e-Poster Presentation Clinical Oncology Society of Australia Annual Scientific Meeting 2021

Avelumab first-line maintenance for advanced urothelial carcinoma (aUC) in the phase 3 JAVELIN Bladder 100 trial: subgroup analysis by duration of treatment-free interval from end of chemotherapy to start of maintenance (#244)

David W. Pook 1 , Srikala S. Sridhar 2 , Thomas Powles 3 , Yohann Loriot 4 , Miguel A. Climent Durán 5 , Shilpa Gupta 6 , Norihiko Tsuchiya 7 , Aristotelis Bamias 8 , Andrea Ardizzoni 9 , Anders Ullén 10 , Bo Huang 11 , Nuno Costa 12 , Robert J. Laliberte 13 , Alessandra di Pietro 14 , Cora N. Sternberg 15 , Petros Grivas 16
  1. Monash University, Melbourne, Victoria, Australia
  2. Princess Margaret Cancer Center, University Health Network, Toronto, Ontario, Canada
  3. Barts Cancer Institute, Experimental Cancer Medicine Centre, Queen Mary University of London, St Bartholomew’s Hospital, London, United Kingdom
  4. Gustave Roussy, INSERMU981, Université Paris-Saclay, Villejuif, France
  5. Instituto Valenciano de Oncología, Valencia, Spain
  6. Cleveland Clinic, Cleveland, Ohio, United States
  7. Yamagata University Faculty of Medicine, Yamagata, Japan
  8. Alexandra General Hospital, National and Kapodistrian University of Athens, School of Medicine, Athens, Greece
  9. Azienda Ospedaliero-Universitaria Policlinico S.Orsola Malpighi, Bologna, Italy
  10. Genitourinary Oncology Unit, Karolinska University Hospital, Solna, Sweden
  11. Pfizer, Groton, Connecticut, United States
  12. Pfizer, Porto Salvo, Portugal
  13. Pfizer, Cambridge, Massachusetts, United States
  14. Pfizer srl, Milano, Italy
  15. Englander Institute for Precision Medicine, Weill Cornell Medicine, Hematology/Oncology, New York, United States
  16. University of Washington; Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle Cancer Care Alliance, Seattle, Washington, United States

Aims: In the JAVELIN Bladder 100 (NCT02603432) trial, which enrolled patients with aUC not progressing on first-line platinum-containing chemotherapy, avelumab first-line maintenance + best supportive care (BSC) significantly prolonged overall survival (OS) vs BSC alone (HR, 0.69 [95% CI: 0.56, 0.86; 1-sided P=0.0005]). However, optimal timing for starting avelumab after completing chemotherapy is unknown. We report efficacy by duration of treatment-free interval (TFI) after completion of first-line chemotherapy.

Methods: Patients with unresectable locally advanced or metastatic UC without disease progression following 4-6 cycles of first-line platinum-based chemotherapy were randomized to receive avelumab + BSC (n=350) or BSC alone (n=350) after a TFI of 4-10 weeks. This exploratory analysis evaluated subgroups with a TFI of 4 to <6, 6 to <8, or 8 to 10 weeks.

Results: In the avelumab + BSC and BSC alone arms, TFI was 4 to <6 weeks in 143 and 158 patients, 6 to <8 weeks in 109 and 80, and 8 to 10 weeks in 98 and 110, respectively. Baseline characteristics were generally well balanced between arms; however, for both arms combined, the TFI 4 to <6 weeks subgroup vs other subgroups included more patients with visceral metastases, an objective response to first-line chemotherapy, and ECOG performance status of 1. OS was prolonged with avelumab + BSC vs BSC alone in all subgroups (HR, 0.76 [95% CI: 0.546, 1.059] for TFI 4 to <6 weeks; 0.64 [95% CI: 0.404, 1.021] for TFI 6 to <8 weeks; and 0.70 [95% CI: 0.468, 1.035] for TFI 8 to 10 weeks).

Conclusions: Avelumab first-line maintenance prolonged OS irrespective of the TFI assessed in this study (4-10 weeks), further supporting this new treatment strategy as a standard of care. Differences in duration of TFI were likely related to individual patient/disease-specific characteristics or logistics and did not impact OS benefit.

  1. © 2021 American Society of Clinical Oncology, Inc. Reused with permission. This abstract was accepted and previously presented at the 2021 ASCO Annual Meeting. All rights reserved.