WILMINGTON, Del--Zeneca Pharmaceutical's Casodex (bicaluta-mide), a new nonsteroidal antiandrogen, has received FDA approval for the hormonal treatment of advanced prostate cancer in combination with a luteinizing-hormone-releasing hormone analog (LHRH-A). The agent acts by binding to cytosol androgen receptors.
Casodex, available as 50-mg tablets, has the convenience of one tablet, once daily dosing, the company said.
In a large multicenter, double-blind, controlled clinical trial, 813 patients with previously untreated advanced prostate cancer were randomized to receive Casodex, 50 mg once daily, or flutamide(Drug information on flutamide) (Eulexin), 250 mg three times daily, each in combination with an LHRH-A. At a median follow-up of 95 weeks, time to treatment failure with use of Casodex/LHRH-A therapy was similar to that of flutamide/LHRH-A therapy.
At the same timepoint, 130 patients (32%) treated with the Casodex combination and 145 (35%) treated with the flutamide combination had died. Assessment of quality of life questionnaires indicated no significant differences between the two treatment groups.
In this study, the most frequent adverse experience with Casodex was hot flashes (49%). Diarrhea was the adverse event most frequently leading to treatment withdrawal: 6% of patients treated with flutamide/LHRH-A and 0.5% of patients treated with Casodex/LHRH-A. Of those on Casodex, 10% reported diarrhea, compared with 24% on flutamide.
Other adverse effects of Casodex included pain (general) (27%), back pain (15%), asthenia (15%), pelvic pain (13%), infection (10%), constipation (17%), and nausea (11%).
"I believe it's important to give prostate cancer patients a choice of treatments," said Gerald W. Chodak, MD, codirector, Urologic Oncology, University of Chicago Hospitals and Clinics, and an investigator in the Casodex clinical trials. "The availability of Casodex means that patients choosing combination drug therapy can lower the chances that they will have diarrhea as a side effect of the antiandrogen," he said.