by Loren Bonner
, DOTmed News Online Editor | May 16, 2013
The U.S. Food and Drug Administration approved a novel radiopharmaceutical on Wednesday aimed at treating men with advanced prostate cancer.
"It's novel in the clinic because it's the only therapeutic radiopharmaceutical we have that is an alpha emitter," Frederic H. Fahey, DSc, president of the Society of Nuclear Medicine and Molecular Imaging (SNMMI), told DOTmed News.
Other radioactive therapeutic agents used routinely are beta emitting. According to Fahey, the advantage of it being an alpha particle-emitting radioactive therapeutic agent is that it can be administered at a higher dose to the site where it's being delivered. In other words, cancer is more precisely targeted while healthy surrounding tissue is spared.
"That probably attributes to why it seems to be more effective than other treatments that have been used in these prostate cancer patients and also why it seems to have fewer side effects," said Fahey.
The drug, radium Ra 223 dichloride, commercially known as Xofigo, was approved under the agency's priority review program three months ahead of schedule. The expedited review was given to the drug because it appears to provide safe and effective therapy when no satisfactory alternative therapy exists, according to the FDA.
The drug is targeted at men with metastatic castration-resistant prostate cancer that has spread to just the bones. It's also suggested for men who have received medical or surgical therapy to lower testosterone.
FDA approval for the drug was based on the results of a single clinical trial that evaluated 809 men with symptomatic castration-resistant prostate cancer that spread to bones but not to other organs. Results showed that it prolonged the patients' lives by a median of 14 months compared to a median of 11.2 months for men receiving the placebo. According to the FDA, an exploratory updated analysis conducted later in the trial confirmed Xofigo's ability to extend overall survival.
Radium Ra 223 dichloride is the second prostate cancer drug approved by the FDA in the past year that demonstrates an ability to extend the survival of men with metastatic prostate cancer, according to Dr. Richard Pazdur, director of the Office of Hematology and Oncology Products in the FDA's Center for Drug Evaluation and Research.
Fahey said SNMMI encourages the FDA to continue reviewing, and when appropriate, approve other nuclear medicine and molecular imaging radiopharmaceuticals that can play a role in improving patient care. Back to HCB News