Bone loss after allogeneic haematopoietic stem cell transplantation: a pilot study on the use of zoledronic Acid.

Purpose. Bone loss is a common phenomenon following allogeneic haematopoietic stem cell transplantation (allo-HSCT). The study aimed on tolerance and efficacy of zoledronic acid (ZA) in patients after allo-HSCT. Methods. 40 patients' with osteoporosis or osteopenia were recruited on this phase II study. ZA was given at a dose of 4 mg IV every 3 months for 2 years (yrs). BMD was determined by dual-energy X-ray absorptiometry (LS lumbar spine, FH femur hip). Patients were evaluated for deoxypyridinoline (Dpd) and calcium excretion by longitudinal measurements. Results. 36 patients who had received at least 3 doses of ZA were evaluable. 26 patients had at least two BMD measurements since baseline (BMD group). Among these patients, BMD increased from 0.97 ± 0.15 to 1.10 ± 0.18 g/cm² (LS baseline-2 yrs, Δ+11.6 ± 6.0%, P < 0.001) and from 0.82 ± 0.10 to 0.91 ± 0.10 g/cm(²) (FH baseline-2 yrs, Δ+7.5 ± 7.0%, P < 0.001). Factors associated with an increase in BMD were younger age, female donor sex, and immunosuppression with CSA/MTX. Conclusion. ZA was generally well tolerated; it increases BMD and reduces Dpd excretion significantly in patients with bone loss after allo-HSCT.