Often referred to as the ‘silent epidemic’, osteoporosis is a global problem that is increasing in significance as the population of the world both increases and ages. The World Health Organization has recently identified osteoporosis as a priority health issue, along with other major non-communicable diseases.

Despite the availability of osteoporosis treatments for more than ten years, patients with osteoporosis still experience a substantial number of fractures [1]. Of an estimated nine million new osteoporotic fractures globally in 2000, 1.7 million were at the forearm, 1.6 million were at the hip, and 1.4 million were clinical (symptomatic) fractures of the vertebrae in the backbone [2].

Denosumab is a fully human monoclonal antibody that targets RANK ligand and is being investigated for its potential to prevent and treat a broad range of bone disease conditions including osteoporosis, bone metastases and their consequences, cancer treatment-induced bone loss due to hormone ablative therapy, multiple myeloma, and bone erosions in rheumatoid arthritis. Denosumab is the first late-stage investigational therapy that specifically inhibits RANK ligand, an essential mediator of the cells that break down bone. The denosumab development programme has more than 19000 patients in trials across indications worldwide, making it the largest ever initiated by Amgen.

Amgen will commercialize the drug for postmenopausal osteoporosis and oncology in the United States and Canada and for all oncology indications in Europe and specified markets. GlaxoSmithKline will register and commercialize denosumab for all indications in countries where Amgen does not currently have a commercial presence, including China, Brazil, India and South Korea. Financial terms of the partnership include an initial payment, near-term commercial milestones to Amgen totalling $120 million and ongoing royalties. In Europe, Amgen and GlaxoSmithKline will share profits after accounting for expenses associated with the partnership. In emerging markets, GlaxoSmithKline will be responsible for all commercialization expenses and purchase denosumab from Amgen to meet demand. The companies' combined commercialization activities will expand access to denosumab, once approved, to patients worldwide who are afflicted by osteoporosis and other bone loss conditions.

In July 2007, Amgen granted Daiichi Sankyo exclusive rights to develop and commercialize denosumab in Japan in postmenopausal osteoporosis and oncology with the potential for additional indications. This arrangement remains in place.