Endocrine Abstracts

Anabolic agents hold the promise of rebuilding the skeleton and thus producing a greater fracture reduction that antiresorptive agents. PTH (either 1–34 or 1–84) suggests improvements in mass and structure, and for 1-34rhPTH significant reductions in vertebral and non-vertebral fractures. Whether the fracture benefits are indeed greater than those seen with bisphosphonates is not clear. The limited duration of clinical trials (and treatment in practice) makes it difficult to determine, as does the absence of head to head fracture studies. In clinical practice many patients have been pretreated with bisphosphonates, and there are significant interactions. Daily therapy, for the 18 months recommended, may not be the only method of PTH use, but other regimens have not been examined in fracture studies, and data on surrogate outcomes is limited. It is clear that PTH use must be followed by an anti-resorptive agent to prevent the gains from dissipating. Several unresolved issues remain, however, including whether routes of administration will be effective, the most effective regimens, and use of combination treatment. Unfortunately, these may remain unresolved at least in studies with fracture outcomes