Objective: To evaluate the efficacy of Ibandronate sodium 3 mg IV injection in routine clinical practice for treatment of postmenopausal osteoporosis.

Materials and Methods: With approval of the Ethical Committee, 21 bisphosphonate naïve patients were recruited to receive Ibandronate sodium 3 mg IV injection every three months for 12 months. After the last injection, the patients were followed up at months 12 and 18. The serum level of bone resorption marker, the carboxy-terminal collagen crosslinks (sCTX) were measured at baseline, one week, and every three months before the next injection. Bone mass density (BMD) were evaluated at baseline and month 12. Adverse events were evaluated. Serum creatinine were evaluated at baseline, end of treatment, and end of follow up.

Results: Median sCTX reduction was 86.9% within one week after injection from 614.5 pg/mL to 84.0 pg/mL. Median sCTX declined to 329.0, 289.0, 305.0, 285.0 pg/mL at month 3, 6, 9, and 12, respectively. Six months after the last treatment, median sCTX was elevated to 433.0 pg/mL or 75.1% of the baseline. Two non-responders, or 9.5%, with low sCTX at the baseline were found. At month 12, lumbar spine and hip BMD were significantly increased by 4.29% (p=0.003), and 2.20% (p=0.05), respectively. For safety perspective, there was no change in median estimated glomerular filtration rate (eGFR) level from baseline to month 12. Mild to moderate adverse effects had occurred in 33.3% of the patients, myalgia and flu-like symptoms were the most common findings.

Conclusion: Ibandronate injection is effective for postmenopausal osteoporosis treatment. It rapidly reduced sCTX to lower than the average level of premenopausal reference range, which could relate to fracture risk reduction. It has significantly increased lumbar spine and hip BMD. Safety profile was promising with a quick off-response and an unchanged renal function. Ibandronate injection has better compliance and advantage for patients having difficulty in complying with oral treatment.

Keywords: IV bisphosphonate; Postmenopausal osteoporosis; Bone turnover marker; Quick off-response

DOI: 10.35755/jmedassocthai.2022.10.13671

Received 25 April 2022 | Revised 21 July 2022 | Accepted 3 August 2022