Osteoporosis is proving amenable to treatment

On 27 July the US Food and Drug Administration held a public hearing on an application for a licence for the use of recombinant human parathyroid hormone in the treatment of postmenopausal osteoporosis. The application, from Eli Lilly, is for teriparatide (Forsteo), the N-terminal fragment rhPTH(1-34). The hearing's advisory panel voted unanimously in favour of the parathyroid hormone and approval could be expected after resolution of a few technical concerns. The application was partly based on solid evidence that parathyroid hormone, given as a daily injection for several weeks or months in experimental animals, increases bone mass and strength.1 This evidence led to a multicentre randomised controlled trial in women with osteoporosis, which showed that treatment with parathyroid hormone reduced spine fractures by 66% to 90% (according to whether smaller fractures and those causing minor symptoms were counted) and other fractures by 50%.2

The first experiments showing an anabolic effect of parathyroid hormone on bone in young rats took place in various North American laboratories …