Recombinant human PTH 1-34 (Forteo): an anabolic drug for osteoporosis.

Forteo (teriparatide of rDNA origin), a genetically engineered fragment of parathyroid hormone, is the first of a new class of drugs to treat osteoporosis. The drug's anabolic action increases bone turnover, stimulating osteoblasts to a greater extent than osteoclasts, and reducing both vertebral and nonvertebral fractures. However, a number of issues about its use remain unanswered.