Response to zoledronic acid in patients with active Paget's disease of bone: A retrospective study

Abstract

Background: Traditionally, bisphosphonates are used to treat active Paget's disease of bone (PDB). Intravenous zoledronic acid (ZA) is the most effective treatment option leading to sustained remission. Objective: The primary objective of this study was to analyze the effect of intravenous ZA in patients with active PDB in a tertiary care center of India. Materials and Methods: Retrospective data of 13 patients with active PDB who received a single dose of 4 mg intravenous ZA at our institute from January 2011 to June 2017 were reviewed. Response to therapy was monitored clinically, biochemically by serum alkaline phosphatase (ALP), and scintigraphically by 99m-Technetium methylene diphosphonate bone scan. Results: All of our patients reported relief of bone pain. The mean duration of follow-up in our study was 35.2 ± 16.8 months. Serum ALP levels reduced significantly from 1190.9 ± 666.1 IU/L ( n = 13) at baseline to 200.5 ± 68.4 IU/L ( n = 13) at 6 months ( P < 0.001). ALP level at 1 year was 174 ± 33.6 IU/L ( n = 12), which remained stable till 36 months at 176.5 ± 50 IU/L ( n = 8). This indicates that remission achieved by 6 months post ZA is sustained for at least 3 years. Scintigraphic ratio reduced from 9.6 [interquartile range (IQR) 5.25–18.2] at baseline to 2.7 (IQR 1.20–4.05) at follow-up ( P < 0.001). Similarly, scintigraphic index of involvement reduced from 9.9 (IQR 5.6–28.5) at baseline to 3 (IQR 2–4) at follow-up ( P = 0.018). Conclusion: A 4 mg single dose of intravenous ZA results in clinical, biochemical, and scintigraphic response that is sustained for at least 3 years.

Bone scan findings of Paget's disease of bone in patients with VCP Multisystem Proteinopathy 1 (MSP1)

“…There is currently no de nitive treatment for the neuromuscular and neurological manifestations of MSP1. However, treatment with bisphosphonates such as alendronate and zoledronic acid has been noted to provide relief from bone pain in the majority of patients with PDB [14,33,34]. In our cohort, only one patient (ID 4) reported to be taking bisphosphonates who had ve active PDB regions and an ALP level of 234 IU/L.…”

“…In our cohort, only one patient (ID 4) reported to be taking bisphosphonates who had ve active PDB regions and an ALP level of 234 IU/L. Bone scans in addition to ALP levels can be effective in monitoring bone osteoclast reactivation in patients following treatment [34]. Future studies including bone-speci c alkaline phosphatase (BALP), procollagen type I intact N-terminal propeptide (P1NP), and collagen type 1 C-telopeptide (CTX) may provide data on their usefulness in diagnosing and monitoring of PDB in this at-risk population [13].…”