Genentech’s Phase III colon cancer trial fails primary endpoint

Genentech has reported that a Phase III study of Avastin plus chemotherapy following surgery in patients with early-stage colon cancer did not meet its primary endpoint of reducing the risk of cancer returning. Results are from a planned final analysis of the study.

This is the first trial of Avastin in early-stage cancer and results do not affect approved indications in advanced disease, the company said.

The C-08 study was conducted by the National Surgical Adjuvant Breast and Bowel Project (NSABP) and sponsored by the National Cancer Institute (NCI) under a co-operative R&D agreement between Genentech and NCI.

NSABP C-08 is a randomized multi-center Phase III study designed to evaluate the effect of Folfox chemotherapy with or without Avastin on disease-free survival in patients with resected stage II or III adenocarcinoma of the colon. The trial was conducted primarily in the US.

Patients enrolled in the two-arm study were randomized after surgery to receive either Folfox chemotherapy alone for six months or Folfox in combination with Avastin for six months, followed by an additional six months of Avastin monotherapy. The secondary endpoint of the study was overall survival.

Results are expected in 2010 from a separate Roche-sponsored international Phase III study (Avant) assessing Avastin in combination with chemotherapy for early-stage colon cancer. The three-arm trial is evaluating Avastin in combination with the chemotherapy regimens Xelox or Folfox chemotherapy versus Folfox alone.

Hal Barron, senior vice president of development and chief medical officer of Genentech, said: While we are disappointed the C-08 study did not meet its primary endpoint, our initial review of the data leads us to continue to believe Avastin may be active in patients with early-stage colon cancer. We remain fully committed to the ongoing Avastin adjuvant programs in early-stage colon, breast and lung cancers.