Dendreon reports positive results from prostatic hyperplasia trial

In a preclinical study, benign prostatic hyperplasia (BPH) was induced through subcutaneous injection of testosterone propionate. One week prior to initiation of testosterone, either D-3263 or finasteride, a current treatment for BPH, was administered daily for four weeks. Following treatment, blood was sampled, prostates were collected and weighed, and cross sections were stained with Trp-p8 antibody.

Results showed that the BPH-induced prostates expressed significantly higher levels of Trp-p8 compared to the normal prostates. In comparing untreated BPH-induced prostates to those treated with D-3263, treatment with D-3263 resulted in a 39% reduction in prostate weight compared to control (p=0.004). In addition, treatment with D-3263 resulted in a 98% reduction (2221.2 pg/ml versus 43.1 pg/ml) in plasma dihydrotestosterone (DHT) levels (p=0.004) suggesting D-3263 is affecting androgen metabolism, which is a known stimulant for BPH and prostate cancer.

These effects were seen in a dose-dependent manner, achieving efficacy comparable to finasteride. Histopathological examination post treatment with D-3263 indicated that reduction of prostate size and weight was due to a return to normalcy. Changes in Trp-p8 expression and plasma DHT levels correlated with both efficacy and dose.

David Urdal, chief scientific officer of Dendreon, said: “We look forward to filing an investigational new drug application later this year to initiate a study examining D-3263 in advanced cancer, including prostate cancer.”