/publications/issue/2005/2005-02/2005-02-9223

RxPRODUCT NEWS: PROFILE: Campral(acamprosate calcium)

Author: Claudio Faria, PharmD, RPh; Carolyn Soo, PharmD, RPh; and Sam Barbat

Alcohol dependence affects more than 14 million adults in the United States. Excessive drinking may cause many detrimental problems, such as cancer (primarily of the liver, throat, larynx), liver cirrhosis, brain damage, and fetal complications during pregnancy. Four symptoms are used to characterize alcohol dependence: craving, loss of control, physical dependence, and tolerance. The first step in the treatment of alcohol dependence is the individual's acceptance of the condition. After admitting the problem, other treatment steps can begin.1 Campral is an FDA-approved product from Forest Laboratories that helps maintain self-restraint from alcohol in people who are sober at the beginning of treatment.2

Pharmacology

The exact mechanism of action of Campral is unknown. Alcohol dependence is believed to change the regular balance of neuronal excitation and inhibition. In vitro data suggest that Campral has affinity for type A and type B GABA receptors and that the drug lowers neuronal excitability through the central nervous system. Campral is thought to restore the balance of excitation and inhibition when patients stop using alcohol.3

Clinical Trials

Campral was studied in a double-blind, multicenter, placebo-controlled, randomized study. A total of 455 patients between the ages of 18 and 65 years with chronic or episodic alcohol dependence were enrolled in this study. Patients were randomly assigned to either placebo or Campral 1998 mg per day for body weight >60 kg or 1332 mg per day for body weight <60 kg for 360 days. The results showed that Campral was the superior agent in preventing relapse, when compared with placebo. Study investigators also concluded that Campral was not only effective, but also a well-tolerated adjunct therapy helpful in behavioral or psychosocial treatment programs that involve alcohol- dependent patients.4

Another randomized, double-blind, placebo-controlled study was conducted to compare Campral with placebo, naltrexone with placebo, and a combination of naltrexone and Campral with placebo. A total of 160 patients with alcoholism (according to Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition,5 criteria for alcohol dependence) were enrolled in the study. Patients were randomly assigned to placebo, naltrexone 50 mg per day, Campral 1998 mg per day, or naltrexone plus Campral dosed respectively, for 12 weeks. The results showed the naltrexone, Campral, and combination groups to be more effective in preventing relapse, compared with placebo. Furthermore, the study showed that the naltrexone and Campral combination was the most effective regarding time to first drink and time to relapse, and that the combination produced lower relapse rates than Campral alone and placebo but not lower than naltrexone.6

Safety

Overall, Campral is well tolerated. The most common side effects are diarrhea, nausea/vomiting, depression, and anxiety.3 Other less common side effects include insomnia, asthenia, pruritus, dizziness, dry mouth, paresthesias, and diaphoresis. Because Campral can cause dizziness and might impair judgment. Patients should be cautioned about operating machinery when taking the drug. Contraindications include patients with sulfite hypersensitivity and severe renal impairment or renal failure (creatinine clearance [CrCl] <30 mL/min). Patients with moderate renal impairment (CrCl 30-50 mL/min) should initiate Campral therapy at a reduced dose.3 Additional caution should be taken with patients who suffer from suicidal ideations, the elderly, and women who are breast-feeding. Campral is in pregnancy category C and should be avoided during pregnancy.2,3

Outlook

Campral is available in a 333-mg enteric-coated, delayed-release tablet. The recommended dose is 2 tablets 3 times daily.2 Studies have reported that Campral has a safer adverse drug profile than any medication strictly characterized as an alcohol-dependence agent. Furthermore, studies have found that Campral is even more effective in combination with other agents, such as naltrexone, or with behavioral therapies and counseling.2,3 Campral gives health care practitioners another safe and effective adjunctive therapy option for the treatment of alcohol dependence.

Drs. Faria and Soo are both senior research pharmacists with the Investigational Drug Service at Brigham and Women's Hospital, Boston, Mass. Dr. Faria also is a senior human research specialist at Partners HealthCare System. Mr. Barbat is a sixth-year PharmD candidate at the Massachusetts College of Pharmacy and Health Sciences and currently is at the Brigham and Women's Hospital on a clinical clerkship.

For a list of references, send a stamped, self-addressed envelope to: References Department, Attn. A. Stahl, Pharmacy Times, 241 Forsgate Drive, Jamesburg, NJ 08831; or send an e-mail request to: astahl@mwc.com.