Comparison of nadolol, a new long-acting beta-receptor blocking agent, and placebo in the treatment of stable angina pectoris

Glucocorticoids produced during exercise may be necessary for optimal virus-induced IL-2 and cell proliferation whereas both catecholamines and glucocorticoids may be required for adequate immune defense to viral infection

Prolonged, exhaustive exercise has been associated with impaired immune responsiveness and increased susceptibility to infection. We have shown that one bout of exercise to fatigue followed by viral challenge increases mortality. Stress hormones such as corticosteroids and catecholamines have been suggested as potential mediators of exhaustive exercise-induced immunosuppression. The purpose of this study was to determine whether the administration of pharmacological agents to block the effect of catecholamines or corticosteroids would minimize the immunosuppression associated with this type of exercise. Mice either exercised to fatigue or were exposed to control conditions, and mice received an i.p. injection of either nadolol (beta-adrenergic receptor antagonist), RU486 (glucocorticoid type II receptor antagonist), or vehicle. Fifteen minutes post-exercise, mice were exposed to viral infection (Herpes simplex virus; HSV) via an intranasal route, and cells were collected 3 days post-infection. The results showed that exercise suppressed HSV-specific cell proliferation, HSV-specific IL-2, and IFN-gamma, but did not alter these same immune parameters when the mitogen ConA was used to stimulate cells. In addition, exercise reduced NK cell cytotoxicity, alveolar cell TNFalpha, and peritoneal IL-1beta, but did not affect IL-10. The pharmacological blockade did not attenuate the exercise-associated immunosuppression. In fact, RU486 treatment exacerbated the exercise-induced decline in HSV-induced IL-2 production and cell proliferation. RU486 and nadolol treatment also tended to decrease IL-10, IFN-gamma, TNFalpha (nadolol only), and IL-1beta (RU486 only) in both exercise and control mice, suggesting that stress hormones may be necessary during infection for optimal responsiveness. These findings suggest that suppression of immune defenses during viral infection persists for at least 3 days post-exercise, and stress hormones may be essential for optimal immune defense to viral challenge, rather than detrimental.

Amlodipine combined with beta blockade for chronic angina: Results of a multicenter, placebo-controlled, randomized double-blind study

Amlodipine, a potent long-acting dihydropyridine calcium antagonist, was compared with placebo in a parallel, randomized, double-blind study in 134 patients with chronic stable angina pectoris maintained on beta-adrenergic blocking agents. After a single-blind, two-week placebo period, patients were randomized to receive either amlodipine (2.5, 5, and 10 mg) or placebo once daily for four weeks. The effects of amlodipine on maximal exercise time, work, time to angina onset, and subjective indices including angina frequency, nitroglycerin tablet consumption, and patient and investigator ratings were assessed. Each dose of amlodipine produced increases in exercise time and calculated total work accomplished compared to baseline. Improvements at 5 and 10 mg were significantly greater than placebo which produced no significant change (p less than 0.05). Qualitative improvements in the severity of angina were produced by amlodipine at 5 and 10 mg daily assessed by patient-rating questionnaires (p less than 0.05). Reductions in angina frequency attacks per week and weekly nitroglycerin tablet consumption occurred but were not statistically significant when compared with placebo. Adverse effects observed during amlodipine treatment prompted discontinuation of treatment in only 2 out of 100 patients. Three patients discontinued treatment for reported lack of efficacy. No laboratory abnormalities prompted treatment discontinuation and minor side effects of dizziness, nausea, headache, and fatigue were observed infrequently. The results of this controlled, large-scale multicenter trial suggest that amlodipine significantly increased exercise capacity and was well tolerated when added to the antianginal regimen of patients remaining symptomatic while receiving beta-blocking agents.

Comparison of the duration of action of atenolol and nadolol for treatment of angina pectoris

In a randomized, double-blind, placebo-controlled cross-over study, 16 patients with angina on effort due to proven coronary artery disease were given atenolol 50 or 100 mg and nadolol 40 or 80 mg every morning. Compared with placebo control, both beta blockers equally decreased angina frequency, suppressed supine, standing, submaximum and maximum heart rates and double products (all p less than 0.0001) and increased exercise tolerance (p less than 0.01) when the exercise stress test was done 3 to 4 hours after the daily dose. When the exercise stress test was done 24 hours after the daily dose, the suppression of resting and maximum exercise heart rates and maximum double product was more pronounced by nadolol than atenolol (p less than 0.05). Ambulatory electrocardiography heart rates were also equally suppressed by both beta blockers in the afternoon, evening and nighttime hours. However, in the hours just before and just after the ingestion of the daily dose the effect of nadolol (elimination half-life 1,436 +/- 420 minutes) was more pronounced (p less than 0.05) than that of atenolol (half-life 537 +/- 62 minutes). Negative correlations (p less than 0.03) between beta-blocker blood levels and submaximal exercise heart rates and double products were observed.

A comparison of carteolol and nadolol in the treatment of stable angina pectoris

In a multicenter, dose-ranging, double-blind study, 63 patients diagnosed as having stable angina pectoris were randomly assigned to treatment with carteolol (33 patients) or nadolol (30 patients). Following a 2 to 4-week dose-ranging period, an optimal dose was determined for each patient and treatment with that dose continued for 6 weeks. Data from all 63 patients were analyzed for drug safety; data for 52 patients (27 carteolol and 25 nadolol) were analyzed for drug efficacy. The most commonly chosen dosage levels were 20 mg of carteolol and 80 mg of nadolol. There were no statistically significant differences between the carteolol and nadolol groups in changes in exercise tolerance as reflected by time to onset of angina, end-point of exercise, and onset of 1 mm ST segment change on ECG. Both drugs significantly suppressed tachycardia and double product during treadmill exercise. The nadolol-treated group demonstrated a significantly greater reduction in resting heart rate (18.7 bpm) as compared with the carteolol-treated group (3.1 bpm). Carteolol possesses intrinsic sympathomimetic activity (ISA), which may account for the fact that carteolol effectively reduces exercise-induced tachycardia while producing relatively little effect on resting heart rate. The frequency of anginal attacks and the use of sublingual nitroglycerin were reduced to a similar extent in both treatment groups. The most commonly reported side effect in both treatment groups was asthenia.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of nadolol on the spontaneous and exercise-provoked heart rate of patients with chronic atrial fibrillation receiving stable dosages of digoxin

Nadolol, a long-acting beta-adrenergic-blocking agent, was evaluated in 20 patients with chronic atrial fibrillation by means of a randomized, double-blind, crossover study. Patients were required either to demonstrate resting heart rates in excess of 80 bpm or to show a rate of 120 bpm or an increment of greater than 50 bpm during mild treadmill exercise provocation (3 minutes, 1.75 mph, 10% grade). With placebo the group averaged a heart rate of 92 +/- 19 bpm, determined by 24 hours of ambulatory ECG recordings; this rate was significantly reduced to 73 +/- 16 bpm (p less than 0.001) with nadolol (mean dosage, 87 +/- 43 mg/day). During standardized exercise testing, heart rates increased to 153 +/- 26 bpm with placebo and to 111 +/- 24 bpm with nadolol (p less than 0.001), representing 65% and 52% increments, respectively. Digoxin blood levels averaged 0.8 +/- 0.5 ng/ml with placebo and were similar with nadolol (0.9 +/- 0.4; p = NS). Total exercise time on a modified Bruce treadmill protocol was 466 +/- 143 seconds with placebo and was significantly decreased by nadolol (380 +/- 143; p less than 0.01). During initial dose titration with nadolol, one patient was dropped from study for intolerable fatigue and one for worsened claudication. No patients were dropped from the double-blind treatment periods, although two patients receiving nadolol and one patient receiving placebo complained of moderate fatigue. We conclude that nadolol is a safe and effective agent for the control of spontaneous and exercise-provoked heart rates in patients with chronic atrial fibrillation who were already receiving digoxin treatment.

Nadolol compared to propranolol for treating chronic stable angina pectoris

In order to determine the relative efficacy and dose equivalency of propranolol four times a day and nadolol once daily for the treatment of stable angina pectoris, ten patients were studied in a double blind randomized placebo controlled crossover study. Total daily doses of propranolol and nadolol were determined by titrating until an equivalent degree of reduction in the heart rate response to exercise was achieved. At these doses, the treadmill exercise time to 0.1 mV of electrocardiographic ST-segment depression was increased from 248 +/- 75 seconds on placebo to 405 +/- 56 seconds on propranolol (p less than 0.05) and 471 +/- 46 seconds on nadolol (p less than 0.01). Also, the mean frequency of angina decreased from eight attacks per week on placebo to three on propranolol and nadolol (both p less than 0.05). In six of the ten patients, the effective total daily dose of propranolol and nadolol was identical, and the dose ratio for all ten patients was 1.17:1, propranolol to nadolol. However, individual dose titration is recommended when switching from propranolol four times a day to nadolol once daily because of the dosage variability noted in 40 percent of the patients.

Bepridil for chronic stable angina pectoris: results of a prospective multicenter, placebo-controlled, dose-ranging study in 77 patients

Bepridil, a new calcium-channel blocking agent with an extended plasma elimination half-life of greater than 50 hours, was compared to placebo in 77 patients with confirmed coronary artery disease and chronic stable angina pectoris. The effects of bepridil were compared with those of placebo on angina frequency, nitroglycerin tablet use, the resting ECG and hemodynamics at rest and maximal exercise using a study design comprising 5 sequential 2-week single-blind treatment phases. After 2 weeks of placebo (phase 1), bepridil was given for 3 phases (2, 3 and 4) at total daily dosages of 200, 300 and 400 mg, respectively; the study was completed after a final reintroduction of placebo (phase 5). Within each phase once- and twice-daily regimens of bepridil were randomly compared. Bepridil (300 mg/day) reduced anginal frequency 68%, from 8.5 +/- 1.1 (standard error of the mean) to 2.7 +/- 0.7 attacks/week and nitroglycerin tablet use 76% (p less than 0.001). Bepridil improved exercise duration 26%, from 6.9 +/- 0.4 to 8.7 +/- 0.5 minutes (p less than 0.001) and exercise work 52%, from 2.7 +/- 0.3 to 4.1 +/- 0.4 kpm X 10(-3) (p less than 0.001) on a standardized treadmill protocol. Resting and peak exercise heart rate and blood pressure were unaffected by bepridil. The antianginal effects were similar with either once- or twice-daily treatment schedules. Minor side effects of nausea, epigastric discomfort and tremor were infrequent and there were no major side effects. The results of this large but preliminary, single-blind and short-term study suggest that bepridil is an effective and well tolerated antianginal agent when administered once daily.