(Updates with closing share price in sixth paragraph.)
Feb. 6 (Bloomberg) -- U.S. regulators questioned whether the ability of Amgen Inc.’s Xgeva to delay tumors spreading to bones justifies its approval in patients with advanced prostate cancer. The drug didn’t extend lives in a study.
Food and Drug Administration staff weighed the drug, chemically known as denosumab, in a report today ahead of an advisory panel that will meet Feb. 8 to recommend whether to expand Xgeva’s use in advanced prostate cancer.
Patients who took Xgeva experienced deadly bone metastases 4.2 months later on average than those that took a placebo, Thousand Oaks, California-based Amgen found in a study published in November in The Lancet. Survival didn’t differ between the groups. Approval would add as much as $500 million to sales of a drug that may already bring in $2 billion or more by 2015, said Michael Yee, an analyst at RBC Capital Markets in San Francisco.
“Wall Street expectations are generally pretty low for the commercial opportunity because doctor feedback is mixed on time to delay of bone metastases,” Yee said.
Amgen forecasts Xgeva sales of $3 billion to $4 billion in 2015. The treatment was approved in November 2010 to prevent bone pain and fractures caused by bone metastases. It is also known as Prolia in the treatment of osteoporosis in menopausal women.
Amgen fell less than 1 percent to $69.12 at the close in New York.
Prostate is one of a handful of cancers that most often spread to the bone. Once tumors reach the bone, the cancer is rarely curable, according to the American Cancer Society.
Xgeva would be for men who are not responsive to hormone treatment and whose cancer hasn’t spread to the bone yet have an increased risk based on testing, a population of about 50,000 in the U.S., Sean Harper, Amgen senior vice president of global development and corporate chief medical officer, said in a telephone interview.
Of the 1,432 patients studied, five percent developed osteonecrosis of the jaw, which can cause jaw pain, tooth infection and bone inflammation, according to The Lancet study. The cancer society said bone metastases are one of the most common causes of pain in people with cancer. Some patients experienced as much as a 7.5-month delay in developing bone metastases, Harper said.
FDA staff were also concerned the drug may “shift the pattern of metastases to non-bony areas.”
Prospects For Approval
“I would not be surprised if this doesn’t get approved,” said Bill Tanner, an analyst at Lazard Capital Markets in New York, in a telephone interview. “The only signal that they’ve seen is dubious clinical benefit.”
The panel considering Xgeva Feb. 8 also met Sept. 14 to discuss testing drugs for prostate cancer patients not responsive to hormone treatment whose cancer hasn’t spread to the bones.
Oncologists on the panel considered a two-year bone metastases delay beneficial while one year and six months was considered questionable, Robyn Karnauskas, an analyst with Deutsche Bank AG in New York, wrote in a Feb. 3 note to clients.
Urologists are more flexible so the make-up of the panel this time may influence the outcome, Karnauskas said. The panel announced today consists of nine oncologists and a biostatistician. The FDA does not have to follow the panel’s recommendation.
The agency is scheduled to make a decision by April 26.
--With assistance from Catherine Larkin in Indianapolis. Editors: Andrew Pollack, Adriel Bettelheim
To contact the reporter on this story: Anna Edney in Washington at email@example.com
To contact the editor responsible for this story: Adriel Bettelheim at firstname.lastname@example.org