Intravenous Zoledronic Acid 5 mg on Bone Turnover Markers and Bone Mineral Density in East China Subjects with Newly Diagnosed Osteoporosis: A 24-month Clinical Study.

Objective: This randomized, double-blind, placebo-controlled study assessed the necessity of early intervention, safety and efficacy of intravenous zoledronic acid 5 mg/year in East China women with newly diagnosed osteoporosis at high risk of fracture during a 24-month treatment period.

Methods: Subjects (57 [52-62] years old) were randomized 3:2 to zoledronic acid versus placebo (randomized at baseline, zoledronic acid [175 cases], placebo-zoledronic acid [110 cases]). The bone mineral density of the lumbar spine and total hip was measured every 6 months with the use of dual-energy X-ray absorptiometry. Serum procollagen I N-terminal pro-peptide (PINP) and serum C-telopeptide of type I collagen (CTX) levels were measured every 6 months. The primary end point was the rate of change in the bone mineral density at the posteroanterior spine.

Results: For subjects with measurements at 24 months, zoledronic acid significantly increased bone mineral density (BMD) at the lumbar spine (mean percent change ± SD, zoledronic acid 5.390% ± 0.854% versus placebo-zoledronic acid -1.038% ± 0.599%), the total hip (zoledronic acid 1.900% ± 0.262% versus placebo-zoledronic acid -1.631% ± 0.649%). Serum procollagen I N-terminal pro-peptide (PINP) and CTX decreased rapidly with zoledronic acid 5 mg treatment (P < 0.001 versus placebo at 6 month and 24 months) and changed from baseline in the zoledronic acid 5 mg and placebo-zoledronic acid 5 mg at 6 months by a mean of -66.348% and -75.375%, respectively (P < 0.001), and at 24 months by -49.950% and -52.325%, respectively (P < 0.001). No cases of serious adverse events were observed in two groups. Headache, pyrexia and myalgia occurred more commonly within the first 3 days after infusion with zoledronic acid 5 mg than with placebo (13.7% versus 2.1%, P = 0.0018; 28.0% versus 3.2%, P < 0.001; 21.7% versus 4.2%, P < 0.001, respectively).

Conclusions: These data show that early application of zoledronic acid 5 mg/year was well stimulated and tolerated for bone mass in newly diagnosed east china subjects with osteoporosis in a 24-month treatment.