Aims: In the phase 3 JAVELIN Bladder 100 trial (NCT02603432), avelumab 1L maintenance + best supportive care (BSC) significantly prolonged overall survival (OS) vs BSC alone in patients with advanced UC that had not progressed with 1L platinum-based chemotherapy. Data on outcomes in patients who receive 2L treatment after avelumab 1L maintenance are limited. We report exploratory analyses of outcomes in patients enrolled in the avelumab + BSC arm of JAVELIN Bladder 100 based on receipt of 2L treatment administered by investigators after discontinuation of study treatment.
Methods: Eligible patients had unresectable locally advanced or metastatic UC without progression with 4-6 cycles of 1L platinum-based chemotherapy. Patients were randomized 1:1 to receive avelumab + BSC or BSC alone.
Results: In the avelumab + BSC arm (n=350), median follow-up (data cutoff, June 4, 2021) was 38.0 months. 185 patients (52.9%) had discontinued avelumab 1L maintenance treatment for any reason and received 2L treatment, whereas 122 (34.9%) had discontinued avelumab and did not receive 2L treatment. Median OS (95% CI) in these subgroups was 19.9 months (18.2-23.0) and 18.2 months (10.0-34.4), respectively. In 43 patients (12.3%) still receiving avelumab, median treatment duration was 154.6 weeks (range, 106.7-216.0). Among patients who received 2L treatment, median time from end of avelumab 1L maintenance to start of 2L treatment was 1.35 months (range, 0.3-30.9) and median time from randomization to end of 2L treatment was 11.7 months (95% CI, 9.7-13.8). 2L treatment comprised rechallenge with platinum-based chemotherapy in 75 patients (21.4%) or other 2L treatment in 110 (31.4%), including 2L anti–PD-(L)1 therapy in 11 (3.1%).
Conclusions: In this exploratory analysis from JAVELIN Bladder 100 with extended follow-up, 185/307 patients (≈60%) who had discontinued avelumab received 2L treatment. Long-term OS was observed in patients who received avelumab 1L maintenance with or without 2L treatment.