In Vitro Calcium Antagonist Activity of Lercanidipine and Its Enantiomers:

New Insights into the Nephroprotective Potential of Lercanidipine

Kidneys are responsible for many crucial biological processes in the human body, including maintaining the water-electrolyte balance, pH, and blood pressure (BP), along with the elimination of toxins. Despite this, chronic kidney disease (CKD), which affects more and more people, is a disease that develops insidiously without causing any symptoms at first. The main purpose of this article is to summarize the existing literature on lercanidipine, with a particular focus on its nephroprotective properties. Lercanidipine is a third-generation dihydropyridine (DHP) blocker of calcium channels, and as such it possesses unique qualities such as high lipophilicity and high vascular selectivity. Furthermore, it acts by reversibly inhibiting L-type and T-type calcium channels responsible for exerting positive renal effects. It has been shown to reduce tissue inflammation and tubulointerstitial fibrosis, contributing to a decrease in proteinuria. Moreover, it exhibited antioxidative effects and increased expression of molecules responsible for repairing damaged tissues. It also decreased cell proliferation, preventing thickening of the vascular lumen. This article summarizes studies simultaneously comparing the effect of lercanidipine with other antihypertensive drugs. There is still a lack of studies on the medications used in patients with CKD, and an even greater lack of studies on those used in patients with concomitant hypertension. Therefore, further studies on lercanidipine and its potential in hypertensive patients with coexisting CKD are required.

Quantitative determination of lercanidipine enantiomers in commercial formulations by capillary electrophoresis

An enantioselective method based on capillary electrophoresis (CE) using cyclodextrin (CD) as chiral selector was developed and validated for determination of lercanidipine (LER) enantiomers, a drug calcium channel blocker which exerts antihypertensive effects of long duration, in a pharmaceutical formulation. Optimum separation of LER enantiomers was obtained on a 50 cm × 50 μm id capillary using a sodium acetate buffer solution 200 mmol/L pH 4.0 containing 10 mmol/L of 2,3,6-o-methyl-β-cyclodextrin (TM-β-CD) as background electrolyte. The capillary temperature and voltage were 15°C and 25 kV, respectively, hydrodynamic injection and detection at 237 nm. Linearity was obtained in the range 12.5-100 μg/mL for both enantiomers (r ≥ 0.995). The RSD (%) and relative errors (E, %) obtained in precision and accuracy studies (intraday and interday) were lower than 5%. After validation, the method was applied to quantify the enantiomers of LER in commercial tablets and the results were satisfactory in terms of accuracy and precision, both less than 5%. Therefore, this method was found to be appropriate for enantioselective quality control of LER enantiomers in pharmaceutical formulations.

Lercanidipine in the treatment of hypertension

OBJECTIVE

To review the literature regarding the efficacy, tolerability, and utility of lercanidipine in the treatment of hypertension.

DATA SOURCES

A search of the literature was performed using MEDLINE (1966-September 2006), EMBASE Drugs and Pharmacology (1980-September 2006), and Current Contents/Clinical Medicine (week 24, 2005-week 30, 2006). Package inserts from lercanidipine, nifedipine, felodipine, and amlodipine were also reviewed for comparison of adverse effects.

STUDY SELECTION AND DATA EXTRACTION

Articles were limited to clinical trials, abstracts, and review articles published in English.

DATA SYNTHESIS

Lercanidipine is a novel dihydropyridine (DHP) calcium-channel blocker indicated for the treatment of mild-to-moderate hypertension. Although it is not yet available in the US, lercanidipine has been utilized extensively in other countries. In 2 randomized controlled trials of approximately 400 patients with mild-to-moderate hypertension, lercanidipine showed efficacy similar to that of 2 other DHPs, felodipine and slow-release nifedipine, in significantly reducing systolic blood pressure and diastolic blood pressure (DBP) after 4 weeks. In a longer trial (12 mo), lercanidipine 10 mg/day led to normalized blood pressure in 49% of patients after 4 weeks. A postmarketing trial of 9050 patients corroborated the results observed in previous clinical trials, with 64% of patients achieving a DBP of less than 90 mm Hg and 32% attaining blood pressure control (<140/90 mm Hg). In elderly patients, lercanidipine was found comparable with lacidipine and nifedipine, showing similar decreases in DBP when compared with nifedipine (-18.3 vs -17.7 mm Hg, respectively). What distinguishes lercanidipine from other members of the DHP class is its lower incidence of adverse effects, particularly edema. One study showed that fewer patients withdrew secondary to adverse drug reactions in the lercanidipine (0.9%) and nifedipine (3.8%) group compared with the felodipine (4.5%) group. Lercanidipine has also shown efficacy similar to that of other antihypertensives, including atenolol, captopril, and losartan.

CONCLUSIONS

Lercanidipine may be an option in the treatment of hypertension, as current literature suggests comparable antihypertensive efficacy and better tolerability. Further randomized, double-blind clinical trials must be conducted in order to clarify its position among other antihypertensive medications.

Increased vascular selectivity and prolonged pharmacological efficacy of the L-type Ca2+ channel antagonist lercanidipine in human cardiovascular tissue

1. The present study investigates the vasoselectivity of lercanidipine (LER), a 1,4-dihydropyridine calcium channel blocker, compared with amlodipine (AML) and nifedipine (NIF) in human cardiovascular tissue. Experiments were performed either in human left ventricular failing myocardium (orthotopic heart transplants) or in isolated right atrial trabeculae and isolated vessel preparations of arteria mammaria obtained from patients undergoing aortocoronary bypass operation. 2. The obtained rank order for the L-type Ca2+ channel affinity in human tissue was LER > NIF >or= AML. Lercanidipine had the lowest negative inotropic efficacy (1 micromol/L LER: 60.3% basal < AML: 79.1% basal < NIF: 92.4 basal) and potency (IC50 NIF: 3.5 nmol/L < AML: 48 nmol/L < Ler: 127 nmol/L) in right atrial trabeculae. 3. The vasorelaxant potency of LER (IC50 0.5 nmol/L) and AML (IC50 0.8 nmol/L) was similar and significantly increased compared with that of NIF (IC50 5.9 nmol/L) in arteria mammaria preparations of the very same patients. 4. The following rank order was obtained for vasoselectivity: LER (260) < AML (60) < NIF (0.6). 5. The pharmacological effects of LER and AML were still present 2 h after drug washout. 3. Lercanidipine is characterized by a high vasoselectivity and a prolonged interaction with the L-type calcium channel in human cardiovascular tissue This may be advantageous, especially in the treatment of patients with arterial hypertension.

In vitro inhibitory effect of lercanidipine on cholesterol accumulation and matrix metalloproteinases secretion by macrophages

Plaque rupture and thromboembolism play a major role in atherosclerotic acute syndrome. Experimental studies have demonstrated the potential direct anti-atherosclerotic effects of calcium antagonists. We investigated the in vitro effect of lercanidipine (REC 15/2375), a third-generation, highly lipophilic calcium antagonist on cholesterol metabolism and matrix metalloproteinases secretion in macrophages, two functions that predispose plaques to rupture. Lercanidipine (10(-6)-10(-5) M) inhibited cholesterol esterification in macrophages and reduced cellular free and esterified cholesterol accumulation from acetylated LDL (63%, 62% of control P < 0.05, respectively). In addition, lercanidipine inhibited the release of metalloproteinases in the extracellular medium (50% and 95% inhibition at 10(-5) M for MMP-9 and MMP-2, respectively). Experiments performed with lercanidipine enantiomers or other dihydropyridine derivatives, endowed with different lipophilicity and affinity for calcium channels, indicated that the above effects could be related to the lipophilic, but not to the calcium channel blocking properties of these molecules. When cells, after exposure to the drug, were allowed to equilibrate, lercanidipine inhibitory action could be observed at initial concentrations as low as 10(-9) M, which is the actual concentration range observed in plasma in clinical settings. In conclusion, our data indicate that lercanidipine may exert potent anti-atherosclerotic effects by inhibiting macrophage functions involved in plaque stability.

Molecular mechanisms of vasoselectivity of the 1,4-dihydropyridine lercanidipine

The effects of (S)- and (R)-lercanidipine on CHO cells stably expressing the cardiac (Ca(v)1.2a) or vascular (Ca(v)1.2b) splice variant of the L-type calcium channel pore subunit were studied, using whole-cell and single-channel patch-clamp measurements. Lercanidipine block of Ca(v)1.2b current was enantioselective. (S)-lercanidipine was 4.1-fold more potent. Experiments using acidic solutions (pH 6.8) revealed a 6.4-fold enhanced inhibitory effect of (S)-lercanidipine compared with physiological conditions (pH 7.4) indicating that the charged form mediates inhibition. At depolarised holding potential (-40 mV), (S)-lercanidipine exhibited a 35-fold greater potency, compared with standard conditions (-80 mV). A comparison of the concentration-dependent inhibition of Ca(v)1.2a with Ca(v)1.2b subunit currents by (S)-lercanidipine revealed only a 1.8-fold difference in IC(50), but the slope of the dose-response curve was much steeper (n(H)=2.3) with Ca(v)1.2a, compared with Ca(v)1.2b (n(H)=0.8). This indicates overlap between agonistic and antagonistic effects, predominant with the cardiac Ca(v)1.2a subunit. This idea is supported by transient stimulatory effects, and a slight leftward shift of the IV curves. These effects were more prominent for Ca(v)1.2a than for Ca(v)1.2b. Single-channel experiments confirmed typical features of calcium channel agonists such as prolonged channel openings, a component of lengthened openings, and an enhanced open probability in the presence of (S)-lercanidipine. Again, these findings were concentration-dependent and more pronounced for Ca(v)1.2a than for Ca(v)1.2b. Our data indicate a splice-variant predominant agonism as a new mechanism contributing to the vasoselectivity of lercanidipine, along with marked voltage-dependence of action.

Quantification of leg oedema in postmenopausal hypertensive patients treated with lercanidipine or amlodipine

OBJECTIVE

Of the study was to compare the leg oedema-forming potential of two different dihydropyridine calcium channel blockers in postmenopausal women.

DESIGN

A total of 92 postmenopausal hypertensive patients [systolic blood pressure (SBP) 150-179 mmHg or diastolic blood pressure (DBP) 95-109 mmHg were randomized to receive a 4-week treatment with either 10 mg/day lercanidipine (n = 48) or 5 mg/day amlodipine (n = 44), with force-titration to 20 and 10 mg/day, respectively for an additional 4 weeks.

METHODS

Leg volume was measured by water displacement volumetry, patients were questioned for symptoms and a physical examination was performed to detect the presence of oedema.

RESULTS

A total of 77 patients completed the study, without a major protocol violation and were included in the primary analysis. Leg volume increase from baseline was significantly higher in the amlodipine than in the lercanidipine group (60.4 +/- 8.6 versus 5.3 +/- 8.1 ml; P < 0.001). The percentage of patients with evidence of oedema on physical examination (33.3 versus 9.8%, P = 0.011) and with symptoms of leg swelling (63.9 versus 22%, P < 0.001) and leg heaviness (47.2 versus 12.2%, P < 0.001) was also greater with amlodipine compared with lercanidipine. A positive correlation was found between leg volume and sign or symptoms of oedema (P < 0.001). Both drugs reduced SBP and DBP, with no significant differences between treatments. No correlation was found between leg volume changes from baseline and the antihypertensive effect of either drug.

CONCLUSIONS

In postmenopausal females with mild to moderate hypertension the oedema formation of Lercanidipine was significantly less than that of Amlodipine, despite no significant differences in the antihypertensive effect.

Lercanidipine: a novel dihydropyridine calcium-channel blocker

Calcium-channel blockers (CCBs) have been used for the treatment of hypertension for more than 20 years, and recent clinical trials support the efficacy and safety of long-acting dihydropyridine (DHP) CCBs for a wide spectrum of hypertensive patients, including diabetic hypertensive patients. DHP CCBs are effective agents overall and are particularly effective when used in combination with other agents. Lercanidipine is a novel DHP CCB effective for the treatment of mild-to-moderate hypertension. Compared with other DHP CCBs, lercanidipine has a molecular design that imparts greater solubility within the arterial cellular membrane bilayer, membrane-controlled kinetics, and a high cholesterol tolerance factor. These favorable membrane-controlled kinetics impart a gradual onset of vasodilation and a long duration of action. Further, the unique pharmacokinetic and pharmacodynamic properties of lercanidipine appear to contribute to its efficacy and favorable safety profile. In clinical trials in the treatment of mild-to-moderate hypertension, lercanidipine was administered at a starting dose of 10 mg once daily, and increased to 20 mg once daily for nonresponders. Studies have shown that lercanidipine has a 24-hour antihypertensive effect and causes no significant increase in heart rate. Lercanidipine has been shown to be effective in a wide range of hypertensive patients, including mild-to-moderate hypertension, severe hypertension, the elderly, and those with isolated systolic hypertension. It is associated with a low rate of adverse events. Because of its efficacy and favorable safety profile, lercanidipine has the potential to improve blood pressure control in a wide range of patients, including those who have not responded to, or who have been unable to tolerate, other antihypertensive agents.

Electrophysiologic effects of lercanidipine on repolarizing potassium currents

Blockade of cardiac repolarizing potassium channels by drugs may result in QT-interval prolongation, eventually degenerating into "torsades de pointes," a life-threatening arrhythmia. Lercanidipine (LER) is a recently introduced lipophilic calcium antagonist with no cardiodepressant activity and long-lasting antihypertensive action. Its chemical structure is characterized by the presence of a diphenylpropylaminoalkyl group, which is present in some of the drugs that have been reported to cause QT-interval prolongation. Our previous data demonstrated that LER blocks L-type calcium channels without affecting sodium current; however, no data are available concerning its effects on cardiac potassium channels. Transient outward (I(to)), delayed rectifier (I(K)), background currents, and action potential (AP) profile were measured from patch-clamped ventricular myocytes isolated from rat, guinea pig, or human hearts using enzymatic dissociation procedures. LER did not affect I(K) (and I(Kr)) density and activation curve in guinea pig myocytes; the reversal potential of the background current (I(K1)) and its slope were not changed by the drug. Maximal diastolic potential (MDP) and duration of the AP measured at -60 mV (APD(-60)) were not significantly changed. I(to) density and activation curves measured in rat myocytes were similar in the absence and presence of 1 or 10 microM LER. Finally, the effect of LER was tested in human ventricular myocytes: superfusion with 1 microM LER did not affect MDP and APD(-60). I(to) density and the midpoint of activation and inactivation curves were similar in the absence and presence of LER. In conclusion, our data demonstrate that LER does not affect repolarizing potassium currents and action potential profile recorded from guinea pig, rat, and human ventricular myocytes. It is unlikely that LER could cause QT prolongation in vivo.

Effect of lercanidipine and its (R)-enantiomer on atherosclerotic lesions induced in hypercholesterolemic rabbits

The in vivo antiatherogenic activity of the calcium antagonist lercanidipine and its (R)-enantiomer was investigated in two different types of atherosclerotic lesions (hyperplastic and fatty-streak lesions) in rabbits. Lercanidipine (0.3, 1, and 3 mg kg(-1) week(-1)) as well as its (R)-enantiomer at 3 mg kg(-1) week(-1) were given by subcutaneous injection for 10 weeks to White New Zealand rabbits, with cholesterol feeding beginning at week 2. The hyperplastic lesion was obtained by positioning a hollow silastic collar around one carotid artery, while aortic fatty streak lesions were induced by cholesterol feeding. In untreated animals (n=5), 14 days after collar positioning an intimal hyperplasia was clearly detectable: the arteries without collar showed a intima/media (I/M) ratio of 0.03+/-0.02, whereas in carotids with a collar the ratio was 2+/-0.42. In lercanidipine-treated animals a significant and dose-dependent effect on intimal hyperplasia was observed. I/M ratios were 0.73+/-0.4, 0.42+/-0.1, 0.32+/-0.1 for 0.3, 1, and 3 mg kg(-1) week(-1), respectively (P<0.05). The lercanidipine enantiomer (3 mg kg(-1) week(-1)) was as effective as the racemate (0.41+/-0.11). Proliferation of smooth muscle cells, assessed by incorporation of BrdU into DNA, was reduced by about 50%, 70%, 85%, and 80% by lercanidipine (0.3, 1, and 3 mg kg(-1) week(-1)) and its (R)-enantiomer, respectively. The area of fatty-streaks in the aorta (n = 11-15) was significantly reduced by lercanidipine (3 mg kg(-1) week(-1), 16% vs 27%, P<0.05), a trend was observed also with lower doses. When different segments of the aorta were considered (arch, thoracic, abdominal) a significant and dose-dependent effect in the thoracic and abdominal aorta was observed also at lower doses. The (R)-enantiomer was as effective as lercanidipine. These results suggest a direct antiatherosclerotic effect of lercanidipine, independent of modulation of risk factors such as hypercholesterolemia and/or hypertension as demonstrated by the absence of stereoselectivity.