A topic in Clinical Evidence summarizes the results of two RCTs. The first RCT (1637 women with prior vertebral fractures) found that teriparatide reduced vertebral fractures compared with placebo after a mean of 21 months (5% with 20 mg/d, 4% with 40 mg/d vs 14% with placebo, RR for 40 mg/d 0.31, 95% CI 0.19 to 0.50, and non-vertebral fractures (6% with both 20 mg/d (p=0.04) and 40 mg/d (p=0.02) vs 10% with placebo. The second RCT (34 women with osteoporosis taking hormone replacement therapy) found that teriparatide reduced vertebral fractures at 3 years (2/17 vs 7/17, p=0.04).