Double-blind, dose-response, placebo-controlled multicenter study of nisoldipine. A new second-generation calcium channel blocker in angina pectoris

Efficacy and Safety of a Metabolic Modulator Drug in Chronic Stable Angina: Review of Evidence from Clinical Trials

A number of newer antianginal agents, including nicorandil, trimetazidine, and ivabradine, have been synthesized in recent years, but ranolazine, a piperazine derivative that partially inhibits fatty acid oxidation and the late INa current in animal models, is of particular interest mechanistically. Earlier clinical trials with immediate-release ranolazine led to the current sustained-release version tested in the Monotherapy Assessment of Ranolazine In Stable Angina (MARISA) (n = 193) and Combination Assessment of Ranolazine In Stable Angina (CARISA) trials (n = 823) of patients with chronic angina and severe limitation of exercise capacity (ie, < 5 metabolic equivalents). MARISA was a placebo-controlled, randomized trial that compared ranolazine monotherapy (500 mg, 1000 mg, and 1500 mg, twice daily) to placebo. CARISA was a placebo-controlled trial that randomized patients on background 1-blocker or calcium antagonist therapy to placebo or ranolazine (750 mg or 1000 mg, twice daily). Both studies showed a significant increase in total exercise duration, time to angina onset, and time to 1 mm ST segment depression. The average magnitude of increase in exercise duration over placebo was 29 to 56 seconds at peak and 24 to 46 seconds at trough with the 3 doses tested in MARISA, and 24 to 34 seconds greater than placebo with the 2 doses used in CARISA. The beneficial effect was achieved without clinically important changes in rest or exercise heart rate or blood pressure. Weekly angina attack frequency and nitroglycerin usage were significantly reduced in a dose-dependent manner in the 12-week CARISA trial. Reported adverse effects were similar in MARISA and CARISA and consisted of asthenia, nausea, constipation, and dizziness. Syncope, reported in 8 patients at doses of 1000 mg twice daily or more may be related to attenuation of α-1 receptor activity. The mean QTc interval increased with dose and was less than 10 msec on ranolazine at 1000 mg twice daily. The mortality rates at 1 and 2 years in MARISA and CARISA open-label run-on studies were 2% and less than 5%, acceptable for this high-risk population with limited exercise capacity. In conclusion, clinical trial evidence with ranolazine to date is consistent with its proposed mechanism of action and demonstrates an effective antianginal profile that may benefit patients with severe chronic angina.

A randomized, placebo-controlled study of the effects of telcagepant on exercise time in patients with stable angina

Telcagepant is a calcitonin gene-related peptide (CGRP) receptor antagonist being evaluated for acute migraine treatment. CGRP is a potent vasodilator that is elevated after myocardial infarction, and it delays ischemia during treadmill exercise. We tested the hypothesis that CGRP receptor antagonism does not reduce treadmill exercise time (TET). The effects of supratherapeutic doses of telcagepant on TET were assessed in a double-blind, randomized, placebo-controlled, two-period, crossover study in patients with stable angina and reproducible exercise-induced angina. Patients received telcagepant (600 mg, n = 46; and 900 mg, n = 14) or placebo and performed treadmill exercise at T(max) (2.5 h after the dose). The hypothesis that telcagepant does not reduce TET was supported if the lower bound of the two-sided 90% confidence interval (CI) for the mean treatment difference (telcagepant-placebo) in TET was more than -60 s. There were no significant between-treatment differences in TET (mean treatment difference: -6.90 (90% CI: -17.66, 3.86) seconds), maximum exercise heart rate, or time to 1-mm ST-segment depression using pooled data or with stratification for dose.

Efficacy and Tolerability of Nisoldipine Coat-Core vs Diltiazem Retard in Combination with a Beta-Blocker in Patients with Stable Exertional Angina Pectoris

A randomised, double-blind, placebo-controlled, parallel-group trial with forced titration study to investigate possible equivalence of efficacy and tolerability between nisoldipine coat-core (CC) 40mg once daily, and diltiazem retard 120mg twice daily, was carried out in 176 patients with stable angina pectoris who were already receiving beta-blocker therapy. A total of 164 patients were included in the tolerability analysis and 135 patients were evaluable for efficacy (nisoldipine CC, n = 69; diltiazem retard, n = 66). During bicycle exercise tolerance tests, time to 1mm ST-segment depression, total exercise time, and time to angina were assessed at baseline and at the end of the treatment period. The number of angina attacks and of consumed nitroglycerin tablets were recorded in weekly diaries. Time to onset of 1mm ST-segment depression increased by 69.4 +/- 100.0 seconds with nisoldipine CC and by 65.9 +/- 87.6 seconds with diltiazem retard. The two treatment regimens were equally effective in time to onset of 1mm ST-segment depression, time to angina pectoris, and in exercise duration. A beneficial effect on angina attacks and nitroglycerin consumption was achieved with both treatments. Patient compliance, as assessed by the number of returned tablets, was high, at over 80%. Six patients withdrew from the treatment because of adverse events. Mild and transient adverse events were reported by 24 patients during treatment. One patient experienced a severe circulatory shock on the combination of diltiazem retard and atenolol. Peripheral oedema and headache were more common on nisoldipine CC. We concluded that the two treatments were equally efficacious and tolerated in patients with stable angina pectoris.

A randomized, double-blind comparison of lercanidipine 10 and 20 mg in patients with stable effort angina: clinical evaluation of cardiac function by ambulatory ventricular scintigraphic monitoring

We evaluated the antiischemic action and the effects on left ventricular response to exercise of lercanidipine, a long-acting dihydropyridine calcium antagonist, in 23 patients with stable effort angina in a randomized, double-blind, parallel trial. Left ventricular function was assessed during upright bicycle exercise using an ambulatory radionuclide detector for continuous noninvasive monitoring of cardiac function. Exercise was performed under control conditions before (run-in placebo period) and after 2-week treatment with lercanidipine 10 or 20 mg once daily. During the placebo run-in period and at the study end, patients underwent clinical examination, ECG, exercise tests, ambulatory ventricular scintigraphic monitoring (VEST). Results showed that both drug doses increased time to onset of ST segment depression >/=1 mm and peak ST segment depression, with improvement of total exercise duration. Heart rate, blood pressure, and the rate-pressure product did not significantly change with respect to pretreatment value. The left ventricular ejection fraction, indicating contractility state of myocardium, was unchanged at rest and during exercise after both lercanidipine doses. In conclusion, lercanidipine is safe and effective in reducing ischemia in patients with stable effort angina without any deterioration of cardiac function.

De la première à la quatrième génération de dihydropyridines : vers une meilleure efficacité et une meilleure tolérance

Dihydropyridines are among the most widely used drugs for the management of cardiovascular disease. Introduced in the 1960s, dihydropyridines have undergone several changes to optimise their efficacy and safety. Four generations of dihydropyridines are now available. The first-generation (nicardipine) agents have proven efficacy against hypertension. However, because of their short duration and rapid onset of vasodilator action, these drugs were more likely to be associated with adverse effects. The pharmaceutical industry responded to this problem by designing slow-release preparations of the short-acting drugs. These new preparations (second generation) allowed better control of the therapeutic effect and a reduction in some adverse effects. Pharmacodynamic innovation with regard to the dihydropyridines began with the third-generation agents (amlodipine, nitrendipine). These drugs exhibit more stable pharmacokinetics, are less cardioselective and, consequently, well tolerated in patients with heart failure. Highly lipophilic dihydropyridines are now available (lercanidipine, lacidipine). These fourth-generation agents provide a real degree of therapeutic comfort in terms of stable activity, a reduction in adverse effects and a broad therapeutic spectrum, especially in myocardial ischaemia and potentially in congestive heart failure.

Calcium antagonists "some agents lower blood pressure and still put the heart at risk"?

The 1,4 dihydropyridine calcium antagonists have several properties that theoretically make them attractive for treatment of hypertension and prevention as well as management of coronary artery disease (CAD). However, some of them appear to have actions that are detrimental for outcome. This brief review will first address the different subclasses of dihydropyridines, then outline differences between these subclasses which may impact on outcome in CAD and hypertension, and the last part will review present evidence for differences in cardiac outcome.

Cardiovascular disease in women: gender-specific aspects of hypertension and the consequences of treatment

The epidemiology, clinical course, response to treatment, and ultimate outcome of essential hypertension vary as a function of gender. Three early trials on hypertension reported an increase in all-cause mortality in treated white women compared with black women or with men of both races. Later studies, however, suggest that drug therapy has similar and beneficial effects in hypertensive men and women. Women may tolerate hypertension better than do men. Diastolic hypertension correlates with higher mortality from coronary artery disease in men than in women. Special considerations apply to treating the hypertensive woman. Use of oral contraceptives may precipitate or accentuate the problem. In contrast, in the postmenopausal female, estrogen replacement may actually improve hypertension, via several mechanisms. These include the impact of the hormone on vasomotricity, its enhancement of baroreceptor sensitivity, and its impact on the hyperinsulinemia characteristic of menopause. Treatment of hypertension must be individualized with respect to gender. More data on the consequences of treatment of women with hypertension are needed, particularly longterm studies to assess the impact of treatment on mortality.

Dynamic stress echocardiography for evaluating anti-ischemic drug profiles in post-MI patients

Exercise ECG is an established method of evaluating the anti-ischemic properties of drugs. However, there are considerable methodologic limitations to this procedure and its use is restricted to patients with exercise-provoked ECG alterations which can be interpreted as ischemia. The principal, earlier onset of wall motion abnormalities according to the ischemic cascade can be detected by stress echocardiography and might be utilized as a pharmacological stress testing modality. Sixteen consecutive patients (15 men, one woman; 53 +/- 9 years old) with angiographically proven coronary artery disease (8 with one-, 5 with two-, and 3 with three-vessel disease) and exercise-induced wall motion abnormalities were examined by dynamic stress echocardiography (50 watt followed by 20-watt increases/min). Anti-ischemic drugs were withdrawn prior to and on day 1; on the following day 2, 0.2 microgram/kg/min nisoldipine was infused intravenously during the test after a 3 micrograms/kg bolus was given. At maximum comparable workload 15/16 patients showed an improved wall motion score on treatment (day 1: 22.9 +/- 4.9 vs day 2: 20.0 +/- 3.9; normal score: 12; one-sided binomial test: p = 0.0003). Eight of 16 patients demonstrated ST-segment deviations on day 1 and day 2. The double product did not differ at any workload stage until the maximum of 130 watt (day 1: 14,101 +/- 3140 vs day 2: 13,365 +/- 2865; n.s.). Dynamic stress echocardiography seems to be a valuable tool in pharmacologic stress testing and in terms of accuracy is supposed to be superior to conventional exercise ECG. Nisoldipine reduces exercise-induced wall motion abnormalities in patients with and without exercise-induced ECG alterations. The data result from a controlled pilot study, and further studies are required to confirm these promising methodological and therapeutic findings.

Clinical implications of the World Health Organization-International Society of Hypertension statement on calcium antagonists

The controversy over the efficacy and safety of calcium antagonists is over 2 years old. Since millions of patients worldwide are currently using calcium antagonists for the treatment of high blood pressure and angina, a systematic review of their potential risks and benefits is much needed. In response to this need, the World Health Organization (WHO) and the International Society of Hypertension (ISH) recently convened an ad-hoc subcommittee to review the available evidence (J Hypertens 1997, 15:105-115). Importantly, the WHO-ISH statement does take a strong stand in favor of large long-term trials that compare antihypertensive agents, and we all agree that these comparative trials are urgently needed. However, the WHO-ISH statement is marred in part by errors of omission, by the selective use of evidence and epidemiologic principles, and by a narrow application of the viewpoint of those who believe that evidence can come only from the results of megatrials. As a result, practicing clinicians will find more useful information in existing hypertension and postmyocardial infarction guidelines (Arch Intern Med 1993, 153:154-183 and JAm Coll Cardiol 1996, 28:1328-1428).

Nisoldipine coat-core. A review of its pharmacodynamic and pharmacokinetic properties and clinical efficacy in the management of ischaemic heart disease

Nisoldipine coat-core is an extended-release once-daily formulation of a dihydropyridine calcium antagonist effective in the treatment of chronic stable angina pectoris. With immediate-release formulations of nisoldipine, plasma drug concentrations that produce therapeutic effects result rapidly, but are not sustained and do not maintain the effects throughout a 12-hour dosage interval. In contrast, with nisoldipine coat-core, a gradual increase in plasma nisoldipine concentrations occurs over 12 hours and therapeutic concentrations are then maintained for the duration of a 24-hour dosage interval. In dosages of 10 to 60 mg once daily, nisoldipine coat-core controls symptoms of angina and improves exercise-induced signs of ischaemia in patients with stable angina. Compared with placebo, daily nisoldipine coat-core doses of > or = 20 mg provide statistically significant increases in total exercise time and time to produce angina and a trend towards an increase in the time to produce 1 mm ST segment depression, in exercise tests conducted approximately 23 hours postdose. When administered in 20 and 40 mg daily doses, nisoldipine coat-core produces improvements in exercise test parameters that are similar to those seen with amlodipine 5 or 10 mg/day or regular-release or sustained-release (SR) diltiazem 240 mg/day. The frequency of daily angina attacks and consumption of short-acting nitrates are also reduced by nisoldipine to a similar extent to that observed with these other agents. After longer term (1 year) administration of 10 to 60 mg daily, improvements in exercise test parameters are maintained, with equivalent anti-ischaemic efficacy seen in patients receiving nisoldipine coat-core alone or with background nitrate or beta-blocker therapy. Adverse events associated with nisoldipine coat-core are typical of the dihydropyridine class of calcium antagonists, with peripheral oedema and headache being most common. Nisoldipine coat-core appears to be associated with fewer deaths than placebo, notably in the DEFIANT-II (Doppler Flow and Echocardiography in Functional Cardiac Insufficiency: Assessment of Nisoldipine Therapy II) study, where only 1 death occurred with nisoldipine compared with 7 in the placebo group. Nisoldipine should not be taken during phenytoin therapy. In addition, grapefruit juice should be avoided during nisoldipine therapy and nisoldipine should not be taken concurrently with high-fat meals. Thus, the coat-core formulation of nisoldipine appears to have overcome the limitations of the shorter duration of action of immediate-release nisoldipine. Nisoldipine coat-core is well tolerated and once-daily administration produces a long duration of effective anti-ischaemic relief in patients with chronic stable angina pectoris.

Felodipine and amlodipine in stable angina pectoris: results of a randomized double-blind crossover trial

A randomized, double-blind, crossover study tested the antiischemic and antianginal efficacy of felodipine, extended-release 5-10 mg, versus amlodipine, 5-10 mg once daily. Fifty-two patients with documented exercise-induced angina pectoris and myocardial ischemia during 24-h electrocardiographic monitoring were included in the study. Forty-seven patients completed the 8-week treatment period, whereas five patients withdrew from the study. The mean number of ischemic episodes/24 h was reduced from 19.9 at baseline to 2.3 during amlodipine and to 2.4 during felodipine; the total duration of ischemic episodes decreased from 69.8 min/24 h to 15.2 min and 15.5 min during amlodipine and felodipine, respectively (for both variables, p = 0.83 and p = 0.53 between treatments, and for both treatments, p < 0.001 compared with baseline). Eighteen (38%) patients receiving amlodipine and 19 (40%) patients receiving felodipine showed no ST-segment depression during treatment. Maximal ST-depression was reduced from an average of 2.1 mm to 1.1 and 1.2 mm on amlodipine and felodipine, respectively (p = 0.68 between treatments and p < 0.001 compared with baseline). Mean heart rate remained unchanged compared with baseline. Anginal attacks were reduced from 16.4/week at baseline to 4.7/week with amlodipine and to 4.3/week with felodipine (p = 0.26 between treatments, and p < 0.001 vs. baseline). Accordingly, nitrate consumption was reduced from 14.7 capsules per week to 4.0 and 3.8 with amlodipine and felodipine, respectively (p = 0.40 between treatments, and p < 0.001 compared with baseline). Adverse reactions were infrequent and distributed similarly between the two treatments. It is concluded that both drugs effectively reduced ischemic episodes and anginal attacks and were well tolerated in patients with stable angina pectoris. There was no evidence that the two regimens were different in their antiischemic and antianginal properties.

Calcium antagonists in patients with left ventricular dysfunction: back on the bridge?

Calcium antagonists have a useful role in the management of patients with cardiac disease, producing coronary and systemic vasodilatation and an additional possibly beneficial effect on ventricular diastolic function. On the other hand, the myocardial depressant effect of the first-generation drugs and the abrupt changes in blood pressure, with neurohormonal activation, have been associated with worsening heart failure in certain patients. The present review summarizes the data currently available, with emphasis on the newer slow-release and long-acting calcium antagonists. Use of these drugs minimizes the peak and trough effect associated with short-acting preparations, and particularly when administered against a background of digoxin, diuretic and angiotensin converting enzyme inhibitors, may be associated with better long-term results in patients with ventricular dysfunction. The DEFIANT studies, using nisoldipine-coat core, showed that nisoldipine-CC improved diastolic ventricular function and had a significant anti-ischemic effect in patients with mild-moderate ventricular dysfunction after acute myocardial infarction. The VHeFT III trial showed that felodipine had no effect on exercise capacity or survival in patients with Class 2-3 heart failure. In the PRAISE study of Class 3-4 patients, amlodipine was neutral in patients with ischemic disease, but a strikingly beneficial effect was observed in non-ischemic heart failure (45% decrease in mortality). The precise mechanism for the beneficial effect of amlodipine in these patients is unknown. Further studies are needed to examine the issue of survival benefit in patients with non-ischemic heart failure and the mechanisms involved.

Should calcium antagonists be first-line agents in the treatment of cardiovascular disease? The public health perspective

The calcium antagonist (CA) controversy has been fueled in part by disagreements among scientists and clinicians over the scientific documentation required for drugs used to treat lifelong conditions. From a public health perspective, there are three unanswered questions: (1) Does long-term use of CAs convey health benefits to patients with cardiovascular disease (CVD)? (2) Is the long-term use of CAs safe? (3) Is the use of CAs cost effective? The answers to these questions determine the pertinence of three secondary questions: (4) Do the effects of CAs reflect a class action or are there important differences in health outcomes among subclasses of CAs? (5) Are the short-acting, immediate-release (IR) formulations different from the long-acting or the slow-release (SR) formulations? (6) What is prudent use of CAs? The purpose of this report is to summarize the answers to these questions from a public health perspective. (1) To date, use of CAs has not been documented to reduce the risks of cardiovascular complications of hypertension-stroke, myocardial infarction, congestive heart failure, or renal dysfunction. (2) The clinical trial database is inadequate to determine the long-term safety of CAs. The available data suggest that some formulations of CAs may be associated with an increased risk of cardiovascular and noncardiovascular events. (3) Even if slow-release CAs conveyed a benefit, their cost-effectiveness ratios are unlikely to be acceptable. (4) The non-dihydropyridines may offer an advantage over the dihydropyridines. (5) Whether the slow-release formulations differ from the immediate-release formulations in terms of their health effects remains to be seen. (6) It may be prudent clinically to restrict the use of CAs until proper documentation of long-term safety and efficacy and cost effectiveness is available.

Anti-ischemic intervention as prognosis improvement in patients with coronary artery disease, with special focus on verapamil

Angina pectoris is a significant risk predictor in patients with atherosclerotic heart disease. The major complications are myocardial infarction, heart failure, and arrhythmias. Plaque rupture turns stable angina pectoris into acute coronary syndrome by provoking platelet aggregation and thereby thrombus formation. Verapamil significantly inhibits platelet aggregation and thrombus formation, which may be one of several reasons for the protective effect of verapamil on reinfarction in patients recovering from myocardial infarction. Ischemia may lead to left ventricular dilation and diastolic dysfunction, and thereby heart failure. In postinfarction patients intervention with verapamil significantly reduced the use of diuretics compared with placebo, indicating that anti-ischemic intervention may prevent heart failure. Ventricular arrhythmias are significantly associated with arrhythmic as well as non-arrhythmic death. The lack of preferential association of ventricular arrhythmias with arrhythmic death rather than nonarrhythmic death may imply that arrhythmias are provoked by ischemia. Antiarrhythmic intervention in postinfarction patients significantly increases death and arrhythmic events compared with placebo, especially in patients with residual ischemia. This may be due to a significant slowing of conduction during ischemia in patients treated with antiarrhythmic agents. In animal studies anti-ischemic agents prevent or suppress ventricular arrhythmias during ischemia, whereas traditional antiarrhythmic drugs have no effect or even worsen the arrhythmias, especially during episodes with elevated sympathetic activity. Verapamil significantly reduces plasma norepinephrine levels and the norepinephrine release during ischemia, whereby ventricular arrhythmias may be prevented. Also, supraventricular arrhythmias are significantly associated with myocardial ischemia and are prevented by verapamil. In patients with atherosclerotic heart diseases, angina pectoris is a significant risk predictor, but anti-ischemic intervention should be considered even in patients in whom the major problem is heart failure or arrhythmias.

Combination therapy with metoprolol and nifedipine versus monotherapy in patients with stable angina pectoris. Results of the International Multicenter Angina Exercise (IMAGE) Study

OBJECTIVES

This study was designed to investigate whether combination therapy with metoprolol and nifedipine provides a greater anti-ischemic effect than does monotherapy in individual patients with stable angina pectoris.

BACKGROUND

Combination therapy with a beta-adrenergic blocking agent (which reduces myocardial oxygen consumption) and a dihydropyridine calcium antagonist (which increases coronary blood flow) is a logical approach to the treatment of stable angina pectoris. However, it is not clear whether, in individual patients, this combined therapy is more effective than monotherapy.

METHODS

Two hundred eighty patients with stable angina pectoris were enrolled in a double-blind trial in 25 European centers. Patients were randomized (week 0) to metoprolol (controlled release, 200 mg once daily) or nifedipine (Retard, 20 mg twice daily) for 6 weeks; placebo or the alternative drug was then added for a further 4 weeks. Exercise tests were performed at weeks 0, 6 and 10.

RESULTS

At week 6, both metoprolol and nifedipine increased the mean exercise time to 1-mm ST segment depression in comparison with week 0 (both p < 0.01); metoprolol was more effective than nifedipine (p < 0.05). At week 10, the groups randomized to combination therapy had a further increase in time to 1-mm ST segment depression (p < 0.05 vs. placebo). Analysis of the results in individual patients revealed that 7 (11%) of 63 patients adding nifedipine to metoprolol and 17 (29%) of 59 patients (p < 0.0001) adding metoprolol to nifedipine showed an increase in exercise tolerance that was greater than the 90th percentile of the distribution of the changes observed in the corresponding monotherapy + placebo groups. However, among these patients, an additive effect was observed only in 1 (14%) of the 7 patients treated with metoprolol + nifedipine and in 4 (24%) of the 17 treated with nifedipine + metoprolol.

CONCLUSIONS

The mean additive anti-ischemic effect shown by combination therapy with metoprolol and nifedipine in patients with stable angina pectoris is not the result of an additive effect in individual patients. Rather, it may be attributed to the recruitment by the second drug of patients not responding to monotherapy.

Calcium channel antagonists in the treatment of coronary artery disease: fundamental pharmacological properties relevant to clinical use

Calcium channel antagonists are a diverse group of drugs with clinical antianginal and antihypertensive properties. They have as a common property the capacity to lessen the rate of calcium ion entry through a specific type of calcium channel, namely the voltage-gated L-type channel. They do not bind to all the pore molecules; therefore, there is still some residual entry of calcium ions. Variables determining the clinical efficacy of the different drugs include the binding sites involved, the tissue specificity of the drug, the duration of action, and (closely related) the degree of counter-regulatory neurohumoral activation. Inhibitory effects on the calcium channels of vascular smooth muscle explain the antihypertensive effect and the reduction of afterload, one of the antianginal mechanisms common to all of the drugs. In general, the dihydropyridines, such as nifedipine, are more vascular-selective than the non-dihydropyridines, such as verapamil and diltiazem. The latter owe part of their antianginal activity to more prominent effects on the calcium channels in the sinoatrial node (decreased heart rate) and the myocardium (negative inotropic effect). In addition, calcium channel antagonists are coronary artery vasodilators. Whether the latter effect confers on these drugs any specific advantage in the therapy of anginal syndromes is controversial.

Nifedipine gastrointestinal therapeutic system (GITS). A review of its pharmacodynamic and pharmacokinetic properties and therapeutic efficacy in hypertension and angina pectoris

Nifedipine 'gastrointestinal therapeutic system' (GITS) is a recently developed formulation that slowly releases the drug into the intestinal tract over a 24-hour period. When administered once daily, it is of similar efficacy to sustained release formulations of felodipine, verapamil, and diltiazem and at least as effective as standard formulations of lisinopril and enalapril, and long-acting propranolol and atenolol in the treatment of patients with mild to moderate essential hypertension. Substitution of nifedipine GITS for conventional formulations of nifedipine, diltiazem or verapamil, maintained adequate control of anginal symptoms in patients with stable angina pectoris. Nifedipine GITS appears to maintain quality of life and is apparently better tolerated than those formulations of nifedipine which require 2 or 3 times daily administration in both elderly and younger patients. In addition, it has minimal effect on lipid and glucose metabolism and reverses left ventricular hypertrophy, and is thus suitable for treatment of the majority of patients with mild to moderate hypertension or angina pectoris.

Antianginal and antiischemic efficacy of monotherapy extended-release nisoldipine (Coat Core) in chronic stable angina

A double-blind, randomized, placebo-controlled study was conducted to test the peak and trough antianginal and antiischemic monotherapy efficacy and safety of a new extended-release formulation of nisoldipine (nisoldipine Coat Core [Bayer Corporation], 20 mg, 40 mg, and 60 mg once daily compared to placebo). Study patients had a history of chronic, stable angina pectoris, exercise-induced angina in association with ST segment depression, and exercise test reproducibility. Of the 483 patients enrolled in the study, results were valid for safety analysis for 312 and for efficacy analysis for 284. There was a statistically significant improvement in total exercise time at both peak and trough for patients taking 20 mg and 60 mg of nisoldipine compared with patients taking placebo, but the group taking 60 mg was not better than the group taking 20 mg (33.9 and 33.7 seconds, respectively, at trough). The results were similar for the secondary endpoints (time to onset of angina and time to 1 mm ST segment depression). No correlation was evident between plasma nisoldipine levels and total exercise duration. Headache and peripheral edema were the most frequently reported adverse events and were dose related. There were no discontinuations due to adverse events in patients randomized to the 20-mg nisoldipine group. No deaths occurred while patients were receiving active nisoldipine therapy. Therapy with this extended-release formulation of nisoldipine is an effective once-daily treatment for chronic stable angina pectoris. It represents one of the few dihydropyridine calcium channel antagonists that has shown efficacy when administered as monotherapy to patients with angina.

Nisoldipine coat core as concomitant therapy in chronic stable angina pectoris

Nisoldipine is a second-generation dihydropyridine calcium antagonist that has been extensively studied as an antianginal and antihypertensive agent. As an antianginal agent, the immediate release formulation has shown significant activity at peak effect but less at trough. As a result, a sustained release formulation (coat core) has been developed. This report focuses on the studies evaluating the antianginal and anti-ischemic effects of nisoldipine coat core (NIS CC) when used alone or with add-on therapy with beta-adrenergic blocking agents and/or long-acting nitrates (3 long-term extension trials), or as add-on therapy to existent beta-adrenergic blocking treatment (in 1 double-blind, short-term trial). The long-term extension studies all demonstrated an improvement in exercise test variables and a reduction in angina frequency and sublingual nitroglycerin usage with NIS CC when compared with baseline. Discontinuation due to ischemic adverse events occurred in 5.4-13.6% of patients during the 1-year course of these trials. However, only 2 deaths and 9 myocardial infarctions occurred (in 503 patients enrolled and 342 patients completing the entire 1 year of therapy). The short-term, double-blind study evaluated the addition of NIS CC (20 or 40 mg vs placebo) to existent atenolol therapy (50 mg four times daily). Exercise test variables at peak and trough showed a trend toward improvement, although these changes did not reach statistical significance. Other support for the efficacy of NIS CC was also demonstrated, and double-blind studies with the immediate release formulation have also shown improvements when nisoldipine was utilized as add-on therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Efficacy and safety of nisoldipine coat core in the management of angina pectoris, systemic hypertension, and ischemic ventricular dysfunction

The effects of the long-acting dihydropyridine calcium antagonist nisoldipine coat core (CC) have been investigated in > 3,500 patients with angina pectoris, hypertension, and ischemic ventricular dysfunction. In patients with angina pectoris, nisoldipine CC improved total treadmill exercise duration (p = 0.027), delayed the onset of angina pectoris (p = 0.009), and increased time to exercise-induced ST-segment depression (p = 0.061). In general, nisoldipine 20-40 mg was effective, and the dose-response curve flattened thereafter. In patients with hypertension, 10-40 mg once daily as monotherapy reduced blood pressure (p < 0.05), with a fall in diastolic pressure of > or = 10 mm Hg or a final diastolic pressure of < 90 mm Hg in 35-63% of patients. In most patients followed for a year, nisoldipine CC was continued as monotherapy. Efficacy was similar in patients < 65 and > 65 years of age. In the Doppler Flow and Echocardiography in Functional Cardiac Insufficiency: Assessment of Nisoldipine Therapy (DEFIANT-I) study of patients recovering from myocardial infarction, nisoldipine CC had a salutary effect on diastolic ventricular function, with a higher transmitral early filling velocity and shorter isovolumic relaxation time than in patients receiving placebo. Bicycle exercise capacity was greater (by 12 W; 95% confidence interval, 0.8-23.3) and exercise-induced ischemia occurred less frequently. The nisoldipine CC data pool (3,679 patients) showed that the drug was well tolerated with a low incidence of side effects.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparison of efficacy of nisoldipine, metoprolol, and isosorbide dinitrate in patients with stable exertional angina: a randomized, cross-over, placebo-controlled study

We evaluated the acute antianginal effect of oral nisoldipine (10 mg), metoprolol (40 mg), and long-acting isosorbide dinitrate (20 mg) in 15 patients with stable exertional angina. The patients performed symptom-limited treadmill exercise at 2 h after the administration of placebo (Placebo stages 1 and 2) and each of the active drugs. After Placebo stage 1, the patients were randomized for cross-over evaluation of the acute effect of a single oral dose of placebo (Placebo stage 2), nisoldipine, metoprolol, or long-acting isosorbide dinitrate. All 15 patients developed angina during all of exercise tests and their exercise tests were terminated at the onset of angina. The time until development of 0.1 mV ST segment depression was increased by all three drugs compared to placebo, and it was significantly longer with metoprolol than with isosorbide dinitrate. Similarly, the time to ceasing exercise because of angina was also prolonged by all three drugs. The exercise time was longer with nisoldipine and metoprolol compared to isosorbide dinitrate, but there was no significant difference between nisoldipine and metoprolol. In conclusion, metoprolol and nisoldipine more effectively prolonged exercise compared to long-acting isosorbide dinitrate in patients with stable exertional angina.

Antianginal and anti-ischemic efficacy of immediate-release nisoldipine in chronic stable angina pectoris

A double-blind, randomized, placebo-controlled, crossover study tested peak and trough efficacy of immediate-release nisoldipine (20 mg twice daily) added to existent beta-adrenergic blocking therapy. Patients were randomized with a history of chronic stable angina, while receiving a stable regimen of a beta-blocking agent, with exercise test-induced angina in association with 1 mm horizontal or downsloping ST-segment depression and exercise test reproducibility of +/- 15%. Ambulatory electrocardiographic monitoring (48-hour) was performed at 3 of 5 centers (44 patients). Efficacy was achieved in 53 patients (26 taking immediate-release nisoldipine/placebo in sequence and 27 taking placebo/immediate-release nisoldipine in sequence). Total exercise time increased compared with placebo at peak, but only a trend was seen at trough. Time to 1 mm ST-segment depression at peak and trough and ambulatory electrocardiographic parameters were also improved. Adverse effects were mild. This trial confirms that immediate-release nisoldipine when added to existent beta-blocker therapy is an active antianginal and anti-ischemic agent, but that the immediate-release formulation loses its antianginal effect at the end of its dosing interval (9 to 14 hours). This drug is therefore being examined in a new extended-release formulation (Coat-Core).

The DEFIANT study of left ventricular function and exercise performance after acute myocardial infarction. Doppler Flow and Echocardiology in Functional Cardiac Insufficiency: Assessment of Nisoldipine Therapy Study Group

The DEFIANT-I study (Doppler Flow and Echocardiography in Functional cardiac Insufficiency: Assessment of Nisoldipine Therapy) was a multicenter, multinational double-blind randomized study of the effects of the new calcium channel blocking drug nisoldipine on left ventricular (LV) size and function after acute myocardial infarction. Randomization to placebo or to long-acting nisoldipine core coat (20 mg once daily) was performed in 135 eligible patients with mild to moderate systolic LV dysfunction (LV ejection fraction < or = 50%) 20 days (range 7-35) after infarction, with serial clinical, echocardiographic, and Doppler cardiographic measurements during a 4 week follow-up period. At the end of the follow-up period, exercise capacity was determined by bicycle ergometry. Nisoldipine improved indices of diastolic LV function. Early diastolic transmitral blood flow velocity increased, with an increase in peak E wave of 0.06 m/sec (95% confidence intervals [CI], 0.01, 0.11) and an increase in time velocity integral of 1.2 cm (95% CI, 0.16, 2.27). Isovolumic relaxation time was reduced by 14.7 msec (95% CI, -22.5, -6.9), a change not explained by the very small (and not significant) changes in systemic arterial pressure, heart rate, or cardiac output. There was no change in systolic and diastolic LV volume, nor in LV ejection fraction. Exercise capacity was greater by 12 watts (95% CI, 0.8, 23.3) in patients receiving nisoldipine, while the incidence of > or = 1 mm ST-segment depression (relative occurrence 0.54, 95% CI, 0.30-0.97) and the incidence of angina pectoris (relative occurrence 0.67, 95% CI, 0.42-1.08) during exercise testing tended to be lower in this group. Although the relations were not exact, peak exercise workload 7 weeks after infarction correlated with resting measurements of diastolic LV function. Exercise workload was inversely related to peak late diastolic transmitral blood flow velocity (A wave, slope, -86.6; 95% CI, -120.9, -52.2) and directly to the E/A ratio (slope, 20.5, 95% CI, 6.0, 35.1). The relations between exercise workload and peak late diastolic flow velocity remained significant after correction for age, sex, resting heart rate, and usage of beta-blocking drugs or nisoldipine. Exercise capacity was not related to measurements of systolic LV function (LV end-diastolic and end-systolic volume, LV ejection fraction, stroke volume, cardiac index). In summary, the calcium channel blocker nisoldipine improved measurements of diastolic LV function in patients recovering from acute myocardial infarction. Exercise capacity was higher in patients receiving the drug, and there was less exercise induced ischemia.(ABSTRACT TRUNCATED AT 400 WORDS)

Duration of effects of isradipine during twice daily therapy in angina pectoris

Isradipine, a 1,4 dihydropyridine calcium channel antagonist, is a potent coronary artery dilator that increases coronary blood flow with little effect on cardiac contractility. Isradipine is an approved antihypertensive agent, but its antianginal effects have not been well documented. In this placebo-controlled, double-blind, parallel-group design study we evaluated the duration of effects and safety of isradipine 10 mg bid in male patients with chronic stable angina pectoris. Seventy-two patients experiencing moderately severe angina between 3 and 7.5 minutes during a standard Bruce exercise test received placebo in a single-blind manner for 8-14 days. Sixty-one of these patients had reproducible treadmill exercise test results on three consecutive occasions and underwent further exercise tests at 3, 8, and 12 hours after a placebo period. Patients were then randomized (double blind) to either placebo or isradipine 10 mg bid for 2 weeks. Symptom-limited exercise tests were repeated predose and at 3, 8, and 12 hours after the 0800 hour dose dosing. Exercise duration increased significantly from baseline (last qualifying test during the single-blind placebo therapy, i.e., 0800 hours predose at visit 4) in the isradipine group compared to the placebo group prior to the administration of the 0800 hour dose (i.e., 12 hours after the 2000 hour dose) by 51 vs. 18 seconds, p = 0.04; and after the administration of the 0800 hour dose at 3 hours by 78 vs. 29 seconds, p = 0.005; and at 8 hours by 54 vs. 18 seconds, p = 0.04. Similarly, statistical significance was achieved when exercise data were analyzed using visit 4 (single-blind placebo therapy) corresponding time points as baseline. At 12 hours after the 0800 hour dose, exercise tolerance did not increase significantly after isradipine compared to placebo. Time to 1-mm ST-segment depression increased significantly after isradipine at 3 hours post 0800 hour dose compared to placebo (87 vs. 7 seconds, p < 0.01) but not at the 0, 8, or 12-hour postdose time points, regardless of which baseline was used. Isradipine therapy did not affect the rate-pressure double product. A significant correlation between the mean increase in total exercise time and mean plasma isradipine concentration was also present (p = 0.0295). During double-blind treatment, drug-related adverse events were experienced by four patients in the isradipine group and two patients in the placebo group. None of the patients experienced ischemic complications during the study.(ABSTRACT TRUNCATED AT 400 WORDS)

Use of calcium channel antagonists for cardiovascular disease

Until recently, only three calcium channel antagonists--verapamil, diltiazem and nifedipine--were available for managing cardiovascular disorders such as hypertension and ischemic heart disease. In the past few years, however, several dihydropyridine calcium channel antagonists, including nicardipine, isradipine, felodipine, nimodipine, and amlodipine, have been marketed. Others are currently awaiting FDA approval. In addition, bepridil, which belongs to a new class of calcium channel antagonists, has recently been marketed for refractory angina pectoris. Clinical uses of calcium channel antagonists have been expanded since the 1970s to include management of cardiovascular disorders such as supraventricular arrhythmias, CHF secondary to diastolic dysfunction, and myocardial reinfarction in selected patients. Calcium channel antagonists are also being investigated for prevention of atherosclerosis. Calcium channel antagonists are a heterogeneous group of pharmacologic agents. Differences in tissue selectivity are largely responsible for the variations in hemodynamic and electrophysiologic properties of these agents. Thus, their clinical uses and side effect profiles differ. These differences must be taken into consideration in the selection of the most appropriate agent for a specific indication. Potential advantages of some of the newer dihydropyridine calcium channel antagonists include less frequent dosing (amlodipine and isradipine) and little or no negative inotropic effect (nicardipine, felodipine, amlodipine, isradipine) compared with the prototype calcium channel antagonists. Additional clinical experience with these newer agents is required, however, before their role in the management of cardiovascular disorders can be fully delineated. The availability of sustained-release formulations of verapamil, diltiazem, nifedipine, felodipine, and nicardipine, as well as the recent marketing of calcium channel antagonists with relatively long half-lives (amlodipine and isradipine), makes once- or twice-daily dosing possible with most calcium channel blockers. However, selection of a particular agent will depend on several factors, including clinical efficacy, side effect profile, cost, and patient characteristics such as concomitant disease states and baseline hemodynamic status.

Transient myocardial ischemia during nifedipine therapy in stable angina pectoris, and its relation to coronary collateral flow and comparison with metoprolol

There are conflicting results concerning the anti-ischemic effect of nifedipine in patients with chronic stable angina. Therefore, the purpose of this study was to assess whether the anti-ischemic effect of nifedipine may be related to coronary collateral circulation. Forty-one patients with stable angina and coronary artery disease were randomized to a parallel double-blind study with nifedipine and metoprolol, and compared for effects on transient ischemic episodes during ambulatory electrocardiographic monitoring and exercise-induced ischemia. The effects were correlated to the presence of collateral circulation. In 17 patients, angiographically poor or no collateral flow was observed (group 1), and 24 had good collateral flow (group 2). Nifedipine was administered to 20 patients (8 in group 1, and 12 in group 2). In group 1, nifedipine reduced the frequency of total and asymptomatic ischemic episodes (p < 0.05), whereas significant increases in both total (p < 0.05) and silent (p < 0.01) ischemia were observed in group 2. Exercise variables were slightly improved (p = NS) during nifedipine therapy in group 1, and slightly worsened (p = NS) in group 2. Reflex tachycardia was not observed at either the onset of transient ischemia out of the hospital or exercise-induced ischemia. This was in contrast with the effect in 21 patients treated with metoprolol (9 in group 1, and 12 in group 2) where significant reductions were observed in the frequency of both total (p < 0.01) and silent (p < 0.01) ischemia in both groups. Furthermore, a beneficial effect was observed on all exercise variables.(ABSTRACT TRUNCATED AT 250 WORDS)