Adverse Events Leading to Discontinuation
In placebo-controlled trials of 6 months or less, 8% of Campral-treated patients discontinued treatment due to an adverse event, as compared to 6% of patients treated with placebo. In studies longer than 6 months, the discontinuation rate due to adverse events was 7% in both the placebo-treated and the Campral-treated patients. Only diarrhea was associated with the discontinuation of more than 1% of patients (2% of Campral-treated vs. 0.7% of placebo-treated patients). Other events, including nausea, depression, and anxiety, while accounting for discontinuation in less than 1% of patients, were nevertheless more commonly cited in association with discontinuation in Campral-treated patients than in placebo-treated patients.
Common Adverse Events Reported in Controlled Trials
Common adverse events were collected spontaneously in some controlled studies and using a checklist in other studies. The overall profile of adverse events was similar using either method. shows those events that occurred in any Campral treatment group at a rate of 3% or greater and greater than the placebo group in controlled clinical trials with spontaneously reported adverse events. The reported frequencies of adverse events represent the proportion of individuals who experienced, at least once, a treatment-emergent adverse event of the type listed, without regard to the causal relationship of the events to the drug.
Table 1
Table 1. Events Occurring at a Rate of at Least 3% and Greater than Placebo in any Campral Treatment Group in Controlled Clinical Trials with Spontaneously Reported Adverse Events.| Body System/Preferred Term | Number of Patients (%) with Events |
|---|
Campral 1332 mg/day
| Campral 1998 mg/day
1 | Campral Pooled
2 | Placebo |
|---|
|
|
|
| Number of patients in Treatment Group | 397 | 1539 | 2019 | 1706 |
| Number (%) of patients with an AE | 248 (62%) | 910 (59%) | 1231 (61%) | 955 (56%) |
| Body as a Whole | 121 (30%) | 513 (33%) | 685 (34%) | 517 (30%) |
| Accidental Injury*† | 17 ( 4%) | 44 ( 3%) | 70 ( 3%) | 52 ( 3%) |
| Asthenia | 29 ( 7%) | 79 ( 5%) | 114 ( 6%) | 93 ( 5%) |
| Pain | 6 ( 2%) | 56 ( 4%) | 65 ( 3%) | 55 ( 3%) |
| Digestive System | 85 (21%) | 440 (29%) | 574 (28%) | 344 (20%) |
| Anorexia | 20 ( 5%) | 35 ( 2%) | 57 ( 3%) | 44 ( 3%) |
| Diarrhea | 39 (10%) | 257 (17%) | 329 (16%) | 166 (10%) |
| Flatulence | 4 ( 1%) | 55 ( 4%) | 63 ( 3%) | 28 ( 2%) |
| Nausea | 11 ( 3%) | 69 ( 4%) | 87 ( 4%) | 58 ( 3%) |
| Nervous System | 150 (38%) | 417 (27%) | 598 (30%) | 500 (29%) |
| Anxiety††** | 32 ( 8%) | 80 ( 5%) | 118 ( 6%) | 98 ( 6%) |
| Depression | 33 ( 8%) | 63 ( 4%) | 102 ( 5%) | 87 ( 5%) |
| Dizziness | 15 ( 4%) | 49 ( 3%) | 67 ( 3%) | 44 ( 3%) |
| Dry mouth | 13 ( 3%) | 23 ( 1%) | 36 ( 2%) | 28 ( 2%) |
| Insomnia | 34 ( 9%) | 94 ( 6%) | 137 ( 7%) | 121 ( 7%) |
| Paresthesia | 11 ( 3%) | 29 ( 2%) | 40 ( 2%) | 34 ( 2%) |
| Skin and Appendages | 26 ( 7%) | 150 (10%) | 187 ( 9%) | 169 (10%) |
| Pruritus | 12 ( 3%) | 68 ( 4%) | 82 ( 4%) | 58 ( 3%) |
| Sweating | 11 ( 3%) | 27 ( 2%) | 40 ( 2%) | 39 ( 2%) |
Concomitant Therapies
In clinical trials, the safety profile in subjects treated with Campral concomitantly with anxiolytics, hypnotics and sedatives (including benzodiazepines), or non-opioid analgesics was similar to that of subjects taking placebo with these concomitant medications. Patients taking Campral concomitantly with antidepressants more commonly reported both weight gain and weight loss, compared with patients taking either medication alone.
Other Events Observed During the Premarketing Evaluation of Campral
Following is a list of terms that reflect treatment-emergent adverse events reported by patients treated with Campral in 20 clinical trials (4461 patients treated with Campral, 3526 of whom received the maximum recommended dose of 1998 mg/day for up to one year in duration). This listing does not include those events already listed above; events for which a drug cause was considered remote; event terms which were so general as to be uninformative; and events reported only once which were not likely to be acutely life-threatening.
Events are further categorized by body system and listed in order of decreasing frequency according to the following definitions: frequent adverse events are those occurring in at least 1/100 patients (only those not already listed in the summary of adverse events in controlled trials appear in this listing); infrequent adverse events are those occurring in 1/100 to 1/1000 patients; rare events are those occurring in fewer than 1/1000 patients.
: headache, abdominal pain, back pain, infection, flu syndrome, chest pain, chills, suicide attempt; : fever, intentional overdose, malaise, allergic reaction, abscess, neck pain, hernia, intentional injury; : ascites, face edema, photosensitivity reaction, abdomen enlarged, sudden death.
Body as a Whole –FrequentInfrequentRare
: palpitation, syncope; : hypotension, tachycardia, hemorrhage, angina pectoris, migraine, varicose vein, myocardial infarct, phlebitis, postural hypotension; : heart failure, mesenteric arterial occlusion, cardiomyopathy, deep thrombophlebitis, shock.
Cardiovascular System –FrequentInfrequentRare
: vomiting, dyspepsia, constipation, increased appetite; : liver function tests abnormal, gastroenteritis, gastritis, dysphagia, eructation, gastrointestinal hemorrhage, pancreatitis, rectal hemorrhage, liver cirrhosis, esophagitis, hematemesis, nausea and vomiting, hepatitis; melena, stomach ulcer, cholecystitis, colitis, duodenal ulcer, mouth ulceration, carcinoma of liver.
Digestive System –FrequentInfrequentRare:
goiter, hypothyroidism.
Endocrine System –Rare:
: anemia, ecchymosis, eosinophilia, lymphocytosis, thrombocytopenia; leukopenia, lymphadenopathy, monocytosis.
Hemic and Lymphatic System –InfrequentRare:
– peripheral edema, weight gain; : weight loss, hyperglycemia, SGOT increased, SGPT increased, gout, thirst, hyperuricemia, diabetes mellitus, avitaminosis, bilirubinemia; alkaline phosphatase increased, creatinine increased, hyponatremia, lactic dehydrogenase increased.
Metabolic and Nutritional Disorders –FrequentInfrequentRare:
– myalgia, arthralgia; : leg cramps; rheumatoid arthritis, myopathy.
Musculoskeletal System –FrequentInfrequentRare:
–somnolence, libido decreased, amnesia, thinking abnormal, tremor, vasodilatation, hypertension; : convulsion, confusion, libido increased, vertigo, withdrawal syndrome, apathy, suicidal ideation, neuralgia, hostility, agitation, neurosis, abnormal dreams, hallucinations, hypesthesia; : alcohol craving, psychosis, hyperkinesia, twitching, depersonalization, increased salivation, paranoid reaction, torticollis, encephalopathy, manic reaction.
Nervous System –FrequentInfrequentRare
: rhinitis, cough increased, dyspnea, pharyngitis, bronchitis; : asthma, epistaxis, pneumonia; laryngismus, pulmonary embolus.
Respiratory System –FrequentInfrequentRare:
: rash; : acne, eczema, alopecia, maculopapular rash, dry skin, urticaria, exfoliative dermatitis, vesiculobullous rash; psoriasis.
Skin and Appendages –FrequentInfrequentRare:
: abnormal vision, taste perversion; : tinnitus, amblyopia, deafness; ophthalmitis, diplopia, photophobia.
Special Senses –FrequentInfrequentRare:
: impotence; – metrorrhagia, urinary frequency, urinary tract infection, sexual function abnormal, urinary incontinence, vaginitis; kidney calculus, abnormal ejaculation, hematuria, menorrhagia, nocturia, polyuria, urinary urgency.
Urogenital System –FrequentInfrequentRare:
Serious Adverse Events Observed During the Non-US Postmarketing Evaluation of Campral (acamprosate calcium)
The serious adverse event of acute kidney failure has been reported to be temporally associated with Campral treatment in at least 3 patients and is not described elsewhere in the labeling.
Pregnancy Category C
Absorption
The absolute bioavailability of Campral after oral administration is about 11%. Steady-state plasma concentrations of acamprosate are reached within 5 days of dosing. Steady-state peak plasma concentrations after Campral doses of 2 x 333 mg tablets three times daily average 350 ng/mL and occur at 3-8 hours post-dose. Coadministration of Campral with food decreases bioavailability as measured by C and AUC, by approximately 42% and 23%, respectively. The food effect on absorption is not clinically significant and no adjustment of dose is necessary.
max
Distribution
The volume of distribution for acamprosate following intravenous administration is estimated to be 72-109 liters (approximately 1 L/kg). Plasma protein binding of acamprosate is negligible.
Metabolism
Acamprosate does not undergo metabolism.
Elimination
After oral dosing of 2 x 333 mg of Campral, the terminal half-life ranges from approximately 20-33 hours. Following oral administration of Campral, the major route of excretion is via the kidneys as acamprosate.
Special Populations
Campral does not exhibit any significant pharmacokinetic differences between male and female subjects.
Gender:
The pharmacokinetics of Campral have not been evaluated in a geriatric population. However, since renal function diminishes in elderly patients and acamprosate is excreted unchanged in urine, acamprosate plasma concentrations are likely to be higher in the elderly population compared to younger adults.
Age:
The pharmacokinetics of Campral have not been evaluated in a pediatric population.
Pediatrics:
: Peak plasma concentrations after administration of a single dose of 2 x 333 mg Campral tablets to patients with moderate or severe renal impairment were about 2-fold and 4-fold higher, respectively, compared to healthy subjects. Similarly, elimination half-life was about 1.8-fold and 2.6-fold longer, respectively, compared to healthy subjects. There is a linear relationship between creatinine clearance values and total apparent plasma clearance, renal clearance and plasma half-life of acamprosate. A dose of 1 x 333 mg Campral, three times daily, is recommended in patients with moderate renal impairment (creatinine clearance of 30-50 mL/min, [ ].
Renal Impairmentsee Use in Specific Populations ( )
8.6
Campral is contraindicated in patients with severe renal impairment (creatinine clearance of ≤30 mL/min) [ and ].
see Dosage and Administration ( ), Contraindications ( ), Warnings and Precautions ( ),
2.14.25.1Use in Specific Populations ( )
8.6
: Acamprosate is not metabolized by the liver and the pharmacokinetics of Campral are not altered in patients with mild to moderate hepatic impairment (groups A and B of the Child-Pugh classification). No adjustment of dosage is recommended in such patients.
Hepatic Impairment
: A cross-study comparison of Campral at doses of 2 x 333 mg three times daily indicated similar pharmacokinetics between alcohol-dependent subjects and healthy subjects.
Alcohol-dependent subjects
Drug-Drug Interactions
Acamprosate had no inducing potential on the cytochrome CYP1A2 and 3A4 systems, and inhibition studies suggest that acamprosate does not inhibit metabolism mediated by cytochrome CYP1A2, 2C9, 2C19, 2D6, 2E1, or 3A4. The pharmacokinetics of Campral were unaffected when co-administered with alcohol, disulfiram or diazepam. Similarly, the pharmacokinetics of ethanol, diazepam and nordiazepam, imipramine and desipramine, naltrexone and 6-beta naltrexol were unaffected following co-administration with Campral. However, co-administration of Campral with naltrexone led to a 33% increase in the C and a 25% increase in the AUC of acamprosate. No adjustment of dosage is recommended in such patients.
in vitroin vivomax
Renal Impairment
A lower dose is recommended for patients with moderate renal impairment. Campral is contraindicated in patients with severe renal impairment (creatine clearance of ≤30 mL/min) [ ].
see Dosage and Administration ( ), Contraindications ( ), Warnings and Precautions ( ) and Use in Specific Populations ( )
2.14.25.18.6
Suicidality and Depression
Families and caregivers of patients being treated with Campral should be alerted to the need to monitor patients for the emergence of symptoms of depression or suicidality, and to report such symptoms to the patient's health care provider [ ].
see Warnings and Precautions ( )
5.2
Alcohol Withdrawal
Use of Campral does not eliminate or diminish withdrawal symptoms [ ].
see Warnings and Precautions ( )
5.3
Pregnancy and Breast Feeding
- Advise patients to notify their physician if they become pregnant or intend to become pregnant during therapy.
- Advise patients to notify their physician if they are breast-feeding.
Relapse to Drinking
- Advise patients to continue Campral therapy as directed, even in the event of relapse and remind them to discuss any renewed drinking with their physicians.
- Advise patients that Campral has been shown to help maintain abstinence only when used as a part of a treatment program that includes counseling and support.
Manufactured by: Merck Santé s.a.s. Subsidiary of Merck KGaA, Darmstadt, Germany 37, rue Saint-Romain 69008 LYON FRANCE
Manufactured for: Forest Pharmaceuticals, Inc. Subsidiary of Forest Laboratories, Inc. St. Louis, MO 63045