Amgen's Denosumab Shows Significant Efficacy in Reducing Fracture Risk in Women with Postmenopausal Osteoporosis and Men with Prostate Cancer

Strategic Insights -

Amgen's denosumab, a monoclonal antibody that targets the RANK Ligand pathway, has demonstrated significant efficacy in reducing fracture risk in women with postmenopausal osteoporosis and men with prostate cancer undergoing androgen deprivation therapy (ADT). Two pivotal Phase 3 studies, published in The New England Journal of Medicine, investigated the safety and effectiveness of denosumab in more than 7,800 women with postmenopausal osteoporosis and over 1,400 men with non-metastatic prostate cancer. The results show that patients receiving twice-yearly denosumab experienced significant increases in bone mineral density (BMD) and a more than 60% reduction in vertebral fractures in both patient populations.

Key Takeaways:

  • Women receiving denosumab twice-yearly experienced a 68% reduction in the risk of suffering a vertebral (spine) fracture, a 40% reduction in the risk of suffering a hip fracture, and a 20% reduction in the risk of suffering a nonvertebral fracture compared to those receiving placebo.
  • Men receiving denosumab experienced a 62% reduction in the risk of suffering a new vertebral fracture with denosumab compared to placebo at 36 months, with significant reduction observed as early as month-12.
  • Patients treated with denosumab experienced significant increases in BMD, including an 8.8% increase at the lumbar spine and a 6.4% increase at the total hip in women, and a 6.7% increase in BMD at the lumbar spine and significant increases at non-vertebral sites in men.
  • The overall incidence and type of side effects were similar to placebo in both studies, with rates of adverse events (AEs) ranging from 93% to 87% and rates of serious AEs ranging from 25.8% to 35%.
  • There were no reported cases of osteonecrosis of the jaw among patients treated with denosumab.

Statistics:

  • 7,800 women with postmenopausal osteoporosis were enrolled in the FREEDOM study.
  • 1,468 men with non-metastatic prostate cancer were enrolled in the HALT study.
  • 68% reduction in the risk of suffering a vertebral (spine) fracture in women.
  • 40% reduction in the risk of suffering a hip fracture in women.
  • 20% reduction in the risk of suffering a nonvertebral fracture in women.
  • 62% reduction in the risk of suffering a new vertebral fracture in men.
  • 6.7% increase in BMD at the lumbar spine in men.
  • 93% of women and 87% of men experienced adverse events (AEs).
  • 25.8% of women and 35% of men experienced serious AEs.

Sources:

  • (1) The New England Journal of Medicine, FREEDOM Study Results
  • (2) The New England Journal of Medicine, HALT Study Results
  • Amgen press release, March 12, 2009
  • Cancer Weekly, March 2009, Vol. 12, No. 10