A regimen that combines Genentech’s Avastin and Tarceva has shown an encouraging increase in progression-free survival in a Phase II trial involving patients with advanced non-squamous non-small-cell lung cancer (NSCLC).

Avastin (bevacizumab) is Genentech’s vascular endothelial growth factor (VEGF) monoclonal antibody, already sold for colorectal cancer, while Tarceva (erlotinib) is the firm’s recently-introduced epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor for lung and pancreatic cancers.

Preliminary results from the 80-patient study found that the combination, given on top of standard chemotherapy, seemed to be more effective than Avastin plus chemotherapy or chemotherapy alone.

Patients who were treated second-line with Avastin and Tarceva had a median progression-free survival of 4.8 months, versus 4.4 months for Avastin plus chemotherapy and 3 months for chemotherapy alone.

The six-month progression-free survival rate was 33.6% in the Avastin/Tarceva arm versus 30.5% in the Avastin-chemotherapy arm and 21.5% in the control arm, although the differences did not reach statistical significance in this small study.

The investigators, led by Roy Herbst from the University of Texas in Houston, USA, also report that the toxicity profile of the combination also appeared to favourable compared to the two other regimens.

Two Phase III trials are currently underway to explore the potential value of Avastin plus Tarceva in NSCLC patients.

Avastin are two rising stars in Genentech’s oncology portfolio, bringing in sales of $435 million (up 34% but a little shy of analysts’ expectations) and $100 million (up 37%), respectively, in the third quarter of 2006. They are sold by Genentech’s majority shareholder Roche outside the USA.