The results from a phase 2 clinical trial to assess the safety and efficacy of axinitib as a first-line treatment for patients with papillary renal cell carcinoma (pRCC) were presented at the European Society of Medical Oncology (ESMO) 2018 Congress in Munich over the weekend.
The majority of renal cell carcinomas (RCCs) are a subtype called clear cell RCC. Most drugs have been developed to treat this subtype of RCC, leaving people with other metastatic RCC subtypes with an unmet need for an effective treatment in the first-line. Papillary RCC represents 10-15% of renal cell carcinomas, and is not an insignificant subtype. Currently, there is no standard treatment for people with metastatic pRCC, and few trials have been conducted. Trials with sunitinib, everolimus and, more recently, savolitinib had disappointing response rates.
In the current clinical trial, the vascular endothelial growth factor (VEGF) inhibitor, axitinib, was investigated as a potential treatment for metastatic pRCC in the first-line. Axitinib is currently available as a second-line treatment for metastatic RCC.
Forty-four patients with type 1 (12 patients), type 2 (30 patients), or mixed/undetermined (2 patients) papillary RCC were treated with axitinib in the study. Median progression-free survival (PFS) was 23.8 weeks for all patients in the study (21.0 for Type 1 and 23.8 for Type 2) and median overall survival (OS) was 18.9 months (NR for Type 1 and 17.4 for Type 2). The safety profile of axitinib was as expected from previous studies.
In conclusion, axitinib shows encouraging efficacy in people with metastatic pRCC, especially in type 2 pRCC. Axitinib toxicity was manageable and as expected from previous clinical trials. Axitinib could be combined with immunotherapy drugs in future clinical trials for metastatic pRCC.