Amgen, one of the world's leading independent biotechnology companies, and UCB, a global biopharmaceutical company, announced top-line results from the STRUCTURE trial (STudy evaluating effect of RomosozUmab Compared with Teriparatide in postmenopaUsal women with osteoporosis at high risk for fracture pReviously treated with bisphosphonatE therapy). The study (NCT01796301) met the primary endpoint, demonstrating a statistically significant difference in favour of romosozumab in the per cent change of total hip bone mineral density (measured by DXA) through month 12.
STRUCTURE was a phase 3, multi-center, international, randomized, open-label, teriparatide-controlled study that evaluated safety, tolerability and efficacy of romosozumab in women with postmenopausal osteoporosis. A total of 436 patients previously treated with bisphosphonate therapy received either subcutaneous romosozumab (210 mg monthly) or subcutaneous teriparatide (20 mcg daily) through to month 12.
The overall subject incidence of adverse events was generally balanced between arms. Adverse events in patients treated with romosozumab were similar to those previously reported and no new safety signals were detected. Adverse events reported in the romosozumab arm in more than five percent of patients were nasopharyngitis, arthralgia, back pain, headache and fall.
Further analysis of the phase 3 STRUCTURE study results are ongoing and will be submitted to a future medical conference and for publication.
Romosozumab is an investigational bone-forming monoclonal antibody and is not approved by any regulatory authority for the treatment of osteoporosis. It is designed to work by inhibiting the protein sclerostin, thereby increasing bone formation and decreasing bone breakdown. Romosozumab is being studied for its potential to reduce the risk of fractures in an extensive global phase 3 programme. This programme evaluating the safety and efficacy of romosozumab includes two large fracture trials comparing romosozumab to either placebo or active comparator in more than 10,000 postmenopausal patients with osteoporosis. First results from the phase 3 study FRAME are expected in H1 2016. Romosozumab is being co-developed by Amgen and UCB.
Osteoporosis affects many women after menopause as their ability to form new bone cannot counter balance the rate at which bone is being removed. This bone loss leads to weakened bones over time, increasing the potential for a break.
About half of all women over age 50 will have an osteoporosis-related fracture in their remaining lifetime. Additionally, patients with a previous hip fracture have a threefold greater risk of a subsequent fracture within two years.
The World Health Organisation has officially declared osteoporosis a public health crisis, while the International Osteoporosis Foundation urges governments worldwide to make osteoporosis a healthcare priority.