Positive Ph III data for Praecis' abarelix

Praecis Pharmaceuticals and development partner Amgen have presenteddata at the annual meeting of the American Urological Association in California, USA, from two Phase III clinical trials which assessed the ability of abarelix, a new class of prostate cancer drug that avoids stimulating the secretion of testosterone, to suppress serum prostate antigen levels and testosterone levels compared with standard hormonal therapy. The studies also evaluated, at the start of therapy, the frequency of hormonal surge, an initial increase in testosterone and other hormonal levels which may, according to urologist Norm Zinner at Western Clinical Research, "stimulate tumor cell growth, elevate PSA levels and potentially worsen the symptoms of cancer during the first weeks of treatment."

Results of the study showed that patients with early- and late-stage prostate cancer treated with abarelix experienced a 50% reduction from baseline serum PSA after two weeks and a 75% reduction after four weeks of treatment, compared to a 15% and 61% reduction with comparator, TAP Pharmaceuticals' Lupron (leuprolide acetate), after two and four weeks, respectively. After 85 days, both patient groups had achieved greater than a 90% reduction in serum PSA levels.

72% of patients treated with abarelix achieved the target testosterone level of 50ng/dL after eight days, compared with none of the patients treated with Lupron, and none of the abarelix-treated patients experienced a surge of testosterone compared with 82% of the Lupron group.