Once-Daily Therapy for Hepatitis B
The FDA has approved telbivudine (Tyzeka), a new drug indicated for the treatment of chronic hepatitis B virus (HBV). It is a once-daily therapy for adult chronic hepatitis B patients with evidence of viral replication, and either evidence of persistent elevations in serum aminotransferases or histologically active liver disease.
Approval of the new medication was based in large part on data from a Phase III clinical trial that compared telbivudine with lamivudine in 1,367 patients. In hepatitis e antigen (HBeAg)-positive patients, therapeutic response was 75% among patents treated with telbivudine, compared with 67% for those treated with lamivudine. For HBeAg-negative patients after 1 year, the respective response rates were 75% and 77%. Patients who achieved undetectable HBV DNA levels at 24 weeks were more likely to undergo "e" antigen seroconversion, achieve sustained undetectable HBV DNA, alanine aminotransferase normalization, and minimize resistance at 1 year.
In clinical trials, telbivudine was generally well tolerated. The most commonly reported adverse events were upper respiratory infections, fatigue/malaise, abdominal pain, sore throat, and headache.
Treatment Approved for Restless Legs Syndrome
Pramipexole dihydrochloride (Mirapex) tablets have been approved for the treatment of moderate-to-severe primary restless legs syndrome (RLS). The medication is a product of Boehringer Ingelheim Pharmaceuticals. The drug is also approved to treat the signs and symptoms of idiopathic Parkinson's disease.
For the RLS indication, pramipexole is approved in varying doses and should be taken daily 2 to 3 hours before bedtime.
Approval of the new indication was based on safety and efficacy data from four randomized, double-blind, placebo-controlled trials involving approximately 1,000 patients. Patients taking pramipexole experienced statistically and clinically significant improvements in short- and long-term efficacy versus placebo.
Pramipexole may cause patients to fall asleep without warning, even during normal daily activities such as driving. Hallucinations may occur when taking the medication, and sometimes patients may feel dizzy, sweaty, or nauseated upon standing up.
OC Gets New Indication for PMDD
The FDA has approved Berlex/Schering's oral contraceptive (OC) Yaz (3 mg drospirenone/20 mcg ethinyl estradiol, in a 24-day active pill regimen), to treat premenstrual dysphoric disorder (PMDD) for women who choose to use OCs for contraception. Yaz is the first and only OC that is also clinically effective in treating the emotional and physical symptoms of PMDD.
The approval was based on a clinical trial of 450 women 18 to 40 years of age with symptoms of PMDD. Yaz was significantly superior to placebo in improving interpersonal relationships, work productivity, and enjoyment of hobbies and social activities. Forty-eight percent of patients taking Yaz experienced a reduction in symptom severity by at least one-half, as measured by the Daily Record of Severity of Problems.
FDA Warning: Compounding Anesthetic Creams
The FDA has warned five firms to stop compounding and distributing standardized versions of topical anesthetic creams, which are marketed for general distribution rather than responding to the unique medical needs of individual patients. The creams are often used to lessen pain in procedures such as laser hair removal, tattoos, and skin treatments.
Like all compounded drugs, compounded topical anesthetic creams are not reviewed by the FDA for safety and effectiveness and are not FDA-approved.
The agency is concerned about the serious public health risks associated with compounded topical anesthetic creams. Exposure to high concentrations of local anesthetics, can cause serious reactions such as seizures and irregular heartbeats.