Lam, Selay

Introduction Age correlates with survival in patients (pts) with DLBCL, which has a median age at diagnosis of 67 y. Recent therapeutic advances, including bispecifics and cell therapy, have promising efficacy, but safety and accessibility continue to be limited for older pts. The randomized, global, phase 3 ECHELON-3 study (NCT04404283) demonstrated a statistically significant and clinically meaningful improvement in overall survival (OS), progression-free survival (PFS), and overall response rate (ORR) with brentuximab vedotin (BV) + lenalidomide (Len) + rituximab (R; BV+Len+R) vs placebo+Len+R in pts with R/R DLBCL after ≥ 2 prior systemic therapies who were ineligible for hematopoietic stem cell transplant and/or chimeric antigen receptor (CAR) T-cell therapy. Here, we present safety and efficacy in pts aged ≥65 y. Methods In ECHELON-3, pts were randomized 1:1 to receive BV (1.2 mg/kg) or placebo every 3 weeks (q3w), in combination with R (375 mg/m2) q3w and Len (20 mg) once daily. Granulocyte colony-stimulating factor was required in all cycles. Efficacy was assessed by investigators per Lugano 2014 classification. The primary endpoint was OS, with key secondary endpoints of PFS and ORR. Other secondary endpoints included detailed safety and tolerability. This subgroup analysis comprises pts aged ≥65 y. P values are descriptive. Results A total of 155 pts aged ≥65 y were enrolled from April 2021 to November 2023 and randomized to BV+Len+R (n=79) or placebo+Len+R (n=76). The median age was 75 y (range, 65-89 y); 54% of pts were male, 59% were White, and 19% were Asian. Twenty-three percent and 54% had Ann Arbor stage III and IV disease, respectively, and 64% had high-intermediate or high International Prognostic Index scores (3-5) at enrollment. The most common DLBCL subtype was DLBCL not otherwise specified (58%). Twenty-nine percent of pts had transformed DLBCL. Approximately half (49%) of pts had primary refractory disease, and 81% had disease refractory to their most recent prior line of therapy. Seventy percent of pts had <1% CD30 expression via IHC; 48% of cases had germinal center B-cell origin. Prior CAR-T was reported in 21.9% of pts. At a median follow-up of 16.8 mo (95% CI, 14.3-19.5 mo), median OS was 15.9 mo (95% CI, 11.7 mo-not estimable [NE]) with BV+Len+R vs 8.5 mo (95% CI, 5.5-11.5 mo) with placebo+Len+R (hazard ratio [HR], 0.540; 95% CI, 0.351-0.830; P=.0043). Median PFS was 5.7 mo (95% CI, 4.1-12.7 mo) with BV+Len+R vs 2.8 mo (95% CI, 1.9-4.1 mo) with placebo+Len+R (HR, 0.478; 95% CI, 0.318-0.718; P=.0003). ORR was 70.9% (95% CI, 59.6%-80.6%) with BV+Len+R vs 46.1% (95% CI, 34.5%-57.9%) with placebo+Len+R (P=.0020); complete response (CR) rate was 45.6% vs 19.7%, respectively. Median time to CR was 1.61 mo with both BV+Len+R and placebo+Len+R (range, 1.2-7.3 vs 0.7-4.6 mo, respectively). Median duration of CR was 18.9 mo (95% CI, 12.4 mo-NE) with BV+Len+R vs 5.4 mo (95% CI, 2.8 mo-NE) with placebo+Len+R (HR, 0.416; 95% CI, 0.139-1.250). In total, 154 pts were evaluable for safety analysis (75 pts in placebo+Len+R group). The median number of cycles was 5 (range, 1-34) vs 3 (range, 1-31) in the BV+Len+R and placebo+Len+R groups, respectively. The percentage of pts with any treatment-emergent adverse event (TEAE) was similar between groups (97% with BV+Len+R and 99% with placebo+Len+R); grade ≥3 TEAEs occurred in 89% of pts in the BV+Len+R group and 76% in the placebo+Len+R group. Serious TEAEs and TEAEs leading to death were reported more frequently in the BV+Len+R group (62% and 13%, respectively) than the placebo+Len+R group (47% and 8%, respectively). More pts discontinued study treatment due to TEAEs in the BV+Len+R group than the placebo+Len+R group (20% vs 8%). In total, 39% of pts on BV+Len+R had a peripheral neuropathy event vs 27% of pts on placebo+Len+R; however, the majority of cases were grade 1 (22% and 17%, respectively). Additional information on older pts will be presented. Conclusions BV+Len+R demonstrated a clinically meaningful improvement in all key efficacy outcomes in pts aged ≥65 y, which is consistent with the overall ECHELON-3 population (median age 74 y; 70.5% of pts aged ≥65 y in BV+Len+R group). Differences in some safety endpoints are likely attributable to longer duration of treatment in the BV+Len+R group. No clinically meaningful safety trends in pts aged ≥65 y were identified. These results suggest that BV+Len+R may be an effective treatment option in older pts with R/R DLBCL.

CCTG CLC.2/Alliance A041202 demonstrated superior progression-free survival at 2 years with ibrutinib alone (87%; HR 0.39) or ibrutinib-rituximab (IR 88%; HR 0.38) compared to chemo-immunotherapy with bendamustine-rituximab (BR 74%) in treatment-naïve patients (pts) with chronic lymphocytic leukemia (CLL) who were 65 or older (Woyach NEJM 2018). We hypothesized that ibrutinib-based therapies would be more costly than BR but that costs would be offset by less toxicity and improved quality of life (QOL). We completed a prospective trial-based economic analysis to study the direct medical costs and quality-adjusted benefit associated with ibrutinib-based therapies compared to BR in the Canadian (CDN) subset of patients enrolled in CLC.2/Alliance 041202. All CDN pts were invited to participate in the companion analysis. Health utilities were collected using the EuroQOL EQ-5D and calculated using CDN population valuations (Bansback PLOS One 2012). Resource utilization forms were administered to collect off-protocol health care encounters. The planned analysis was a cost-utility analysis from the perspective of a public healthcare system, examining the costs and outcomes (quality-adjusted life years or QALYs) of ibrutinib-based therapy compared to BR. Unit costs were applied to resource data based on publicly available provincial/national databases; all costs were expressed in 2019 US dollars (1 CDN = 0.75 US dollar). Total and disaggregated direct medical costs are presented descriptively. Mean survival was calculated using the restricted mean survival method from randomization to the study time-horizon of 24 months; derived utilities were used to calculate QALYs. A discount rate for costs and benefits (r=0.05) was applied. The analysis was based on estimation (with bootstrapping) of an incremental cost-effectiveness ratio (ICER) and/or direct medical costs. A total of 55 pts were enrolled; two pts who did not receive any treatment were censored at day 1 and 3 after randomization and excluded from analysis. Of the 53 analysed, pt demographics were well balanced between treatments and were reflective of the entire population: mean age was 71.6 (SD 6.34) in pts receiving ibrutinib alone (n=17), 72.2 (SD 3.85) in pts receiving IR (n=18), and 71.7 (SD 4.1) in pts receiving BR (n=18). A total of 3 pts, one in each arm, had 17p deletion. Progression-free survival at 2 years for CDN pts was 94% (95% CI 65-99%) for ibrutinib, 100% (95% CI 100-100%) for IR, and 72% (95% CI 45-87%) for BR (Figure 1). At 24 months, 1 pt on the BR arm had crossed over to ibrutinib (as per protocol); there was no overall survival difference between the three arms. On-protocol costs (including protocol treatment, ambulatory care, and imaging) and off-protocol costs (including hospitalizations, concomitant medications, and ambulatory care) are highlighted in Figure 2. On-protocol costs were higher for pts receiving ibrutinib (mean $142,001 USD; SD 48,417) and IR ($164,931; SD 46,208) compared to BR ($38,509; SD 10,351), driven by higher drug acquisition costs associated with ibrutinib (list price $6422 for 420mg/30 days). In contrast, off-protocol costs were modestly higher for pts on BR (mean $3050; SD 3812) compared to the ibrutinib ($2460; SD 3863) or IR ($2890; SD 4206); hospitalizations were the key off-protocol cost drivers and were highest for pts on IR and BR. Overall mean costs over the 2-year time horizon were $144,461 (SD 47,910) for pts on ibrutinib, $167,820 (SD 46,830) for pts on IR, and $41,560 (SD 11,849) for pts on BR. Discounted QALYs were similar between the three treatment arms: 1.66 (0.16) for ibrutinib alone, 1.65 (0.24) for IR, and 1.66 (0.17) for BR. Given the similar quality-adjusted survival between arms at the time of this analysis, a formal ICER was not calculated. Direct medical costs are substantially higher for pts receiving continuous ibrutinib-based therapies, compared to chemo-immunotherapy of fixed duration, in frontline CLL management; the key cost driver is the cost of ibrutinib. The PFS benefit with ibrutinib-based therapy has not translated into an advantage in quality-adjusted survival to date; further follow-up may be required to demonstrate any cost or QOL benefits associated with fewer progression events for those on ibrutinib. Support: U10CA180821, U10CA180882; U10CA180863 and #704970 CCTG. https://acknowledgments.alliancefound.org ClinicalTrials.gov: NCT01886872 Figure Disclosures Owen: AbbVie, F. Hoffmann-La Roche, Janssen, Astrazeneca, Merck, Servier, Novartis, Teva: Honoraria. Lam:Roche: Honoraria, Speakers Bureau; Janssen: Honoraria, Speakers Bureau. Crump:Servier: Consultancy; Kite/Gilead: Consultancy; Roche: Consultancy. Sperlich:Lundbeck Canada: Honoraria. Woyach:Pharmacyclics, Janssen, Morphosys, Karyopharm, Verastem, Abbvie, Lox: Research Funding; Janssen, Pharmacyclics, AstraZeneca, Abbvie, Arqule: Consultancy; Pharmacyclics LLC, an AbbVie Company, AbbVie, Janssen, AstraZeneca, ArQule: Honoraria. Prica:astra zeneca: Honoraria; seattle genetics: Honoraria; Gilead: Honoraria. Hay:Roche: Research Funding; Janssen: Research Funding.