A 28.2 μg twice-weekly regimen of teriparatide has a similar efficacy compared with a 56.5 μg once-weekly regimen, but with improved safety outcomes, among patients with osteoporosis at high risk for fracture,1 according to study results presented at the American Society of Bone and Mineral Research 2019 Annual Meeting, held September 20 to 23, 2019, in Orlando, Florida.
Previous studies have showed that 56.5 μg teriparatide taken once weekly can significantly reduce the risk for vertebral fractures (by 80%) in patients with osteoporosis.2 However, adverse drug reactions including nausea or vomiting have contributed to low treatment continuation rates.
This multicenter, double-blind, double-dummy study conducted in Japan included patients with primary osteoporosis aged ≥65 years who were at high risk for fracture (n=553). Patients were randomly assigned to either teriparatide 28.2 μg twice weekly (n=277) or 56.5 μg once weekly (n=276). The primary endpoint was the percentage change in lumbar spine (L2-L4) bone mineral density at 48 weeks.
At final follow-up, the percentage change in lumbar spine bone mineral density was 7.3% in the 28.2 μg group compared with 5.9% in the 56.5 μg group, with a difference in percentage change of 1.3% (95% CI, 0.400%-2.283%). These results demonstrated noninferiority in the 28.2 μg group using the prespecified noninferiority margin of -1.6%.
Patients in the 28.2 μg group had significantly fewer adverse drug reactions compared with the 56.5 μg group (39.7% vs. 56.2%; P <.01). In addition, compared with the 56.5 μg group, the 28.2 μg group had a lower incidence of major adverse drug reactions and a lower rate of discontinuation by patients because of adverse drug reactions.
Disclosure: Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.
1. Sugimoto T, Shiraki M, Hagino H, Yoshimura T, Nakamura T. Study of twice-weekly injections of teriparatide by comparing efficacy with once-weekly injections in osteoporosis patients: the TWICE study. Presented at: American Society of Bone and Mineral Research Annual Meeting 2019; September 20-23, 2019; Orlando, FL. Poster 778.
2. Nakamura T, Sugimoto T, Nakano T, et al. Randomized Teriparatide [human parathyroid hormone (PTH) 1-34] Once-Weekly Efficacy Research (TOWER) trial for examining the reduction in new vertebral fractures in subjects with primary osteoporosis and high fracture risk. J Clin Endocrinol Metab. 2012;97:3097-3106.