Solo epothilone yields 21% response rate in androgen-independent prostate cancer

First-line treatment with a novel agent known as sagopilone yields a high response rate and substantial decline in PSA in men with androgen-independent prostate cancer, according to findings presented at the European Society for Medical Oncology 33rd Congress.

Stockholm, Sweden-First-line treatment with a novel agent known as sagopilone yields a high response rate and substantial decline in PSA in men with androgen-independent prostate cancer, according to findings presented at the European Society for Medical Oncology 33rd Congress.

Interim results from the U.S. multicenter phase II study were presented by Tomasz M. Beer, MD, associate professor of medicine at Oregon Health & Science University, Portland.

Patients with AIPC can benefit from treatment with taxanes, which act by stabilizing microtubules, leading to mitotic arrest and apoptosis. The current standard of care is treatment with docetaxel (Taxotere) combined with prednisone (Deltasone, Meticorten, Orasone, et al), which has shown a survival benefit in androgen-independent disease.

"Sagolipone proves to have important activity against advanced prostate cancer, but full assessment of the benefit this drug can provide to patients will require a randomized study," Dr. Beer told Urology Times.

The current phase II study involved 53 patients not previously treated for AIPC. Median baseline PSA was 108.0 ng/mL. Two-thirds of patients had undergone surgery and more than half had been treated with radiotherapy. Bone metastases were present in 74% of patients, and visceral metastases in 25%.

All patients received sagopilone, 16 mg/m² intravenously every 21 days, and oral prednisone, 5 mg twice daily continuously for up to six cycles. For patients with perceived benefit, treatment could be extended.

A confirmed ≥50% reduction in PSA at any time during treatment was observed in 17 of 46 (37%) evaluable patients, which satisfied the primary endpoint of the trial. Within 3 months of treatment, 25 (56%) of the 46 patients experienced a 30% reduction in PSA, Dr. Beer reported. The overall response rate in patients with measurable disease was 21%, which included one complete response and six partial responses. Stable disease was observed in another 18 patients (53%). Most patients found the treatment highly tolerable, Dr. Beer said.

Two members of the study team have affiliations with Bayer Schering Pharma.