Once-Yearly Leuprolide for Advanced Prostate Cancer Available

The Bayer Corporation announced recently that Viadur(leuprolide acetate implant), a once-yearly implant for the palliative treatmentof advanced prostate cancer, is now available in the United States. The newproduct offers patients 12 months of continuous testosterone suppression—analternative to the 1-, 3-, or 4-month injections currently in use.

The Viadur implant is inserted under the skin of the patient’supper arm during an office procedure. It provides steady serum concentrations ofleuprolide throughout the 12-month dosing period. Leuprolide is the primary drugused for testosterone-suppression therapy of advanced prostate cancer.

"Viadur was effective in suppressing testosterone below thecastrate threshold. It also was generally well tolerated in open-label clinicaltrials, in which 90% of patients chose to continue Viadur therapy for a second12-month period," said James Gottesman, md, of the University of WashingtonMedical School.

Clinical Studies

In two open-label, multicenter studies, 131 patients withadvanced prostate cancer were treated with the 12-month leuprolide implant andevaluated for up to 2 years. Following the initial surgical insertion of theimplant, mean serum testosterone concentrations decreased to therapeuticallydesirable levels by week 4 in 99% of the patients in the studies. Once serumtestosterone suppression was achieved, testosterone levels remained suppressedfor the duration of the 12-month treatment phase.

The most common side effects associated with the use ofonce-yearly leuprolide were hot flashes (67.9%), asthenia (7.6%), gynecomastia(6.9%), depression (5.3%), and sweating (5.3%). The most common local sideeffects were bruising (34.6%) and burning (5.6%).