Sunitinib Rechallenge in Patients With Metastatic Renal Cell Carcinoma

Sunitinib has been the standard of care for patients with metastatic renal cell carcinoma (mRCC). However, nearly all patients will eventually develop resistance. Before the introduction of novel agents, few treatment options remained after sunitinib failure. Sunitinib rechallenge is a strategy based on the presumption that resistance might be only temporary. The aim of this analysis was to evaluate the efficacy and safety of sunitinib rechallenge in patients with mRCC.

Patients who had undergone sunitinib rechallenge (SU2) at the Medical University of Vienna from 2010 to 2017 were identified for the present retrospective study. The primary endpoint was the treatment duration with rechallenge (TD^SU2). The secondary endpoints included the treatment duration with upfront sunitinib (TD^SU1), progression-free survival (PFS^SU1 and PFS^SU2), overall survival (OS^SU1 and OS^SU2), the objective response rate in both settings (ORR^SU1 and ORR^SU2), and toxicity.

A total of 31 patients were eligible. The median TD^SU2 was 7.2 months, and the median TD^SU1 was 17.8 months. The median OS^SU1 and OS^SU2 was 57.9 months and 14.7 months, respectively. The median PFS^SU1 and PFS^SU2 was 14.2 months and 5.6 months, respectively. The ORR^SU1 and ORR^SU2 was 34% and 16%, and another 48% and 42% achieved stable disease (SD), respectively. Fatigue and hypertension were the most common adverse events.

Sunitinib rechallenge appears to benefit patients in later treatment lines. With the abundance of novel treatment options available, this approach might appear less relevant. However, novel agents are not yet available everywhere. Thus, sunitinib rechallenge could be an additional strategy to improve the outcomes of patients with mRCC.