Evaluation of a novel osteoporotic drug delivery system in vitro: alendronate-loaded calcium phosphate cement.

As a new drug delivery system, calcium phosphate cement was fabricated with different concentrations of alendronate (2, 5, 10 wt%), which is widely used to treat diseases related to bone loss. This study investigated the properties of the novel composite alendronate-loaded calcium phosphate cement in vitro, and found that the structure and chemical properties of the composites were not different from the calcium phosphate cement. However, the calcium phosphate cement set time was significantly faster compared with other groups (P<.01), and the strength of the calcium phosphate cement was significantly greater than the other groups (P<.01). The alendronate release rate from the composite increased with increase in drug concentration in the cement, and release was sustained over 21 days. The composite showed good biocompatibility in terms of the proliferation of rat mesenchymal stem cells. The alendronate-loaded calcium phosphate cement displayed satisfactory properties in vitro, which may be of benefit locally for osteoporotic bone in vivo.