Bisphosphonates Relieve Skeletal Pain in Prostate Cancer

ANAHEIM, California—In hormone-refractory prostate cancer patients, bisphosphonates can relieve painful skeletal metastases, according to a study presented at the American Urological Association annual meeting (abstract 691).

Achim Elert, MD, of Phillips University, Marburg, Germany, reported the results of an open-label nonrandomized study of 105 patients with painful osseous metastases who received clodronate (n = 85) or ibandronate (n = 20). The mean survival of the patients was 12 weeks (range, 6 to 22 weeks).

Clodronate was started with an intravenous phase for 8 days at a dose of 300 mg/d followed by an oral maintenance phase at 1,600 mg/d. Ibandronate was given in an intravenous dose of 6 mg monthly. Pain reduction was documented by the use of a 10-point visual analog scale, and consumption of analgesics was documented in a diary.

Palliative responses were seen in 75% of patients receiving clodronate (64 of 85) and in 90% of patients receiving ibandronate (18 of 20). This was demonstrated by a significant reduction in pain scores, from 7.9 to 2.5 in the clodronate group and from 7.3 to 2.1 in the ibandronate group (P < .001).

A number of patients were completely pain free, including 19 of 64 responding clodronate-treated patients (29.7%) and 10 of 18 ibandronate responders (55.5%). Furthermore, 45 patients in the clodronate group and 8 in the ibandronate group had significantly decreased consumption of daily analgesics. Maximum pain reduction was achieved in 12 days with clodronate and 6.5 days with ibandronate, Dr. Elert said.

In both groups, improvement in bone pain was paralleled by an improvement in Karnofsky index, from 45% to 70% at the end of the treatment period, mainly due to improved mobility. No patient suffered a pathologic fracture during treatment.

Clodronate produced more gastrointestinal side effects: 17.7% vs none with ibandronate.