New study reveals how to improve chemotherapy use in Prostate Cancer

Prostate cancer is the second leading cause of cancer for men in the United States. Only one class of chemotherapy called taxanes is effective against the disease. A study published online in Clinical Cancer Research, researchers have found that a newer member of the taxane family called cabazitaxel, an FDA approved drug, has properties that could make it more effective for some patients -- a hypothesis currently being tested in clinical trials. Researchers also found a genomic marker that could help physicians identify which patients might benefit most from cabazitaxel.
"It was surprising to find that cabazitaxel functions differently than docetaxel in killing cancer cells, even though they're both taxanes," says senior author Karen Knudsen, Ph.D., Interim Director of the Sidney Kimmel Cancer Center and a professor of cancer biology at the Sidney Kimmel Medical College at Thomas Jefferson University. "It shows that we may not be taking full advantage of this next generation taxane in the clinic."
For years, docetaxel has been the only effective chemotherapy for men whose cancer was no longer responding to hormone treatments. The next generation drug in the taxane family, cabazitaxel, was approved in 2010, but only for patients whose cancer no longer responded to hormone therapy or docetaxel treatment.
Drs. Kelly and Knudsen are testing their hypothesis in a phase II clinical trial (ABICABAZI NCT02218606), currently recruiting patients. The study is funded by Sanofi and conducted as a collaboration between Sidney Kimmel Cancer Center and Memorial-Sloan Kettering Cancer Center. Patients with metastatic prostate cancer who have not yet been treated with chemotherapy will be given either the second-line hormone therapy abiraterone, or abiraterone in combination with cabazitaxel. In addition, researchers will scan the tumors for their RB gene expression to test whether low levels of RB correlate with strong responses to cabazitaxel.
"These results from our laboratory research give us a strong reason to believe that this drug could be more useful to some men earlier in their course of treatment," says Dr. Knudsen. "The ABICABAZI trial puts these ideas to the test in humans, and if we are correct, has the capacity for the first time to tell us what patients might most benefit from chemotherapy."