Phase I/II study of avadomide (CC-122) in combination with R-CHOP for newly diagnosed DLBCL.

Abstract

3501 Background: In certain subsets of patients (pts) with diffuse large B-cell lymphoma (DLBCL), the failure rate of standard R-CHOP treatment is high. Pts with high-risk disease (International Prognostic score [IPI] 3-5) have a particularly poor prognosis, with 3-y survival rates of ~62% with R-CHOP alone. The cereblon E3 ligase modulator avadomide (CC-122) showed activity in pts with relapsed or refractory DLBCL. We report results of avadomide plus R-CHOP in previously untreated pts with high-risk DLBCL. Methods: CC-122-DLBCL-002 (NCT03283202) is a phase 1/2 study of avadomide plus R-CHOP-21 in pts newly diagnosed with DLBCL not otherwise specified with IPI scores 3-5 who were aged ≥18 y. Pts received standard R-CHOP and escalating doses (1-3 mg) of oral avadomide for up to six 21-d cycles (Table). All pts received pegfilgrastim support. Primary objectives were to assess safety, tolerability, and complete response (CR) rate. Secondary objectives include evaluation of additional efficacy parameters (objective response rate [ORR], progression-free survival [PFS], and overall survival) and biomarkers. Results: As of July 30, 2019, 35 pts were enrolled in the phase 1 part of the study. Median age was 66 y (range, 20-75), 23 pts (66%) were aged > 60 y, 18 (51%) had an IPI score of 3, and 17 (49%) had an IPI score of 4-5. Thirty-two pts (91%) completed 6 cycles of treatment. Median relative total dose intensity of avadomide was 99% and the average relative dose intensity of R-CHOP was 95%. Six pts had dose-limiting toxicities: 1 pt had neutropenia and bacterial hepatic infection; 1 had pneumonia; 1 had febrile neutropenia (FN); 1 had FN and hypotension; 1 had FN due to skin infections; and 1 had sepsis. The recommended phase 2 dose was 3 mg 2/3 wk. Grade 3/4 adverse events in ≥10% of pts were neutropenia (54%), anemia (20%), leukopenia (20%), lymphopenia (14%), hypophosphatemia (14%), and FN (11%). Among 34 efficacy-evaluable pts, the ORR was 88% (n = 30/34), including a CR rate of 79% (n = 27/34) at the end of treatment. With a median follow-up of 10 mo, the 1-y PFS rate was 80% (95% CI, 58-92). Correlative analyses will be presented at the meeting. Conclusions: Avadomide plus R-CHOP was well-tolerated with no significant additive toxicities. The promising efficacy in this high-risk pt population warrants further evaluation of immunomodulatory drugs combined with immunochemotherapy for pts with previously untreated DLBCL. Clinical trial information: NCT03283202 . [Table: see text]