Recombinant hormones in osteoporosis

Abstract

Introduction: For the last 10 years, bone anabolic therapy with the recombinant human parathyroid hormone (rhPTH) analogue, teriparatide (rhPTH[1 – 34]), or full-length rhPTH(1 – 84) has been an option in the treatment of osteoporosis. Both drugs are given as a daily subcutaneous injection. In the USA, only teriparatide is marketed.

Areas covered: Mechanisms of action by which rhPTH induces bone anabolic effects includes changes in bone remodeling, geometry and mineral density. Data from randomized controlled trials on anti-fracture efficacy are reviewed as well as results from a number of recent studies on administration less than once-a-day or intermittent-/cyclic-therapy. Treatment effects are compared with those of anti-resorptive agents.

Expert opinion: In terms of anti-fracture efficacy, treatment with rhPTH is not superior to treatment with potent anti-resorptive agents. However, while the process by which osteoporosis emerges is arrested in response to anti-resorptives, rhPTH acts as a bone anabolic with reversal of the process. Although this mechanism of action seems favorable, the use of rhPTH is limited by a much higher cost than that of anti-resorptive agents. As long as a superior anti-fracture efficacy has not been proven, rhPTH should be confined to patients with severe spinal osteoporosis, including patients in whom treatment with an anti-resorptive has failed.

Keywords::

• bone mineral density
• fracture
• osteoporosis
• parathyroid hormone
• postmenopausal
• teriparatide

Notes

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