Avelumab Maintenance Yields Survival Benefit in First-Line Advanced Urothelial Carcinoma, Regardless of Second-Line Therapy

Frontline avelumab (Bavencio) maintenance yielded long-term overall survival (OS) in patients with advanced urothelial carcinoma regardless of second-line therapy, according to an exploratory analysis of the JAVELIN Bladder 100 study (NCT02603432) presented at the 2022 American Society of Clinical Oncology (ASCO) Annual Meeting.

The trial previously demonstrated that avelumab first-line maintenance and best supportive care (BSC) significantly prolonged OS compared with BSC alone in patients with advanced urothelial carcinoma that had not progressed with first-line platinum-containing chemotherapy.2,3 For the current study, the investigators performed an exploratory analysis of outcomes in patients in the avelumab plus BSC arm based on receipt of second-line treatment, according to the study’s poster.

Patients in the trial had unresectable locally advanced or metastatic urothelial carcinoma that had not progressed with 4 to 6 cycles of first-line platinum-containing chemotherapy. Patients were randomized 1:1 to receive avelumab maintenance plus BSC or BSC alone after an interval of 4 to 10 weeks from the end of first-line chemotherapy. The study’s primary end point was OS.

“Exploratory analyses of OS and time from randomization to end of second-line treatment were performed in the avelumab plus BSC arm in subgroups defined by second-line treatment administered by investigators after discontinuation of study treatment,” wrote the authors, led by Joaquim Bellmunt, MD, PhD, associate professor of medicine at Harvard Medical School and director of the Bladder Cancer Program at Beth Israel Deaconess Medical Center in Boston, Massachusetts.

Median follow-up in the avelumab arm was 38.0 months at the data cutoff. Of the 350 patients randomized to avelumab plus BSC, 43 (12.3%) were still receiving avelumab first-line maintenance, with a median duration of treatment of 35.6 months (range, 24.5 to 49.7 months); 185 (52.9%) had discontinued treatment with avelumab and moved on to second-line treatment, with a median duration of avelumab treatment of 5.1 months (range, 0.5 to 44.6 months); and 122 (34.9%) had discontinued avelumab and did not receive second-line treatment, with a median duration of avelumab treatment of 5.0 months (range, 0.5 to 43.7 months). The investigators reported that baseline characteristics were similar between patients in the avelumab arm who did or did not receive second-line treatment.

Median OS was not reached in the patients still receiving avelumab, 19.9 months (95% CI, 18.2-23.0) in patients discontinuing avelumab and moving on to second-line treatment, and 18.2 months (95% CI, 10.0-34.4) in patients discontinuing avelumab and not receiving second-line treatment.

In patients receiving second-line treatment, the median time from the end of avelumab maintenance to the start of second-line treatment was 1.35 months (range, 0.3 to 30.9 months). Median time from randomization to the end of second-line treatment was 11.7 months (95% CI, 9.7-13.8).

“Overall, these data…provide new insights about survival in patients receiving avelumab first-line maintenance in the JAVELIN Bladder 100 trial with or without second-line treatment, and these data further support the benefits of the sequence of first-line platinum-based chemotherapy followed by avelumab maintenance,” Bellmunt said in his concluding remarks.

References

1. Bellmunt J, Powles T, Climent Durán MÁ, et al. Long-term outcomes in patients with advanced urothelial carcinoma (UC) who received avelumab first-line (1L) maintenance with or without second-line (2L) treatment: Exploratory analyses from JAVELIN Bladder 100. J Clin Oncol 2022;40(suppl 16):4560. doi:10.1200/JCO.2022.40.16_suppl.4560
2. Powles T, Park SH, Voog E, et al. Avelumab maintenance therapy for advanced or metastatic urothelial carcinoma. N Engl J Med. 2020;383(13):1218-1230.doi:10.1056/NEJMoa2002788
3. Powles T, Park SH, Voog E, et al. Avelumab first-line (1L) maintenance for advanced urothelial carcinoma (UC): Long-term follow-up results from the JAVELIN Bladder 100 trial. J Clin Oncol 2022;40(suppl 6):487. doi:10.1200/JCO.2022.40.6_suppl.487