Recent Developments and Future Directions

Abstract

Ibandronate, a very potent third-generation compound, has been developed and clinically tested during the 1990s. Results of the two randomized, double-blind, three-arm studies (BM 21 0955 i.v. in tumor-induced hypercalcemia: SG 97/91 and SG 107/92) have been published recently and are summarized in the subsection “Bisphosphonates” of the section “Hypercalcemia of Malignancy”. An oral formulation has been investigated in patients with breast cancer and bone metastases (SG 98/91). A dose-dependent inhibition of bone resorption was demonstrated, but occasional gastrointestinal side effects led to the development of a new oral formulation of ibandronate. Ibandronate was also tested as an intravenous bolus injection in tumor-induced osteolysis (SG 122/93). Again, a dose-dependent inhibition of bone resorption as measured by biochemical markers of bone turnover was found. Tolerance was excellent. Finally, a prospective, randomized, double-blind, placebo-controlled, three-arm, phase-III study of ibandronate has been conducted in patients with breast cancer and bone metastases (SG 143/94). No results are available to the public so far.