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Clinical Trials Experience
Carvedilol has been evaluated for safety in patients with heart failure (mild, moderate, and severe), in patients with left ventricular dysfunction following myocardial infarction, and in hypertensive patients. The observed adverse event profile was consistent with the pharmacology of the drug and the health status of the patients in the clinical trials. Adverse events reported for each of these patient populations reflecting the use of either COREG CR or immediate-release carvedilol are provided below. Excluded are adverse events considered too general to be informative, and those not reasonably associated with the use of the drug because they were associated with the condition being treated or are very common in the treated population. Rates of adverse events were generally similar across demographic subsets (men and women, elderly and non-elderly, blacks and non-blacks). COREG CR has been evaluated for safety in a 4-week (2 weeks of immediate-release carvedilol and 2 weeks of COREG CR) clinical study (n = 187) which included 157 patients with stable mild, moderate, or severe chronic heart failure and 30 patients with left ventricular dysfunction following acute myocardial infarction. The profile of adverse events observed with COREG CR in this small, short-term study was generally similar to that observed with immediate-release carvedilol. Differences in safety would not be expected based on the similarity in plasma levels for COREG CR and immediate-release carvedilol.
The following information describes the safety experience in heart failure with immediate-release carvedilol.
Carvedilol has been evaluated for safety in heart failure in more than 4,500 patients worldwide of whom more than 2,100 participated in placebo-controlled clinical trials. Approximately 60% of the total treated population in placebo-controlled clinical trials received carvedilol for at least 6 months and 30% received carvedilol for at least 12 months. In the COMET trial, 1,511 patients with mild-to-moderate heart failure were treated with carvedilol for up to 5.9 years (mean 4.8 years). Both in US clinical trials in mild-to-moderate heart failure that compared carvedilol in daily doses up to 100 mg (n = 765) to placebo (n = 437), and in a multinational clinical trial in severe heart failure (COPERNICUS) that compared carvedilol in daily doses up to 50 mg (n = 1,156) with placebo (n = 1,133), discontinuation rates for adverse experiences were similar in carvedilol and placebo patients. In placebo-controlled clinical trials, the only cause of discontinuation > 1%, and occurring more often on carvedilol was dizziness (1.3% on carvedilol, 0.6% on placebo in the COPERNICUS trial).
Table 2 shows adverse events reported in patients with mild-to-moderate heart failure enrolled in US placebo-controlled clinical trials, and with severe heart failure enrolled in the COPERNICUS trial. Shown are adverse events that occurred more frequently in drug-treated patients than placebo-treated patients with an incidence of > 3% in patients treated with carvedilol regardless of causality. Median study medication exposure was 6.3 months for both carvedilol and placebo patients in the trials of mild-to-moderate heart failure, and 10.4 months in the trial of severe heart failure patients. The adverse event profile of carvedilol observed in the long-term COMET study was generally similar to that observed in the US Heart Failure Trials.
Table 2: Adverse Events (%) Occurring More Frequently With
Immediate-Release Carvedilol Than With Placebo in Patients With Mild-to-Moderate
Heart Failure (HF) Enrolled in US Heart Failure Trials or in Patients With Severe
Heart Failure in the COPERNICUS Trial (Incidence > 3% in Patients Treated
With Carvedilol, Regardless of Causality)
|Mild-to-Moderate HF||Severe HF|
(n = 765)
(n = 437)
(n = 1,156)
(n = 1,133)
|Body as a Whole|
|Digoxin level increased||5||4||2||1|
|Central Nervous System|
Cardiac failure and dyspnea were also reported in these studies, but the rates were equal or greater in patients who received placebo.
The following adverse events were reported with a frequency of > 1% but ≤ 3% and more frequently with carvedilol in either the US placebo-controlled trials in patients with mild-to-moderate heart failure, or in patients with severe heart failure in the COPERNICUS trial.
Incidence > 1% to ≤ 3%
Liver and Biliary System: SGPT increased, SGOT increased.
Metabolic and Nutritional: Hyperuricemia, hypoglycemia, hyponatremia, increased alkaline phosphatase, glycosuria, hypervolemia, diabetes mellitus, GGT increased, weight loss, hyperkalemia, creatinine increased.
Musculoskeletal: Muscle cramps.
Reproductive, male: Impotence.
Special Senses: Blurred vision.
Left Ventricular Dysfunction Following Myocardial Infarction
The following information describes the safety experience in left ventricular dysfunction following acute myocardial infarction with immediate-release carvedilol.
Carvedilol has been evaluated for safety in survivors of an acute myocardial infarction with left ventricular dysfunction in the CAPRICORN trial which involved 969 patients who received carvedilol and 980 who received placebo. Approximately 75% of the patients received carvedilol for at least 6 months and 53% received carvedilol for at least 12 months. Patients were treated for an average of 12.9 months and 12.8 months with carvedilol and placebo, respectively.
The most common adverse events reported with carvedilol in the CAPRICORN trial were consistent with the profile of the drug in the US heart failure trials and the COPERNICUS trial. The only additional adverse events reported in CAPRICORN in > 3% of the patients and more commonly on carvedilol were dyspnea, anemia, and lung edema. The following adverse events were reported with a frequency of > 1% but ≤ 3% and more frequently with carvedilol: Flu syndrome, cerebrovascular accident, peripheral vascular disorder, hypotonia, depression, gastrointestinal pain, arthritis, and gout. The overall rates of discontinuations due to adverse events were similar in both groups of patients. In this database, the only cause of discontinuation > 1%, and occurring more often on carvedilol was hypotension (1.5% on carvedilol, 0.2% on placebo).
COREG CR was evaluated for safety in an 8-week double-blind trial in 337 subjects with essential hypertension. The profile of adverse events observed with COREG CR was generally similar to that observed with immediate-release carvedilol. The overall rates of discontinuations due to adverse events were similar between COREG CR and placebo.
Table 3: Adverse Events (%) Occurring More Frequently With COREG CR Than
With Placebo in Patients With Hypertension (Incidence ≥ 1% in Patients
Treated With Carvedilol, Regardless of Causality)
(n = 253)
(n = 84)
The following information describes the safety experience in hypertension with immediate-release carvedilol.
Carvedilol has been evaluated for safety in hypertension in more than 2,193 patients in US clinical trials and in 2,976 patients in international clinical trials. Approximately 36% of the total treated population received carvedilol for at least 6 months. In general, carvedilol was well tolerated at doses up to 50 mg daily. Most adverse events reported during carvedilol therapy were of mild to moderate severity. In US controlled clinical trials directly comparing carvedilol monotherapy in doses up to 50 mg (n = 1,142) to placebo (n = 462), 4.9% of carvedilol patients discontinued for adverse events versus 5.2% of placebo patients. Although there was no overall difference in discontinuation rates, discontinuations were more common in the carvedilol group for postural hypotension (1% versus 0). The overall incidence of adverse events in US placebo-controlled trials was found to increase with increasing dose of carvedilol. For individual adverse events this could only be distinguished for dizziness, which increased in frequency from 2% to 5% as total daily dose increased from 6.25 mg to 50 mg as single or divided doses.
Table 4 shows adverse events in US placebo-controlled clinical trials for hypertension that occurred with an incidence of ≥ 1% regardless of causality, and that were more frequent in drug-treated patients than placebo-treated patients.
Table 4: Adverse Events (% Occurrence) in US Placebo-Controlled
Hypertension Trials With Immediate-Release Carvedilol (Incidence ≥ 1% in Patients
Treated With Carvedilol, Regardless of Causality)*
(n = 1,142)
(n = 462)
|Central Nervous System|
|* Shown are events with rate > 1% rounded to nearest integer.|
Dyspnea and fatigue were also reported in these studies, but the rates were equal or greater in patients who received placebo.
The following adverse events not described above were reported as possibly or probably related to carvedilol in worldwide open or controlled trials with carvedilol in patients with hypertension or heart failure.
Incidence > 0.1% to ≤ 1%
Cardiovascular: Peripheral ischemia, tachycardia.
Central and Peripheral Nervous System: Hypokinesia.
Gastrointestinal: Bilirubinemia, increased hepatic enzymes (0.2% of hypertension patients and 0.4% of heart failure patients were discontinued from therapy because of increases in hepatic enzymes) [see ADVERSE REACTIONS].
Psychiatric: Nervousness, sleep disorder, aggravated depression, impaired concentration, abnormal thinking, paroniria, emotional lability.
Reproductive, male: Decreased libido.
Skin and Appendages: Pruritus, rash erythematous, rash maculopapular, rash psoriaform, photosensitivity reaction.
Special Senses: Tinnitus.
Urinary System: Micturition frequency increased.
Autonomic Nervous System: Dry mouth, sweating increased.
Metabolic and Nutritional: Hypokalemia, hypertriglyceridemia.
Hematologic: Anemia, leukopenia.
The following events were reported in ≤ 0.1% of patients and are potentially important: Complete AV block, bundle branch block, myocardial ischemia, cerebrovascular disorder, convulsions, migraine, neuralgia, paresis, anaphylactoid reaction, alopecia, exfoliative dermatitis, amnesia, GI hemorrhage, bronchospasm, pulmonary edema, decreased hearing, respiratory alkalosis, increased BUN, decreased HDL, pancytopenia, and atypical lymphocytes.
Reversible elevations in serum transaminases (ALT or AST) have been observed during treatment with carvedilol. Rates of transaminase elevations (2- to 3-times the upper limit of normal) observed during controlled clinical trials have generally been similar between patients treated with carvedilol and those treated with placebo. However, transaminase elevations, confirmed by rechallenge, have been observed with carvedilol. In a long-term, placebo controlled trial in severe heart failure, patients treated with carvedilol had lower values for hepatic transaminases than patients treated with placebo, possibly because carvedilol-induced improvements in cardiac function led to less hepatic congestion and/or improved hepatic blood flow.
Carvedilol therapy has not been associated with clinically significant changes in serum potassium, total triglycerides, total cholesterol, HDL cholesterol, uric acid, blood urea nitrogen, or creatinine. No clinically relevant changes were noted in fasting serum glucose in hypertensive patients; fasting serum glucose was not evaluated in the heart failure clinical trials.
The following adverse reactions have been identified during post-approval use of COREG® or COREG CR. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.
Blood and Lymphatic System Disorders: Aplastic anemia.
Renal and Urinary Disorders: Urinary incontinence.
Respiratory, Thoracic and Mediastinal Disorders: Interstitial pneumonitis.
Read the Coreg CR (carvedilol phosphate extended-release) Side Effects Center for a complete guide to possible side effects
CYP2D6 Inhibitors and Poor Metabolizers
Interactions of carvedilol with potent inhibitors of CYP2D6 isoenzyme (such as quinidine, fluoxetine, paroxetine, and propafenone) have not been studied, but these drugs would be expected to increase blood levels of the R(+) enantiomer of carvedilol [see CLINICAL PHARMACOLOGY]. Retrospective analysis of side effects in clinical trials showed that poor 2D6 metabolizers had a higher rate of dizziness during up-titration, presumably resulting from vasodilating effects of the higher concentrations of the α-blocking R(+) enantiomer.
Patients taking both agents with β-blocking properties and a drug that can deplete catecholamines (e.g., reserpine and monoamine oxidase inhibitors) should be observed closely for signs of hypotension and/or severe bradycardia.
Concomitant administration of clonidine with agents with β-blocking properties may potentiate blood-pressure- and heart-rate-lowering effects. When concomitant treatment with agents with β-blocking properties and clonidine is to be terminated, the β-blocking agent should be discontinued first. Clonidine therapy can then be discontinued several days later by gradually decreasing the dosage.
Modest increases in mean trough cyclosporine concentrations were observed following initiation of carvedilol treatment in 21 renal transplant patients suffering from chronic vascular rejection. In about 30% of patients, the dose of cyclosporine had to be reduced in order to maintain cyclosporine concentrations within the therapeutic range, while in the remainder no adjustment was needed. On the average for the group, the dose of cyclosporine was reduced about 20% in these patients. Due to wide interindividual variability in the dose adjustment required, it is recommended that cyclosporine concentrations be monitored closely after initiation of carvedilol therapy and that the dose of cyclosporine be adjusted as appropriate.
Both digitalis glycosides and β-blockers slow atrioventricular conduction and decrease heart rate. Concomitant use can increase the risk of bradycardia. Digoxin concentrations are increased by about 15% when digoxin and carvedilol are administered concomitantly. Therefore, increased monitoring of digoxin is recommended when initiating, adjusting, or discontinuing COREG CR [see CLINICAL PHARMACOLOGY].
Inducers/Inhibitors of Hepatic Metabolism
Rifampin reduced plasma concentrations of carvedilol by about 70% [see CLINICAL PHARMACOLOGY]. Cimetidine increased area under the curve (AUC) by about 30% but caused no change in Cmax [see CLINICAL PHARMACOLOGY].
Amiodarone, and its metabolite desethyl amiodarone, inhibitors of CYP2C9 and P glycoprotein, increased concentrations of the S(-) enantiomer of carvedilol by at least 2-fold [see CLINICAL PHARMACOLOGY]. The concomitant administration of amiodarone or other CYP2C9 inhibitors such as fluconazole with COREG CR may enhance the β-blocking properties of carvedilol resulting in further slowing of the heart rate or cardiac conduction. Patients should be observed for signs of bradycardia or heart block, particularly when one agent is added to pre existing treatment with the other.
Calcium Channel Blockers
Conduction disturbance (rarely with hemodynamic compromise) has been observed when carvedilol is co-administered with diltiazem. As with other agents with β-blocking properties, if COREG CR is to be administered orally with calcium channel blockers of the verapamil or diltiazem type, it is recommended that ECG and blood pressure be monitored.
Insulin or Oral Hypoglycemics
Agents with β-blocking properties may enhance the blood-sugar-reducing effect of insulin and oral hypoglycemics. Therefore, in patients taking insulin or oral hypoglycemics, regular monitoring of blood glucose is recommended [see WARNINGS AND PRECAUTIONS].
Proton Pump Inhibitors
There is no clinically meaningful increase in AUC and Cmax with concomitant administration of carvedilol extended-release capsules with pantoprazole.
If treatment with COREG CR is to be continued perioperatively, particular care should be taken when anesthetic agents which depress myocardial function, such as ether, cyclopropane, and trichloroethylene, are used [see OVERDOSAGE].
Read the Coreg CR Drug Interactions Center for a complete guide to possible interactions
Last reviewed on RxList: 8/19/2011
This monograph has been modified to include the generic and brand name in many instances.
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