Long-term control of Paget's disease of bone with low-dose, once-weekly, oral bisphosphonate preparations, in a "real world" setting.

PURPOSE: Bisphosphonates are the mainstay of the treatment of Paget's disease of bone (PDB). Clinical practice guidelines recommend treatment with intravenous zoledronic acid or high-dose oral nitrogen bisphosphonates (N-BPs). We present our long-term experience treating PDB patients with lower than recommended oral doses of N-BPs, equivalent to once-weekly doses used for treating osteoporosis. METHODS: PDB patients were seen, between 1990 and 2015 at the endocrine clinic of an academic medical center. Diagnosis was established according to accepted criteria. Patients were initially treated with alendronate 70 mg/week or risedronate 35 mg/week. Whenever the initial dose failed to produce remission, the dosage was increased to twice a week the respective dose. RESULTS: Patients were followed for a mean of 11.9 years (range: 1.7-24.8). Out of 96 treatment courses with N-BPs, 89% were with alendronate and 11% with risedronate. Remission was achieved in 84% of the courses with alendronate 70 mg/week. 90% of those who did not achieve remission subsequently responded to 140 mg/week. Out of the 8 treatment courses with risedronate 35 mg/week, 87% achieved remission, and the 2 patients who did not achieve remission subsequently responded to 70 mg/week. The median duration of remissions following 3-4 months courses of alendronate 70 mg/week or risedronate 35 mg/week was 8.8 months (IQR: 5.5, 14.8). CONCLUSION: In a large proportion of "real world" PDB patients, remission can be achieved with once-weekly, "osteoporosis doses" of alendronate or risedronate.