Promising results from phase I study of Genentech's GDC-0941 for advanced breast cancer

Promising results of PI3K inhibitor study discussed at ASCO annual meeting

A new drug targeting the PI3K gene in patients with advanced breast cancer shows promising results in an early phase I investigational study conducted at Virginia G. Piper Cancer at Scottsdale Healthcare, according to a presentation by oncologist Dr. Daniel D. Von Hoff at the 47th annual meeting of the American Society of Clinical Oncology (ASCO).

The drug under investigation, GDC-0941, manufactured by Genentech Inc., South San Francisco, Calif., targets the PI3K gene, which is abnormal in about 20-30 percent of patients with advanced breast cancer.

In collaboration with the Karmanos Cancer Institute in Detroit, Mich. and the Dana-Farber Cancer Institute in Boston, Mass., Dr. Von Hoff and his team at Virginia G. Piper Cancer Center Clinical Trials initially tested the drug in 97 patients with various advanced cancers. Patients experienced manageable side effects including diarrhea, nausea, taste alteration, rash, fatigue, itchiness, vomiting and decreased appetite.

The study resulted in significant shrinkage of tumors in two patients - one with advanced cervical cancer and one with advanced breast cancer. Another patient with ampullary cancer of the pancreas is currently on the study with stable disease for more than a year.

Dr. Von Hoff is Physician-In-Chief and Distinguished Professor at the Translational Genomics Research Institute (TGen), Chief Scientific Officer at Scottsdale Healthcare and US Oncology. Virginia G. Piper Cancer Center Clinical Trials is a partnership between TGen and Scottsdale Healthcare that treats cancer patients with promising new drugs through clinical trials at the Virginia G. Piper Cancer Center in Scottsdale, Ariz.

"We are very excited about personalizing therapy for breast cancer and gynecologic cancer patients with PI3K inhibitors," said Dr. Von Hoff, who made his presentation in June during ASCO's annual meeting in Chicago. "The next step will be to test samples from breast cancer patients for PI3K mutations and treat those patients accordingly."