Source: Haematologica  |  Posted 6 years ago

By Jill Stein

PARIS, FRANCE -- October 31, 1005 -- The bisphosphonate ibandronate, given either intravenously or orally, is effective for palliation of bone pain for up to 2 years in women with metastatic breast cancer, according to summary data from phase 3 trials reported at the 13[^]th[] Annual Meeting of the European Cancer Conference (ECCO).

Debu Tripathy, MD, professor of medicine, University of Texas Southwestern Medical Center, Dallas, Texas, summarized data from 3 96-week, randomized, double-blind, placebo-controlled trials of ibandronate in breast cancer patients with bone metastases.

"Bone is the most common site of metastasis in breast cancer, affecting 65% to 75% of patients," Dr. Tripathy pointed out. "Painful metastatic bone disease has a negative impact on patient wellbeing by eroding quality of life, reducing mobility, and contributing to morbidity."

In a 312-patient trial of IV ibandronate, a 6-mg dose was compared with placebo infused over 1 to 2 hours every 3 to 4 weeks. In 2 trials of oral ibandronate that enrolled 564 women, a 50-mg daily dose was compared with placebo.

Bone pain was evaluated using a 5-point scale, where a score of 0 referred to no pain and 4 referred to pain that was intolerable. Opioid analgesic use was assessed with a 7-point scale, where a score of 0 referred to no need for analgesics and 6 meant that at least 100 mg morphine or an equivalent per day were needed.

Results showed that both formulations of ibandronate significantly decreased pain scores below baseline throughout the 2 years of treatment. The mean change at endpoint was -0.28 for the 6-mg dose versus +0.21 for placebo (P < .001). For the 50-mg dose, the change was -0.10 compared with +0.20 for placebo (P = .001).

Events requiring radiotherapy were significantly reduced with ibandronate versus placebo (IV ibandronate 16.5% reduction, P = .011; oral ibandronate 25.5%, P < .001).

Opioid analgesic use was lower with ibandronate than placebo, reaching statistical significance for the oral formulation (P = .019).

Dr. Tripathy said that oral ibandronate offers a convenient alternative to IV bisphosphonate therapy and allows self-administration.

More recent reports suggest that a loading-dose of IV ibandronate (ibandronate 6 mg on 3 consecutive days with a total dose of 18 mg) achieved a rapid (within 3 days) and significant analgesic effect in patients with metastatic breast cancer.

Dr. Tripathy said the finding that both formulations of ibandronate significantly decrease bone pain even in the presence of a concomitant decrease in the use of analgesics and radiation therapy implies that ibandronate is responsible for pain relief rather than the analgesics and radiotherapy.

He added that 2 phase 3 trials (Bon-I-Pain and Bon-O-Pain) are currently recruiting patients and are designed to assess the efficacy of loading-dose IV ibandronate followed by IV or oral ibandronate for metastatic breast cancer.

The study was sponsored by Hoffman-La Roche Inc., Nutley, New Jersey.

[Presentation title: Effect of Intravenous and Oral Ibandronate on the Need for Analgesic Interventions for Metastatic Bone Pain. Abstract 404]