting systolic blood pressure (SiSBP) from baseline to week 8 between the study groups; and (2) SiDBP response rate (defined as the proportion of patients whose SiDBP was <90 mm Hg or whose SiDBP reduction was >or=10 mm Hg from baseline) after the 8-week treatment. Also, the incidence and severity of adverse events (AEs) and adverse drug reactions (ADRs) were reported. Severe AEs/ADRs were defined as those associated with any of the following: death; an event associated with a high risk of mortality; an event requiring hospitalization; or development of a permanent disability or congenital malformation.

RESULTS

One hundred fifty-seven patients were assessed for inclusion in the study. Of these, 124 patients were randomly allocated to receive S(-)-amlodipine nicotinate (42 men, 21 women; mean [SD] age, 52.4 [10.3] years [range, 23-70 years]; weight, 67.7 [10.8] kg [range, 44-92 kg]) or amlodipine besylate (45 men, 16 women; mean [SD] age, 54.5 [10.0] years [range, 30-73]; weight, 68.9 [9.8] kg [range, 49-95 kg]). One hundred sixteen patients completed the study, but 11 patients (8.9%) were dropped from the per-protocol analysis due to violations; therefore, 105 patients were included in the modified intent-to-treat population analysis (S[-]-amlodipine nicotinate, 55 patients; amlodipine besylate, 50 patients). There were no significant between-group differences in the baseline characteristics. Baseline mean (SD) SiSBP and SiDBP were 142.6 (11.3) and 94.9 (4.8) mm Hg in the S(-)-amlodipine nicotinate group, and 141.8 (8.3) and 96.1 (4.9) mm Hg in the amlodipine besylate group. Mean (SD) changes in SiSBP were 17.6 (11.2) mm Hg in the S(-)-amlodipine nicotinate group and 18.6 (12.3) mm Hg in the amlodipine besylate group. The SiDBP response rates were 92.7% in the S(-)-amlodipine nicotinate group and 88.0% in the amlodipine besylate group. There were no significant between-group differences in the prevalence of AEs and ADRs. In the S(-)-amlodipine nicotinate group, 15 patients (23.8%) reported a total of 28 AEs, and 19 patients (31.1%) reported a total of 27 AEs in the amlodipine besylate group. Six patients (9.5%) in the S(-)-amlodipine nicotinate group and 7 patients (11.4%) in the amlodipine besylate group experienced a total of 19 ADRs (11 and 8, respectively). The most common ADRs were liver enzyme elevation (3/63 [4.8%]) in the S(-)-amlodipine nicotinate group and facial flushing (3/61 [4.9%]) in the amlodipine besylate group. No cases of severe AEs or ADRs were reported in either group.

CONCLUSIONS

The reduction of SiDBP after 8 weeks of treatment with S(-)-amlodipine nicotinate was noninferior compared with that of racemic amlodipine besylate in these adult Korean patients with mild to moderate hypertension. The SiDBP response rate and the reduction of SiSBP after 8 weeks of treatment with S(-)-amlodipine nicotinate were not significantly different from those with racemic amlodipine besylate. Both treatments were generally well tolerated.

Comparison of efficacy and tolerability of amlodipine orotate versus amlodipine besylate in adult patients with mild to moderate hypertension: A multicenter, randomized, double-blind, placebo-controlled, parallel-group, 8-week follow-up, noninferiority trial

OBJECTIVE

The purpose of this study was to compare the efficacy and tolerability of amlodipine orotate with those of amlodipine besylate in Korean patients with mild to moderate hypertension.

METHODS

This multicenter, randomized, double-blind, placebo-controlled, parallel-group study was designed as a noninferiority study. To be included in the study, previously untreated patients had to have a sitting diastolic blood pressure (SiDBP) of 90 to 109 mm Hg. Previously treated patients had to discontinue their current annhypertensive medications and have a baseline SiDBP between 90 and 109 mm Hg after a 2-week washout period. Patients who met the inclusion criteria were randomly assigned to receive 5 mg amlodipine orotate or 5 mg amlodipine besylate for 8 weeks. The medication dose was doubled (10 mg QD for either amlodipine orotate or amlodipine besylate) 4 weeks after enrollment if SiDBP was >or=90 mm Hg. The primary efficacy analysis was noninferiority of the difference in mean trough SiDBP changes from baseline for amlodipin eorotate as compared with amlodipine besylate after 8 weeks of treatment. For the secondary efficacy analysis, 2 other measures were analyzed after 8 weeks of treatment. The SiDBP response rate was defined as an SiDBP measurement<90 mm Hg at the last clinical follow-up visit or an absolute reduction of >or=10 mm Hg in SiDBP from baseline until the last clinical follow-up visit. In addition, noninferiority of the difference in mean trough sitting systolic blood pressure (SiSBP) changes from baseline was analyzed for amlodipine orotate as compared with amlodipine besylate. The drug compliance rate was estimated by pillcount.

RESULTS

Eligible patients (n=109; 43 women and 66 men) were randomly assigned to receive amlodipine orotate (n=53) or amlodipine besylate (n=56). No significant differences were found in sex, age, weight, or current smoking between the groups (all, P=NS). The proportion of patients with previous antihypertensive medications was not different between the groups (47.2% [25/53] in the amlodipine orotate group and 50.0% [28/56] in the amlodipine besylate group; P=NS). No significant differences were found in baseline SiDBP (mean [SD], 100 [6] mm Hg [range, 90-109 mm Hg] in the amlodipine orotate group and 100 [6] mm Hg [range, 90-108 mm Hg] in the amlodipine besylate group; P=NS) or in baseline SiSBP (mean [SD], 149 [14] mm Hg [range, 125-179 mm Hg] in the amlodipine orotate group and 146 [10] mm Hg [range, 123-167 mm Hg] in the amlodipine besylate group; p=NS). The mean (SD) changes in SiDBP were -15.6 (6.3) mm Hg for the amlodipine orotate group and -14.5 (5.5) mm Hg for the amlodipine besylate groups was 1.1 (5.9) mm Hg (95% CI, -0.87 to infinity), and because the lower boundary of the 95% CI was greater than -5 mm Hg, amlodipine orotate was considered noninferior to amlodipine besylate. The response rate was 48 of 51 (94.1%) in the amlodipine orotate group compared with 50 (92.6%) of 54 in the amlodipine besylate group after 8 weeks of treatment (P=NS). The mean (SD) compliance rates were 97.6% (3.6%) in the amlodipine orotate group and 96.5% (4.3%) in the amlodipine besylate group (P=NS). The incidence of drug-related adverse events (AEs) was similar between the groups (1/53 [1.9%]) in the amlodipine orotate group vs 4/55 [7.3%] in the amlodipine besylate group; P=NS). The most common drug-related AE overall was peripheral edema (2/55 [3.6%]), and the most common of all the AEs was upper respiratory tract infection (4/55 [7.3%]) in the amlodipine besylate group. The most common drug-related AE was headache (1/53 [1.9%]) in the amlodipine orotate group and peripheral edema (2/55 [3.6%]) in the amlodipine besylate group. No severe AEs were found in either group.

CONCLUSION

The reduction in SiDBP after 8 weeks of amlodipine orotate treatment was noninferior to that of amlodipine besylate in these Korean patients with mild to moderate hypertension. The SiDBP response rate and the reduction in SISBP after 8 weeks of amlodipine orotate treatment were not significantly different from those of amlodipine besylate treatment. Both agents were wel tolerated.