SAN FRANCISCOIn a phase I study, 7 of 18 patients with measurable advanced breast cancer receiving sunitinib (Sutent) and paclitaxel as first-line therapy had an objective response (38.9%), including two complete responses, researchers reported at the ASCO Breast Cancer Symposium (abstract 163). Responses were seen in 3 of 8 patients with measurable triple-negative (ER, PR, and HER2) disease. Sunitinib is an oral multikinase inhibitor FDA approved for advanced renal cell cancer and progressive GIST.
A phase III study (SUN 1094) of sunitinib/paclitaxel vs bevacizumab (Avastin)/paclitaxel as first-line therapy of advanced breast cancer is currently underway, said Mark Kozloff, MD, of the University of Chicago, and his colleagues at Weill Medical College of Cornell University, Indiana University Cancer Center, and Pfizer Inc. For more information on the trial, please visit www.suntrials.com.
The combination was generally well tolerated. No new toxicities emerged other than those commonly reported with sunitinib or paclitaxel. Most adverse events were mild or moderate, and no deaths occurred. The most common grade 3 adverse events were fatigue (27%), neutropenia (27% grade 3, 19% grade 4), and diarrhea (14%). Neutropenia was transient and manageable, Dr. Kozloff said. There was no pharmacokinetic interaction between the two agents.