Pfizer halts Sutent versus Avastin breast cancer trial

Pfizer has decided to terminate a late-stage trial of Sutent plus paclitaxel in advanced breast cancer as it would not meet its primary goal.

Specifically, the company said that the SUN 1094 Phase III study that evaluated Sutent (sunitinib) plus paclitaxel versus Roche’s blockbuster Avastin (bevacizumab) plus paclitaxel for the first-line treatment of patients with advanced breast cancer has been halted. The decision has been taken after an independent data monitoring committee found that the combo would be unable to meet the primary endpoint of superior progression-free survival (PFS) compared to the combination of bevacizumab and paclitaxel. No new safety issues were identified.

Mace Rothenberg at Pfizer’s Oncology Business Unit said that “while we are disappointed that this trial did not meet its primary endpoint, we are continuing to study sunitinib in different breast cancer populations and with different regimens”. The firm is conducting two other late-stage studies of Sutent, the first comparing sunitinib with a different chemotherapy docetaxel to docetaxel alone in advanced breast cancer.

The other is looking at Sutent and Xeloda (capecitabine) against capecitabine as a secondary treatment for breast cancer. Data from the two trials are expected later this year or in early 2010.

Sutent is approved to treat advanced renal cell carcinoma, and gastrointestinal stromal tumours for patients who can't tolerate Novartis’ Glivec/Gleevec (imatinib). Pfizer is also performing Phase III studies of the drug in advanced non-small cell lung, colorectal and prostate cancers, as well as in hepatocellular carcinoma.