AVELUMAB MONOTHERAPY FOLLOWED BY A PET ADAPTED CHEMOTHERAPY APPROACH IN THE FIRST LINE TREATMENT OF CLASSICAL HODGKIN LYMPHOMA: INITIAL RESULTS FROM THE AVENUE WINDOW STUDY

Introduction: Inhibitors of programmed cell death receptor 1 (PD1) used with chemotherapy result in high response rates and durable remissions the first line (1L) treatment classical Hodgkin Lymphoma (cHL). Avelumab is an inhibitor immune checkpoint PDL1, which highly expressed by Reed-Sternberg cells, has demonstrated activity relapsed/refractory cHL. The AVENuE window study assessed efficacy safety avelumab prior to adapted as 1L It report on PDL1 inhibition this setting. Financial support was provided investigator sponsored research grant from Pfizer Ltd. Methods: Adult patients (pts) advanced cHL were enrolled phase 2 study. Pts received cycles (4 doses) then underwent a PET/CT followed ABVD (iPET). iPET neg (Deauville score 1–3) pts further 4 × AVD PET pos (DS 4–5), escalated BEACOPP. RATHL results historical comparison. primary endpoint overall rate (complete & partial metabolic response: CMR/PMR) after >40% deemed worthy <20% considered unacceptable (5% 1-sided alpha, 90% power required 47 pts). Response per modified Lugano criteria. Results: eligible. Median age 30 y (range: 17–58); 64% male; 23%, 26% 51% had risk stage II, III IV disease respectively; 60% B symptoms; 40% IPSS >2. 44 completed (2 stopped due toxicity, site concerns over progressive (PD); indeterminate (IR) Lugano). 89% subsequent ABVD/AVD delivered without delay (compared RATHL). Overall 44.7% (90% CI: 32.2–57.7); CMR 11%; PMR 34%. remainder IR. positive 5 (10.6%) (95% CI 3.5–23.1) versus 16.3% IR did not show worse compared responders (87.5% vs. 88.0%). eBEACOPP whom converted subsequently. With median follow up 14 months (range 4–32) there 1y PFS 100% but PDs have been reported at 23 months. Grade 3+ adverse events least possibly related occurred 9 (20%) including one each colitis, pneumonitis, autoimmune hepatitis, renal tubular acidosis reports tumour flare. funded by: Keywords: lymphoma, immunotherapy Conflicts interests pertinent abstract E. A. Hawkes Research funding: Merck KgA