Ibandronate vs Radiotherapy for Bone Pain in Prostate Cancer
Ibandronate vs Radiotherapy for Bone Pain in Prostate Cancer
Background: The radiotherapy or ibandronate (RIB) trial was a randomized multicenter nonblind two-arm trial to compare intravenous ibandronate given as a single infusion with single-dose radiotherapy for metastatic bone pain.
Methods: Four hundred seventy prostate cancer patients with metastatic bone pain who were suitable for local radiotherapy were randomly assigned to radiotherapy (single dose, 8 Gy) or intravenous infusion of ibandronate (6mg) in a noninferiority trial. Pain was measured using the Brief Pain Inventory at baseline and four, eight, 12, 26, and 52 weeks. Pain response was assessed using World Health Organization (WHO) criteria and the Effective Analgesic Score (EAS); the maximum allowable difference was ±15%. Patients failing to respond at four weeks were offered retreatment with the alternative treatment. Quality of life (QoL) was assessed at baseline and four and 12 weeks. Because the trial was designed with a 5% one-sided test, we provide 90% confidence intervals (two-sided) for differences in pain response.
Results: Overall, pain response was not statistically different at four or 12 weeks (WHO: −3.7%, 90% confidence interval [CI] = −12.4% to 5.0%; and 6.7%, 90% CI = −2.6 to 16.0%, respectively). Corresponding differences using the EAS were −7.5% and −3.5%. However, a more rapid initial response with radiotherapy was observed. There was no overall difference in toxicity, although each treatment had different side effects. QoL was similar at four and 12 weeks. Overall survival was similar between the two groups but was better among patients having retreatment than those who did not.
Conclusions: A single infusion of ibandronate had outcomes similar to a single dose of radiotherapy for metastatic prostate bone pain. Ibandronate could be considered when radiotherapy is not available.
Bone metastases are a major cause of morbidity in prostate cancer. Treatment ranges from analgesics, androgen deprivation therapy and bisphosphonates to external beam radiotherapy and systemic isotope therapy. For localized bone pain, radiotherapy is the standard and most effective treatment.
There is increasing evidence that bisphosphonates are effective in the treatment of prostate cancer bone metastases. Oral clodronate has been shown to reduce the incidence of skeletal-related events and even prolong survival in metastatic disease. The use of bisphosphonates as an analgesic for bone pain is supported by only limited data relating to their efficacy.
Ibandronate (ibandronic acid) is one of the new generation of bisphosphonate drugs. It is indicated for the prevention of skeletal events in patients with breast cancer bone metastases and for treatment of tumor-induced hypercalcaemia. A single-arm phase II study showed that ibandronate is effective in controlling metastatic bone pain, and in clinical practice the use of bisphosphonates for pain relief has become common.
There has been no previous direct comparison between radiotherapy and bisphosphonates for pain relief from metastatic bone pain. This prospective randomized trial has therefore been undertaken to compare the standard treatment of radiotherapy with a bisphosphonate infusion in painful bone metastases from prostate cancer.
Abstract and Introduction
Abstract
Background: The radiotherapy or ibandronate (RIB) trial was a randomized multicenter nonblind two-arm trial to compare intravenous ibandronate given as a single infusion with single-dose radiotherapy for metastatic bone pain.
Methods: Four hundred seventy prostate cancer patients with metastatic bone pain who were suitable for local radiotherapy were randomly assigned to radiotherapy (single dose, 8 Gy) or intravenous infusion of ibandronate (6mg) in a noninferiority trial. Pain was measured using the Brief Pain Inventory at baseline and four, eight, 12, 26, and 52 weeks. Pain response was assessed using World Health Organization (WHO) criteria and the Effective Analgesic Score (EAS); the maximum allowable difference was ±15%. Patients failing to respond at four weeks were offered retreatment with the alternative treatment. Quality of life (QoL) was assessed at baseline and four and 12 weeks. Because the trial was designed with a 5% one-sided test, we provide 90% confidence intervals (two-sided) for differences in pain response.
Results: Overall, pain response was not statistically different at four or 12 weeks (WHO: −3.7%, 90% confidence interval [CI] = −12.4% to 5.0%; and 6.7%, 90% CI = −2.6 to 16.0%, respectively). Corresponding differences using the EAS were −7.5% and −3.5%. However, a more rapid initial response with radiotherapy was observed. There was no overall difference in toxicity, although each treatment had different side effects. QoL was similar at four and 12 weeks. Overall survival was similar between the two groups but was better among patients having retreatment than those who did not.
Conclusions: A single infusion of ibandronate had outcomes similar to a single dose of radiotherapy for metastatic prostate bone pain. Ibandronate could be considered when radiotherapy is not available.
Introduction
Bone metastases are a major cause of morbidity in prostate cancer. Treatment ranges from analgesics, androgen deprivation therapy and bisphosphonates to external beam radiotherapy and systemic isotope therapy. For localized bone pain, radiotherapy is the standard and most effective treatment.
There is increasing evidence that bisphosphonates are effective in the treatment of prostate cancer bone metastases. Oral clodronate has been shown to reduce the incidence of skeletal-related events and even prolong survival in metastatic disease. The use of bisphosphonates as an analgesic for bone pain is supported by only limited data relating to their efficacy.
Ibandronate (ibandronic acid) is one of the new generation of bisphosphonate drugs. It is indicated for the prevention of skeletal events in patients with breast cancer bone metastases and for treatment of tumor-induced hypercalcaemia. A single-arm phase II study showed that ibandronate is effective in controlling metastatic bone pain, and in clinical practice the use of bisphosphonates for pain relief has become common.
There has been no previous direct comparison between radiotherapy and bisphosphonates for pain relief from metastatic bone pain. This prospective randomized trial has therefore been undertaken to compare the standard treatment of radiotherapy with a bisphosphonate infusion in painful bone metastases from prostate cancer.
Source...