[Bisphosphonate treatment of osteoporosis and other skeletal diseases]

Abstract

Background: Bisphosphonates are antiresorptive drugs widely used to treat osteoporosis. They are also used to treat hereditary skeletal diseases with systemic or local defects, and as a supplement in treatment of cancer. This paper provides an overview of pharmacokinetics, mode of action, and clinical effects.

Material and methods: Literature was retrieved through a non-systematic search in Pubmed/Medline.

Results: Bisphosphonates are derivates of pyrophosphate which bind to hydroxyapatite with high affinity. Aminobisphosphonates inhibit an enzyme in the mevalonate pathway, thereby inducing apoptosis and inhibiting osteoclast activity. A reduced incidence of vertebral and hip fractures has been shown for alendronate, risedronate and zoledronate, while ibandronate has been shown to only reduce vertebral fracture. Reduced mortality was observed in a study where patients with recent hip fracture were treated with zoledronic acid. Intravenous bisphosphonates improve compliance and are relatively simple to use. Bisphosphonates reduce the risk for skeletal complications and bone pain in breast cancer, myelomatosis and prostate cancer. They are also effective in the treatment of Paget's disease and bone marrow edema. Gastrointestinal adverse effects are relatively frequent with peroral bisphosphonates, while acute phase reactions with influenza-like symptoms are common with intravenous bisphosphonates.

Interpretation: Aminobisphoshonates are effective in the treatment of osteoporosis and in other bone diseases, and as an adjuvance in the treatment of cancer.