Results from the phase 3 PROTECT clinical trial, which compared the efficacy of pazopanib with placebo in people with locally-advanced kidney cancer after surgery (adjuvant therapy), showed no significant improvement over placebo in disease-free survival. This comes on the back of the S-TRAC and ASSURE clinical trials, which looked at other VEGF-TKIs as adjuvant therapy. S-TRAC compared adjuvant treatment with sunitinib versus placebo, and was positive for disease-free survival, but has not shown an improvement in overall survival to date. The ASSURE trial compared sorafenib, sunitinib, and placebo and showed no benefit in either disease-free survival or overall survival.
However, in the PROTECT study there seemed to be a benefit in disease-free survival at the higher dose of 800 mg of pazopanib. This dose was not well tolerated and patients who received it were removed from the primary analysis. The researchers suggest that dose intensity may potentially play a role in adjuvant therapy, but it remains to be seen whether or not these treatments will ultimately yield what is perhaps the most crucial outcome—an improvement in overall survival.