Amgen and GlaxoSmithKline (GSK) have announced a collaboration to share commercialisation of Amgen’s monoclonal antibody denosumab for postmenopausal osteoporosis (PMO) in Europe, Australia, New Zealand and Mexico.

The structure of the collaboration allows Amgen the option of an expanded role in commercialisation once the treatment is approved in countries in Europe and certain emerging markets in the future.

Denosumab is a fully human monoclonal antibody that that specifically inhibits RANK Ligand, an essential mediator of the cells that break down bone.

The treatment is being investigated for its potential to prevent and treat a broad range of bone disease conditions including osteoporosis, bone metastases, cancer treatment-induced bone loss, and multiple myeloma and bone erosions in rheumatoid arthritis.

Amgen will commercialise the drug for PMO and oncology in the US and Canada and for all oncology indications in Europe and specified markets.

GSK will then register and commercialise denosumab for all indications in countries where Amgen does not have a commercial presence, including China, Brazil, India and South Korea.

GSK will make an initial payment and near-term commercial milestones to Amgen totalling $120m. In Europe, Amgen and GSK will share profits after accounting for expenses associated with the partnership. In emerging markets, GSK will be responsible for all commercialisation expenses and purchase denosumab from Amgen to meet demand.

Amgen CEO Kevin Sharer said that the collaboration with GSK will help bring denosumab to patients in Europe and other parts of the world more effectively.

“Amgen and GSK together are uniquely positioned to help medical providers and patients understand the clinical promise and economic value of denosumab,” Sharer said.

In July 2007, Amgen granted Daiichi Sankyo exclusive rights to develop and commercialise denosumab in Japan.