Phase III data on FP 001 (leuprolide mesylate injectable suspension) in prostate cancer- Foresee Pharmaceuticals

Foresee Pharmaceuticals has announced the top-line result of FP 001 (leuprolide mesylate injectable suspension) 50mg phase III clinical trial, an open-label, single-arm study in subjects with Advanced Prostate Carcinoma. The primary efficacy end point was achieved in 97.0% of subjects. The primary efficacy end point is the percentage of subjects with suppression of serum testosterone (below 50 ng/dl) by day 28 and from day 28 to day 336 in the intent-to-treat (ITT) population.

The targeted efficacy was that the lower limit of the 2-sided 95% confidence interval (CI) for suppression is to be more than 90%. In this study, 137 subjects were enrolled and received a minimum of one dose of the study drug (ITT population), and 124 subjects completed the study without major protocol violations that would affect the primary efficacy endpoint (per-protocol population (PP)). The 95% CI from Kaplan-Meier estimates was (92.2%, 98.9%), and the 95% repeated-confidence interval was (92.5%, 99.4%). By day 28, mean testosterone concentration was suppressed below castrate levels to 17.6 ng/dL, and the suppression rate was 98.5% (135 out of 137 subjects achieved medical castration). No mean increase in testosterone was observed after the second injection. Four subjects did not achieve successful suppression of testosterone by the primary efficacy end point analysis, two of which failed to achieve castration level on day 28 and the other two had transient testosterone escapes.

The most common adverse events reported in this study include "hot flushing" (48.9%), followed by "hypertension" (14.6%), "injection site pain" (7.3%), "fatigue" (6.6%), etc., most in mild or moderate intensity. Overall, treatment with LMIS 50 mg injection every 6 months was safe and well tolerated. These safety data are similar to those of marketed LH-RH agonists in the same patient population.