Zoledronate after denosumab discontinuation: Is repeated administrations more effective than single infusion?

BACKGROUND: After Denosumab (Dmab) discontinuation C-terminal telopeptide (CTX) levels increase, bone mineral density (BMD) decreases and multiple vertebral fractures (FX) may occur with relevant impact on women's health. A sequential therapy with bisphosphonates is recommended and the European Calcified Tissue Society (ECTS) proposed repeated zoledronate (ZOL) administrations in patients with persistently high CTX levels, although the efficacy of this schedule is unknown. In this retrospective study we describe BMD changes and FX rate in 52 patients managed according to the ECTS recommendations. METHODS: We measured CTX levels and administered ZOL after one month from Dmab withdrawal (t0). After 6 months (t1), we administered a second ZOL infusion, if CTX levels were ≥280 ng/L. BMD changes and FX rate were assessed on average after 17 months from Dmab withdrawal. RESULTS: 75% of patients repeated ZOL infusion. In this group spine BMD declined significantly (-5.5 ± 5.6%), while it remained stable in the group with CTX levels <280 ng/L (-0.1 ± 5.5%, p = 0.008). All fractured patients (9.6%) had received >5 Dmab injections and two ZOL infusions. The BMD worsening after Dmab withdrawal was associated with CTX t1 (OR 2.9, IQR 1.3-6.6, p = 0.009) and spine BMD gain during Dmab therapy corrected for the number of Dmab injections (OR 3.0, IQR 1.2-7.2, p = 0.014). A CTX level at t1 > 212 ng/L had 100% sensitivity in predicting the BMD loss. CONCLUSIONS: In patients with uncontrolled CTX levels after Dmab withdrawal, two ZOL infusions at 6 months apart do not prevent BMD loss and FX.

Bone Disease in Long-Term Lung Transplant Survivors.

BACKGROUND: During the first two years after lung transplantation (LTx), the incidence of fragility fractures (FX) is estimated to be 15-50% and it is lower in patients with cystic fibrosis (CF) as compared with other end-stage lung diseases (nCF). The aim of our study is to compare the skeletal outcomes, after the first 2 years post-LTx, in long-term survivors with CF and nCF. MATERIALS AND METHODS: We evaluated the FX rate, the changes in bone mineral density (BMD) and trabecular bone score (TBS) in 68 patients (38 CF and 30 nCF) who underwent LTx in our center and with a follow-up after LTx longer than 5 years (7.3 ± 2.0 years). RESULTS: After the second year post-LTx: (i) the FX rate was lower than during the first two years post-LTx (4.4 vs. 20.6%, p = 0.004), with no difference between CF and nCF patients (5.3 vs. 3.3%, p = 0.589); (ii) BMD at lumbar spine, femoral neck and total hip remained stable (-1.6 ± 1.0 vs. -1.4 ± 1.1, p = 0.431, -1.8 ± 0.9 vs. -1.9 ± 0.9, p = 0.683, -1.5 ± 0.9 vs. -1.4 ± 0.9, p = 0.678, respectively) as well as TBS (1.200 ± 0.124 vs. 1.199 ± 0.205, p = 0.166). CONCLUSIONS: After the second year post-LTx, the skeletal complications become less frequent and have similar incidence in patients with CF and nCF.