Pazopanib showed similar efficacy but better toxicity profile than sunitinib in first line treatment of metastatic RCC. This study reviewed and compared the efficacy and side effects when using these two drugs in Chinese populations. It identified prognostic factors which help predict response in treatment.
This retrospective, single-institutional review included 49 Chinese patients with histologically confirmed RCC between January 2009 and March 2015. Patients received either sunitinib in 6-week cycles (50mg once daily for 4 weeks followed by 2 weeks rest; 36 patients) or pazopanib (800mg once daily; 13 patients) as first line treatment. Kaplan-Meier methods were performed for progression-free survival (PFS). Cox proportional hazard models were constructed to identify clinical and pathological prognostic factors in predicting treatment failure. Adverse events in both groups were compared.
Median follow up was 24.1 months. Median age was 59.9 years (Range 54.7 to 61.7 years). 39 patients (79.6%) had clear cell carcinoma. Median PFS in patients using pazopanib and sunitinib was 10.64 months and 6.34 months respectively while overall survival was 46.00 and 16.69 months respectively. Univariable and multivariable analyses identified history of nephrectomy [Hazard Ratio (HR) = 0.213; 95% CI = 0.068-0.661; p =0.007], baseline neutrophil to lymphocyte ratio (NLR) [HR = 1.294; 95%CI = 1.069-1.567; p = 0.008], baseline serum creatinine [HR = 1.008; 95% CI = 1.002-1.004; p = 0.01] as independent prognostic factors for PFS. Patients treated with sunitinib had a higher incidence of fatigue (47 % vs 23 %), the hand-foot syndrome (61 % vs 46 %) and all grades of leukopenia (75% vs 46%), thrombocytopenia (89% vs 39%), neutropenia (78% vs 54%) and lymphocytopenia (92% vs 62%). Both drugs had similar incidence of diarrhea, mucositis and skin discolouration. Pazopanib showed higher incidence of increased serum aspartate aminotransferase of all grades (77% vs 61 %).
Pazopanib demonstrated a better side effects profile and efficacy as first line treatment than sunitinib in our population. We also identified history of nephrectomy, baseline NLR and serum creatinine as significant prognostic factors.
Clinical trial identification
All authors have declared no conflicts of interest.