Docetaxel with or without ramucirumab after immune checkpoint inhibition in platinum-refractory metastatic urothelial carcinoma (mUC): Prespecified subgroup analysis from the phase 3 RANGE trial.

434 Background: Immune checkpoint inhibitors (ICI) targeting PD-1/PD-L1 have shown objective response rates (ORR) of 15-21% in PD-L1 unselected patients (pts) with platinum-refractory mUC. Overall results of RANGE, a randomized, double-blinded phase 3 trial comparing ramucirumab and docetaxel (R+D) to placebo and docetaxel (P+D) in pts with platinum-refractory mUC demonstrated an ORR of 24.5% to R+D and a statistically significant improvement in progression free survival (PFS; median 4.07 vs 2.76 mo; HR 0.757). Here we present a pre-specified subgroup analysis of pts who received a prior ICI. Methods: RANGE enrolled pts with progressive mUC during or after platinum-based chemotherapy. Additional prior treatment with one ICI was permitted. Pts were randomized (1:1) to receive D 75 mg/m 2 up to 10 cycles with R 10 mg/kg or P on day 1 of a 21-day cycle until disease progression or other discontinuation criteria. Primary endpoint, investigator-assessed PFS, was analyzed in the first 437 randomized pts. Secondary endpoints included overall survival, objective response, and safety. Radiographic assessment occurred every 6 weeks. Results: Thirty three of the 437 pts (8%) in the PFS population received a prior ICI. The majority (91%) received the ICI immediately following platinum and immediately prior to RANGE. Most pts received atezolizumab (55%) or pembrolizumab (36%); ORR to prior ICI was 6% and the majority (67%) had progressive disease as best response. Median duration of the ICI was 3.5 mo (IQR 1.6-5.2). Disease sites at entry onto RANGE included lymph node (79%), lung (48%), liver (39%) and bone (18%). At data cutoff, responses were achieved by 5/14 (35.7%) on R+D, compared to 2/19 (10.5%) on P+D. Responses to R+D were independent of disease site. Of pts with liver metastases, 3/8 responded to R+D compared to 0/5 on P+D. Overall, median PFS was 5.29 mo on R+D and 2.76 mo on P+D (HR 0.920). The frequency of grade ≥3 adverse events was similar between arms. Conclusions: Acknowledging limitations of sample size, R+D showed higher ORR than P+D in pts who had progressed on platinum and ICI therapy, including those with liver metastases. Clinical trial information: NCT02426125.