Three years' experience with the biological agent denosumab used to treat women with postmenopausal osteoporosis: efficacy, safety and treatment adherence

Objective: to evaluate the efficacy and tolerability of denosumab and adherence to treatment with this drug in women with postmenopausal osteoporosis (OP) during a three-year prospective study under the conditions of routine clinical practice Subjects and methods. The investigation included 48 women (mean age 65.2+9.1 years) with postmenopausal OP; the patients were recruited in April 2013 to March 2014. All the patients underwent densitometry of three regions and determination of the levels of calcium, creatinine, and alkaline phosphatase over time and vitamin D at inclusion into the study. Adverse events were recorded every 6 months. Results and discussion. 92% of the patients received denosumab during a year, 81.25 and 66.7% - for two and three years, respectively. In 5 (10.4%) women with a low fracture risk according to the FRAX®, during the treatment their bone mineral density (BMD) reached the level seen with osteopenia or normal levels; and the patients were switched to use only calcium and vitamin D. After 3 years, there were significant BMD increases in the lumbar spine by 8.54%, in the femoral neck by 4.77%, in the entire proximal femur by 5.65%, and in the distal forearm by 1.99%. The prior use of other antiosteoporotic drugs did not reduce the efficiency of denosumab treatment. There was no clinical fractures during a 3-year follow-up. Compliance with dosage regimen was observed in 90.6% of the women who completed the three-year follow-up. Age, marital status, education level, time taken to reach a clinic, parental hip fractures, a history of fractures, duration of OP, and previous treatment did not influence treatment adherence. Conclusion. The three-year prospective follow-up in real clinical practice has shown that denosumab is an effective and safe agent to treat patients with postmenopausal OP.