Abstract: Rituximab improves outcomes for persons with lymphoproliferative disorders and is increasingly used to treat immune-mediated illnesses. Recent reports describe 2 patients with systemic lupus erythematosus and 1 with rheumatoid arthritis who developed progressive multifocal leukoencephalopathy (PML) after rituximab treatment. We reviewed PML case descriptions among patients treated with rituximab from the Food and Drug Administration, the manufacturer, physicians, and a literature review from 1997 to 2008. Overall, 52 patients with lymphoproliferative disorders, 2 patients with systemic lupus erythematosus, 1 patient with rheumatoid arthritis, 1 patient with an idiopathic autoimmune pancytopenia, and 1 patient with immune thrombocytopenia developed PML after treatment with rituximab and other agents. Other treatments included hematopoietic stem cell transplantation (7 patients), purine analogs (26 patients), or alkylating agents (39 patients). One patient with an autoimmune hemolytic anemia developed PML after treatment with corticosteroids and rituximab, and 1 patient with an autoimmune pancytopenia developed PML after treatment with corticosteroids, azathioprine, and rituximab. Median time from last rituximab dose to PML diagnosis was 5.5 months. Median time to death after PML diagnosis was 2.0 months. The case-fatality rate was 90%. Awareness is needed of the potential for PML among rituximab-treated persons.

Abstract: Effective and tolerable treatments are needed for older patients with classical Hodgkin lymphoma. We report results for older patients with classical Hodgkin lymphoma treated in the large phase III ECHELON-1 study of frontline brentuximab vedotin plus doxorubicin, vinblastine, and dacarbazine (A+AVD) versus doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD). Modified progression-free survival per independent review facility for older versus younger patients (aged ≥60 vs. 〈 60 years) was a pre-specified subgroup analysis; as the ECHELON- 1 study was not powered for these analyses, reported P-values are descriptive. Of 1,334 enrolled patients, 186 (14%) were aged ≥60 years (A+AVD: n=84, ABVD: n=102); results below refer to this age group. Modified progression-free survival per independent review facility was similar in the two arms at 24 months (A+AVD: 70.3% [95% confidence interval (CI): 58.4–79.4], ABVD: 71.4% [95% CI: 60.5–79.8] , hazard ratio (HR)=1.00 [95% CI: 0.58–1.72], P=0.993). After a median follow-up of 60.9 months, 5-year progression-free survival per investigator was 67.1% with A+AVD versus 61.6% with ABVD (HR=0.820 [95% CI: 0.494–1.362] , P=0.443). Comparing A+AVD versus ABVD, grade 3/4 peripheral neuropathy occurred in 18% versus 3%; any-grade febrile neutropenia in 37% versus 17%; and any-grade pulmonary toxicity in 2% versus 13%, respectively, with three (3%) pulmonary toxicity-related deaths in patients receiving ABVD (none in those receiving A+AVD). Altogether, A+AVD showed overall similar efficacy to ABVD with survival rates in both arms comparing favorably to those of prior series in older patients with advanced-stage classical Hodgkin lymphoma. Compared to ABVD, A+AVD was associated with higher rates of neuropathy and neutropenia, but lower rates of pulmonary-related toxicity. Trials registered at ClinicalTrials.gov identifiers: NCT01712490; EudraCT number: 2011-005450-60.

Abstract: Background Survival rates for older pts with advanced HL (aged ≥60 yrs) were historically poor with doxorubicin, bleomycin, vinblastine and dacarbazine (ABVD). Reasons may include decreased tolerance of therapy, increased toxicity (particularly with bleomycin), comorbidities, and disease biology. The pivotal phase 3 ECHELON-1 study demonstrated superior 2-yr modified progression-free survival (mPFS) with frontline brentuximab vedotin + doxorubicin, vinblastine and dacarbazine (A+AVD) vs ABVD in pts with stage III/IV cHL (Connors JM et al, NEJM 2018). The study allowed entry of older pts, with no upper age limit. Alternative dosing schedules of the A+AVD regimen have been studied (e.g., sequential brentuximab vedotin before and after AVD; NCT01476410, Evens AM et al, J Clin Oncol 2018). We report efficacy and safety results from ECHELON-1 for older pts with cHL and compare these with those for pts aged 〈 60 yrs. Methods mPFS per independent review facility (IRF) for pts ≥60 years was a prespecified subgroup analysis of ECHELON-1. Additional exploratory safety and efficacy analyses were also assessed and compared with younger pts ( 〈 60 yrs). The study was not powered for age-based subgroup analyses; p-values are descriptive without multiplicity adjustment. Results 14% (186/1334) of pts in the intent-to-treat (ITT) population were aged ≥60 yrs (A+AVD, n=84; ABVD, n=102) and included in the sub analyses. Median age (range) of older pts was: A+AVD, 68.0 yrs (60-82); ABVD, 66.0 yrs (60-83). Baseline pt and disease characteristics in older pts were similar in both arms. ECOG PS scores were 0 (36% vs 36%), 1 (52% vs 54%), and 2 (12% vs 10%) in A+AVD and ABVD arms, respectively. Pts received a median of 6 cycles with mean relative dose intensities for each drug (%) in older pts of: A+AVD, 92.3, 96.6, 93.3, and 97.9; ABVD, 97.3, 88.7, 93.3, and 95.9. With median follow-up of ~25 months, 2-yr mPFS per IRF was similar in both arms for older ITT pts (A+AVD 70.3% [95% CI: 58.4, 79.4] vs ABVD 71.4% [95% CI: 60.5, 79.8] ; HR=1.00 [95% CI: 0.58, 1.72]; p=0.993). An exploratory analysis of standard PFS per investigator (INV) showed HR=0.85 ([95% CI: 0.49, 1.48] ; p=0.576) (Table 1). For older pts with stage IV cHL (A+AVD n=51; ABVD n=67), there was an increase in 2-yr PFS per INV with A+AVD vs ABVD (74.0% [95% CI: 59.5, 84.0] vs 59.9% [95% CI: 45.6, 71.5] ; HR, 0.66 [95% CI: 0.34, 1.26]; p=0.20); mPFS per IRF improvement with A+AVD in older stage IV pts was lower (HR=0.80; [95% CI: 0.42, 1.53] ). In younger stage III/IV pts ( 〈 60 yrs) 2-yr mPFS per IRF and PFS per INV were also higher compared with older pts in both arms (Table 1). 66 of 83 older A+AVD pts required ≥1 dose modification of brentuximab vedotin, reasons were: dose reduction (n=27), dose held (n=4), dose delayed (n=51), brentuximab vedotin discontinued (n=17). In older pts, grade (G) 3/4 AEs occurred in 88% of A+AVD pts vs 80% ABVD pts; for younger pts, rates were 82% (A+AVD) vs 63% (ABVD) (Table 2). In older pts there were 3 (4%) on-study deaths in the A+AVD arm (1 each: hemophagocytosis, neutropenic sepsis, and myocardial infarction) and 5 (5%) with ABVD (all pulmonary-related). In pts 〈 60 yrs, there were 6 on-study deaths (1%) with A+AVD vs 8 (1%) with ABVD. G3 neutropenia in older pts was (70%) A+AVD pts vs (59%) ABVD pts, and febrile neutropenia (FN) in 31 (37%) vs 17 (17%) pts. In older pts who had G-CSF primary prophylaxis (PP) neutropenia was seen in 4/10 (40%) A+AVD pts vs 1/9 (11%) ABVD pts (on-study FN in 3 [30%] vs 2 [22%] pts). In older pts, treatment-emergent peripheral neuropathy (PN) was reported in 54 (65%) of A+AVD pts vs 42 (43%) of ABVD pts (G≥3 in 15 [18%] vs 3 [3%] pts), respectively. In pts 〈 60 yrs PN was reported in 388 (67%) A+AVD pts vs 244 (43%) ABVD pts (G≥3 in 55 [9%] vs 8 [1%] pts), respectively. In older pts at last follow-up, 65% (35/54) of A+AVD pts and 60% (25/42) of ABVD pts had complete resolution (A+AVD, 39%; ABVD, 38%) or improvement (A+AVD, 26%; ABVD, 21%) of PN events. 2% older A+AVD pts had pulmonary AEs (both G1/2 pulmonary infiltration) vs 13% older ABVD pts. Conclusions For older ECHELON-1 pts, mPFS and PFS were similar in both arms. In the larger subgroup of younger pts, mPFS and PFS were improved vs older pts. As expected, incidence of treatment-emergent AEs was higher in older pts, with regimen-specific AEs seen, including fatal pulmonary events in ABVD pts. The high incidence of FN in older A+AVD pts points to the need for G-CSF PP. Disclosures Evens: Acerta: Consultancy; Pharmacyclics International DMC: Membership on an entity's Board of Directors or advisory committees; Seattle Genetics, Inc.: Membership on an entity's Board of Directors or advisory committees, Research Funding; Affimed: Consultancy; Janssen: Consultancy; Abbvie: Consultancy; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees; Bayer: Consultancy; Tesaro: Research Funding; Novartis: Consultancy. Connors:Merck: Research Funding; Amgen: Research Funding; Takeda: Research Funding; Roche Canada: Research Funding; NanoString Technologies: Patents & Royalties: Named Inventor on a patent licensed to NanoString Technologies, Research Funding; Seattle Genetics: Honoraria, Research Funding; Janssen: Research Funding; F Hoffmann-La Roche: Research Funding; Bayer Healthcare: Research Funding; Cephalon: Research Funding; Bristol Myers-Squibb: Research Funding; Lilly: Research Funding; Genentech: Research Funding. Younes:Sanofi: Honoraria; Merck: Honoraria; Astra Zeneca: Research Funding; Celgene: Honoraria; Incyte: Honoraria; Seattle Genetics: Honoraria; Bayer: Honoraria; Novartis: Research Funding; Curis: Research Funding; J & J: Research Funding; Genentech: Research Funding; Takeda: Honoraria; Roche: Honoraria, Research Funding; Abbvie: Honoraria; Janssen: Honoraria, Research Funding; Pharmacyclics: Research Funding; BMS: Honoraria, Research Funding. Ansell:Merck & Co: Research Funding; LAM Therapeutics: Research Funding; Trillium: Research Funding; Affimed: Research Funding; Seattle Genetics: Research Funding; Regeneron: Research Funding; Takeda: Research Funding; Pfizer: Research Funding; Celldex: Research Funding; Bristol-Myers Squibb: Research Funding. Radford:Takeda: Consultancy, Research Funding, Speakers Bureau; GlaxoSmithKline: Equity Ownership; AstraZeneca: Equity Ownership; Seattle Genetics: Consultancy, Speakers Bureau; ADC Therapeutics: Consultancy, Research Funding; Novartis: Consultancy, Speakers Bureau; Pfizer: Research Funding; Celgene: Research Funding; BMS: Consultancy, Speakers Bureau. Feldman:Seattle Genetics: Research Funding, Speakers Bureau; Janssen: Speakers Bureau; Pharmacyclics: Speakers Bureau; Johnson and Johnson: Speakers Bureau; Celgene: Speakers Bureau; Portola: Research Funding; KITE: Speakers Bureau. Tuscano:Takeda: Research Funding; Genentech: Consultancy, Research Funding; Amgen: Honoraria, Speakers Bureau; Seattle Genetics: Honoraria, Speakers Bureau; Celgene: Honoraria, Research Funding, Speakers Bureau; Pharmacyclics: Research Funding. Oki:Seattle Genetics: Research Funding; Takeda Millenium: Honoraria, Research Funding; Jazz Pharmaceuticals: Employment. Grigg:Roche: Membership on an entity's Board of Directors or advisory committees; Gilead: Membership on an entity's Board of Directors or advisory committees; BMS: Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees. Pocock:Kent & Canterbury Hospital: Employment. Dlugosz-Danecka:Roche: Consultancy; Servier: Consultancy. Fenton:Seattle Genetics, Inc.: Employment, Equity Ownership. Engley:Seattle Genetics: Employment. Liu:Millennium Pharmaceuticals Inc., a wholly owned subsidiary of Takeda Pharmaceutical Company Limited: Employment. Miao:Millennium Pharmaceuticals Inc., a wholly owned subsidiary of Takeda Pharmaceutical Company Limited: Employment. Jolin:Takeda Pharmaceuticals International Co.: Employment. Gautam:Millennium Pharmaceuticals, Inc., Cambridge, MA, USA, a wholly owned subsidiary of Takeda Pharmaceutical Company Limited: Employment. Gallamini:Takeda: Consultancy, Speakers Bureau.

Abstract: Background DHL are high-grade B-cell lymphomas (BCL) characterized by dual gene rearrangements (RA) of MYC and either BCL2 or BCL6. Outcomes are typically dismal, particularly when treated with R-CHOP, as compared to those observed in patients (pts) with similar histologies without dual RA. Few reports have evaluated the use of intensive induction regimens, with or without consolidative stem cell transplantation (SCT). We sought to evaluate the role of intensive induction as well as SCT, and to investigate predictors of outcome in DHL. Methods This study was an IRB-approved retrospective analysis across 15 centers. Cases were diagnosed between 2000-2012 as aggressive BCL harboring RA, by FISH, of MYC along with RA of BCL2 and/or BCL6. Pts were treated with either R-CHOP, or one of the following intensified regimens: R-HyperCVAD, R-EPOCH, R-CODOX-M/IVAC, R-ICE. Survival was estimated using Kaplan Meier method, and comparisons made with log rank test. Multivariable analysis (MVA) was performed using the Cox proportional hazard regression. Results One hundred six pts were analyzed. Median age at diagnosis was 60; 59% were male. The majority had DHL characterized by RA of MYC and BCL2 (77%); the remainder showed RA of MYC and BCL6 (10%), or all three (12%). History of indolent lymphoma was present in 29 pts (27%). The most common histology was DLBCL in 56 pts (53%), followed by BCL unclassifiable (BCLU) in 45 (42%), and Burkitt-like in 5 (5%). Thirty six pts (33%) received R-CHOP, 33 (31%) R-EPOCH, and 28 (36%) R-Hyper-CVAD or CODOX-M/IVAC. Fourteen pts (13%) were consolidated with SCT (n=1 allo and n=13 auto SCT); all were treated with intensive induction. Three additional pts underwent SCT in partial remission or progressive disease following R-CHOP induction. The median PFS and OS for the entire cohort were 8.8 mo and 12 mo, respectively (Table 1); of the 24 pts (23%) alive and without progression, median follow-up was 19 mo. R-EPOCH was superior in achieving complete response (CR) compared with R-CHOP (P 0.01), and trended towards significance compared with pts receiving other intensive induction (P 0.07). Additionally, primary refractory disease, observed in 37 pts (34.5%), occurred less frequently in pts receiving R-EPOCH compared to R-CHOP (P .005) or other intensive regimens (P 0.03); induction regimen did not impact OS in patients not receiving SCT (P 0.7; Fig 1). SCT in first remission was associated with improved OS (P 0.02), and PFS (P 0.006) compared with induction alone. However, among pts achieving CR, SCT was not associated with improved OS compared with observation (P 0.22; Fig 2). Pts with prior history of indolent NHL did not fare worse than those with de novo DHL (P 0.5). No difference in OS was observed based on histology (P 0.2). The following factors were evaluated in MVA: prior indolent lymphoma, histological subtype, IPI 〉 /=3, primary refractory disease, type of induction (R-CHOP vs intensified), and consolidative SCT. Only primary refractory disease (P 〈 0.0001) predicted for inferior OS. Consolidative SCT did not improve OS on MVA (P 0.13). Conclusions In this analysis of DHL, primary refractory disease was the primary predictor of OS. Pts achieving CR did not appear to benefit from consolidative SCT, though our analysis was limited by the fact that pts receiving SCT are often highly selected (for chemosensitivity, age, comorbidities) and in this study, by the low number of pts receiving SCT. R-EPOCH was associated with a decreased rate of primary refractory disease compared to other regimens, and increased rate of CR compared to R-CHOP, but the lack of clear survival benefit suggests that relapsed disease offsets early benefit. Our analysis confirms the generally poor outcomes for pts with DHL, though a subset with chemosensitive disease has an improved prognosis, likely due to favorable disease biology. Further investigation on the role of SCT and of novel agents is needed for this high-risk population. ^Three patients untreated, one received multiple regimens Disclosures: Off Label Use: Brentuximab Vedotin is approved for relapsed, refractory Hodgkin Lymphoma in patients who have already had a transplant or are ineligible for one, or for patients with relapsed, refractory anaplastic large cell lymphoma. Patients treated on clinical trials or off label will be included in this presentation. Petrich:Genetech: Consultancy, Honoraria. Fenske:Seattle Genetics : Consultancy, Honoraria. Smith:Seattle Genetics, Inc.: Research Funding; Spectrum: Consultancy; Cephalon: Consultancy, Speakers Bureau; Celgene: Consultancy, Speakers Bureau; GlaxoSmith Kline: Speakers Bureau. Evens:Seattle Genetics: Consultancy, Honoraria; Millennium: Consultancy, Honoraria, Research Funding; Ziopharm, Inc: Research Funding; Celgene: Consultancy, Honoraria.

Abstract: Abstract 1618 Introduction: Primary breast lymphoma is a rare type of non-Hodgkin lymphoma (NHL), representing about 1% of breast tumors and 2% of extranodal NHL. Diffuse large B-cell lymphoma (DLBCL) is the most common primary subtype presenting in the breast. Due to the low incidence of primary breast DLBCL, outcome data is limited. The aim of this study was to retrospectively assess the natural history of primary breast DLBCL in the pre and post rituximab eras, with specific emphasis on the incidence of local, systemic and central nervous system (CNS) relapses. Methods: Data was retrospectively collected on patients with primary breast DLBCL from seven USA academic medical centers. Institutional review board approval was obtained at each participating site. Patients were identified through institutional databases and tumor registries at each site. Charts were reviewed to obtain demographic and clinical variables including treatment history and dates of relapse and death when applicable. Only patients with stage I/II disease (involvement of breast and localized lymph nodes) were included. All histologies apart from primary DLBCL were excluded. Overall survival (OS) was calculated from the diagnosis date to the date of death or last follow-up. Time to Progression (TTP) was calculated from diagnosis data until the date of pathological evidence of recurrence or death. Data were summarized using descriptive statistics, and survival was analyzed using the Kaplan-Meier method. Results: Between 1984 and 2012, 75 patients were identified who met the eligibility criteria. The median age was 62 years (range 17–87); 81% presented with a palpable mass; 12% had their disease detected incidentally by mammography; 4% presented with B-symptoms; 59% had right breast involvement; 67% had stage I and 33% had stage II disease. The stage-adjusted international prognostic index (IPI) score was 0 in 28% of patients, 1 in 41%, 2, in 25%, 3 in 4% and 4 in 1%. 91% of patients were treated with chemotherapy; 31% of these were treated in the pre-rituximab era and 69% received rituximab. Radiation therapy (RT) was utilized in 68% of patients and was the only treatment modality in 8% of those receiving RT. 8% of patients received CNS prophylaxis with intrathecal chemotherapy. After a median follow-up of 4.5 years (range 0.6 – 20.6 years), the Kaplan-Meier estimated median TTP was 10.4 years (95% CI 6.2 – 14.6 years) and the median OS was 14.6 years (95% CI 6.5 – 22.6 years). The 5-year TTP and 5-year OS were 65% (95% CI 53–77%) and 75% (95% CI 64–86%) respectively. Among the patients who relapsed, 67% occurred within the first 2 years. A total of 7 relapses in the breast were observed, none in patients treated with combination of chemotherapy and RT. In univariate analysis, rituximab exposure was not associated with any difference in TTP or OS. The stage-adjusted IPI was associated with OS; the 5-year OS was 88% (95% CI 79–98%) in patients with a score of 0–1 versus 48% (95% CI 25–71%) in those with a score of 2–4 (log rank p 〈 0.001). The very limited-disease group with a stage-adjusted IPI of 0 had a 5-year OS of 94% (95% CI 83–100%) compared to all others who had a 5-year OS of 67% (95% CI 52–81%; log rank p = 0.001). There was no difference in TTP and OS in patients with solitary versus multiple breast masses or between patients with tumors less than versus more than 7cm. Patients receiving RT in addition to chemotherapy had a longer TTP than those who did not (log rank p = 0.03), but RT was not associated with an improved OS. Patients who relapsed and underwent stem cell transplant (SCT) had similar OS to those who never relapsed. Ten patients (13%) had CNS relapse (3 with leptomeningeal disease, 5 with brain parenchymal disease and 2 with both). All CNS relapses occurred within the first 2.8 years from the time of diagnosis. There was no difference in the rate of CNS relapse in the patients who received IT prophylaxis versus those who did not. Conclusions: In this multicenter study, the largest published to date, primary breast DLBCL appears to have a worse prognosis than early-stage DLBCL in nodal or other extranodal sites. RT was associated with improved TTP. Patients who relapsed were successfully salvaged with SCT, and had similar survival times to those who never relapsed. A high CNS relapse rate (∼1 in 8 patients, including parenchymal disease in 70%) was observed. The small numbers preclude definitive conclusions on the value of intrathecal prophylaxis or the utility of rituximab. Disclosures: No relevant conflicts of interest to declare.

Abstract: Primary breast diffuse large B ‐cell lymphoma ( DLBCL ) is a rare subtype of non‐ H odgkin lymphoma ( NHL ) with limited data on pathology and outcome. A multicentre retrospective study was undertaken to determine prognostic factors and the incidence of central nervous system ( CNS ) relapses. Data was retrospectively collected on patients from 8 US academic centres. Only patients with stage I / II disease (involvement of breast and localized lymph nodes) were included. Histologies apart from primary DLBCL were excluded. Between 1992 and 2012, 76 patients met the eligibility criteria. Most patients (86%) received chemotherapy, and 69% received immunochemotherapy with rituximab; 65% received radiation therapy and 9% received prophylactic CNS chemotherapy. After a median follow‐up of 4·5 years (range 0·6–20·6 years), the K aplan– M eier estimated median progression‐free survival was 10·4 years (95% confidence interval [ CI ] 5·8–14·9 years), and the median overall survival was 14·6 years (95% CI 10·2–19 years). Twelve patients (16%) had CNS relapse. A low stage‐modified I nternational P rognostic I ndex ( IPI ) was associated with longer overall survival. Rituximab use was not associated with a survival advantage. Primary breast DLBCL has a high rate of CNS relapse. The stage‐modified IPI score is associated with survival.

Abstract: We sought to improve upon frontline bendamustine/rituximab (BR) induction therapy followed by rituximab maintenance in untreated high-risk follicular lymphoma (FL). Patients and Methods: Patients were randomized to BR induction followed by 2-year rituximab maintenance (BR-R), BR with bortezomib and rituximab maintenance (BVR-R), or BR followed by lenalidomide (1 year) with rituximab maintenance (BR-LR). Dual primary objectives were complete remission (CR) rate and 1-year disease-free survival (DFS); 289 patients enrolled (NCT01216683). Results: For induction, 92%, 87%, and 86% of patients randomized to BR-R, BVR-R, or BR-LR received six cycles, respectively. CR rate with BR versus BVR induction was 62% versus 75%, respectively (P = 0.04). One-year DFS rates with BR-R versus BR-LR were 85% versus 67%, respectively (P = 0.0009). This was due to an imbalance in CR rates post-BR induction and discontinuation due to adverse events (AEs). The most common grade 3–4 AEs for BVR versus BR were neutropenia and sensory neuropathy (12% vs & lt;1%); 83% of the latter occurred with intravenous bortezomib. The most common grade 3–4 AEs related to LR versus rituximab maintenance were neutropenia 66% versus 21%, respectively (P & lt; 0.0001), and febrile neutropenia 10% versus 2%, respectively (P = 0.05). The overall treatment-related mortality was 1.4%. With 5-year median follow-up, 3-year PFS rates for BR-R, BVR-R, and BR-LR were 77%, 82%, and 76%, respectively (P = 0.36) with OS rates of 87%, 90%, and 84%, respectively (P = 0.79). For prognostication, CR rate and POD-24 were associated with survival. Conclusions: Altogether, neither bortezomib added to BR induction nor lenalidomide added to rituximab maintenance immediately post-BR induction is recommended in untreated FL.

Abstract: Background: Bortezomib has efficacy in follicular lymphoma (FL). Though generally well tolerated, it is associated with a few known toxicities, including neurotoxicity. As a chronically administered agent, it is important to investigate the tolerability of bortezomib over time as a single agent and in combination with chemotherapy. The current method of summarizing adverse events (AEs) -focusing on the maximum grade and reporting only grade 3 or higher incidences- fails to capture toxicity that evolves over time or chronic low grade AEs that may occur at significant expense to patients' quality of life. In this study, we applied the Toxicity over Time (ToxT) analytic approach (Thanarajasingam et al, Lancet Oncol 2016), which graphically and analytically depicts AEs longitudinally, to a randomized Phase 2 ECOG-ACRIN sponsored study, E2408, to characterize chronic toxicity of bortezomib (V) when added to standard bendamustine-rituximab (BR) induction in previously untreated high risk FL. Methods: In E2408, patients (pts) were randomized to one of 3 arms at a 1:2:2 ratio: A) BR x 6 followed by maintenance rituximab (MR) x 2 years (yrs) vs B) BVR x 6 (bortezomib 1.3 mg/m2 IV/SQ days 1, 4, 8, 11) then MR x 2 yrs vs C) BR x 6 then MR x 2 yrs + lenalidomide 20mg/day x 1 yr. Pts enrolled 1/2011-5/2015. This analysis focuses on the 6 cycles of induction only, with arms A and C combined. Six AEs of interests were selected, 4 symptomatic (subjective) AEs (peripheral sensory neuropathy (PSN), diarrhea, febrile neutropenia, fatigue); and 2 non-symptomatic (objective) AEs (neutropenia and thrombocytopenia). Treatment-related post baseline AEs of any grade were investigated by conventional maximum grade toxicity analysis (ToxC) and ToxT methods. The mean AE grades over cycles were analyzed by repeated measures models, time to grade 2 or higher (gr2+)AE were analyzed with time-to-event analysis; and AE profile over the entire course of the study was summarized by area under the curve (AUC) analyses. Comparisons were performed between treatment arms (BVR vs. BR). Results: All 280 randomized treated pts (187 on BR, 93 on BVR) were included in the analysis regardless of eligibility status; 87% (163/187 BR, 81/93 BVR) completed all 6 cycles. Analyzing the symptomatic AEs,ToxC indicates that the overall incidence of grade 3+ PSN was significantly higher in BVR (12%) than BR (1%) (p 〈 .0001). Additional, ToxT captures the trajectory, demonstrating a rapid, rising incidence and worsening grade of PSN on BVR vs BR over 6 cycles in a steam plot of mean gr. by cycle (Fig 1a) and bar chart of incidence and grade per cycle (c1: 13% gr1 3% gr2, c6: 36% gr1 12% gr2 6% gr3 on BVR; c1: 3% gr1, c6: 10% gr1 1% gr2 on BR, Fig. 1b). Risk of developing gr2+ PSN was significantly higher in BVR than BR with 28% vs 0.5% by day 100 (HR=0.01, p 〈 .0001, Fig. 1c). ToxC captures a higher incidence of grade 3+ diarrhea on BVR (7% vs. 1% , p=.01) while AUC from ToxT includes chronic lower grade diarrhea, that is substantial over time on BVR vs. BR (p 〈 .0001), but is not cumulative. Furthermore, the risk of developing gr2+ diarrhea affecting drug tolerability is significantly higher on BVR than BR(13% vs 5% by day 100) (HR=0.3, p=.05). Febrile neutropenia appeared to be similar, and fatigue was marginally more severe under BVR (p=.06 by AUC). For objective AEs, ToxC reveals no significant difference in neutropenia or thrombocytopenia BVR vs BR (neutropenia gr 3+: 36% vs 31%, p=.4; thrombocytopenia gr3+: 10% vs. 5%, p=.12). However, ToxT illustrates that neutropenia is cumulative, worsening over repeated exposure to drug (c1: 2% gr1 5% gr2 5% gr 3+ , c6: 7% gr1 10% gr2 12% gr3+ both arms combined; p 〈 .0001) on mean grade over time (Fig. 2a). In contrast, thrombocytopenia does not worsen with continued treatment (Fig 2b, p=.73). Conclusions: Compared with conventional toxicity analysis (ToxC), ToxT delineated important additional and clinically relevant depictions of both symptomatic and laboratory AEs over time for bortezomib added to BR in FL pts. In patients receiving BVR, close monitoring is suggested for PSN, diarrhea and neutropenia for reassessment of risks and benefits, symptom interventions and dose modification. Longitudinal toxicity analyses such as ToxT can guide AE interventions as well as patient and clinician education, and provide a more patient-centered toxicity assessment of chronically administered therapies for lymphoma. Disclosures Hong: Merck: Consultancy. Evens:Seattle Genetics, Inc.: Membership on an entity's Board of Directors or advisory committees, Research Funding; Acerta: Consultancy; Abbvie: Consultancy; Bayer: Consultancy; Janssen: Consultancy; Novartis: Consultancy; Tesaro: Research Funding; Affimed: Consultancy; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees; Pharmacyclics International DMC: Membership on an entity's Board of Directors or advisory committees. Advani:Kura: Research Funding; Roche/Genentech: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: Participated in an advisory board, Research Funding; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Bristol Myers Squibb: Membership on an entity's Board of Directors or advisory committees, Other: Participated in an advisory board, Research Funding; Celgene: Research Funding; Pharmacyclics: Membership on an entity's Board of Directors or advisory committees, Research Funding; Kyowa: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: Participated in an advisory board; Bayer: Membership on an entity's Board of Directors or advisory committees, Other: Participated in an advisory board; Cell Medica: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: Participated in an advisory board; Infinity: Research Funding; Gilead/Kite: Membership on an entity's Board of Directors or advisory committees, Other: Participated in an advisory board; Janssen: Research Funding; Astra Zeneca: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: Participated in an advisory board; Regeneron: Research Funding; Seattle Genetics: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: Participated in an advisory board, Research Funding; Forty Seven Inc.: Research Funding; Merck: Research Funding; Millenium: Research Funding; Agensys: Research Funding; Celgene: Research Funding; Autolus: Membership on an entity's Board of Directors or advisory committees, Other: Participated in an advisory board. Gascoyne:NanoString: Patents & Royalties: Named Inventor on a patent licensed to NanoString Technologies. Witzig:Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. Dueck:Bayer: Employment; Pfizer: Honoraria; Phytogine: Employment. Kahl:Genentech: Consultancy; Acerta: Consultancy; ADC Therapeutics: Consultancy; Seattle Genetics: Consultancy; Abbvie: Consultancy; Juno: Consultancy; Gilead: Consultancy; Celgene: Consultancy; CTI: Consultancy; AstraZeneca: Consultancy.

Abstract: Background: There remains a critical need to identify untreated HR FL patients (pts) who are at increased risk of early progression and death with conventional treatment. Data examining baseline PET has been reported to be prognostic in FL, however, there remains a paucity of data analyzing this in the context of bendamustine/rituximab (BR) induction followed by maintenance rituximab (MR). We examined the prognostic impact of baseline PET metabolic imaging from the randomized BIONIC study for pts with untreated HR FL. Methods: The BIONIC study conducted by the ECOG-ACRIN Cancer Research Group enrolled untreated grade I/II or IIIa FL pts with HR disease defined as GELF high tumor burden and/or FLIPI score of 3-5. Pts were randomized to: a) standard BR induction x 6 followed by maintenance rituximab (MR) q 2 months x 2 years vs b) bortezomib + BR x 6 followed by MR q 2 months x 2 years vs c) BR x 6 followed by q 2 months MR x 2 years + lenalidomide given concurrently with the first year of MR. Survival analyses showed no significant differences in 4-year progression-free survival (PFS) or overall survival (OS) for any study arm (Evens AM et al, ASH 2017). All pts were thus pooled for the purpose of analyzing baseline PET imaging and other characteristics and for correlation with clinical outcomes. Kruskal-Wallis & Wilcoxon Rank Sum test were used to assess differences in distribution of: metabolic measurements (SUVmax and SUVmean of the dominant mass (i.e., the mass/lesion with the highest SUV uptake); metabolic tumor volume (MTV); and total lesion glycolysis (TLG) by categorical variables); induction treatment response; and end-of-induction (EOI) PET response vis-à-vis Deauville scoring (1-3 = negative). Cox proportional hazards regression was used to correlate these metabolic measurements with PFS & OS and multivariable analyses were conducted. An optimal cutoff threshold (grouping into 'High' or 'Low' categories) was used for the metabolic measurements that were significantly associated with PFS & OS. Results: Metabolic data were received and measurements were analyzed centrally on 182 (71%) of 257 eligible pts. The EOI overall response rate (ORR) for all pts on study was 92% with a complete remission (CR) rate of 73%. Additionally, 12% of pts experienced early progression of disease (POD) within 2 years. SUVmax was borderline for association with PFS (P=0.06) and MTV and TLG were not associated with PFS or OS. We demonstrated a statistically significant linear relationship between continuous SUVmean score with PFS and OS, and thereafter, used the minimum p-vlaue approach to determine the optimal cutoff threshold of 7.03 to group pts into 'High' and 'Low' risk groups; with this threshold, baseline SUVmean of the dominant mass was categorized as high risk in 27% pts. The 4-year PFS rates for SUVmean low vs high groups were 80% (95% CI 72, 90%) vs 55% (40, 74%), respectively, P 〈 0.001; and the corresponding 4-year OS rates were 93% (89, 98)% vs 80% (95% CI 69, 93%), respectively, P=0.01 (see Fig. 1). Sensitivity analyses showed no differences in baseline SUVmean by study arm, GELF or FLIPI. The only clinical characteristic that varied among patients with low vs high baseline SUVmean was Black race (0.8 vs 8.0%, respectively, Chi-square P=0.08); there were no other differences based on age, sex, stage, FLIPI, GELF status, ECOG PS, LDH, or # of extranodal sites. In addition, baseline SUVmean correlated with EOI PET (negative EOI PET with baseline SUVmean Low vs High: 81% vs 62%, respectively, P=0.03). In multivariable analyses, both baseline SUVmean and EOI PET remained significant (SUVmean: PFS HR 2.62 (95% CI 1.40-4.92), P=0.001, OS HR 2.37 (95% CI 1.01-5.56), P=0.02; EOI PET PFS HR 4.70 (95% CI 2.74-9.54), P 〈 0.001, OS HR 2.78 (95% CI 1.18-6.56), P=0.01). Finally, baseline SUVmean was also strongly predictive of FL pts who experienced early 2-year POD (Chi-square P 〈 0.001). Conclusions: High baseline SUVmean of the dominant mass was a strong independent prognostic factor for survival for untreated HR FL pts treated with BR-based induction with rituximab maintenance and significance was independent of FLIP or GELF criteria. Collectively, this represents a novel and simple method to identify FL pts at increased risk of early POD and poor survival with standard therapy. Continued investigation of combined PET imaging analyses and other correlative studies to enrich prognostication are warranted. Disclosures Hong: Merck: Consultancy. Advani:Bristol Myers Squibb: Other: Consultancy/Advisory role and Institutional Research Support; Kyowa: Other: Consulting/Advisory Role; Infinity: Other: Institutional Research Support; Pharmacyclics: Other: Institutional Research Support; Seattle Genetics: Other: Consultancy/Advisory role, Institutional Research Support; Regeneron Pharmaceuticals, Inc.: Other: Institutional Research Support; Millenium: Other: Institutional Research Support; Bayer Healthcare Pharmaceuticals: Other: Consultancy/Advisory Role; Autolus: Other: Consultancy/Advisory Role; Takeda: Other: Consultancy/Advisory Role; Celgene: Other: Institutional Research Support; Roche/Genentech: Other: Consultancy/Advisory Role, Institutional Research Support; AstraZeneca: Other: Consultancy/Advisory Role; Cell Medica: Other: Consultancy/Advisory Role; Gilead/Kite: Other: Consultancy/Advisory Role; Agensys: Other: Institutional Research Support; Kura: Other: Institutional Research Support; Forty Seven, Inc: Other: Institutional Research Support; Merck: Other: Institutional Research Support; Janssen Pharmaceutical: Other: Institutional Research Support. Gascoyne:NanoString: Patents & Royalties: Named Inventor on a patent licensed to NanoString Technologies. Witzig:Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. Kahl:Acerta: Consultancy; Celgene: Consultancy; Abbvie: Consultancy; Juno: Consultancy; CTI: Consultancy; Gilead: Consultancy; Seattle Genetics: Consultancy; Genentech: Consultancy; AstraZeneca: Consultancy; ADC Therapeutics: Consultancy. Evens:Affimed: Consultancy; Novartis: Consultancy; Acerta: Consultancy; Bayer: Consultancy; Tesaro: Research Funding; Pharmacyclics International DMC: Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees; Seattle Genetics, Inc.: Membership on an entity's Board of Directors or advisory committees, Research Funding; Abbvie: Consultancy.

Abstract: Introduction ALK-negative anaplastic large cell lymphoma (ALK- ALCL) is an uncommon type of T-cell non-Hodgkin lymphoma (T-NHL) with worse prognosis compared to ALK-positive (ALK+) ALCLs. Most published studies on the genomics of T-NHL have focused on peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS), and previous studies of ALCL described rearrangements in DUSP22 and TP63 and mutations in genes comprising the JAK/STAT pathway as common genetic drivers in ALK- ALCL. The degree to which these drivers affect survival or other molecular features of ALK- ALCL remains unknown. Here, we describe novel subgroups of ALK- ALCL that exhibit distinct survival. One subgroup appears molecularly similar to ALK+ALCLs and is associated with favorable survival while the second subgroup is quite distinct from ALK- ALCLs and associated with poor outcomes. Methods and Results Eighty-two ALK- ALCL patients were recruited to the Atlas of Blood Cancer (ABC) genomes project, a worldwide consortium established to define the molecular origins of blood cancers. Tumor biopsies from these patients, as well as 10 ALK+ ALCL samples for comparison were obtained from participating institutions. Each case was subjected to centralized pathology review by an experienced panel of hematopathologists to ensure the accuracy of the diagnosis. All cases, along with paired normal tissues, were subjected to DNA and RNA (whole exome-level) sequencing on the Illumina platform to identify mutations and expression changes for each of these cases using methods well established in our group and described previously. We first examined the genetic alterations in ALK- ALCLs. In addition to frequently described genetic alterations such as TP63 and DUSP22 rearrangements, as well as mutations in JAK1, STAT3 and TP53, we also detected mutations in ERBB4, SETD2 and KMT2D, which may serve as potential novel drivers and have not been described previously to our knowledge. We next performed comparative gene expression analysis of the ALK- and ALK+ ALCLs. Surprisingly, a proportion of ALK- ALCL cases (38%) clustered together with ALK+ ALCLs and had a signature resembling ALK+ cases, which we designated as "ALK-like ALCL" here. Both the ALK-like ALCLs and the other ALK- ALCL cases showed decreased ALK expression compared to the ALK+ ALCLs by gene expression analysis. These results point to downstream pathways that are common among ALK+ALCLs and ALK-like ALCLs, but different from the other ALK- ALCLs. Gene set enrichment analysis revealed that the ALK-like ALCLs overexpressed genes in pathways related to monocyte and fibroblast activation, whereas the remaining ALK- ALCLs overexpressed genes in the T follicular helper cells, memory T cells and adaptive immune response-related pathways (P & lt;0.001 in all cases). Kaplan-Meier survival analysis revealed that patients with ALK-like ALCL had significantly better overall survival compared to the other cases (P=0.01, Wald test). Conclusion Our data indicate that ALK- ALCLs represent a heterogeneous group of diseases and comprise at least two distinct subgroups that can be identified based on their similarity to the ALK+ ALCLs. The ALK-like ALCLs demonstrated distinct molecular features and favorable outcomes. Our results provide a potentially new approach to patient risk-stratification and pathological classification of this disease. Disclosures Kwong: Celgene: Consultancy, Honoraria, Research Funding; Bayer: Consultancy, Honoraria, Research Funding; Astellas: Consultancy, Honoraria, Research Funding; Amgen: Consultancy, Honoraria, Research Funding; Bristol Myers Squibb: Consultancy, Honoraria, Research Funding; BeiGene: Consultancy, Honoraria, Research Funding; Gilead: Consultancy, Honoraria, Research Funding; Janssen: Consultancy, Honoraria, Research Funding; Merck: Consultancy, Honoraria, Research Funding; Novartis: Consultancy, Honoraria, Research Funding; Roche: Consultancy, Honoraria, Research Funding; Takeda: Consultancy, Honoraria, Research Funding. Jaye: Stemline Therapeutics: Honoraria. Behdad: Roche/Foundation Medicine: Speakers Bureau; Thermo Fisher: Speakers Bureau; Lilly: Speakers Bureau. Hsi: AbbVie Inc, Eli Lilly: Research Funding. Dave: Data Driven Bioscience: Current equity holder in publicly-traded company.