Rosenbaum, Cara A.

7520 Background: With goal of simplifying clinical trials in lymphomas, we reported that bone marrow biopsies are irrelevant for response assessment in most patients (pts) with follicular lymphoma (FL) on trials (Rutherford JCO 2023). We then investigated impact of imaging frequency in FL clinical trials. We hypothesized that progression free survival (PFS) would not be different when imaging is performed less frequently than required by trials. Methods: We identified all trials through Alliance for Clinical Trials in Oncology that enrolled untreated pts with FL from 2008-2016. We considered 2 imaging schedules: protocol specified (control) vs relaxed (X) in which response assessments at every other required time point were omitted. For each trial, we estimated PFS using Kaplan Meier methods for the 2 schedules then determined difference in PFS between schedules as % change from control schedule in 2 year (yr) PFS rate. We performed simulation studies to approximate impact of less frequent imaging on PFS estimation using 50901 (low-intermediate risk FL) and 50904 (intermediate-high risk FL, control arm). We assumed exponential distribution for PFS, where rate parameter was calculated based on observed median PFS with uniform censoring distribution. Protocols for 50901 and 50904 mandated imaging every 4 months (mos) for 2 yrs then every 6 mos (S0). We ran 1000 iterations of 100 observations using 3 tumor assessment follow up schedules: every 6 mos for 2 yrs then yearly (S1), every 8 mos for 2 yrs then yearly (S2), or yearly (S3) for simulated progression times. We calculated deviation of PFS using simulated schedules from truth (S0). Results: Across 5 FL trials, median percent change of schedule X from control schedule in estimated 2yr PFS was 2.1% (0.0-30.8%) and in estimated 4yr PFS was 0.9% (-8.6-25.7%). Disparate result in 50901 is due to small shift in events with low number of pts at risk for progression. Simulation study results by trial were: for 50901, true median PFS 1.9 yrs and average median PFS for S1, S2, and S3 of 2.05, 2.11, and 2.21 yrs; for 50904 (control arm), true median PFS 4.1 yrs and average median PFS for S1, S2, and S3 of 4.16, 4.12, and 4.05 yrs. Conclusions: Our findings support decreased frequency of imaging studies in FL clinical trials, which would improve resource use and decrease pt burden. We plan a larger analysis to confirm results. https://acknowledgments.alliancefound.org . Clinical trial information: NCT00553501 , NCT01145495 , NCT01190449 , NCT01286272 , NCT01829568 .[Table: see text]

PURPOSE Bone marrow biopsies (BMB) are performed before/after therapy to confirm complete response (CR) in patients with lymphoma on clinical trials. We sought to establish whether BMB add value in assessing response or predict progression-free survival (PFS) or overall survival (OS) outcomes in follicular lymphoma (FL) subjects in a large, multicenter, multitrial cohort. METHODS Data were pooled from seven trials of 580 subjects with previously untreated FL through Alliance for Clinical Trials in Oncology (Alliance) and SWOG Cancer Research Network (SWOG) completing enrollment from 2008 to 2016. RESULTS Only 5/580 (0.9%) had positive baseline BMB, CR on imaging, and subsequent positive BMB ( P < .0001). Therefore, BMB were irrelevant to response in 99% of subjects. A sensitivity analysis of 385 FL subjects treated on an Eastern Cooperative Oncology Group study was included. In the Eastern Cooperative Oncology Group cohort, 5/385 (1.3%) had BMB that affected response assessment. Since some subjects do not undergo confirmatory BMB, we performed a landmark survival analysis from first radiologic CR with data from 580 subjects from Alliance and SWOG. Of subjects with CR on imaging (n = 187), PFS and OS were not significantly different among those with negative BMB to confirm CR (n = 47) versus those without repeat BMB (n = 140; PFS: adjusted hazard ratio, 1.10, 95% CI, 0.62 to 1.94, log-rank P = .686; OS: hazard ratio, 0.59, 95% CI, 0.23 to 1.53, log-rank P = .276). CONCLUSION We conclude that BMB add little value to response assessment in subjects with FL treated on clinical trials and we recommend eliminating BMB from clinical trial requirements. BMB should also be removed from diagnostic guidelines for FL except in scenarios in which it may change management including confirmation of limited stage and assessment of cytopenias. This would reduce cost, patient discomfort, resource utilization, and potentially remove a barrier to trial enrollment.

Abstract Background: SUMOylation, a post-translational modification analogous to ubiquitination, attaches a small, ubiquitin-like modifier (SUMO) to target proteins. SUMOylation plays a central role in the immune system by regulating type I interferon (IFN-I) expression, thereby functioning to constrain the innate immune response (Decque Nat Immunol 2016), and limit tumor immune surveillance. The SUMOylation pathway is often overexpressed in multiple myeloma (MM) and is associated with poor outcomes (Driscoll Blood 2010). TAK-981 is a first-in-class, small-molecule inhibitor of SUMO-activating enzyme, which blocks the SUMOylation cascade (Langston J Med Chem 2021) and increases IFN-I production and signaling in innate immune cells (Nakamura AACR 2019). In ex vivo assays, TAK-981 activated the IFN-I pathway, increased phagocytic activity of monocyte-derived macrophages, and increased natural killer (NK) cell cytotoxicity via IFN-I signaling (Nakamura AACR 2019). The ability of TAK-981 to promote activation of macrophages and NK cells provides a mechanistic rationale for its use in combination with monoclonal antibodies (mAbs) reliant on antibody-dependent cellular cytotoxicity and phagocytosis; in vivo experiments have demonstrated synergistic activity between TAK-981 and rituximab, and between TAK-981 and the anti-CD38 mAbs daratumumab (dara) (Nakamura SITC 2020) or mezagitamab (meza; TAK-079; Figure 1). Patients with MM who have disease refractory to the three most effective classes of anti-myeloma therapies (proteasome inhibitors [PIs], immunomodulatory drugs [IMiDs], and anti-CD38 mAbs) have a poor prognosis, with median survival 9.2 months (Gandhi Leukemia 2019). Given the incurable nature of advanced MM and the highly complex mechanisms of resistance, continued efforts to better understand MM biology at the time of relapse and to translate this into effective treatment combinations are needed. Combination therapies that engage the immune system to treat MM may offer substantial clinical benefit. Methods: To be eligible for this multicenter, open-label, Phase 1b/2 trial (NCT04776018), patients must have failed at least 3 prior lines of anti-myeloma therapy, have MM disease that is triple-class refractory (defined as refractory/intolerant to ≥1 PI and ≥1 IMiD, and refractory to ≥1 anti-CD38 mAb), and have demonstrated disease progression on their last therapy. Prior CAR-T therapy is allowed. Patients will be assigned to TAK-981 plus subcutaneous (SC) meza (Phase 1 Part 1) or SC dara (dara and hyaluronidase-fihj; Phase 1 Part 2). The primary objectives of Phase 1b are to determine safety and tolerability, and to select the recommended Phase 2 dose (RP2D) and schedule for TAK-981 with each mAb; secondary objectives are to evaluate preliminary antitumor activity, to characterize TAK-981 pharmacokinetics (PK), and to explore pharmacodynamic (PD) markers of TAK-981 target engagement and SUMOylation pathway inhibition. Approximately 30 patients will participate in the Phase 1b Part 1 dose escalation of TAK-981 plus meza (~15 patients per dosing schedule), and ~15 patients will participate in the Phase 1b Part 2 dose escalation of TAK-981 plus SC dara. The primary objective of Phase 2 is to evaluate the efficacy of TAK-981 at the RP2D in combination with an anti-CD38 mAb; ~36 patients will be enrolled. In Phase 1b, patients will receive TAK-981 via a 1-hour intravenous infusion either on days 1, 4, 8, 11, and 15 (twice weekly; BIW) or on days, 1, 8, 15, and 22 (weekly; QW) for 2x 28-day cycles, then 8x every other week, then monthly. Meza 600 mg SC or dara 1800 mg SC will be given 8x weekly, 8x every other week, then monthly, in a 28-day cycle (Figure 2). Treatment will continue until disease progression or unacceptable toxicity (max. 24 cycles). TAK-981 dose escalation will proceed from 60 mg BIW, a dose shown to be pharmacologically active in a first-in-human, single-agent TAK-981 study (TAK-981-1002; data on file). Dose escalation will be guided by Bayesian Optimal Internal Design with Informative Prior (iBOIN) plus consideration of other safety, clinical, PK, and PD data. The iBOIN design selects the true maximum tolerated dose (if any) with high accuracy by allocating more patients to dose levels with a prior dose-limiting toxicity probability closest to the target of 0.3. This study is currently enrolling patients, with the first patient dosed in May 2021. Figure 1 Figure 1. Disclosures Lonial: AMGEN: Consultancy, Honoraria; Takeda: Consultancy, Honoraria, Research Funding; Janssen: Consultancy, Honoraria, Research Funding; GlaxoSmithKline: Consultancy, Honoraria, Research Funding; TG Therapeutics: Membership on an entity's Board of Directors or advisory committees; BMS/Celgene: Consultancy, Honoraria, Research Funding; Merck: Honoraria; Abbvie: Consultancy, Honoraria. Boccia: BMS: Consultancy, Honoraria, Research Funding, Speakers Bureau; Janssen: Consultancy, Honoraria, Speakers Bureau; Abbvie: Consultancy, Honoraria, Speakers Bureau; Takeda: Honoraria, Research Funding, Speakers Bureau; Amgen: Research Funding, Speakers Bureau; Epizyme: Honoraria, Speakers Bureau; Morphosis: Honoraria, Speakers Bureau. Yimer: Beigene: Speakers Bureau; Astrazeneca: Speakers Bureau; Karyopharm: Current equity holder in publicly-traded company, Speakers Bureau; Janssen: Speakers Bureau; GSK: Speakers Bureau; Sanofi: Speakers Bureau; Amgen: Speakers Bureau; Pharmacyclics: Speakers Bureau; Texas Oncology: Current Employment. Levy: Jazz Pharmaceuticals: Consultancy, Honoraria, Speakers Bureau; Morphosys: Consultancy, Honoraria, Other: Promotional speaker, Speakers Bureau; Karyopharm: Consultancy, Honoraria, Other: Promotional speaker, Speakers Bureau; Dova: Consultancy, Other: Promotional speaker; Janssen Pharmaceuticals: Consultancy, Honoraria, Other: Promotional speaker, Speakers Bureau; Amgen Inc.: Consultancy, Honoraria, Other: Promotional speaker, Speakers Bureau; GSK: Consultancy, Other: Promotional speaker; Epizyme: Consultancy, Other: Promotional speaker; Novartis: Consultancy, Other: Promotional speaker; AbbVie: Consultancy, Honoraria, Other: Promotional speaker, Speakers Bureau; Beigene: Consultancy, Honoraria, Speakers Bureau; Bristol Myers Squibb: Consultancy, Honoraria, Other: Promotional speaker, Speakers Bureau; AstraZeneca: Consultancy, Honoraria, Speakers Bureau; Gilead Sciences, Inc.: Consultancy, Honoraria, Speakers Bureau; Seattle Genetics: Consultancy, Honoraria, Other: Promotional speaker, Speakers Bureau; Takeda: Consultancy, Honoraria, Other: Promotional speaker, Speakers Bureau; TG Therapeutics: Consultancy, Honoraria, Speakers Bureau. Abonour: Takeda: Research Funding; GSK: Consultancy, Honoraria, Research Funding; Celgene-BMS: Membership on an entity's Board of Directors or advisory committees, Research Funding; Jensen: Honoraria, Research Funding. Mohan: Medical College of Wisconsin: Current Employment. Girnius: BMS: Honoraria, Speakers Bureau; Celgene: Speakers Bureau; Genentech: Honoraria; GSK: Honoraria, Speakers Bureau; Takeda: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Beigene: Speakers Bureau. Rosenbaum: Takeda: Honoraria; Akcea: Honoraria; Janssen: Honoraria. Nadeem: Karyopharm: Membership on an entity's Board of Directors or advisory committees; BMS: Membership on an entity's Board of Directors or advisory committees; Adaptive Biotechnologies: Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees; GSK: Membership on an entity's Board of Directors or advisory committees. Berg: Takeda: Current Employment, Current equity holder in publicly-traded company, Current holder of stock options in a privately-held company. Chao: Takeda: Current Employment. Berger: Takeda Development Center Americas, Inc.: Current Employment. Nakamura: Takeda Development Center Americas, Inc.: Current Employment. Zhang: Takeda: Current Employment. Song: Takeda Pharmaceuticals International Co.: Current Employment. Ward: Takeda: Current Employment. Proscurshim: Takeda Pharmaceuticals: Current Employment, Current holder of individual stocks in a privately-held company. Kumar: Novartis: Research Funding; Tenebio: Research Funding; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Antengene: Consultancy, Honoraria; Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Roche-Genentech: Consultancy, Research Funding; Astra-Zeneca: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Abbvie: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; BMS: Consultancy, Research Funding; Beigene: Consultancy; Bluebird Bio: Consultancy; KITE: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Merck: Research Funding; Oncopeptides: Consultancy; Amgen: Consultancy, Research Funding; Carsgen: Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Adaptive: Membership on an entity's Board of Directors or advisory committees, Research Funding; Sanofi: Research Funding. OffLabel Disclosure: Study of the investigational agent TAK-981 in combination with daratumumab and hyaluronidase-fihj or the investigational agent mezagitamab (TAK-079).

Abstract Frailty is most prevalent among elderly multiple myeloma (MM) patients, and frail patients have a higher risk of poor outcomes due to reduced performance status or comorbidities. This post hoc analysis assessed efficacy and safety of carfilzomib combinations in frail patients with relapsed and/or refractory MM from the phase 3 ASPIRE (carfilzomib [27 mg/m2]-lenalidomide-dexamethasone [KRd27] vs lenalidomide-dexamethasone [Rd]), ENDEAVOR (carfilzomib [56 mg/m2]-dexamethasone [Kd56] vs bortezomib-dexamethasone [Vd]), and ARROW (once-weekly carfilzomib [70 mg/m2]-dexamethasone [Kd70] vs carfilzomib [27 mg/m2]-dexamethasone [Kd27]) studies. A frailty algorithm incorporating age, Charlson comorbidity index, and performance status classified patients as fit, intermediate, or frail. Results are presented for frail patients (ASPIRE, n = 196; ENDEAVOR, n = 330; ARROW, n = 141). In ASPIRE, median progression-free survival (PFS) (hazard ratio; 95% confidence interval) was 24.1 (KRd27) vs 15.9 months (Rd) (0.78; 0.54-1.12); median overall survival (OS) was 36.4 vs 26.2 months (0.79; 0.57-1.08). In ENDEAVOR, median PFS was 18.7 (Kd56) vs 6.6 months (Vd) (0.50; 0.36-0.68); median OS was 33.6 vs 21.8 months (0.75; 0.56-1.00). In ARROW, median PFS was 10.3 (once-weekly Kd70) vs 6.6 months (twice-weekly Kd27) (0.76; 0.49-1.16). In all 3 studies, rates of grade ≥3 treatment-emergent adverse events were consistent with those observed in the primary studies. The ASPIRE, ENDEAVOR, and ARROW primary analyses demonstrated favorable benefit-risk profiles with carfilzomib-containing regimens compared with controls. Across clinically relevant subgroups, including those by frailty status, consistent efficacy and safety were observed with KRd27, Kd56, and weekly Kd70, and treatment with these regimens should not be restricted by frailty status.

Abstract The primary cause of morbidity and mortality in patients with multiple myeloma (MM) is an infection. Therefore, there is great concern about susceptibility to the outcome of COVID-19–infected patients with MM. This retrospective study describes the baseline characteristics and outcome data of COVID-19 infection in 650 patients with plasma cell disorders, collected by the International Myeloma Society to understand the initial challenges faced by myeloma patients during the COVID-19 pandemic. Analyses were performed for hospitalized MM patients. Among hospitalized patients, the median age was 69 years, and nearly all patients (96%) had MM. Approximately 36% were recently diagnosed (2019-2020), and 54% of patients were receiving first-line therapy. Thirty-three percent of patients have died, with significant geographic variability, ranging from 27% to 57% of hospitalized patients. Univariate analysis identified age, International Staging System stage 3 (ISS3), high-risk disease, renal disease, suboptimal myeloma control (active or progressive disease), and 1 or more comorbidities as risk factors for higher rates of death. Neither history of transplant, including within a year of COVID-19 diagnosis, nor other anti-MM treatments were associated with outcomes. Multivariate analysis found that only age, high-risk MM, renal disease, and suboptimal MM control remained independent predictors of adverse outcome with COVID-19 infection. The management of MM in the era of COVID-19 requires careful consideration of patient- and disease-related factors to decrease the risk of acquiring COVID-19 infection, while not compromising disease control through appropriate MM treatment. This study provides initial data to develop recommendations for the management of MM patients with COVID-19 infection.

Background: Smoldering multiple myeloma (SMM) represents an intermediate stage between monoclonal gammopathy of undetermined significance and active myeloma with a high risk of progression to active MM, especially during the initial years after diagnosis. Available clinical risk factors have enabled development of risk stratification systems that allow for identification of patients at the highest risk of progression, opening opportunities for early intervention. Two phase 3 trials using lenalidomide with dexamethasone or lenalidomide alone have both shown benefit for early intervention by decreasing the risk of progression and improving the overall survival in the former. It remains unknown if an approach using a single active drug to delay progression, or one that uses therapies like active myeloma, represent a better approach; both are being studied in phase 3 trials. We designed this phase 2 trial to examine if an intense but limited duration therapy can possibly provide a significant elimination of the tumour burden that can potentially lead to long term responses. Patients and Methods: Patients with SMM (per updated IMWG definition of SMM) with high risk disease (defined by the IMWG updated risk stratification criteria- presence of any two of the following: Serum M spike &gt; 2 gm/dL OR an involved to uninvolved FLC ratio &gt; 20 OR bone marrow PC% &gt; 20%) or a score of ≥9 using the risk scoring system using FLC ratio, serum M spike, marrow plasma cell% and presence of high risk FISH were enrolled provided they had adequate marrow and organ function. Patients with significant comorbidities such as heart disease were excluded from the trial. Treatment consisted of three phases: induction, consolidation and maintenance. Patients received carfilzomib (36 mg/m2 twice weekly or as per updated protocol 56mg/m2 weekly for 2 weeks), lenalidomide (25 mg daily for three weeks), daratumumab (weekly for 8 doses, every other week for 16 weeks) and dexamethasone 40 mg weekly, in 4 week cycles for 6 cycles as part of induction, the same regimen was administered with daratumumab every 4 weeks and dexamethasone 20 mg weekly for another 6 cycles for consolidation. This was followed by 12 cycles of maintenance therapy with lenalidomide (10 mg daily for three weeks), daratumumab (day 1 every other cycle) of a 4-week cycle. Appropriate antiviral, and thrombosis prophylaxis were mandated. The primary endpoint of this trial is the rate of confirmed sCR as best response across all cycles of treatment. We plan to accrue 83 patients to this trial with one-stage binomial trial design to test the null hypothesis that the true success (sCR) proportion is at most 65% and the alternate hypothesis of 80%. Results: Forty-six patients have been accrued to the trial as of July 14, 2020. The median age of the study population is 63 years (range 47 - 76); 70% are male. Overall, 2% have completed the maintenance, 50% have completed the consolidation, 80% have completed the induction and 15% are in the induction phase; only two patients have gone off treatment. The reasons for going off treatment were patient preference. At least one patient needed a dose modification for each drug; 17%, 2%, 13% and 7% required dose reductions for carfilzomib, daratumumab, lenalidomide and dexamethasone respectively. The relative median dose intensity for the drugs were 85%, 92%, 80% and 98% for carfilzomib, daratumumab, lenalidomide and dexamethasone respectively across the delivered cycles. The adverse events seen in at least 5% of the patients are as shown in the figure. A grade 3 or higher AE was seen in 52% of patients. There were no treatment related deaths observed. Response rate and depth have been as expected for this regimen in myeloma and analysis is pending completed accrual. Figure 1 Disclosures Kumar: Adaptive Biotechnologies: Consultancy; Sanofi: Research Funding; Cellectar: Other; Genecentrix: Consultancy; Novartis: Research Funding; Dr. Reddy's Laboratories: Honoraria; AbbVie: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; Tenebio: Other, Research Funding; Merck: Consultancy, Research Funding; Amgen: Consultancy, Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments, Research Funding; Janssen Oncology: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; Takeda: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; Celgene/BMS: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; Kite Pharma: Consultancy, Research Funding; BMS: Consultancy, Research Funding; Karyopharm: Consultancy; MedImmune: Research Funding; Genentech/Roche: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; Oncopeptides: Consultancy, Other: Independent Review Committee; IRC member; Carsgen: Other, Research Funding. Badros:Amgen: Consultancy; University of Maryland: Current Employment. Dhakal:Celgene: Consultancy, Honoraria; Amgen: Consultancy, Other: AdvIsory Board, Research Funding; Janssen: Consultancy, Other: Advisory Board, Research Funding; Takeda: Consultancy, Other: Advisory Board; GSK: Consultancy, Research Funding, Speakers Bureau; Sanofi: Research Funding. Abonour:Celgene: Consultancy; Janssen: Honoraria, Research Funding; Takeda: Consultancy; BMS: Consultancy, Research Funding. Rosenbaum:Celgene: Honoraria; Akcea: Honoraria; Amgen: Research Funding; Janssen: Research Funding; GlaxoSmithKline: Research Funding. Bensinger:GSK: Consultancy, Honoraria, Research Funding, Speakers Bureau; Amgen: Consultancy, Honoraria, Research Funding, Speakers Bureau; Janssen: Consultancy, Honoraria, Research Funding, Speakers Bureau; BMS: Consultancy, Honoraria, Research Funding, Speakers Bureau; Sanofi: Consultancy, Honoraria, Research Funding, Speakers Bureau; Regeneron: Consultancy, Honoraria, Research Funding, Speakers Bureau. Bhutani:Prothena: Other: Clinical Trial Funding to Institute; Sanofi Genzyme: Consultancy; Janssen: Other: Clinical Trial Funding to Institute; BMS: Other: Clinical trial funding to institute, Speakers Bureau; Amgen: Speakers Bureau; MedImmune: Other: Clinical Trial Funding to Institute; Takeda: Other: Clinical trial funding to institute, Speakers Bureau. Jakubowiak:AbbVie, Amgen, BMS/Celgene, GSK, Janssen, Karyopharm: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Adaptive, Juno: Consultancy, Honoraria. Durie:Amgen, Celgene, Johnson & Johnson, and Takeda: Consultancy.

Follicular lymphoma (FL) is an indolent B-cell neoplasm of germinal center origin. Standard treatment regimens consist of anti-CD20 therapy with or without chemotherapy. While high response rates to initial therapy are common, patients ultimately relapse or have progressive disease. Clinical risk factors such as the Follicular Lymphoma International Prognostic Index (FLIPI) have been identified, but there is a need for prognostic and predictive biomarkers. We studied markers of lymphoma cells and tumor microenvironment by immunohistochemistry in tissue samples from patients enrolled in 1 of 4 phase 2 trials of anti–CD20-based biological therapy for previously untreated grades 1 to 2 or 3A FL. Results were correlated with progression-free survival (PFS) and PFS status at 24 months. The 4 trials included 238 patients (51.1% male, median age: 55 y) with stage III, IV, or bulky stage II disease. By FLIPI, 24.6% had low-risk, 56.8% had intermediate-risk, and 18.6% had high-risk disease. The outcome differed significantly for patients treated with lenalidomide and rituximab (CALGB 50803) compared with the other 3 trials (median: PFS not reached vs. 3.0 y, hazard ratio=3.47, 95% confidence interval: 2.11-5.72); therefore, data were stratified by clinical trial (CALGB 50803 vs. all others) and adjusted for FLIPI risk group. Among 154 patients with available tissue, interfollicular BCL6 positivity, interfollicular CD10 positivity, and elevated Ki67 proliferation index ≥30% within neoplastic follicles were each associated with inferior PFS and a high risk of the early event by PFS status at 24 months. We identify promising biomarkers for FL risk stratification that warrant further validation in phase 3 trials.