Amgen (NASDAQ: AMGN) and UCB (Euronext Brussels:UCB) today announced results from a Phase 2 trial evaluating romosozumab (AMG 785/CDP7851) in postmenopausal women with low bone mineral density (BMD). Published in the New England Journal of Medicine (NEJM), the trial demonstrated that, compared with placebo, romosozumab treatment for 12 months significantly increased BMD at the lumbar spine, total hip and femoral neck. Significant increases were also observed in the first BMD assessment at three months. Moreover, in exploratory analyses, increases observed at the lumbar spine and hip were significantly greater than those observed with current treatments FOSAMAX® (alendronate sodium) and FORTEO™/FORSTEO® (teriparatide).
"The results of the study demonstrate significantly increased BMD and stimulation of bone formation with romosozumab treatment in women with postmenopausal osteoporosis," said Michael McClung, M.D., director of the Oregon Osteoporosis Center and lead study investigator. "Additionally, romosozumab treatment resulted in greater increases in bone mineral density than those seen with both placebo and the active comparators. These data provide important insight into this medicine being developed for women with postmenopausal osteoporosis at high risk for fractures."
Romosozumab is an investigational medicine in Phase 3 clinical development for the treatment of osteoporosis in postmenopausal women and is not currently approved by any regulatory authority.
In this Phase 2 trial, each of the five romosozumab dose regimens significantly increased BMD compared with pooled placebo groups at the lumbar spine, total hip and femoral neck regions (all p<0.001). The largest increases were observed with the romosozumab 210 mg once-monthly dose, with mean increases compared with baseline of 11.3 percent at the lumbar spine, 4.1 percent at the total hip and 3.7 percent at the femoral neck.
Additionally, in exploratory analyses, BMD gains were significantly greater than active comparators at month 12, with romosozumab treatment achieving a mean increase of 11.3 percent at the lumbar spine compared to increases of 4.1 percent and 7.1 percent at the same region achieved with FOSAMAX and FORTEO, respectively. At the total hip, romosozumab treatment increased BMD 4.1 percent, while observed gains with FOSAMAX were 1.9 percent and with FORTEO were 1.3 percent (all p<0.001).
The comparators to romosozumab were placebo, oral FOSAMAX (70 mg weekly) and subcutaneous FORTEO (20 μg daily), both of which were open-label.
Adverse events were similar across groups, except for mild, generally non-recurring injection site reactions observed more frequently with romosozumab compared to placebo, but with no observed dose-related relationship. Most common adverse events included mild upper respiratory tract infection, pain in the back and joints, and headache. These reactions did not lead to study drug discontinuation or study withdrawal; the safety of romosozumab will be further addressed in subsequent larger studies.
