Pfizer reports that its Phase III trial studying axitinib in previously treated metastatic renal cell carcinoma (mRCC) patients has met its primary endpoint. The trial demonstrated that axitinib significantly extended progression-free survival when compared to sorafenib. Axitinib demonstrated a generally manageable safety profile, the firm reports.
“These results provide insight into the potential value of axitinib as part of a sequential treatment approach in patients with advanced RCC,” says Mace Rothenberg, M.D., svp of clinical development and medical affairs for Pfizer's oncology business unit.
Axitinib is an oral and selective inhibitor of vascular endothelial growth factor (VEGF) receptors 1, 2, and 3. These receptors appear to have roles in tumor growth, vascular angiogenesis, and metastatic progression.
In February 2009, Pfizer axed Phase III trials of axitinib in advanced pancreatic cancer. During an interim analysis the independent Data Safety Monitoring Board found no evidence of improvement in the primary endpoint of survival in patients treated with axitinib and gemcitabine compared to gemcitabine alone.
Pfizer says that it will continue to investigate the role of axitinib across other tumor types. This includes Phase II studies in lung and thyroid cancers.
Pfizer offers two approved therapies for the treatment of advanced RCC, Sutent® (sunitinib malate) and Torisel® (temsirolimus). Sutent is an oral multikinase inhibitor and is also approved for the treatment of GIST after disease progression on or intolerance to imatinib mesylate. Torisel is an mTOR inhibitor.