Outcomes of PD-1/PD-L1 responders who discontinue therapy for immune-related adverse events (irAEs): Results of a cohort of patients (pts) with metastatic renal cell carcinoma (mRCC).

467Background: Nivolumab, a monoclonal antibody against PD-1, has been shown to improve survival for pts with mRCC. The current standard of care is to administer treatment on a continuous basis until progression or toxicity. Outcomes of pts who experience a response to treatment and then discontinue therapy for irAEs have not been fully characterized. The purpose of this analysis was to evaluate outcomes of responders to PD-1/PD-L1 targeted therapy (TT) who discontinue treatment for irAEs. Methods: We identified pts with mRCC having experienced a response to PD-1/PD-L1 TT, which was subsequently discontinued for an irAE. Clinical characteristics, response, and survival data were collected. Results: We identified 9 mRCC pts who were treated with a PD-1/PD-L1 inhibitor, experienced a response to therapy, and subsequently discontinued treatment for an irAE. 8 had clear cell histology and 1 had translocation RCC. 7 pts were treatment naive. 2 pts had International mRCC Database Consortium favorable risk, 4 in...