Amgen's osteoporosis drug set for filing after phase 3 results

Amgen and UCB's romosozumab has shown strong top-line phase 3 results in cutting bone fractures in women with osteoporosis.

Romosozumab met both primary endpoints in the study by reducing the incidence of new vertebral fractures over 12 and 24 months in postmenopausal women with the condition.

The drug also met one secondary endpoint of reducing the incidence of clinical fractures (both composite of vertebral and non-vertebral fractures) in post-menopausal women during 12 months post-treatment.

The FRAME study found women receiving romosozumab via subcutaneous injection were shown to have a 73% reduction in the relative risk of vertebral fracture through 12 months compared to women receiving a placebo. These effects continued through to 24 months with the treatment and rose to a statistically significant 75% when combined with denosumab treatment. In addition, a 36% relative risk reduction of clinical fracture was seen up to 12 months with the treatment compared to a placebo.

Professor Dr Iris Loew-Friedrich, Chief Medical Officer and Executive Vice President, UCB, described the results as "encouraging" as the drug was shown to reduce vertebral fractures as early as 12 months. However, she also highlighted the need for a deeper understanding of the results.

Amgen and UCB are targeting Lilly's Forteo (teriparatide) as its main existing market competitor. Lilly's drug requires daily dosing by injection, whereas romosozumab is injected just once a month. Forteo currently earns sales of around $1.35 billion, a market share which the new treatment could steal.

Romosozumab will help Amgen broaden its therapeutic reach, adding to its new cholesterol drug Repatha (evolocumab) and multiple myeloma drug Kyprolis (carfilzomib).

Further analysis of the phase 3 FRAME study continues, with an anticipated potential filing expected later this year.