Global biotechnology giant Amgen has had its hopes for expanding the scope of Xgeva dashed after US regulators turned down the drug for preventing bone metastases in at risk men with prostate cancer.

One of Amgen's key drugs, Xgeva (denosumab) is already on the market to prevent skeletal events in patients with solid tumours that have spread to the bone, as well as for preventing osteoporotic fractures in postmenopausal women (sold as Prolia), and it is widely expected to become a blockbuster in the future.

The company is hoping to gain additional approval for delaying the spread of cancer to the bone in men with castration-resistant prostate cancer, but the US Food and Drug Administration has concluded that, based on the available data, Xgeva's benefits do not outweigh its risks in this setting.

In May 2011 the company presented Phase III data showing that the drug significantly improved metastases-free survival by 4.2 months, equating to a risk reduction of 15%, compared with a placebo.

But in a complete response letter to the firm, the regulator said the effect of the drug on bone metastases-free survival was of insufficient magnitude to outweigh the risks, including osteonecrosis of the jaw, and it has requested data from "an adequate and well-controlled trial(s) demonstrating a favourable benefit-risk profile". 

According to Sean Harper, executive vice president of research and development at Amgen, the firm intends to "work with the FDA to determine any next steps," though it is looking likely that this could involve potentially lengthy and costly extra clinical studies.

Ramps up production

In more positive news and a great boon for the Irish economy, Amgen is investing heavily in the expansion of its manufacturing facility in Dun Laoghaire, Dublin, to ramp up its global production.

The group will sink at least £200 million into expanding its facilities on site, in a move that should create around 100 new jobs, just a year after it snapped up the facility from pharma giant Pfizer.

The expansion programme will include the construction of around 11,700 square metres of building extension, and a major technology process enhancement to upgrade the plant into a cutting edge manufacturing site.

IDA Ireland, the country's inward investment promotion agency, has worked alongside Amgen to help secure the investment.

Welcoming the move, Irish Prime Minister Enda Kenny said his government will "work hard to support an environment where R&D can flourish so that the IDA can continue to attract important investment and jobs like this".

"By providing the right environment and a commitment to support R&D investment, Ireland has positioned itself as a leading location for biotech investments", added IDA Ireland's chief executive Barry O'Leary.