BioSpace has reported the main results from a Phase III study comparing axitinib to sorafenib in the treatment of patients with previously-treated advanced renal cell carcinoma (RCC), due for presentation at the 47th Annual American Society of Clinical Oncology (ASCO) meeting in June 2011.

Axitinib is an investigational oral inhibitor of vascular endothelial growth factor (VEGF) receptors 1, 2 and 3.  The AXIS 1032 study randomised 723 patients with clear-cell RCC who had progressed following prior therapy with regimens containing sunitinib (54%), cytokines (35%), bevacizumab (8%) or temsirolimus (3%) to treatment with axitinib (5mg BD; n=361) or sorafenib (400mg BD; n=362).  The primary endpoint was progression-free survival (PFS) – this was prolonged by 2 months in the axitinib group (median of 6.7 months (95%CI 6.3-8.6) versus 4.7 months (4.6-5.6) for sorafenib; HR=0.665; P<0.0001).  PFS was longer in the axitinib group for both the prior cytokine-treated subgroup (12.1 vs. 6.5 months; P<0.0001) and the prior sunitinib-treated subgroup (4.8 vs. 3.4 months; P=0.0107).  The objective response rates (assessed by independent central review) were 19.4% in the axitinib group and 9.4% in the sorafenib group (P=0.0001).  The following common adverse events occurred more frequently in the axitinib group: hypertension (40%), fatigue (39%), dysphonia (31%), and hypothyroidism (19%).

As well as previously-treated RCC, axitinib is being investigated in a Phase III clinical trial in patients with treatment-naïve RCC, and in a randomised Phase II clinical trial for the treatment of hepatocellular carcinoma.