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Kahl, Brad S

0000-0003-0459-6609

Mayo Clinic

Division of Oncology, Washington University School of Medicine, St. Louis, MO.

Citations 23

Tumor-Immune Signatures of Treatment Resistance to Brentuximab Vedotin with Ipilimumab and/or Nivolumab in Hodgkin Lymphoma
Gonzalez‐Kozlova, Edgar , Huang, Hsin-Hui , Jagede, Opeyemi A. , Tuballes, Kevin , Valle, Diane M. Del , Kelly, Geoffrey , Patel, Manishkumar , Xie, Hui , Harris, Jocelyn , Argueta, Kimberly , Nie, Kai , Barcessat, Vanessa , Moravec, Radim , Ansell, Stephen M. , Yu, Joyce , Cerami, Ethan , Lindsay, James , Wistuba, Ignacio I. , Gnjatic, Sacha , Jegede, Opeyemi A. , Del Valle, Diane M , Altreuter, Jennifer , Duose, Dzifa Y , Kahl, Brad S , Ansell, Stephen M , Yu, Joyce , Cerami, Ethan , Lindsay, James R , Wistuba, Ignacio I , Kim-Schulze, Seunghee , Diefenbach, Catherine S , Gnjatic, Sacha , Kahl, Brad S. , Diefenbach, Catherine

Cancer Research Communications | June 27, 2024 | Volume: 4 | Issue: 7 | Pages: 1726-1737

10.1158/2767-9764.crc-24-0252 Get It

Abstract To investigate the cellular and molecular mechanisms associated with targeting CD30-expressing Hodgkin lymphoma (HL) and immune checkpoint modulation induced by combination therapies of CTLA4 and PD1, we leveraged Phase 1/2 multicenter open-label trial NCT01896999 that enrolled patients with refractory or relapsed HL (R/R HL). Using peripheral blood, we assessed soluble proteins, cell composition, T-cell clonality, and tumor antigen-specific antibodies in 54 patients enrolled in the phase 1 component of the trial. NCT01896999 reported high (>75%) overall objective response rates with brentuximab vedotin (BV) in combination with ipilimumab (I) and/or nivolumab (N) in patients with R/R HL. We observed a durable increase in soluble PD1 and plasmacytoid dendritic cells as well as decreases in plasma CCL17, ANGPT2, MMP12, IL13, and CXCL13 in N-containing regimens (BV + N and BV + I + N) compared with BV + I (P < 0.05). Nonresponders and patients with short progression-free survival showed elevated CXCL9, CXCL13, CD5, CCL17, adenosine–deaminase, and MUC16 at baseline or after one treatment cycle and a higher prevalence of NY-ESO-1-specific autoantibodies (P < 0.05). The results suggest a circulating tumor-immune-derived signature of BV ± I ± N treatment resistance that may be useful for patient stratification in combination checkpoint therapy. Significance: Identification of multi-omic immune markers from peripheral blood may help elucidate resistance mechanisms to checkpoint inhibitor and antibody–drug conjugate combinations with potential implications for treatment decisions in relapsed HL.
Randomized study of induction with bendamustine-rituximab ± bortezomib and maintenance with rituximab ± lenalidomide for MCL
Smith, Mitchell R. , Jegede, Opeyemi A. , Parekh, Samir , Yang, David T. , Hsi, Eric D. , Witzig, Thomas E. , Davé, Sandeep S. , Scott, David W. , Hanson, Curtis A. , Shields, Lale Kostakoglu, Abdel‐Samad, Nizar, Baghdadi, Tareq Al, Blum, Kristie A. , Romer, Mark D., Inwards, David J. , Lerner, Rachel E. , Little, Richard F. , Friedberg, Jonathan W. , Leonard, John P. , Witzig, T.E. , Yang, David , Hsi, Eric D , Scott, David W , Hanson, Curtis, Casulo, Carla , Wagner, Lynne , Little, Richard F , Kahl, Brad S , Jagede, Opeyemi A. , Parekh, Samir , Baghdadi, Tareq Al , Martin, Peter, Till, Brian G. , Casulo, Carla , Bartlett, Nancy L. , Caimi, Paolo F. , Wagner, Lynne I. , Kahl, Brad S.

Blood | May 31, 2024 | Volume: 144 | Issue: 10 | Pages: 1083-1092

10.1182/blood.2024023962 Get It

Abstract Although initial therapy of mantle cell lymphoma (MCL) is not standardized, bendamustine plus rituximab (BR) is commonly used in older patients. Rituximab (R) maintenance after induction is often used. Thus, the open-label, randomized phase 2 ECOG-ACRIN Cancer Research Group E1411 trial was designed to test 2 questions: (1) does addition of bortezomib to BR induction (BVR) and/or (2) addition of lenalidomide to rituximab (LR) maintenance improve progression-free survival (PFS) in patients with treatment-naïve MCL? From 2012 to 2016, 373 previously untreated patients, 87% aged ≥60 years, were enrolled in this trial. At a median follow-up of 7.5 years, there is no difference in the median PFS of BR compared with BVR (5.5 vs 6.4 years; hazard ratio [HR], 0.90; 90% confidence interval [CI], 0.70-1.16). There were no unexpected additional toxicities with BVR treatment compared with BR, with no impact on total dose/duration of treatment received. Independent of the induction treatment, addition of lenalidomide did not significantly improve PFS, with median PFS in R vs LR (5.9 vs 7.2 years; HR, 0.84; 90% CI, 0.62-1.15). Most patients completed the planned 24 cycles of LR at the scheduled dose. In summary, adding bortezomib to BR induction does not prolong PFS in treatment-naïve MCL, and LR maintenance was not associated with longer PFS compared with R alone after BR. Nonetheless, the >5-year median PFS outcomes in this prospective cooperative group trial indicate the efficacy of BR followed by R maintenance as highly effective initial therapy for older patients with MCL. This trial was registered at www.clinicaltrials.gov as #NCT01415752.
Myeloablative vs nonmyeloablative consolidation for primary central nervous system lymphoma: results of Alliance 51101
Batchelor, Tracy T. , Giri, Sharmila, Ruppert, Amy S. , Geyer, Susan M. , Smith, Scott E. , Mohile, Nimish, Swinnen, Lode J., Friedberg, Jonathan W. , Kahl, Brad S. , Bartlett, Nancy L. , Cheson, Bruce D. , Wagner‐Johnston, Nina D. , Nayak, Lakshmi , Leonard, John P. , Rubenstein, James L. , Hsi, Eric D , Wagner-Johnston, Nina , Bartlett, Nancy L , Kahl, Brad S , Hsi, Eric D.

Blood Advances | April 10, 2024 | Volume: 8 | Issue: 12 | Pages: 3189-3199

10.1182/bloodadvances.2023011657 Get It

Abstract Although it is evident that standard-dose whole-brain radiotherapy as consolidation is associated with significant neurotoxicity, the optimal consolidative strategy for primary central nervous system lymphoma (PCNSL) is not defined. We performed a randomized phase 2 clinical trial via the US Alliance cancer cooperative group to compare myeloablative consolidation supported by autologous stem cell transplantation with nonmyeloablative consolidation after induction therapy for PCNSL. To our knowledge, this is the first randomized trial to be initiated that eliminates whole-brain radiotherapy as a consolidative approach in newly diagnosed PCNSL. Patients aged 18 to 75 years were randomly assigned in a 1:1 manner to induction therapy (methotrexate, temozolomide, rituximab, and cytarabine) followed by consolidation with either thiotepa plus carmustine and autologous stem cell rescue vs induction followed by nonmyeloablative, infusional etoposide plus cytarabine. The primary end point was progression-free survival (PFS). A total of 113 patients were randomized, and 108 (54 in each arm) were evaluable. More patients in the nonmyeloablative arm experienced progressive disease or death during induction (28% vs 11%; P = .05). Thirty-six patients received autologous stem cell transplant, and 34 received nonmyeloablative consolidation. The estimated 2-year PFS was higher in the myeloablative vs nonmyeloablative arm (73% vs 51%; P = .02). However, a planned secondary analysis, landmarked at start of the consolidation, revealed that the estimated 2-year PFS in those who completed consolidation therapy was not significantly different between the arms (86% vs 71%; P = .21). Both consolidative strategies yielded encouraging efficacy and similar toxicity profiles. This trial was registered at www.clininicals.gov as #NCT01511562.
The Lymphoma Epidemiology of Outcomes cohort study: Design, baseline characteristics, and early outcomes
Cerhan, James R. , Maurer, Matthew J. , Link, Brian K. , Feldman, Andrew L. , Habermann, Thomas M. , Jaye, David L. , Burack, Richard , McDonnell, Timothy J. , Vega, Francisco , Chapman, Jennifer R. , Leonard, John P. , Bernal‐Mizrachi, Leon , Alderuccio, Juan Pablo , Riska, Shaun M., Gysbers, Brianna, Lunde, Julianne J. , Reicks, Tanner W., Ayers, Amy , O’Leary, Colin B. , Yost, Kathleen J. , Nowakowski, Grzegorz S. , Ruan, Jia , Koff, Jean L. , Thompson, Carrie A. , Cohen, Jonathon B. , Lossos, Izidore S. , Friedberg, Jonathan W. , Martin, Peter W., Flowers, Christopher R. , Burack, W Richard , Syrbu, Sergei , Vij, Kiran R , Bernal-Mizrachi, Leon , Witzig, T.E. , Weiner, George , Wang, Yucai , Alderuccio, Juan Pablo , Slager, Susan L , Liu, Hongfang , Chihara, Dai , Koff, Jean L , Casulo, Carla , Thompson, Carrie A , Cohen, Jonathon B , Kahl, Brad S , Lossos, Izidore S , Feldman, Andrew L , Maurer, Matthew , Cerhan, James R , Vega, Francisco , Link, Brian K , Habermann, Thomas , Jaye, David L , Syrbu, Sergei , Inghirami, Giorgio , Farooq, Umar , Witzig, Thomas E. , Weiner, George J. , Wang, Yucai , Slager, Susan L. , Larson, Melissa C. , Liu, Hongfang , Chihara, Dai , Casulo, Carla , Kahl, Brad S. , Nastoupil, Loretta J. , Martin, Peter

American Journal of Hematology | January 13, 2024 | Volume: 99 | Issue: 3 | Pages: 408-421

10.1002/ajh.27202 Get It

AbstractTo address the current and long‐term unmet health needs of the growing population of non‐Hodgkin lymphoma (NHL) patients, we established the Lymphoma Epidemiology of Outcomes (LEO) cohort study (NCT02736357; https://leocohort.org/). A total of 7735 newly diagnosed patients aged 18 years and older with NHL were prospectively enrolled from 7/1/2015 to 5/31/2020 at 8 academic centers in the United States. The median age at diagnosis was 62 years (range, 18–99). Participants came from 49 US states and included 538 Black/African‐Americans (AA), 822 Hispanics (regardless of race), 3386 women, 716 age <40 years, and 1513 rural residents. At study baseline, we abstracted clinical, pathology, and treatment data; banked serum/plasma (N = 5883, 76.0%) and germline DNA (N = 5465, 70.7%); constructed tissue microarrays for four major NHL subtypes (N = 1189); and collected quality of life (N = 5281, 68.3%) and epidemiologic risk factor (N = 4489, 58.0%) data. Through August 2022, there were 1492 deaths. Compared to population‐based SEER data (2015–2019), LEO participants had a similar distribution of gender, AA race, Hispanic ethnicity, and NHL subtype, while LEO was underrepresented for patients who were Asian and aged 80 years and above. Observed overall survival rates for LEO at 1 and 2 years were similar to population‐based SEER rates for indolent B‐cell (follicular and marginal zone) and T‐cell lymphomas, but were 10%–15% higher than SEER rates for aggressive B‐cell subtypes (diffuse large B‐cell and mantle cell). The LEO cohort is a robust and comprehensive national resource to address the role of clinical, tumor, host genetic, epidemiologic, and other biologic factors in NHL prognosis and survivorship.
Long-Term Follow-Up of the RESORT Study (E4402): A Randomized Phase III Comparison of Two Different Rituximab Dosing Strategies for Low–Tumor Burden Follicular Lymphoma
Kahl, Brad S. , Jegede, Opeyemi A. , Peterson, Christopher G., Swinnen, Lode J., Weiss, Matthias , Fishkin, Paul A. S., Fenske, Timothy S. , Williams, Michael E. , Weiss, Matthias , Fenske, Timothy S , Williams, Michael E , Jagede, Opeyemi A. , Kahl, Brad S , Peterson, Christopher, Habermann, Thomas M. , Schuster, Stephen J.

Journal of Clinical Oncology | January 9, 2024 | Volume: 42 | Issue: 7 | Pages: 774-778

10.1200/jco.23.01912 Get It

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical trial updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported. In 2003, the Eastern Cooperative Oncology Group initiated a randomized phase III clinical trial (E4402) comparing two different rituximab dosing strategies for patients with previously untreated low–tumor burden follicular lymphoma. Rituximab-responsive patients (n = 299) were randomly assigned to either a retreatment rituximab (RR) strategy or a maintenance rituximab (MR) strategy. Each dosing strategy was continued until treatment failure. The primary end point of the study was time to treatment failure (TTF). In the original report, there was no difference in TTF between the two dosing strategies. Here, we report on the long-term outcomes for secondary end points of time to first cytotoxic therapy, duration of response, and overall survival (OS). At 7 years, 83% of MR patients had not required first chemotherapy compared with 63% of RR patients (hazard ratio, 2.37 [95% CI, 1.5 to 3.76]). At 7 years, 71% of MR remained in their first remission compared with 37% of RR patients. Despite the improved first remission length with MR, there was no difference in OS at 10 years (83% v 84%). With mature long-term data, we confirm that prolonged maintenance rituximab does not confer an OS advantage in low–tumor burden follicular lymphoma.
Mutations associated with progression in follicular lymphoma predict inferior outcomes at diagnosis: Alliance A151303
Russler‐Germain, David A. , Krysiak, Kilannin , Ramirez, Cody A. , Watkins, Marcus P. , Gomez, Felicia , Trani, Lee , Geyer, Susan M. , Cashen, Amanda F. , Mehta–Shah, Neha , Alderuccio, Juan Pablo , Lossos, Izidore S. , Ondrejka, Sarah L. , Leonard, John P. , Griffith, Malachi , Griffith, Obi L. , Fehniger, Todd A. , Ramirez, Cody , Watkins, Marcus , Gomez, Felicia , Mehta-Shah, Neha , Kahl, Brad S , Bartlett, Nancy L , Alderuccio, Juan Pablo , Lossos, Izidore S , Ondrejka, Sarah , Hsi, Eric D , Griffith, Obi L , Fehniger, Todd A , Krysiak, Kilannin , Griffith, Malachi , Russler-Germain, David A , Mosior, Matthew , Skidmore, Zachary L. , Gao, Feng , Kahl, Brad S. , Bartlett, Nancy L. , Hsi, Eric D. , Martin, Peter

Blood Advances | July 26, 2023 | Volume: 7 | Issue: 18 | Pages: 5524-5539

10.1182/bloodadvances.2023010779 Get It

Abstract Follicular lymphoma (FL) is clinically heterogeneous, with select patients tolerating extended watch-and-wait, whereas others require prompt treatment, suffer progression of disease within 24 months of treatment (POD24), and/or experience aggressive histologic transformation (t-FL). Because our understanding of the relationship between genetic alterations in FL and patient outcomes remains limited, we conducted a clinicogenomic analysis of 370 patients with FL or t-FL (from Cancer and Leukemia Group B/Alliance trials 50402/50701/50803, or real-world cohorts from Washington University School of Medicine, Cleveland Clinic, or University of Miami). FL subsets by grade, stage, watch-and-wait, or POD24 status did not differ by mutation burden, whereas mutation burden was significantly higher in relapsed/refractory (rel/ref) FL and t-FL than in newly diagnosed (dx) FL. Nonetheless, mutation burden in dx FL was not associated with frontline progression-free survival (PFS). CREBBP was the only gene more commonly mutated in FL than in t-FL yet mutated CREBBP was associated with shorter frontline PFS in FL. Mutations in 20 genes were more common in rel/ref FL or t-FL than in dx FL, including 6 significantly mutated genes (SMGs): STAT6, TP53, IGLL5, B2M, SOCS1, and MYD88. We defined a mutations associated with progression (MAP) signature as ≥2 mutations in these 7 genes (6 rel/ref FL or t-FL SMGs plus CREBBP). Patients with dx FL possessing a MAP signature had shorter frontline PFS, revealing a 7-gene set offering insight into FL progression risk potentially more generalizable than the m7–Follicular Lymphoma International Prognostic Index (m7-FLIPI), which had modest prognostic value in our cohort. Future studies are warranted to validate the poor prognosis associated with a MAP signature in dx FL, potentially facilitating novel trials specifically in this high-risk subset of patients.
Impact of diagnosis to treatment interval in patients with newly diagnosed mantle cell lymphoma
Switchenko, Jeffrey M. , Bachanová, Veronika , Gerson, James N. , Gordon, Max J. , Danilov, Alexey V. , Grover, Natalie S. , Mathews, Stephanie , Burkart, Madelyn , Hill, Brian T. , Park, Steven , Fenske, Timothy S. , Martin, Peter W., Malecek, Mary‐Kate , Flowers, Christopher R. , Link, Brian K. , Kaplan, Lawrence D. , Inwards, David J. , Maddocks, Kami J. , Blum, Kristie A. , Bartlett, Nancy L. , Leonard, John P. , Cohen, Jonathon B. , Epperla, Narendranath , Switchenko, Jeffrey , Grover, Natalie S , Burkart, Madelyn , Karmali, Reem , Sawalha, Yazeed , Ghosh, Nilanjan , Park, Steven I , Bond, David A , Hamadani, Mehdi , Kahl, Brad S , Link, Brian K , Feldman, Andrew L , Hsi, Eric D , Bartlett, Nancy L , Cerhan, James R , Maurer, Matthew , Cohen, Jonathon B , Bachanova, Veronika , Epperla, Narendranath , Barta, Stefan K , Karmali, Reem , Sawalha, Yazeed , Bond, David A. , Hamadani, Mehdi , Martin, Peter, Kahl, Brad S. , Feldman, Andrew L. , Hsi, Eric D. , Cerhan, James R. , Habermann, Thomas M. , Maurer, Matthew J.

Blood Advances | December 14, 2022 | Volume: 7 | Issue: 11 | Pages: 2287-2296

10.1182/bloodadvances.2022009225 Get It

Abstract The prognostic relevance of diagnosis to treatment interval (DTI) in patients with newly diagnosed mantle cell lymphoma (MCL) is unknown. Hence, we sought to evaluate the impact of DTI on outcomes in MCL using 3 large datasets (1) the University of Iowa/Mayo Clinic Specialized Program of Research Excellence Molecular Epidemiology Resource, (2) patients enrolled in the ALL Age Asthma Cohort/CALGB 50403, and (3) a multisitecohort of patients with MCL. Patients were a priori divided into 2 groups, 0 to 14 days (short DTI) and 15 to 60 days (long DTI). The patients in whom observation was deemed appropriate were excluded. One thousand ninety-seven patients newly diagnosed with MCL and available DTI were included in the study. The majority (73%) had long DTI (n=797). Patients with short DTI had worse eastern cooperative oncology group performance status (ECOG PS ≥2), higher lactate dehydrogenase, bone marrow involvement, more frequent B symptoms, higher MCL International Prognostic Index (MIPI ≥6.2), and were less likely to receive intensive induction therapy than long DTI group. The median progression-free survival (2.5 years vs 4.8 years, p&lt;0.0001) and overall survival (7.8 years vs. 11.8 years, p&lt;0.0001) were significantly inferior in the short DTI group than the long DTI cohort and remained significant for progression-free survival and overall survival in multivariable analysis. We show that the DTI is an important prognostic factor in patients newly diagnosed with MCL and is strongly associated with adverse clinical factors and poor outcomes. DTI should be reported in all the patients newly diagnosed with MCL who are enrolling in clinical trials and steps must be taken to ensure selection bias is avoided.
Evaluating the impact of eligibility criteria in first-line clinical trials for follicular lymphoma: a MER/LEO cohort analysis
Fatola, Tolulope, Toure, Ahmed, Flowers, Christopher R. , Link, Brian K. , Friedberg, Jonathan W. , Cohen, Jonathon B. , Kahl, Brad S. , Lossos, Izidore S. , Martin, Peter , Link, Brian K , Cohen, Jonathon B , Kahl, Brad S , Lossos, Izidore S , Maurer, Matthew , Cerhan, James R , Luan, Danny , Nastoupil, Loretta J. , Maurer, Matthew J. , Cerhan, James R.

Blood Advances | July 6, 2022 | Volume: 6 | Issue: 15 | Pages: 4413-4423

10.1182/bloodadvances.2022007687 Get It

Abstract Cancer clinical trial eligibility criteria may create patient populations studied in trials that do not reflect the patient populations treated in the real-world setting. Follicular lymphoma (FL) is an indolent lymphoma with heterogeneous presentations across a broad range of individuals, resulting in many acceptable management strategies. We evaluated how first-line clinical trial eligibility criteria impacted the demographic makeup and outcomes of patients with FL for whom systemic therapy might be considered. We compared the characteristics of 196 patients with FL from a single institution to eligibility criteria from 10 first-line FL trials on clinicaltrials.gov. Next, we tabulated eligibility criteria from 24 first-line FL protocols and evaluated their impact on 1198 patients with FL with stages II to IV disease from the prospective Molecular Epidemiology Resource (MER) and Lymphoma Epidemiology of Outcomes (LEO) cohort studies. We found that 39.8% and 52.7% of patients with FL might be excluded from clinical trials based on eligibility criteria derived from clinicaltrials.gov and protocol documents, respectively. Patients excluded because of renal function, prior malignancy, and self-reported serious health conditions tended to be older. Expanding stage requirement from III-IV to II-IV, and platelet requirement from ≥150 000 to ≥75 000 increased population size by 21% and 8%, respectively, in MER and by 16% and 13%, respectively, in LEO, without impacting patient demographics or outcomes. These data suggest that management of older individuals with FL may not be fully informed by recent clinical trials. Moreover, liberalizing stage and platelet criteria might expand the eligible population and allow for quicker trial accrual without impacting outcomes.
Relevance of Bone Marrow Biopsies for Response Assessment in US National Cancer Institute National Clinical Trials Network Follicular Lymphoma Clinical Trials
Rutherford, Sarah C. , Yin, Jun , Pederson, Levi , Burbano, Gabriela Perez , LaPlant, Betsy, Kenkre, Vaishalee P. , Hong, Fangxin , Blum, Kristie A. , Dockter, Travis , Martin, Peter , Grant, Barbara, Rosenbaum, Cara A. , Ujjani, Chaitra S. , Cheson, Bruce D. , Bartlett, Nancy L. , Friedberg, Jonathan W. , Mandrekar, Sumithra J. , Leonard, John P. , Perez Burbano, Gabriela, Hong, Fangxin , Blum, Kristie A , Dockter, Travis , Martin, Peter , Jung, Sin‐Ho , Rosenbaum, Cara , Barr, Paul M , Unger, Joseph M , Cheson, Bruce D , Bartlett, Nancy L , Kahl, Brad S , Mandrekar, Sumithra J , Shadman, Mazyar , Li, Hongli , LeBlanc, Michael , Barr, Paul M. , Unger, Joseph M. , Kahl, Brad S.

Journal of Clinical Oncology | July 5, 2022 | Volume: 41 | Issue: 2 | Pages: 336-342

10.1200/jco.21.02301 Get It

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.