TRIP

FDA staff unsure about new use for Amgen's Xgeva

Reuters Health News, 2012

Mon, Feb 6 2012 Thu, Feb 2 2012 Wed, Feb 1 2012 Tue, Jan 31 2012 Fri, Jan 27 2012
WASHINGTON (Reuters) - Reviewers from Food and Drug Administration said they were not sure whether Amgen Inc's Xgeva bone drug should be also approved as a treatment to delay the spread of cancer to the bone.
The FDA reviewers' concerns, raised in documents released on Monday, appeared to dim any serious hopes that an advisory panel of outside experts would recommend approval of an expanded use of Xgeva, viewed by analysts as a drug whose sales could reach $1 billion a year.
Xgeva, an injectable drug known chemically as denosumab, is approved to prevent fractures caused by cancer that has spread to the bone, but not to prevent or delay the spread.
It is seen as one of the most important growth drivers for Amgen, the world's largest biotechnology company.
"Based on the many concerns and questions raised by the FDA, we do not expect the advisory committee to endorse approval of denosumab for this indication," Geoffrey Porges, an analyst for Sanford Bernstein, said in a research note.
The advisory panel will meet on Wednesday to decide whether to recommend approval of the drug for the wider use.
Xgeva delayed the spread of cancer to the bone by a little longer than four months in a clinical trial of 1,432 men with prostate cancer who had stopped responding to hormone therapy.
Amgen said the drug would be targeted at about 50,000 men in the United States at that stage of the disease.
The FDA reviewers said it was unclear whether that length of time without cancer spreading was "an adequate measure of clinical benefit," especially as the drug did not help men live longer or delay the growth of prostate cancer.
SERIOUS SIDE EFFECT The reviewers were also concerned that about one in 20 men treated with the drug developed osteonecrosis of the jaw, or death of jawbone tissue, and said it was uncertain whether the rate could be even higher if patients take the drug for a longer period.