Combination therapy decreases PSA in hormone-refractory prostate Ca

Combination therapy using an investigational small molecule chemopotentiator reduces PSA levels and symptoms in men with hormone-refractory prostate cancer, according to results of a phase II trial. The combination of the chemopotentiator, known as tesmilifene, plus mitoxantrone/prednisone decreased PSA and reduced symptoms similarly to mitoxantrone/prednisone and docetaxel (Taxotere)/estramustine, reported the authors, led by Derek Raghavan, MD, of the Cleveland Clinic.

The study involved 29 patients (mean age, 73 years) with progressive hormone-refractory prostate cancer who received tesmilifene, 5.3 mg/kg intravenously every 3 weeks; mitoxantrone, 12 mg/m2 intravenously every week; and prednisone, 5 mg orally twice daily. All patients had pain at presentation and 97% had bone metastasis. Median PSA was 210.0 ng/mL.

After treatment, 75% had some pain improvement, 66% had decreased analgesic requirements, 59% had a PSA decrease of 50% or greater, and 45% had a PSA decrease of 75% or greater. The 2-year survival was 21%.

"The high proportion of patients experiencing a 50% and 75% PSA decrease, and dramatic amelioration of pain suggests that this novel regimen may be more effective than mitoxantrone-prednisone alone, especially when the characteristics of advanced age and extensive bony metastases are considered," said Dr. Raghavan, whose study appears in the Journal of Urology (2005; 174:1808-13).