Kolibaba, Kathryn S.

Abstract Background: Patients with relapsed indolent NHL (iNHL) have limited standard treatment options. Lenalidomide combined with rituximab (R 2) has shown complimentary clinical activity and is a tolerable regimen in both untreated and relapsed or refractory (R/R) patients with iNHL (RELEVANCE : N Engl J Med 2018;379:934 and AUGMENT: J Clin Oncol. 2019;37:1188). Methods: MAGNIFY is a multicenter, phase 3b trial in patients with R/R follicular lymphoma (FL) grades 1-3b, transformed FL (tFL), marginal zone lymphoma (MZL), or mantle cell lymphoma (MCL; NCT01996865) exploring optimal lenalidomide duration. In the induction phase, lenalidomide 20 mg PO on days 1-21 of a 28-day cycle + rituximab IV at 375 mg/m 2/week cycle 1 and then every 8 weeks starting with cycle 3 (R 2) are administered for 12 cycles. Patients with stable disease, partial response, or complete response/complete response unconfirmed (CR/CRu) were randomized 1:1 to R 2 vs rituximab maintenance for 18 months. Data presented here are the complete analysis from the induction phase in efficacy-evaluable patients with FL grades 1-3a or MZL (FL grade 3b, tFL, and MCL not included). The focus of this interim analysis was overall response rate (ORR) by 1999 IWG criteria in the induction intention-to-treat population. Results: As of March 5, 2021, 394 patients (318 [81%] FL gr1-3a; 76 [19%] MZL) were enrolled. The median follow-up was 40.6 mo (range, 0.6-79.6). Median age was 66 y (range, 35-91), 328 (83%) had stage III/IV disease, with a median of 2 prior therapies (94% prior rituximab-containing). ORR was 71% (n = 279) with 42% (n = 164) CR/CRu (Table). All patients have completed R 2 induction (n = 232, 59%) or discontinued study treatment (n = 162, 41%). 141 patients (36%) prematurely discontinued both lenalidomide and rituximab, primarily due to adverse events (AEs) (n = 54, 14%) or progressive disease (n = 42, 11%). The majority of patients who have completed induction have been randomized and entered maintenance (n = 217). Median duration of response in the induction period was not reached (95% CI, 43.9 mo-NR), and median progression-free survival in the induction safety population (n = 393) was 50.5 mo (95% CI, 39.5-NR). Efficacy results are reported in the table by histology subgroups (FL vs MZL), and rituximab-refractory, double-refractory, and early relapse statuses. Most common all-grade AEs were 47% fatigue, 43% neutropenia, 37% diarrhea, 30% nausea, and 30% constipation. Grade 3/4 AEs occurring in ≥ 5% of patients included 37% neutropenia (10 patients [3%] had febrile neutropenia), 8% leukopenia, 6% thrombocytopenia, 5% anemia, and 5% fatigue. Conclusions: These data represent complete analysis of all patients in the induction phase of MAGNIFY which continue to support that R 2 is active with a tolerable safety profile in patients with R/R FL grade 1-3a and MZL, including rituximab-refractory, double-refractory, and early relapse patients. Figure 1 Figure 1. Disclosures Lansigan: Celgene/BMS: Consultancy, Membership on an entity's Board of Directors or advisory committees. Andorsky: Abbvie: Consultancy, Research Funding; Celgene/BMS: Consultancy, Research Funding; Epizyme: Research Funding. Coleman: immunomedics: Current equity holder in publicly-traded company, Current holder of individual stocks in a privately-held company, Current holder of stock options in a privately-held company; Abbvie: Research Funding; Bristol Myers: Research Funding; Celgene: Research Funding; Genentech: Research Funding; Gilead: Research Funding; BeiGene: Research Funding; Innocare: Research Funding; Merck: Research Funding; Pfizer: Research Funding; Roche: Research Funding. Yacoub: Dynavex: Current equity holder in publicly-traded company; Cara: Current equity holder in publicly-traded company; Ardelyx: Current equity holder in publicly-traded company; Agios: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; ACCELERON PHARMA: Membership on an entity's Board of Directors or advisory committees; CTI Biopharma: Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Incyte: Consultancy, Honoraria, Speakers Bureau; Seattle Genetics: Honoraria, Speakers Bureau; Hylapharm: Current equity holder in publicly-traded company. Melear: TG Therapeutics: Speakers Bureau; Astrazeneca: Speakers Bureau; Janssen: Speakers Bureau. Fanning: Sanofi: Speakers Bureau; Genmab: Membership on an entity's Board of Directors or advisory committees; TG Pharma: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Genentech: Membership on an entity's Board of Directors or advisory committees; Takeda: Speakers Bureau; ADC Therapeutics: Membership on an entity's Board of Directors or advisory committees; BMS: Speakers Bureau. Kolibaba: TG Therapeutics: Current Employment, Current holder of individual stocks in a privately-held company, Current holder of stock options in a privately-held company; Atara Biotechm: Consultancy; McKesson Specialty Health: Consultancy; Sunitomo Dainippon Pharma: Consultancy; Tolero Pharma: Consultancy, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company). Nowakowski: Incyte: Consultancy; Kymera Therapeutics: Consultancy; TG Therapeutics: Consultancy; Blueprint Medicines: Consultancy; Nanostrings: Research Funding; Curis: Consultancy; Selvita: Consultancy; Zai Labolatory: Consultancy; Daiichi Sankyo: Consultancy; Bantham Pharmaceutical: Consultancy; Karyopharm Therapeutics: Consultancy; Ryvu Therapeutics: Consultancy; Genentech: Consultancy, Research Funding; Kyte Pharma: Consultancy; Roche: Consultancy, Research Funding; Celgene/Bristol Myers Squibb: Consultancy, Research Funding; MorphoSys: Consultancy. Gharibo: BMS: Current Employment, Current equity holder in publicly-traded company, Current holder of individual stocks in a privately-held company, Current holder of stock options in a privately-held company. Ahn: Bristol Myers Squibb: Current Employment, Current equity holder in publicly-traded company; ADC therapeutics: Current equity holder in publicly-traded company. Li: BMS: Current Employment, Current equity holder in publicly-traded company, Current holder of individual stocks in a privately-held company, Current holder of stock options in a privately-held company, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company), Research Funding. Sharman: BeiGene: Consultancy; TG Therapeutics: Consultancy; Lilly: Consultancy; Centessa: Current holder of stock options in a privately-held company, Membership on an entity's Board of Directors or advisory committees; Pharmacyclics LLC, an AbbVie Company: Consultancy; AstraZeneca: Consultancy; BMS: Consultancy; AbbVie: Consultancy.

Background: Lenalidomide combined with rituximab (R2) has shown complimentary clinical activity and is a tolerable regimen in both untreated and relapsed or refractory (R/R) patients with indolent non-Hodgkin lymphoma. Patients with advanced age at diagnosis are considered to be high risk, supporting post-hoc subgroup analyses by age, with a focus on patients aged ≥ 70 years from the MAGNIFY study. Methods: MAGNIFY is a multicenter, phase IIIb trial in patients with R/R follicular lymphoma (FL) grades 1-3b, transformed FL (tFL), marginal zone lymphoma (MZL), or mantle cell lymphoma (MCL; NCT01996865) exploring optimal lenalidomide duration. Lenalidomide 20 mg on days 1-21 of a 28-day cycle + rituximab 375 mg/m2/week cycle 1 and then every 8 weeks starting with cycle 3 (R2) are administered for 12 cycles followed by 1:1 randomization in patients with stable disease, partial response, or complete response/complete response unconfirmed (CR/CRu) to R2 vs rituximab maintenance for 18 months. Data presented here focus on induction R2 in efficacy-evaluable FL grade 1-3a and MZL patients (FL grade 3b, tFL, and MCL not included) receiving ≥ 1 treatment with baseline/postbaseline assessments. The primary end point is progression-free survival (PFS) by 1999 International Working Group criteria. Post-hoc analyses were performed by analyzing data from patients aged ≥ 70 years at time of study entry. Results: As of November 30, 2019, 393 patients have enrolled and 152 (39%) were aged ≥ 70 years. Baseline characteristics including histology, disease status, and prior treatments of patients ≥ 70 and the overall population are shown in the table. Median PFS in the ≥ 70 subgroup was 36.0 months (95% CI, 28.3-NR). Overall response rate and CR/CRu were 75% and 38%, with a median duration of response that was not reached (95% CI, 27.1-NR). Efficacy results for the overall population are shown in the table. In patients ≥ 70 the most common (≥ 20%) any-grade treatment emergent adverse events (TEAEs) were fatigue (44%), neutropenia (41%), diarrhea (34%), constipation (34%), and nausea (27%). Neutropenia (35%) was the only grade 3/4 TEAE occurring in > 10% of patients (febrile neutropenia occurred in 3 patients [2%]). TEAEs led to lenalidomide dose reduction in 69 patients (46%) and discontinuation in 40 patients (26%). Seventy-eight patients ≥ 70 (51%) completed all 12 cycles of induction treatment, and 72 (47%) have entered the maintenance phase. Sixty-one patients ≥ 70 (40%), compared to 35% of patients in overall population, prematurely discontinued both lenalidomide and rituximab, due to TEAEs (n = 26; 17%), progressive disease (n = 15; 10%), patient withdrawal (n = 12; 8%), death (n = 5; 3%), and other reasons (n = 3; 2%). Neutropenia was the only TEAE leading to discontinuation of lenalidomide in more than 2 patients (n = 10; 7%). Conclusions: Similar to findings in the overall population, R2 treatment in advanced-age patients with R/R FL and MZL resulted in encouraging efficacy, and with close attention to dose reduction there is a tolerable safety profile. Table Disclosures Lansigan: BMS Steering Committee for MAGNIFY Program: Membership on an entity's Board of Directors or advisory committees; Spectrum Pharma: Consultancy, Research Funding; BMS: Consultancy; Seattle Genetics: Consultancy. Andorsky:AstraZeneca: Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; CTI: Research Funding. Coleman:Novartis Pharmaceuticals: Research Funding; Merck Sharp & Dohme Corp.: Research Funding; Boston BIoMedical, Inc.: Research Funding; BeiGene: Research Funding; Acerta: Research Funding; Innocare: Research Funding; ARCUS Biosciences: Research Funding; AstraZeneca Pharmaceuticals, LP (Acerta Pharma BV Trials): Research Funding; AstraZeneca Pharmaceuticals, LP: Research Funding; BMS (Celgene Corporation): Research Funding; Eli Lilly and Company: Research Funding; EMD Serono Research and Development Institute Inc.: Research Funding; Genetech (F. Hoffman-LaRoche Ltd): Research Funding; Hutchinson MediPharma, LTD: Research Funding; Incyte Corporation: Research Funding; Ipsen Group: Research Funding; Karyopharma Therapeutics, Inc.: Research Funding; Klus Pharma, Inc.: Research Funding; MeiPharma, Inc.: Research Funding; Seattle Genetics: Research Funding. Yacoub:Novartis: Honoraria, Speakers Bureau; Agios: Speakers Bureau; Incyte: Speakers Bureau; Hylapharm: Current equity holder in private company; Cara therapeutics: Current equity holder in publicly-traded company; Ardelyx: Current equity holder in publicly-traded company; Dynavax: Current equity holder in publicly-traded company. Melear:AstraZeneca: Speakers Bureau; Janssen: Speakers Bureau. Fanning:Prisma Health: Current Employment; Abbvie: Consultancy; TG Therapeautics: Consultancy; Bristol Myers Squibb: Consultancy, Speakers Bureau; Takeda: Consultancy, Speakers Bureau; Sanofi Aventis: Speakers Bureau. Kolibaba:Compass Oncology: Ended employment in the past 24 months; Atara Biotech: Consultancy; TG Therapeutics: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Sumitomo Dainippon Pharma Oncology: Consultancy, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company; AbbVie: Research Funding; Acerta: Research Funding; Celgene: Research Funding; Genentech: Research Funding; Gilead: Research Funding; Pharmacyclics: Research Funding; Seattle Genetics: Research Funding; Verastem: Honoraria; Janssen: Research Funding; Novartix: Research Funding. Reynolds:IHA Hematology/Oncology Consultants: Current Employment. Nowakowski:Ryvu: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other; Nanostrings: Research Funding; Seattle Genetics: Consultancy; Curis: Consultancy; MorphoSys: Consultancy, Research Funding; Roche: Consultancy, Research Funding; Kymera: Consultancy; Denovo: Consultancy; Kite: Consultancy; Celgene/BMS: Consultancy, Research Funding. Gharibo:Bayer: Ended employment in the past 24 months; Bristol Myers Squibb: Current Employment, Current equity holder in publicly-traded company. Ahn:BMS: Current Employment, Current equity holder in publicly-traded company. Li:BMS: Current Employment, Current equity holder in publicly-traded company. Rummel:Celgene: Consultancy, Honoraria; Janssen: Honoraria; Amgen GmbH: Honoraria; Roche: Honoraria; Novartis Pharma GmbH: Honoraria. Sharman:Bristol Meyers Squibb: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Roche: Consultancy, Research Funding; Acerta: Consultancy, Research Funding; TG Therapeutics: Consultancy, Research Funding; BeiGene: Research Funding; Genentech: Consultancy, Research Funding; AbbVie: Consultancy, Research Funding; Pfizer: Consultancy, Research Funding; Pharmacyclics: Consultancy, Research Funding; AstraZeneca: Consultancy, Research Funding.

Background: Relapse is expected when treating patients with follicular lymphoma (FL) and marginal zone lymphoma (MZL), with a shortened response associated with each relapse. Lenalidomide combined with rituximab (R2) has shown enhanced activity, with a recently reported median progression free-survival (PFS) of 39.4 months in patients with relapsed/refractory (R/R) indolent non-Hodgkin lymphoma, including those with FL and MZL (AUGMENT; J Clin Oncol. 2019;37:1188). Methods: MAGNIFY is a multicenter, phase IIIb trial in patients with R/R FL grades 1-3b, transformed FL (tFL), MZL, or mantle cell lymphoma (MCL; NCT01996865) in which optimal lenalidomide duration is being explored. Patients received 12 cycles of R2 (lenalidomide 20 mg/d, d1-21/28 + rituximab 375 mg/m2 weekly in cycle 1 and then on day 1 of cycles 3, 5, 7, 9, and 11) followed by 1:1 randomization in patients with stable disease, partial response, or complete response/complete response unconfirmed (CR/CRu) to R2 versus rituximab maintenance for 18 months. Data presented here focus on induction R2 in efficacy-evaluable MZL patients compared with the overall population of FL grades 1-3a+MZL (not including FL grade 3b, tFL, or MCL) receiving ≥ 1 treatment with baseline/post-baseline assessments. The primary end point is progression-free survival (PFS) by 1999 International Working Group criteria. Results: As of November 30, 2019, 393 patients with FL grades 1-3a and MZL enrolled; 76 (19%) had MZL. The median age of MZL patients was 68 years (range, 46-90), 68 (89%) had stage III/IV disease, and 72 (95%) had prior rituximab-containing therapy. Overall response rate was 68% with 39% CR/CRu, and median duration of response was 38.6 months (95% CI, 29.4-not reached [NR]). The median PFS was 41.2 months (95% CI, 38.4-NR). Efficacy results for MZL subtypes and the overall population (FL grades 1-3a + MZL) are shown in the table. Forty-two patients (55%) have completed 12 cycles of R2, and 41 (54%) have been randomized and entered maintenance. Twenty-eight patients (37%) prematurely discontinued both lenalidomide and rituximab, primarily due to adverse events (AEs; n = 11; 14%) and progressive disease (n = 6; 8%). The most common (≥ 20%) all-grade AEs were neutropenia (49%), diarrhea (37%), anemia (25%), thrombocytopenia (24%), and constipation (24%). Most common (≥ 10%) grade 3/4 AEs were neutropenia (41%; 1 patient [1%] had febrile neutropenia), thrombocytopenia (13%), and leukopenia (11%). Conclusions: R2 is active with a tolerable safety profile in patients with R/R MZL. The efficacy and safety profile of R2 in MZL patients were similar to results observed in the overall MAGNIFY population. Disclosures Coleman: Seattle Genetics: Research Funding; EMD Serono Research and Development Institute Inc.: Research Funding; Innocare: Research Funding; ARCUS Biosciences: Research Funding; AstraZeneca Pharmaceuticals, LP (Acerta Pharma BV Trials): Research Funding; AstraZeneca Pharmaceuticals, LP: Research Funding; BMS (Celgene Corporation): Research Funding; Eli Lilly and Company: Research Funding; Genetech (F. Hoffman-LaRoche Ltd): Research Funding; Hutchinson MediPharma, LTD: Research Funding; Ipsen Group: Research Funding; Karyopharma Therapeutics, Inc.: Research Funding; Klus Pharma, Inc.: Research Funding; MeiPharma, Inc.: Research Funding; Merck Sharp & Dohme Corp.: Research Funding; Novartis Pharmaceuticals: Research Funding; Incyte Corporation: Research Funding; Boston BIoMedical, Inc.: Research Funding; BeiGene: Research Funding; Acerta: Research Funding. Andorsky:CTI: Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; AstraZeneca: Research Funding. Yacoub:Roche: Other: Support of parent study and funding of editorial support; Dynavax: Current equity holder in publicly-traded company; Ardelyx: Current equity holder in publicly-traded company; Incyte: Speakers Bureau; Hylapharm: Current equity holder in private company; Cara Therapeutics: Current equity holder in publicly-traded company; Agios: Honoraria, Speakers Bureau; Novartis: Speakers Bureau. Melear:Janssen: Speakers Bureau; AstraZeneca: Speakers Bureau. Fanning:Takeda: Consultancy, Speakers Bureau; Bristol Myers Squibb: Consultancy, Speakers Bureau; TG Therapeautics: Consultancy; Abbvie: Consultancy; Prisma Health: Current Employment; Sanofi Aventis: Speakers Bureau. Kolibaba:Atara Biotech: Consultancy; Compass Oncology: Ended employment in the past 24 months; Verastem: Honoraria; Seattle Genetics: Research Funding; Pharmacyclics: Research Funding; Novartix: Research Funding; Janssen: Research Funding; Gilead: Research Funding; Genentech: Research Funding; Celgene: Research Funding; Acerta: Research Funding; AbbVie: Research Funding; Sumitomo Dainippon Pharma Oncology: Consultancy, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company; TG Therapeutics: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. Lansigan:BMS: Consultancy; Seattle Genetics: Consultancy; BMS Steering Committee for MAGNIFY Program: Membership on an entity's Board of Directors or advisory committees; Spectrum Pharma: Consultancy, Research Funding. Reynolds:IHA Hematology/Oncology Consultants: Current Employment. Nowakowski:Kymera: Consultancy; Ryvu: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other; Curis: Consultancy; Kite: Consultancy; MorphoSys: Consultancy, Research Funding; Denovo: Consultancy; Seattle Genetics: Consultancy; Nanostrings: Research Funding; Celgene/BMS: Consultancy, Research Funding; Roche: Consultancy, Research Funding. Gharibo:Bristol Myers Squibb: Current Employment, Current equity holder in publicly-traded company; Bayer: Ended employment in the past 24 months. Ahn:BMS: Current Employment, Current equity holder in publicly-traded company. Li:BMS: Current Employment, Current equity holder in publicly-traded company. Rummel:Roche: Honoraria; Amgen GmbH: Honoraria; Celgene: Consultancy, Honoraria; Janssen: Honoraria; Novartis Pharma GmbH: Honoraria. Sharman:BeiGene: Research Funding; Bristol Meyers Squibb: Consultancy, Research Funding; Pfizer: Consultancy, Research Funding; Pharmacyclics: Consultancy, Research Funding; AstraZeneca: Consultancy, Research Funding; Genentech: Consultancy, Research Funding; AbbVie: Consultancy, Research Funding; TG Therapeutics: Consultancy, Research Funding; Acerta: Consultancy, Research Funding; Roche: Consultancy, Research Funding; Celgene: Consultancy, Research Funding.

8046 Background: Patients (pts) with relapsed iNHL have limited standard treatment options. The immunomodulatory agent lenalidomide shows enhanced activity with rituximab (ie, R2), which recently reported 39.4-mo median PFS in R/R iNHL pts (AUGMENT; J Clin Oncol. 2019;37:1188). Methods: MAGNIFY is a multicenter, phase IIIb trial in pts with R/R FL gr1-3a, MZL, or MCL (NCT01996865) exploring optimal lenalidomide duration. Lenalidomide 20 mg/d, d1-21/28 + rituximab 375 mg/m2/wk c1 and then q8wk c3+ (R2) are given for 12c followed by 1:1 randomization in pts with SD, PR, or CR to R2 vs rituximab maintenance for 18 mo. Data presented here focus on induction R2 in efficacy-evaluable FL and MZL pts (MCL not included) receiving ≥ 1 treatment with baseline/post-baseline assessments to analyze the primary end point of ORR by 1999 IWG criteria. Results: As of June 16, 2019, 393 pts (81% FL gr1-3a; 19% MZL) were enrolled with a median follow up of 23.7 mo (range, 0.6-57.8) for censored pts (n = 335). Median age was 66 y (range, 35-91), 83% had stage III/IV disease, with a median of 2 prior therapies (95% prior rituximab-containing). ORR was 69% with 40% CR/CRu (Table). Median DOR was 39.0 mo, and median PFS was 40.1 mo. 199 pts (51%) have completed 12c of R2, and 188 (48%) have been randomized and entered maintenance. 139 pts (35%) prematurely discontinued both lenalidomide and rituximab, primarily due to AEs (n = 52, 13%) or PD (n = 45, 11%). Most common all-grade AEs were 48% fatigue, 43% neutropenia, 36% diarrhea, 31% nausea, and 30% constipation. Grade 3/4 AE neutropenia was 36% (9 pts [2%] had febrile neutropenia); all other grade 3/4 AEs occurred in < 7% of pts. Conclusions: R2 is active with a tolerable safety profile in pts with R/R FL and MZL, including rituximab-refractory, double-refractory, and early relapse pts. Clinical trial information: NCT01996865 . [Table: see text]

7519 Background: Acalabrutinib, a highly selective, potent, covalent Bruton tyrosine kinase (BTK) inhibitor, has a 24% overall response rate (ORR) as a single agent in R/R DLBCL. Pem targets PD-1, an immune checkpoint that limits anticancer responses. Pem showed responses in patients (pts) with Richter transformation who failed ibrutinib and can augment acalabrutinib activity in vitro. This study assessed acalabrutinib + Pem in R/R DLBCL. Methods: Pts with DLBCL, ≥1 prior chemoimmunotherapy and no prior allogeneic transplant received acalabrutinib 100 mg PO BID until progressive disease (PD) + Pem 200 mg/kg IV Q3W up to 2 y. Germinal center B-cell (GCB) vs non-GCB subtype was assessed by immunohistochemistry. Primary endpoint was safety. Results: Sixty-one pts (30 GCB; 31 non-GCB) were accrued, with a median age (range) of 67 y (30-85) and a median of 3 (1-8) prior therapies; 1 pt had prior autologous transplant. The most common Gr 3/4 adverse events (AEs) were neutropenia (15%) and anemia (11%). Gr 5 AEs were respiratory failure (n=3), sepsis, septic shock and abdominal abscess (n=1 each). All Gr atrial fibrillation was 5% (n=3), and major hemorrhage (≥ Gr 3) was 11% (4 gastrointestinal, 1 pulmonary, 1 epistaxis, 1 hematuria). Gr 3/4 immune-mediated events were elevated alanine aminotransferase (n=4), pneumonitis (n=2) and colitis (n=1). The ORR was 26% (Table) and was similar in GCB (27%) and non-GCB (26%) tumors. The median time on study was 5.2 mo (0.4-30.4+). Acalabrutinib/Pem discontinuations were due to PD (62%/56%) and AEs (15%/26%). As of June 2018, 10 pts remain on study; 6 on active therapy and 7 without PD. Conclusions: Acalabrutinib + Pem was well tolerated, with meaningful activity and some exceptional responders (>24 mo) in these R/R DLBCL pts. Randomized trials of the combination vs single agent are needed. Clinical trial information: NCT02362035. [Table: see text]

Abstract Introduction DLBCL is the most common lymphoid neoplasm in adults (Swerdlow 2016). While durable CRs are achieved in approximately 70% of patients (pts) with frontline RCHOP therapy (Pfreundschuh 2008), pts with high-risk features often experience disease resistance or relapse. In Part 1 of an ongoing study, pts with high-intermediate or high risk DLBCL by international prognostic index (IPI) scores, regardless of CD30 expression by IHC, were treated with 1.2 or 1.8 mg/kg brentuximab vedotin (BV) combined with RCHOP. After 3 of the first 10 pts treated at 1.8 mg/kg BV+RCHOP developed Grade 3 peripheral neuropathy (per Standardized MedDRA Query [SMQ]), all pts enrolled subsequently received treatment with 1.2 mg/kg BV+RCHOP. Following completion of enrollment in Part 1, the protocol was amended to enroll a non-randomized portion of the study (Part 2) evaluating the safety and efficacy of 1.8 mg/kg BV+RCHP (Yasenchak 2015), followed by an open-label, randomized portion comparing BV+RCHP to RCHOP (Part 3). Initial results from Part 2 and updated results from Part 1 are reported here. Methods For Part 2 of the study, pts with CD30-expressing high-intermediate and high-risk DLBCL were treated with up to 6 cycles of 1.8 mg/kg BV+RCHP (NCT01925612). Key inclusion criteria were CD30 expression by IHC performed by a local pathology lab and standard IPI scores of 3-5 or age-adjusted IPI (aaIPI) scores of 2-3 (high-intermediate/high risk). CD30 expression was confirmed by a central pathology lab, although CD30 expression by local pathology lab was required for eligibility. Disease response was evaluated with PET/CT per Cheson 2007. Results At the time of analysis for this ongoing study, 11 pts in Part 2 were treated with BV+RCHP (7 male, 4 female; 22-78 yrs). Of these pts, 9 had high-intermediate risk (IPI 3, aaIPI 2) and 2 had high risk disease (IPI 4-5, aaIPI 3), 6 had Stage IV disease, and 6 had an ECOG score of 2. At the end of treatment, the overall response rate was 91% (9 CR, 1 PR); 1 pt had PD after Cycle 4. The most frequent (>20%) treatment-emergent adverse events (AEs) were alopecia and nausea (73% each); fatigue (64%); constipation and peripheral sensory neuropathy (55% each); neutropenia and throat irritation (36% each); and chills, diarrhea, headache, and stomatitis (27% each). Grade 3 or 4 AEs occurred in 8 pts and 5 pts had serious AEs, which included febrile neutropenia, bacteremia, nausea, pneumocystis jiroveci pneumonia, pulmonary embolism, and vomiting. Peripheral sensory neuropathy occurred in 6 pts and all were Grade 1 or 2 events; no peripheral motor neuropathy AEs were reported. No AEs were fatal or led to discontinuation. One pt discontinued treatment after Cycle 4 due to disease progression. For the first 51 pts in Part 1, the progression-free survival (PFS) at 18 months for pts with CD30 expression (25 pts) or without detectable CD30 expression (24 pts) by IHC was 79% (95% CI: 57%, 91%) versus 58% (95% CI: 36%, 75%), respectively. Overall survival for pts was 92% (95% CI: 71%, 98%) versus 71% (95% CI: 48%, 85%), respectively. Ten pts had pre-existing peripheral neuropathy (per SMQ) at study entry. Treatment-emergent peripheral neuropathy (per SMQ) was observed in 75% of pts (38/51) who received BV+RCHOP; 55% of these pts (21/38) had resolution of all or some peripheral neuropathy events. Conclusions 1.8 mg/kg BV+RCHP is active as frontline treatment in CD30-expressing, high-intermediate/high risk DLBCL. When combined with RCHP, 1.8 mg/kg BV appears to be well-tolerated. The PFS and OS for pts with CD30-expression who received BV+RCHOP appear promising. The study is currently ongoing in pts with CD30-expressing high-intermediate/high risk DLBCL to assess the safety and activity of 1.8 mg/kg BV+RCHP versus standard RCHOP. Disclosures Halwani: Bristol Myers-Squibb: Research Funding; Kyowa Hakko Kirin: Research Funding; Takeda: Research Funding; Genentech: Research Funding; AbbVie: Consultancy, Other: Travel Expenses, Research Funding; Seattle Genetics: Consultancy, Research Funding; Immune Design: Research Funding; Miragen: Research Funding; Pharmacyclics: Consultancy; Amgen: Research Funding. Yasenchak:Seattle Genetics: Research Funding. Farber:Seattle Genetics: Research Funding. Burke:Pfizer: Consultancy; Janssen: Consultancy; Incyte: Consultancy; TG Therapeutics: Other: Travel Expenses; Millenium: Consultancy. Fayad:Seattle Genetics: Consultancy, Research Funding. Holkova:Seattle Genetics: Research Funding. Knapp:Insys Therapeutics, Inc.: Consultancy, Other: Travel, Accommodations, Expenses; Pharmacyclics, LLC, an AbbVie Company: Consultancy, Other: Travel, Accommodations, Expenses, Research Funding. Kolibaba:Gilead: Consultancy, Research Funding; Celgene: Research Funding; TG Therapeutics: Research Funding; Takeda Pharmaceuticals International Co.: Research Funding; Seattle Genetics: Research Funding; Pharmacyclics: Research Funding; janssen: Research Funding; GSK: Research Funding; Genentech: Research Funding; Acerta: Research Funding. Patel-Donnelly:Seattle Genetics: Research Funding. Yimer:Ariad Pharmaceuticals: Consultancy; Biotheranostics: Consultancy; Bluebird Bio: Equity Ownership; Kite Pharma: Equity Ownership; Clovis Oncology: Equity Ownership; Juno Therpeutics: Equity Ownership; Seattle Genetics: Research Funding. Smith:Celgene: Consultancy, Speakers Bureau; Seattle Genetics: Research Funding. Levy:Janssen: Speakers Bureau; Amgen: Speakers Bureau; Takeda Pharmaceuticals International Co.: Speakers Bureau; Seattle Genetics: Research Funding; Actinium Pharmaceuticals, Inc.: Research Funding. Seetharam:Seattle Genetics: Research Funding. Belada:Seattle Genetics: Research Funding. Brooks:Seattle Genetics: Research Funding. Kingsley:Gilead: Equity Ownership; Pharmacyclics LLC, an AbbVie Company: Equity Ownership. Wagner-Johnston:Seattle Genetics: Research Funding. Ruffner:Forma Therapeutics: Consultancy; Sydnax: Consultancy; Seattle Genetics: Employment, Equity Ownership; Array Biopharma: Employment; Medivation: Employment. Bartlett:Gilead: Consultancy.

Abstract Introduction RCHOP is the standard frontline treatment for patients with DLBCL. However, for patients with high-intermediate or high-risk disease (IPI 3-5), outcomes are suboptimal, with an estimated 3-year PFS of about 55%. In addition to IPI, an additional factor associated with an increased risk include non-GCB cell of origin. Brentuximab vedotin, an ADC targeting CD30, has demonstrated single-agent activity in relapsed/refractory DLBCL patients. Of note, higher ORR and CR, as well as longer duration of PFS, were observed in those patients with CD30 detected on tumor cells by routine IHC. Methods This phase 2 study was designed to evaluate combination therapy using brentuximab vedotin (BV) and standard RCHOP chemotherapy as frontline treatment in patients with high-intermediate/high risk (standard IPI score 3-5 or age-adjusted IPI [aaIPI] score 2-3) DLBCL, regardless of CD30 expression (ClinicalTrials.gov NCT01925612). Patients were randomized to receive either 1.2 mg/kg BV+RCHOP or 1.8 mg/kg BV+RCHOP for up to 6 cycles of treatment. BV was given on Day 1 of every 21-day cycle. Response was assessed per investigator using Cheson 2007. AEs, physical examination findings, and laboratory testing were utilized to characterize safety. Tumor cell CD30 expression was measured by IHC and gene expression analysis; soluble CD30 was measured in plasma. Tumor microenvironment was also evaluated for frequency of immune-infiltrating cells. The primary endpoints for this study were the tolerability of each regimen and the CR rate at the end of treatment (EOT). Key secondary endpoints included progression-free survival (PFS). Additional exploratory endpoints included CD30 expression on tumor specimens (CD30- defined as <1% per IHC) and correlation of CD30 expression and response. Results Twenty-nine patients were treated with 1.2 mg/kg BV+RCHOP and 22 patients were treated with 1.8 mg/kg BV+RCHOP. Over half (63%) were high-intermediate risk (IPI 3, aaIPI 2) and 37% were high risk (IPI 4-5, aaIPI 3). Most had Stage IV disease (71%) and 27% had an ECOG score of 2. AEs in ≥50% of patients included peripheral sensory neuropathy (63%), fatigue (61%), nausea (55%), and diarrhea (53%). Grade 3 or higher events occurred in 76% of patients; the most frequent were neutropenia (33%) and febrile neutropenia (31%). The PET-negative CR rate was 69% overall; CD30+ patients had a CR rate of 76% (19/25) compared with 63% (12/19) in CD30- patients by IHC. Although PFS data are still immature (median follow up of 8 months), the estimated PFS rate at 12 months was 82% (95% CI: 58, 93) in CD30+ patients and 56% (95% CI: 32, 75) in CD30- patients. 60% (3/5) of patients with CD30- ABC-DLBCL progressed versus 27% (3/11) of CD30+ ABC-DLBCL patients. Four patients with EBV+ DLBCL were treated and all achieved CR; 3 EBV+ patients remain in remission after a median follow-up of 12 months. Within the microenvironment, a higher percentage of CD3+ T-cells was observed in patients with CR (23%; range, 4-80%) than in those with PR (14%; range, 10-15%) or PD (11%; range, 5-15%). Of the 32 patients who have not yet progressed, 50% had ≥20% CD3+ cells compared to 18% of patients with PD (2/11). Other factors, including soluble CD30 levels and infiltrating CD68+ cells, were not associated with clinical outcomes. Conclusions Interim results demonstrate that adding BV to RCHOP results in a high rate of CR in this population of IPI 3-5 DLBCL. Patients with CD30-expression in the tumor appear to have a higher CR rate and fewer early progression events than patients with CD30- DLBCL. Furthermore, subsets of patients who have a particularly poor prognosis (CD30+ ABC subtype and EBV+ DLBCL) appeared to have a favorable outcome with BV+RCHOP. Evaluation of the tumor microenvironment showed that higher frequencies of infiltrating CD3+ cells were observed in the CR group, suggesting possible immunologic correlates of response. However, CD30 expression appears to have greater prognostic significance in this study despite the relatively small sample size. These results are intriguing and merit further testing in a randomized trial. Disclosures Yasenchak: Seattle Genetics, Inc.: Research Funding. Off Label Use: Brentuximab vedotin is indicated in the US for treatment of patients with Hodgkin lymphoma after failure of autologous stem cell transplant or after failure of at least two prior multi-agent chemotherapy regimens in patients who are not ASCT candidates and for the treatment of patients with systemic anaplastic large cell lymphoma after failure of at least one prior multi-agent chemotherapy regimen. The drug is being evaluated in this study for use as frontline treatment in patients with high-intermediate/high risk DLBCL in combination with multiagent chemotherapy. . Halwani:Abbvie: Research Funding; Pharmacyclics: Other: Travel expenses, Research Funding; Takeda/Millenium: Research Funding; BMS: Research Funding; Seattle Genetics, Inc.: Other: Travel expenses, Research Funding; Roche/Genentech: Research Funding; Kyowa Hakko Kirin: Research Funding; Amgen: Research Funding. Advani:Seattle Genetics, Inc.: Research Funding; Genetech: Consultancy. Ansell:Bristol-Myers Squibb: Research Funding; Celldex: Research Funding. Budde:Merck: Research Funding; Ikara Inc: Patents & Royalties; Atara Biotherapeutics: Consultancy; Seattle Genetics, Inc.: Research Funding. Burke:Millenium/Takeda: Consultancy; Incyte: Consultancy; TG Therapeutics: Other: Travel expenses; Gilead: Consultancy; Janssen: Consultancy; Seattle Genetics, Inc.: Research Funding. Farber:Seattle Genetics, Inc.: Research Funding. Holkova:Seattle Genetics, Inc.: Research Funding. Kolibaba:GSK: Research Funding; Seattle Genetics, Inc.: Research Funding; Acerta: Research Funding; Celgene: Research Funding; Gilead: Consultancy, Research Funding; Takeda Pharmaceuticals International Co.: Research Funding; Genentech: Research Funding; Pharmacyclics: Research Funding; Janssen: Research Funding; TG Therapeutics: Research Funding. Knapp:Celgene: Research Funding; Heron Pharmaceuticals: Other: Travel expenses, Research Funding; Merck: Research Funding; Seattle Genetics, Inc.: Research Funding; Takeda Pharmaceuticals International Co.: Research Funding; Brystol-Myers Squibb: Research Funding; Genentech: Honoraria, Other: Travel expenses, Research Funding; Pharmacyclics LLC, an AbbVie Company: Research Funding; EMD Serono: Research Funding. Li:Seattle Genetics, Inc.: Employment, Equity Ownership. Manley:Seattle Genetics, Inc.: Employment, Equity Ownership. Patel-Donnelly:Seattle Genetics, Inc.: Research Funding. Seetharam:Seattle Genetics, Inc.: Research Funding. Yimer:Seattle Genetics, Inc.: Research Funding. Bartlett:Gilead: Consultancy, Research Funding; Janssen: Research Funding; Pharmacyclics: Research Funding; Genentech: Research Funding; Pfizer: Research Funding; Novartis: Research Funding; Millennium: Research Funding; Colgene: Research Funding; Medimmune: Research Funding; Kite: Research Funding; Insight: Research Funding; Seattle Genetics: Consultancy, Research Funding; MERC: Research Funding; Dynavax: Research Funding; Idera: Research Funding; Portola: Research Funding; Bristol Meyers Squibb: Research Funding; Infinity: Research Funding; LAM Theapeutics: Research Funding.

Abstract Background Outcomes for patients with DLBCL have improved over the past decade, with the addition of rituximab to CHOP or CHOP-like multi-agent chemotherapy regimens improving the 3-year overall survival (OS) of patients by 10-16% compared to multi-agent chemotherapy alone (Coiffier 2002; Pfreundschuh 2010). However, patients with high-intermediate or high-risk disease have relatively poor outcomes with the standard RCHOP regimen (Ziepert 2010); in a recent prospective trial of intermediate- and high-risk DLBCL patients, complete response (CR) rate for RCHOP alone was 26% (Hainsworth 2011). Brentuximab vedotin (ADCETRIS®) is an antibody-drug conjugate comprising the antibody cAC10, specific for human CD30, covalently attached to the microtubule-disrupting agent monomethyl auristatin E (MMAE) via a protease-cleavable linker. Brentuximab vedotin has demonstrated compelling activity as a single agent in patients with relapsed or refractory DLBCL, even those with low CD30 expression (Bartlett 2013). This phase 2, randomized, open label study is designed to evaluate the antitumor activity and safety of brentuximab vedotin (1.2 or 1.8 mg/kg) when administered in combination with standard RCHOP chemotherapy (A+RCHOP) for the front-line treatment of patients with CD30-unselected high-intermediate/high-risk (standard IPI score 3–5 or age-adjusted IPI [aaIPI] score 2–3) DLBCL (ClinicalTrials.gov NCT01925612). Methods Patients were randomized to receive up to 6 cycles of either 1.2 or 1.8 mg/kg brentuximab vedotin administered IV on Day 1 of every 21-day cycle in combination with RCHOP; prednisone was administered orally on Days 1-5 of every 21-day cycle. Assessments included disease response per Cheson 2007, as evaluated by the investigator, surveillance of adverse events (AEs), physical examination findings, and laboratory testing. The primary endpoints for this study are the CR rate at the end of treatment (EOT) and the type, incidence, and severity of AEs. Key secondary endpoints include objective response rate (ORR), progression-free survival (PFS), and OS. Results At the time of the planned interim analysis, 33 patients were enrolled (17 patients, 1.2 mg/kg A+RCHOP; 16 patients, 1.8 mg/kg A+RCHOP). Median age for all patients was 66 years (range, 21 to 81). At baseline, 36% were high-risk (IPI 4-5, aaIPI 3) and 64% were high-intermediate risk (IPI 3, aaIPI 2). The majority of patients (73%) had Stage IV disease and 33% had an ECOG status of 2. At the time of interim analysis, a total of 12 patients (6 patients in each arm) had completed EOT. Across both dose levels, ORR was 92% (11/12), with 7 CRs (58%), 4 PRs (33%), and 1 PD. The patient with PD subsequently died. Patients with PR had a median reduction of baseline tumor size of 84% (range, 92% to 83%), as measured by SPD. The only patient with follow-up after EOT converted from PR to CR without subsequent therapy. Treatment-emergent AEs occurring in ≥30% of patients treated (26/33) were nausea, diarrhea, peripheral sensory neuropathy, fatigue, and decreased appetite. Grade 3 or higher events occurring in more than 2 patients were febrile neutropenia and neutropenia. Events of peripheral neuropathy occurred equally per arm (46%, 1.2 mg/kg A+RCHOP; 46% 1.8 mg/kg A+RCHOP) and were generally Grade 1 or 2 (15% and 23%, respectively); events were of similar grade across dose levels. The median time to onset of any grade of peripheral neuropathy was 6 weeks (range, 2 to 10 weeks). Five patients (19%) had dose reductions due to peripheral neuropathy and 3 patients (12%) had dose reductions due to febrile neutropenia. One patient who received 1.2 mg/kg A+RCHOP discontinued study drug due to an AE (thrombocytopenia). Conclusions At doses of 1.2 or 1.8 mg/kg, A+RCHOP exhibited manageable toxicity in the treatment of newly-diagnosed DLBCL; the incidence of peripheral neuropathy was similar to single-agent administration of brentuximab vedotin (Pro 2012, Younes 2012) and RCHOP alone (Rummel 2013, Flinn 2014). In 12 patients with response-assessable, high-intermediate and high-risk DLBCL, A+RCHOP showed encouraging antitumor activity, with an ORR of 92% and a CR rate of 58%. Disclosures Yasenchak: Seattle Genetics, Inc.: Research Funding. Off Label Use: Brentuximab vedotin is indicated in the US for treatment of patients with Hodgkin lymphoma after failure of autologous stem cell transplant or after failure of at least two prior multi-agent chemotherapy regimens in patients who are not ASCT candidates and for the treatment of patients with systemic anaplastic large cell lymphoma after failure of at least one prior multi-agent chemotherapy regimen. . Farber:Seattle Genetics, Inc.: Research Funding. Budde:Seattle Genetics, Inc.: Research Funding. Ansell:Seattle Genetics, Inc.: Research Funding. Advani:Takeda Pharmaceuticals International Co.: Research Funding; Celgene: Research Funding; Pharmacyclics: Research Funding; Jansseen Pharmaceuticals: Research Funding; Genentech: Research Funding; Seattle Genetics, Inc.: Research Funding, Travel expenses Other. Holkova:Seattle Genetics, Inc.: Research Funding. Halwani:Seattle Genetics, Inc.: Research Funding. Knapp:Takeda Pharmaceuticals International Co.: Research Funding; EMD Serono: Research Funding; Bristol Myers Squibb: Research Funding; Celgene: Research Funding; Merck: Research Funding; Heron Pharmaceuticals: Research Funding, Travel expenses, Travel expenses Other; Genentech: Research Funding, Travel expenses, Travel expenses Other; Seattle Genetics, Inc.: Research Funding; Pharmacyclics: Research Funding. Fayad:Seattle Genetics, Inc.: Consultancy, Research Funding. Kolibaba:Genentech: Research Funding; Takeda Pharmaceuticals International Co.: Research Funding; Seattle Genetics, Inc.: Research Funding. Patel-Donnelly:Seattle Genetics, Inc.: Research Funding. Seetharam:Seattle Genetics, Inc.: Research Funding. Manley:Seattle Genetics, Inc.: Employment, Equity Ownership. Bartlett:Genentech: Research Funding; ImaginAb: Research Funding; Celgene: Research Funding; MedImmune: Research Funding; Novartis: Research Funding; Pharmacyclics: Research Funding; Pfizer: Research Funding; Takeda Pharmaceuticals International Co.: Research Funding; Seattle Genetics, Inc.: Research Funding, Travel expenses Other; Janssen: Research Funding; Astra Zeneca: Research Funding.