LAUSR

BACKGROUND Nivolumab-ipilimumab demonstrated a survival benefit over sunitinib in first-line setting for metastatic renal cell carcinomas (mRCCs) and is becoming a new standard of care for naïve patients with intermediate or poor risk prognosis (International mRCC Database Consortium). The efficacy of subsequent vascular endothelial growth factor receptor tyrosine kinase inhibitors (TKIs) after nivolumab-ipilimumab failure remains unclear. METHODS Medical records of mRCC patients treated with nivolumab-ipilimumab, who received subsequent TKI, as part of Checkmate 214 study were reviewed in 13 institutions. Baseline characteristics, outcome data including progression-free survival (PFS), response, overall survival (OS) and toxicities were retrospectively collected. RESULTS Overall 33 patients received subsequent TKI after nivolumab-ipilimumab failure. Median follow-up from start of subsequent TKI is 22 months (19-NR). Best response was assessed in 30 patients: 12 partial responses (36%), 13 stable diseases (39%) and five progressive diseases (15%). Median PFS from start of TKI was 8 months [5-13]. Median PFS with first-generation (sunitinib/pazopanib) and second-generation TKI (axitinib/cabozantinib) was 8 months [5-16] and 7 months (5-NA), respectively. PFS in second line was significantly longer in patients with a long first-line duration of response to the double immune checkpoint blockade (≥6 months) with 8 versus 5 months for short responder (<6 months) (p = 0.03). OS rate was 54% at 12 months. Toxicity was as expected: 42% developed at least one toxicity grade ≥3. CONCLUSION This is the first report of outcomes with TKI, after first-line nivolumab-ipilimumab failure. Median PFS suggests a sustained benefit of TKI and supports trials investigating the optimal sequence.