Federal regulators’ approval of Amgen Inc.’s bone drug denosumab for the treatment of bone complications in cancer patients now opens the door to a large and lucrative oncology market that analysts widely expect to exceed $1 billion in annual sales for the biotech giant. Denosumab, under the brand name Prolia, was first approved by the Food and Drug Administration in June for use by postmenopausal women who face a high risk of bone fractures. Following the FDA’s approval for use by cancer patients earlier this month, the Thousand Oaks-based company will begin distributing denosumab under the different name Xgeva, which could bring the company billions of dollars in revenue, according to analysts. “Approval of Xgeva in the oncology setting could favorably affect Amgen’s financial outlook in the short and longer term,” wrote analyst John Sonnier in a William Blair and Company investment report, which estimated 2011 Prolia/Xgeva sales of $712 million. “We see a significant market opportunity for Xgeva in the oncology setting, as there are about 380,000 patients in the United States diagnosed with bone metastases with only the minority on current therapy.” In the third quarter Prolia had sales of $10 million. Combined with Xgeva, analysts project denosumab could bring in $2.4 billion in sales by 2015. Xgeva, which uses a dose of denosumab that is approximately 12 times higher than Prolia, was approved for prevention of skeletal-related events in patients with bone metastases from solid tumors Nov. 18. Amgen is currently testing the drug for preventing cancer from spreading to the bone. Results of that clinical trial are expected before the end of 2010 and a positive outcome could further increase the market potential for the Xgeva brand and accelerate its launch. Amgen has a lot riding on Xgeva and denosumab. The company is counting on the drug to revive sales as revenues for the company have mostly remained flat over the last four years. Amgen, which in 2009 had revenues of $14.6 billion, has struggled with slowing sales of its top seller drugs Epogen and Aranesp in recent years after facing safety complications and increased competition. The company derives 33 percent of its total revenue from its anemia drugs –Epogen and Aranesp. Competitor Amgen’s key products are slated to lose patent protection in the next few years, which is another reason Xgeva is important to the company’s future. But growing Xgeva into a blockbuster drug will mean that Amgen will have to grab market share from key competitor Zometa, sold by Novartis AG., which had U.S. sales of $718 million last year. According to Amgen, clinical studies have shown Xgeva is more effective than Zometa in breast cancer and prostate cancer patients, while the two drugs were shown to be similar in other solid tumors. Dr. Roy Baynes, vice president of Global Development at Amgen, said there are other key differentiators between Xgeva and its main competitor. For one, Zometa can be toxic to the kidneys, he said, and requires measuring a patient’s kidney function before administering a dose, as stated on its label. “With Xgeva there is no direct kidney toxicity and you do not adjust the dose for kidney function,” he said. Another key differentiator is that Zometa has to be given intravenously, which requires scheduling and some planning, he said. “By contrast Xgeva is given as a subcutaneous injection given once a month, it’s a simple shot, and the simplicity of delivery we believe will bring tremendous value for patients and caregivers.” More expensive Although Xgeva will cost about $1,650 per dose, almost twice the price of Zometa, which costs about $844 per dose given every three to four weeks, Amgen believes Xgeva will have the upper hand and will quickly become the mainstay of cancer care when it comes to bone complications. “Today’s approval of XGEVA illustrates what is possible when scientific innovation, commitment and investment come together to advance medicine,” said Kevin Sharer, chairman and chief executive officer of Amgen, in a statement. “A diagnosis of bone metastases is a major event for patients living with cancer, and the consequences can be devastating.” To ensure patient access to the drug, Amgen is starting a co-pay assistance program intended to help eligible patients meet their deductible, co-insurance, and/or co-payment requirements under the medical benefit for Xgeva. Under this program, eligible patients will incur no out of pocket costs for their initial Xgeva injection and pay a maximum of $25 for subsequent injections.