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Bartlett, Nancy L.

https://orcid.org/0000-0001-8470-394X

A5078397650 | I204465549

Mayo Clinic

Washington University in St. Louis

Citations 154

The Role Of Body Mass Index In Survival Outcome For Lymphoma Patients: US Intergroup Experience

Blood | October 14, 2019 | Volume: 122 | Issue: 21 | Pages: 3060-3060

10.1182/blood.v122.21.3060.3060

Abstract Introduction The role of body mass index (BMI) impacting clinical outcome among lymphoma patients is controversial. Two recent studies suggest that increased BMI is associated with significantly improved survival. In this study the association between BMI at study entry and failure-free survival (FFS) and overall survival (OS) was evaluated in three phase III Eastern Cooperative Oncology Group-led trials, among patients with DLBCL (E4494), follicular lymphoma (FL) (E1496) and Hodgkin's lymphoma (HL) (E2496). Patients and Methods 537 patients with DLBCL, 730 patients with HD and 282 patients with FL were included in the analysis. BMI was calculated as weight (kilograms) divided by the square of height (meters), using data at study entry. BMI was analyzed both as continuous and categorical variables (underweight <18.5 kg/m2, normal weight: 18.5 to < 25 kg/ m2, overweight: 25 to < 30 kg/ m2, and obese :≥ 30 kg/ m2).The underweight group was excluded due to low (< 2%) prevalence. Baseline patient and clinical characteristics, treatment received and clinical outcomes were compared across BMI categories. PFS was defined as the time from study entry to relapse, progression, or death. OS was measured from study entry to death of any cause. The log-rank test and Cox regression models was used to check the association. The association between BMI and FFS/OS was also independently assessed among patients treated with rituximab. A sensitivity analysis was performed excluding patients with significant weight loss at baseline. Results Among patients with DLBCL, HL and FL, the median age was 70, 33 and 56; 29%, 29% and 37% were obese and 38%, 27% and 37% were overweight, respectively. Age was significantly different among BMI groups in all three studies. Higher BMI groups tended to have better prognosis at study entry among DLBCL and HL patients. BMI was not associated with clinical outcome, with p-values of 0.89, 0.30 and 0.40 for FFS, and p-values of 0.64, 0.67 and 0.09 for OS, for patients with DLBCL, HL and FL, respectively (Figure 1). In multivariate analysis adjusting for other clinical factors, BMI remains an insignificant predictor for all three histologies (Table 1). When limiting to patients treated with rituximab, the association remains non-significant for both FL patients (p=0.92 for PFS, p=0.36 for OS) and DLBCL patients (Figure 2). A subset analysis of males with DLBCL treated on R-CHOP, which matched the study cohort used in a recent report (Carson et al, 2012), revealed no differences in FFS (p=0.48) or OS (p=0.58) (Figure 2). Sensitivity analysis excluding patients with weight loss at study entry resulted in similar findings. Conclusion BMI was not significantly associated with clinical outcomes among patients with DLBCL, HL or FL, in three prospective phase III clinical trials. The findings contradict some previous reports of similar investigations. Further work is required to understand the observed discrepancies. Disclosures: Horning: Genentech: Employment.
Lymphoma in Pregnancy: Excellent Fetal Outcomes and Maternal Survival in a Large Multicenter Analysis

Blood | October 14, 2019 | Volume: 118 | Issue: 21 | Pages: 94-94

10.1182/blood.v118.21.94.94

Abstract Abstract 94 Background: Lymphoma diagnosed during pregnancy is a rare occurrence. Further, there is heterogeneity in clinical presentation and a range of lymphoma histologies resulting in a continued deficiency of lymphoma-specific data in the literature regarding prognosis, optimal therapy, maternal complications, and fetal outcome. Methods: A comprehensive retrospective analysis was completed for patients (pts) diagnosed (dx) with Hodgkin lymphoma (HL) or non-Hodgkin lymphoma (NHL) during pregnancy at 9 large U.S. academic centers over a 13-year period (1998–2011). The vast majority of cases were co-managed with high-risk maternal fetal medicine. Data on maternal disease characteristics, treatment details, obstetric complications, and fetal outcomes were analyzed. Results: 88 cases were identified with complete data available in 82. The median age of pts was 31 yrs (18–40). Lymphoma dx occurred at a median of 24 weeks (wks) gestation (5–40). 15% of pts were dx during the 1st trimester, 46% during the 2nd trimester, 35% during the 3rd trimester, while 4% (n=3) of pts had a pre-existing NHL dx (follicular lymphoma (FL)). 52% (n=43) of pts had NHL and 48% (n=39) HL. Of NHL cases, 83% (n=33) were B-cell and 17% (n=10) T-cell. B-cell histologies were DLBCL n=23 (including 2 primary CNS and 1 'double hit' NHL), FL n=5 (including 1 leukemic phase FL), Burkitt's lymphoma n=3, and mixed histology n=1; T-cell histologies were anaplastic large cell n=6, PTCL not otherwise specified n=2, and T-cell/NK NHL n=2. Pts with B-cell NHL and HL were dx at a median age of 29 yrs (range, 18–40), while T-cell NHL pts were dx at a median of 34 years (19–37). MRI without gadolinium was the most common imaging modality utilized for staging. 63% of NHL and 19% of HL pts had stage III/IV disease (25% of HL with stage IIB). Pregnancy was terminated in 6 pts (n=4 aggressive NHL and n=2 HD) to enable immediate chemotherapy (five in the 1st trimester [at 5, 8, 10, 10, and 12 wks] and 1 pt in the early 2nd trimester who required high-dose methotrexate). 48 pts (63%) initiated anti-lymphoma therapy at a median of 25 wks gestation (range, 13–37) with 79% of pts initiating therapy in the 2nd trimester (see Table 1). The median gestation at time of lymphoma dx for pts who received intra-partum treatment was 20 wks vs 34 wks for pts who had therapy deferred to post-delivery (p<0.0001). The overall response rate among pts who received therapy was 87% (74% complete remission). Notably, gestation went to full-term in 54% with delivery occurring at a median of 37 wks (31–40). Therapy was deferred until post-delivery in 28 pts (37%) and the majority of these pregnancies were also carried to term (median delivery at 38 wks). At a median follow-up of 41 months (6–157), the 3-year PFS and OS for all pts were 79% and 89% respectively. Histology-specific 3-year PFS and OS were: B-cell NHL: 73% and 82%, respectively; T-cell NHL: 50% and 90%, respectively; and HL: 90% and 95%, respectively (Figure 1). Detailed obstetrical information was available in 59 pts. There were minimal pre-term complications, the most common being induction of labor in 45%. Perinatal events included spontaneous rupture of membranes in 5% and pre-eclampsia in 8%. Further, there were no differences in these events detected among pts who received intra-partum treatment vs deferred therapy. No episodes of chorioamnionitis or endometritis were noted. There was 1 stillbirth that occurred at 19 wks gestation in a 34-year-old pt with double-hit NHL following 1 cycle of R-CHOP. The median birth weight of infants was 2427 grams (1005–5262) with no difference among pts who received intra-partum chemotherapy vs not (2637 grams vs 2212 grams, respectively; p=NS). Microcephaly was reported in 1 case following 4 intra-partum cycles of CHOP for DLBCL; there were otherwise no malformations detected. Conclusions: To our knowledge, this represents one of the largest experiences reported of lymphoma in pregnancy. Our data show that standard NHL and HL chemotherapeutic regimens (without anti-metabolites) administered during the 2nd and 3rd trimester, including as early as 13 wks gestation in select cases, is associated with minimal maternal complications or fetal detriment. In addition, pts with low risk clinical scenarios (e.g., indolent NHL and/or late gestational dx) had therapy safely deferred to post-partum. In our experience, this approach was associated with overall expected lymphoma-related survival. Disclosures: No relevant conflicts of interest to declare.
A Phase 1b Clinical Trial of Dacetuzumab in Combination with Rituximab and Gemcitabine: Multiple Responses Observed in Patients with Relapsed Diffuse Large B-Cell Lymphoma.

Blood | October 13, 2019 | Volume: 114 | Issue: 22 | Pages: 586-586

10.1182/blood.v114.22.586.586

Abstract Abstract 586 Background: Dacetuzumab (SGN-40), a humanized monoclonal antibody that targets CD40, mediates antitumor activity through multiple mechanisms of action, including effector cell functions (ADCC/ADCP) and direct apoptotic signal transduction. Ongoing evaluation of the molecule has led to 2 additional key findings: a gene signature that predicts sensitivity to single-agent dacetuzumab, and upregulation of the pro-apoptotic and chemosensitizing transcription factor TAp63αa when dacetuzumab is combined with rituximab (R) and gemcitabine (GEM). In prior single-agent dacetuzumab trials, several patients who were immediately treated with GEM after progressing achieved unexpected responses. These observations provided rationale for further analysis of the combination of dacetuzumab, R and GEM. Methods: A phase 1b dose-escalation study to evaluate the safety and adverse event profile of dacetuzumab, R and GEM was conducted in patients with relapsed diffuse large B-cell lymphoma (DLBCL). Patients received dacetuzumab at cohort-specific doses of 8 or 12 mg/kg IV weekly in combination with R (375 mg/m2 IV for 1 cycle, then once/28-day cycle) and GEM (1000 mg/m2 IV weekly or biweekly) in a 3 + 3 dose-escalation scheme. A maximum number of 8 cycles was permitted. Eligible patients included those with de novo DLBCL, including transformed lymphoma and follicular grade 3, who failed potentially curative therapy. Results: Thirty-one patients with a median age of 68 years (range 29–80) were enrolled and treated in the study (3 patients in each of 3 cohorts + 22 in an expansion cohort). The median number of prior regimens was 3 (range 1–18); 10 patients (32%) had transformed histology and 4 (13%) had prior ASCT. The median number of cycles received was 3 (range 1–8), although 11 patients are still on treatment. Three patients in the first cohort required dose reduction of GEM due to transient, non-dose-limiting thrombocytopenia. The protocol was thus amended to administer GEM on a biweekly schedule. No dose-limiting toxicity was observed, and MTD was not defined. Based on pharmacokinetic modeling suggesting no significant difference in exposure between dose levels, 8 mg/kg of dacetuzumab was chosen as the dose for the expansion cohort. The combination of dacetuzumab, R and GEM was generally well tolerated. Across all cohorts, the most common adverse events (> 15%) were nausea (42%), thrombocytopenia (35%), fatigue (32%), headache (29%), anorexia (19%), dyspnea (19%), pyrexia (19%), diarrhea (16%), and neutropenia (16%), the majority of which were Grade 1 or 2. Grade 3/4 adverse events related to dacetuzumab occurred infrequently. One patient experienced Grade 3 stress cardiomyopathy that resolved; this patient had a history of congestive heart failure. One patient developed pneumonitis in the left lung and acute respiratory distress syndrome, and subsequently died due to pulmonary toxicity; this patient had received prior radiation therapy to the left chest. There was preliminary evidence of antitumor activity. Of the 28 patients with response assessments, 7 patients achieved CR, 8 PR, 7 SD, and 6 PD per investigator assessment of response, yielding an objective response rate of 54%. Of interest, 1 patient who previously failed ASCT achieved a CR and was able to undergo allogeneic transplant. To date, this patient remains in CR. Conclusion: The combination of dacetuzumab, R and biweekly GEM was generally well tolerated. Evidence of antitumor activity with this combination is encouraging as multiple responses were observed in a population with heavily pre-treated patients. Further investigation with a randomized trial is warranted to more fully characterize safety and efficacy and to determine if sensitivity to this combination correlates with the previously identified single-agent predictive gene signature. Disclosures: Forero-Torres: Seattle Genetics, Inc.: Research Funding. Off Label Use: Gemcitabine has not been FDA approved for treatment of lymphoma. Dacetuzumab is an investigational agent.. Bartlett:Seattle Genetics, Inc.: Research Funding. Nasta:Seattle Genetics, Inc.: Research Funding; Genentech: Speakers Bureau. Northfelt:Seattle Genetics, Inc.: Research Funding. Beaven:Seattle Genetics, Inc.: Research Funding. Myint:Seattle Genetics, Inc.: Research Funding. Whiting:Seattle Genetics, Inc.: Employment, Equity Ownership. Drachman:Seattle Genetics, Inc.: Employment, Equity Ownership. Moskowitz:Seattle Genetics, Inc.: Membership on an entity's Board of Directors or advisory committees, Research Funding.
Brentuximab Vedotin with RCHOP As Frontline Therapy in Patients with High-Intermediate/High-Risk Diffuse Large B Cell Lymphoma (DLBCL): Results from an Ongoing Phase 2 Study

Blood | October 12, 2019 | Volume: 126 | Issue: 23 | Pages: 814-814

10.1182/blood.v126.23.814.814

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.
Patterns of Failure in Patients with Stage I/II Bulky Mediastinal Hodgkin Lymphoma (HL) Treated with ABVD + Radiotherapy or the Stanford V Regimen in the Randomized Phase III North American Intergroup Trial: E2496

Blood | October 12, 2019 | Volume: 118 | Issue: 21 | Pages: 1603-1603

10.1182/blood.v118.21.1603.1603

Abstract Abstract 1603 Background: We have previously reported similar outcomes for patients with bulky stage I or II mediastinal HL treated with combined modality therapy either with ABVD + radiotherapy or the Stanford V regimen in the North American Intergroup trial E2496 (Advani et al, ASH 2010 abstract 416). In the current analysis, we compare the patterns of failure between the two groups. Methods: Patients with stage I/II bulky mediastinal HL (maximum mediastinal mass width > 1/3 of intrathoracic diameter) were randomized to receive chemotherapy (CT) on either Arm A (ABVD x 6–8 cycles administered q 28 days) or Arm B (12 weeks of Stanford V administered weekly). Two-3 weeks after completion of chemotherapy all patients received modified involved field radiotherapy (RT) (36 Gy) delivered to the mediastinum, hila, and supraclavicular regions. Patients on Stanford V arm also received involved field RT to any other sites ≥ 5 cm at diagnosis. Patients were assessed 3, 6 and 12 months after completing RT with computed tomography scanning and then every 6 months for 5 years. The primary end points were failure free survival (FFS) and overall survival (OS). Disease progression was defined as 'in-field', 'distant' or both relative to the radiation fields prescribed in the E2496 protocol. Distant sites of failure were further characterized as intra-thoracic, intra-abdominal or other (bone, bone marrow and axillae, if not previously irradiated). Results: Two hundred and sixty-seven patients were randomized: 136 on the ABVD arm and 131 on the Stanford V arm. Patient characteristics were well matched with no differences between two arms in overall response rates (ORR), FFS and OS. (Advani et al ASH 2010 abstract 416). At a median follow up of 5.5 years 40 patients have relapsed with no difference in ABVD (n=18, 13%) versus Stanford V (n=22, 17%) (p=0.49). Central review of RT fields available in 37/40 patients found major violations with under treatment of tumor noted in 7/37 (19%). Patterns of failure are shown in Table 1. There were no differences in patterns of relapse for the two study arms. In-field relapses occurred in <10% in both study arms. Conclusion: For patients with stage I/II bulky mediastinal HL, combined modality therapy with either ABVD +RT or the Stanford V regimen results in excellent disease control. In-field relapse was uncommon. These results set a benchmark for assessing ongoing trials omitting RT in patients with stage I/II bulky mediastinal HL. Future research efforts should focus on risk stratification to identify the small subset of patients who are likely to fail standard upfront therapy. US cooperative group efforts in this subset of patients are ongoing that use interim PET-CT imaging based risk-adapted strategies. Disclosures: Horning: Genentech: Employment, Equity Ownership.
A Randomized Phase III Trial of ABVD Vs. Stanford V +/− Radiation Therapy In Locally Extensive and Advanced Stage Hodgkin's Lymphoma: An Intergroup Study Coordinated by the Eastern Cooperatve Oncology Group (E2496)

Blood | October 12, 2019 | Volume: 116 | Issue: 21 | Pages: 415-415

10.1182/blood.v116.21.415.415

Abstract Abstract 415 Background: The ability to cure patients (pts) with advanced Hodgkin's Lymphoma (HL) with combination chemotherapy (CC) (MOPP and variants, ABVD and variants) represented a major milestone in oncology research, and CC became a paradigm for other malignancies. Further, the rationale for combined modality therapy (CMT) (radiation (RT) and CC) in HL evolved based on the high frequency of relapse in initially involved sites. As response rates and survival improved, newer treatments such as the combined modality Stanford V regimen were developed to shorten the duration of chemotherapy, add RT to sites of disease and reduce toxicity while maintaining or improving the cure rate. Indeed, the Stanford V regimen was tested and validated in a Phase II co-operative group trial (E1492) (J Clin Oncol 2000; 18:972). In order to investigate this approach against “standard” therapy, we conducted a randomized Phase III Intergroup trial of ABVD vs. the Stanford V regimen for patients with locally extensive or advanced HL. Objectives: The trial was designed to detect a 33% reduction in the failure free survival (FFS) hazard rate with Stanford V compared with ABVD, which corresponds to a difference in five-year FFS of 64% vs. 74%. Method: Patients with locally extensive (defined as clinical Ann Arbor Stage I-IIA/B and bulky mediastinal disease (BMD) (mass > 1/3 maximum intrathoracic diameter on standing postero-anterior chest x-ray or >/−10 cm on computerized tomography) or advanced (Ann Arbor Stage III or IV) HL were randomized to receive either ABVD × 6–8 cycles (C) (51% had 6 C, 35% had 8 C, 14% had <6 C) + 36 Gy (only in pts with BMD) or Stanford V × 12 weeks (95% had 12 weeks) + 36 Gy (for sites >5cm or for macroscopic splenic disease). The log-rank test was used to compare FFS for all eligible patients stratified on extent of disease (locally extensive vs. advanced), and number of International Prognostic Factor Project (IPFP) risk factors (0–2 vs. 3–7). An extended Cox model was also used to address non-proportional hazard between the two arms. Results: 854 pts enrolled from April, 1999 to June, 2006 and 812 were eligible for analysis. 404 pts were randomized to ABVD and 408 to Stanford V. Median age was 33 yrs in both arms (range 16–83). 53% were men and 47% women; 4% had Stage I, 31% had Stage II, 39% had Stage III and 25% had Stage IV disease by Ann Arbor criteria. 35% of pts on ABVD and 35% on Stanford V had BMD. Three % of pts had nodular lymphocyte predominant HL, 77% of pts had nodular sclerosis HL, 14% had mixed cell HL. Age, stage, pathology and risk factors (0–2 vs. 3–7) were similar in both arms. In total, 65% were IPFP score 0–2 and 33% were 3–6. Response rate. There was no difference in response rates (RR) between the two arms (ABVD=72% CR+ CCR, 7.7% PR, 7.9% SD; Stanford V= 69 % CR +CCR, 7% PR and 10 % SD. 8% were not evaluable for response on ABVD and 9% on Stanford V. Toxicity was similar in both groups. The most frequent Grade 3 + 4 toxicity was neutropenia, and was similar between the 2 groups (76% Grade 3 + 4 in ABVD and 70% Grade 3+ 4 in Stanford V). Grade 5 toxicity was <1% in both groups. There was, however, more Grade 3 lymphopenia in Stanford V (78% vs. 42%, p< 0.0001) and more Grade 3 +4 sensory neuropathy in Stanford V (10%) than in ABVD (3%) (p< 0.0001). A total of 26 second primary cancers developed, 12 after ABVD and 14 after Stanford V (p=NS). FFS and OS. For 812 eligible patients, with a median follow up of 5.25 years, 5-year FFS was 73% for ABVD and 71% for Stanford V (p=0.29 by log rank) (Figure left); 5-year OS was 88% for ABVD and 87% for Stanford V (p=0.87 by log-rank, HR=0.97, 95% CI: 0.65 to 1.44) (Figure right) indicating no significant difference in either FFS or OS between the 2 arms. Conclusion: In the largest Phase III intergroup trial of HL in North America, there was no significant difference in RR, FFS, OS, and 5-year toxicity when ABVD (+ RT for BMD) is compared with Stanford V (+RT for nodal sites >5 cm and macroscopic splenic disease). There was more Grade 3 lymphopenia (p< 0.0001) and more Grade 3 + 4 sensory neuropathy (p< 0.0001) on Stanford V. Thus ABVD (plus RT for BMD) remains the standard of care because Stanford V did not meet the objective of 33% improvement in FFS. For some patients, Stanford V, when given as described with RT, remains an acceptable alternative. Disclosures: Friedberg: Genentech: Honoraria. Blum:Seattle Genetics: Research Funding; Novartis: Research Funding; Celgene: Research Funding. Horning:Genentech: Employment.
Randomized Phase III Trial Comparing ABVD + Radiotherapy and the Stanford V Regimen In Patients with Stage I/II Bulky Mediastinal Hodgkin Lymphoma: A Subset Analysis of the US Intergroup Trial E2496

Blood | October 12, 2019 | Volume: 116 | Issue: 21 | Pages: 416-416

10.1182/blood.v116.21.416.416

Abstract Abstract 416 Background: Standard therapy for locally extensive Hodgkin Lymphoma (HL) defined as stage I/II with bulky mediastinal disease [mediastinal mass ratio (MMR) > than 1/3 of the chest diameter on standing postero-anterior chest x-ray or 10 cm on computerized tomography] is combined modality therapy (CMT). E2496 was a North American intergroup, randomized phase III study comparing ABVD versus the Stanford V regimen for patients with locally extensive and advanced stage HL. In this subgroup analysis we compare two CMT approaches, ABVD + radiotherapy (RT) and the Stanford V regimen, in patients with stage I/II bulky mediastinal HL. Methods: Patients with stage I/II HL bulky mediastinal disease were randomized to receive chemotherapy (CT) on either Arm A (ABVD × 6–8 cycles administered q 28 days) or Arm B (12 weeks of Stanford V, administered weekly). Two-3 weeks after completion of chemotherapy, modified involved field RT was delivered at 36 Gy to the mediastinum to patients on ABVD as well as Stanford V. Patients on Stanford V also received involved field RT to any other sites >5 cm at diagnosis. The primary endpoint was failure free survival (FFS) defined as the time to either progression/relapse or death. The log-rank test was used to compare FFS and OS (overall survival) for all eligible patients. Results: Of the 812 eligible patients with advanced HL enrolled on the study 267 had locally advanced bulky mediastinal disease: 136 on ABVD and 131 on Stanford V. Patient characteristics between the two randomized groups were well matched with a median age of 30 years and 86% had stage II disease. On ABVD 61% of patients received 6 cycles, 29% 8 cycles of CT and 77% required some dose modification. In Stanford V 97% completed the assigned 12 weeks of CT and 76% required some dose modification. 82% received RT per protocol in ABVD versus 88% in Stanford V. The overall response (CR+PR) was 82% in ABVD and 86% in Stanford V. At a median follow-up of 5.47 years, there are 19 failures and 6 deaths in the ABVD group and 25 failures with 9 deaths in the Stanford V group. We failed to detect statistically significant differences between ABVD +RT and Stanford V for FFS (5y 85% versus 77% p=0.13, HR=1.56 95% CI (0.87, 2.88) and OS (5y 95% versus 92% p=0.31, HR=1.69 95% CI (0.60, 4.75). No difference in hematologic toxicity was observed between the two arms. Evaluation of pulmonary function and patterns of failure are pending. Conclusions: For stage I/II patients with bulky mediastinal disease, CMT with either ABVD +RT or the Stanford V regimen results in high cure rates and is highly effective. ABVD for 6–8 cycles plus 36 Gy RT remains the US standard of care. Longer follow up is required to assess RT related late effects. Future research efforts should focus on risk stratification to identify; a) the 15–20% of patients destined to relapse after standard therapy and evaluate treatment intensification strategies and b) the 80–85% of patients who are cured with standard therapy and determine whether a subset can achieve the same excellent outcomes with a reduction or elimination of radiation. Planned US cooperative group trials will address these questions, using ABVD as the chemotherapy backbone in conjunction with interim PET imaging for risk stratification. Disclosures: Blum: Seattle Genetics: Research Funding; Novartis: Research Funding; Celgene: Research Funding. Horning:Genentech: Employment.
Insights into the Management of Adverse Events in Patients with Previously Treated Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma: Experience from the Phase 3 HELIOS Study of Ibrutinib Combined with Bendamustine/Rituximab

Blood | October 12, 2019 | Volume: 126 | Issue: 23 | Pages: 2936-2936

10.1182/blood.v126.23.2936.2936

Abstract Introduction Ibrutinib has become a new standard of care in patients with previously treated CLL/SLL based on the phase 3 RESONATE study (Byrd, et al. NEJM 2014) and other trials evaluating ibrutinib mainly as a single agent in CLL. The first randomized, double-blind, placebo-controlled phase 3 study (HELIOS) investigating ibrutinib in combination with bendamustine and rituximab (BR) was recently reported (Chanan-Khan, et al. ASCO 2015), with ibrutinib significantly extending progression-free survival and reducing the risk of progression/death by 80%. The study design provides an opportunity to examine the overall safety and management of adverse events (AEs) with ibrutinib and placebo in a blinded manner that previously has not been possible. Here we examine the safety and management of AEs with ibrutinib + BR vs placebo + BR in HELIOS. Methods Patients with active CLL/SLL following ≥ 1 prior line of systemic therapy were randomized 1:1 to receive BR (≤ 6 cycles) with either ibrutinib 420 mg daily or placebo (n = 289 in each group). Safety was a secondary end point. Results Median exposure to ibrutinib and placebo was 14.7 and 12.8 months, respectively. Rates of infection in the ibrutinib + BR and placebo + BR arms were similar (all-grade, 70.4%; grade ≥ 3, 26.8% vs all-grade, 70.0%; grade ≥ 3, 22.6%, respectively) but exposure-adjusted analysis reveals an overall lower rate of infections with ibrutinib + BR vs placebo + BR (10.3/100 vs 11.2/100 patient-months), with similar rates of grade ≥ 3 infections (2.4/100 patient-months each arm). Rates of all-grade (grade 3/4) anemia were 22.3% (3.5%) with ibrutinib + BR and 28.9% (8.0%) with placebo + BR. Patients also required fewer transfusions with ibrutinib + BR (23%) vs placebo + BR (29%), the majority of which were red blood cell transfusions. Similar proportions of patients used growth factors in both arms (54% vs 52%, respectively). Grade 3/4 neutropenia was reported at similar rates in both arms (53.7% vs 50.5%, respectively); however, fewer patients discontinued due to treatment-related neutropenia with ibrutinib + BR (1.0%) vs placebo + BR (2.8%). Rates of thrombocytopenia were slightly higher with ibrutinib + BR (30.7%) than placebo + BR (24.0%), but rates of grade 3/4 events were similar between arms (15.0% each arm). Atrial fibrillation (AF) was observed more frequently in patients on ibrutinib + BR than placebo + BR (7.3% vs 2.8% overall and 2.8% vs 0.7% grade 3/4, respectively). However, only 4 patients with grade 3/4 AF discontinued therapy in the ibrutinib arm. No patients with grade 1/2 AF discontinued treatment. One-third of patients held ibrutinib treatment to manage AF, with all restarting at the same dose (420 mg). Median (range) time to onset was 3.0 (0.3-17.5) months with ibrutinib + BR and 2.4 (0.6-18.9) months with placebo + BR. Importantly, in those with a prior history of AF or abnormal heart rhythm, only 7/25 receiving ibrutinib + BR and 2/22 receiving placebo + BR developed AF/atrial flutter on study. The rates of any-grade bleeding were 31.0% and 14.6%, respectively, with the majority being grade 1 (77.5% and 69.0%, respectively). Low rates of grade 3/4 major bleeding were observed in the ibrutinib + BR (2.1%) and placebo + BR (1.7%) arms. Many patients (41.8% ibrutinib + BR, 41.1% placebo + BR) were receiving concomitant anticoagulant/antiplatelet medication. A low rate of treatment-related lymphocytosis was observed in both arms (7.0% ibrutinib + BR, 5.9% placebo + BR). The majority of cases resolved within 2 weeks. Conclusions In this randomized, double-blind, placebo-controlled trial, the addition of ibrutinib to BR was well tolerated and did not significantly impact the safety profile of BR. In addition, ibrutinib was associated with reduced rates of anemia and transfusional support. Consistent with its known toxicity profile, patients in the ibrutinib + BR arm had higher rates of bleeding (mostly grade 1 or 2) and AF; however, few patients discontinued therapy as a result of these AEs. A prior history of AF or abnormal heart rhythm did not lead to recurrent episodes in the majority of cases. Taken together, the results from HELIOS establish the significant efficacy of ibrutinib and also the overall positive risk-benefit profile of ibrutinib + BR. Disclosures Cramer: Janssen: Other: Travel grant, Research Funding, Speakers Bureau; Hoffman LaRoche: Other: Travel grant, Research Funding, Speakers Bureau; Astellas: Other: Travel grant; Glaxo Smith Klein/Novartis: Research Funding; Gilead: Other: Travel grant, Research Funding; Mundipharma: Other: Travel grant. Demirkan:Celgene: Other: Travel reimbursement; Amgen: Consultancy. Fraser:Hoffman LaRoche: Consultancy, Honoraria; Janssen: Honoraria, Research Funding, Speakers Bureau; Celgene: Honoraria, Research Funding. Santucci Silva:Janssen: Other: Travel reimbursement, Research Funding; GSK: Research Funding; Celgene: Research Funding; Merck: Research Funding; Novartis: Other: Travel reimbursement; Hoffman LaRoche: Other: Travel reimbursement, Research Funding. Janssens:Roche: Consultancy, Speakers Bureau; Mundipharma: Speakers Bureau; Janssen: Consultancy. Goy:Allos, Biogen Idec, Celgene, Genentech, and Millennium. Gilead: Speakers Bureau; Celgene: Consultancy, Research Funding, Speakers Bureau. Mayer:Janssen: Research Funding. Dilhuydy:Roche: Honoraria, Other: Travel reimbursement; Janssen: Honoraria, Other: Travel reimbursement; Mundipharma: Honoraria. Bartlett:Medimmune: Research Funding; Novartis: Research Funding; Pfizer: Research Funding; Genentech: Research Funding; ImaginAB: Research Funding; Astra Zeneca: Research Funding; Pharmacyclics: Research Funding; Janssen: Research Funding; Gilead: Consultancy; Seattle Genetics: Consultancy, Research Funding; Millenium: Research Funding; Celgene: Research Funding. Rule:Roche: Consultancy, Other: Travel reimbursement; Gilead: Research Funding; Celgene: Consultancy, Other: Travel reimbursement; J&J: Consultancy, Other: Travel reimbursement, Research Funding. Sun:Janssen/J&J: Employment, Equity Ownership. Phelps:Janssen/J&J: Employment, Equity Ownership. Mahler:Janssen: Employment, Other: Travel reimbursement. Salman:Janssen/J&J: Employment, Equity Ownership. Howes:Janssen/J&J: Employment, Equity Ownership. Hallek:AbbVie: Honoraria, Other: Speakers Bureau and/or Advisory Boards, Research Funding; Roche: Honoraria, Other: Speakers Bureau and/or Advisory Boards, Research Funding; Gilead: Honoraria, Other: Speakers Bureau and/or Advisory Boards, Research Funding; Pharmacyclics: Honoraria, Other: Speakers Bureau and/or Advisory Boards, Research Funding; Celgene: Honoraria, Other: Speakers Bureau and/or Advisory Boards, Research Funding; Boehringher Ingelheim: Honoraria, Other: Speakers Bureau and/or Advisory Boards; Mundipharma: Honoraria, Other: Speakers Bureau and/or Advisory Boards, Research Funding; Janssen: Honoraria, Other: Speakers Bureau and/or Advisory Boards, Research Funding.
Improvement of Quality of Response with Ibrutinib Plus Bendamustine/Rituximab Vs Placebo Plus Bendamustine/Rituximab for Previously Treated Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma (CLL/SLL)

Blood | October 12, 2019 | Volume: 126 | Issue: 23 | Pages: 2938-2938

10.1182/blood.v126.23.2938.2938

Abstract Introduction Recent results from the HELIOS phase 3 study in relapsed/refractory CLL/SLL demonstrated that the addition of ibrutinib to chemoimmunotherapy with bendamustine/rituximab (BR) leads to an 80% reduction in risk of progression or death compared with placebo + BR (Chanan-Khan et al. ASCO 2015). In addition to prolongation of progression-free survival (PFS; median not reached vs 13.3 months; hazard ratio: 0.203, 95% confidence interval: 0.150-0.276, p<0.0001), overall response rate (ORR) and rates of complete response (CR) or CR with incomplete marrow recovery (CRi) were significantly improved with ibrutinib + BR (ORR: 82.7% vs 67.8%; CR/CRi: 10.4% vs 2.8%). Here we report additional analyses on the quality of response with ibrutinib combined with BR. Methods In total, 578 patients (pts) with relapsed/refractory CLL/SLL requiring treatment were randomized 1:1 (289 per arm) to receive BR (≤ 6 cycles) with either ibrutinib (420 mg daily) or placebo. Purine analog refractoriness (yes vs no) and number of prior therapies (1 vs > 1) were stratification factors. Pts with deletion 17p (del17p; > 20% of cells) were excluded. All pts were required to have ≥ 1 abnormal lymph node (LN; defined as a measurable lesion > 1.5 cm). The primary end point was independent review committee (IRC)-assessed PFS. In this analysis, individual parameters of response (LN, spleen, overall radiology, absolute lymphocyte count [ALC], complete blood count [CBC], and bone marrow [BM]) were evaluated. Minimal residual disease (MRD) was assessed by flow cytometry using an 8-color panel (Rawstron AC, et al. Leukemia. 2007;21:956-964); MRD samples were collected at confirmation of suspected CR (bone marrow) and every 3 months thereafter (peripheral blood). Rate of MRD-negative response was defined as the proportion of pts who reached negative disease status (< 0.01%, ie, < 1 CLL cell/10,000 leukocytes) in any sample. Reported MRD rates are based on the intent-to-treat (ITT) population. Results The ORR assessed by the IRC was 82.7% with ibrutinib + BR vs 67.8% with placebo + BR (p < 0.0001), and was consistent with ORR reported by the treating physician (investigator assessed) (ORR: 86.2% vs 68.9%, p < 0.0001). However, rates of CR/CRi were higher by investigator assessment (21.4%, ibrutinib + BR vs 5.9%, placebo + BR) than IRC (10.4% vs 2.8%). The IRC employed an independent evaluation of radiological scans including stringent evaluation of LN and volumetric assessment of spleen size-the main reasons for the difference in CR/CRi rates between investigator and IRC assessment. At baseline, similar proportions of pts in each arm had bulky disease defined as LN > 5 cm (54%-58%) or abnormal spleen (~40%) as assessed by IRC. Complete resolution of previous CLL/SLL manifestations as assessed by the IRC was achieved more often in the ibrutinib + BR arm in comparison with placebo + BR for LN (34.6% vs 15.2%), spleen (56.7% vs 37.0%), overall radiology (21.1% vs 9.0%), and BM (19.7% vs 5.9%). Rates of normalization of ALC (> 90%) and CBC (> 70%) were high and similar in the 2 arms. MRD was assessed in 120 pts treated with ibrutinib + BR and 57 pts treated with placebo + BR and was negative in 37 pts and 14 pts, respectively, which corresponds with an MRD-negative response rate of 12.8% vs 4.8% for ibrutinib + BR vs placebo + BR (p = 0.0011). Investigator-determined responses by different levels of MRD are shown in Table 1. The percentage of pts with an MRD level < 1% was higher with ibrutinib + BR vs placebo + BR (32.2% vs 11.8%). Moreover, the percentage of pts with an MRD level < 0.1% was higher for ibrutinib + BR vs placebo + BR (24.6% vs 7.6%) suggesting that the depth of response with ibrutinib + BR was superior. Kaplan-Meier plots by MRD level (Figure 1) show that a lower MRD level was associated with a longer PFS. However, pts in the ibrutinib + BR arm had a more sustained response at every MRD level compared with pts in the placebo + BR arm. Conclusions Pts treated with ibrutinib + BR showed not only a higher ORR, but also a greater depth of response, with more CRs and a higher rate of resolution of LN, spleen, and BM involvement. Furthermore, the rate and depth of MRD negativity was improved, and appeared to last longer in pts treated with ibrutinib + BR compared with pts receiving placebo + BR. With a median follow up of 17 months in the ibrutinib + BR arm, no MRD-negative pts and few MRD-positive pts had progressed, thus evaluating a trend in PFS with MRD negativity is currently limited in this arm. Disclosures Cramer: Gilead: Other: Travel grant, Research Funding; Glaxo Smith Klein/Novartis: Research Funding; Astellas: Other: Travel grant; Mundipharma: Other: Travel grant; Janssen: Other: Travel grant, Research Funding, Speakers Bureau; Hoffman LaRoche: Other: Travel grant, Research Funding, Speakers Bureau. Off Label Use: Combination of bendamustine, obinutuzumab and ibrutinib for treatment of CLL. Fraser:Hoffman LaRoche: Consultancy, Honoraria; Janssen: Honoraria, Research Funding, Speakers Bureau; Celgene: Honoraria, Research Funding. Demirkan:Amgen: Consultancy; Celgene: Other: Travel reimbursement. Santucci Silva:Merck: Research Funding; Celgene: Research Funding; GSK: Research Funding; Janssen: Other: Travel reimbursement, Research Funding; Hoffman LaRoche: Other: Travel reimbursement, Research Funding; Novartis: Other: Travel reimbursement. Janssens:Mundipharma: Speakers Bureau; Roche: Consultancy, Speakers Bureau; Janssen: Consultancy. Goy:Allos, Biogen Idec, Celgene, Genentech, and Millennium. Gilead: Speakers Bureau; Celgene: Consultancy, Research Funding, Speakers Bureau. Mayer:Janssen: Research Funding. Dilhuydy:Roche: Honoraria, Other: Travel reimbursement; Janssen: Honoraria, Other: Travel reimbursement; Mundipharma: Honoraria. Bartlett:Millenium: Research Funding; Medimmune: Research Funding; Novartis: Research Funding; Pfizer: Research Funding; Genentech: Research Funding; ImaginAB: Research Funding; Astra Zeneca: Research Funding; Pharmacyclics: Research Funding; Janssen: Research Funding; Gilead: Consultancy; Seattle Genetics: Consultancy, Research Funding; Celgene: Research Funding. Rule:Roche: Consultancy, Other: Travel reimbursement; J&J: Consultancy, Other: Travel reimbursement, Research Funding; Celgene: Consultancy, Other: Travel reimbursement; Gilead: Research Funding. Sun:Janssen/J&J: Employment, Equity Ownership. Phelps:Janssen/J&J: Employment, Equity Ownership. Mahler:Janssen: Employment, Other: Travel reimbursement. Salman:Janssen/J&J: Employment, Equity Ownership. Schaffer:Janssen: Employment. Balasubramanian:Pharmacyclics LLC, an AbbVie Company: Equity Ownership; Janssen: Employment, Equity Ownership. Howes:Janssen/J&J: Employment, Equity Ownership. Hallek:AbbVie: Honoraria, Other: Speakers Bureau and/or Advisory Boards, Research Funding; Celgene: Honoraria, Other: Speakers Bureau and/or Advisory Boards, Research Funding; Pharmacyclics: Honoraria, Other: Speakers Bureau and/or Advisory Boards, Research Funding; Gilead: Honoraria, Other: Speakers Bureau and/or Advisory Boards, Research Funding; Boehringher Ingelheim: Honoraria, Other: Speakers Bureau and/or Advisory Boards; Roche: Honoraria, Other: Speakers Bureau and/or Advisory Boards, Research Funding; Mundipharma: Honoraria, Other: Speakers Bureau and/or Advisory Boards, Research Funding; Janssen: Honoraria, Other: Speakers Bureau and/or Advisory Boards, Research Funding.
Ibrutinib Monotherapy in Relapsed/Refractory Follicular Lymphoma (FL): Preliminary Results of a Phase 2 Consortium (P2C) Trial

Blood | October 11, 2019 | Volume: 124 | Issue: 21 | Pages: 800-800

10.1182/blood.v124.21.800.800

Abstract Background: Bruton’s tyrosine kinase (BTK) is an essential component of the B-cell receptor signaling pathway, a pathway critical to the survival and proliferation of malignant B cells. Ibrutinib, a small molecule inhibitor of BTK, has shown significant activity in several B-cell malignancies and is currently FDA approved for the treatment of patients (pts) with CLL or mantle cell lymphoma who have received at least one prior treatment.In a Phase 1 dose-escalation study, ibrutinib induced a response in 6 (38%) of 16 patients (pts) with relapsed/refractory FL and 6/11 (54%) of pts treated at doses ≥ 2.5 mg/kg (Advani JCO 2013, Fowler ASH abstr 156:2012). 560 mg daily was identified as a well-tolerated dose in lymphoma resulting in full-target occupancy. On the basis of these results, the Mayo Clinic and Princess Margaret P2Cs conducted a CTEP-sponsored Phase 2 trial of single-agent ibrutinib in relapsed/refractory FL (NCI 9271). Methods: Eligible pts had relapsed or refractory FL (Gr 1, 2, or 3a) that had progressed during or after 1 or more prior chemotherapy regimens. Therapy consisted of ibrutinib, 560 mg daily, until progression or unacceptable toxicity. Response was assessed by CT at 8 weeks and then every 12 weeks. All pts were required to have an on-study biopsy and a second biopsy at progression after response with fresh tissue collected for correlative studies. The primary endpoint was overall response rate (ORR) and secondary endpoints were safety and tolerability, overall survival, time to response, time to treatment failure, duration of response, and progression-free survival (PFS). Planned exploratory correlative studies included C1D8 and C3D1 FDG-PET response evaluation in a subset of 20 patients, and whole-transcriptome sequencing for correlation of mutations with response and resistance. Results: 40 patients (38 evaluable for response) were accrued from April 2013 to April 2014. Median age was 64 years (range 46-82), 70% were men, 55% had FLIPI ≥ 3, median number of prior regimens was 3 (range 1-11), 20% had a prior stem cell transplant, 45% were rituximab refractory, and 36% were refractory to their most recent treatment. At a median follow-up of 6.5 months (mo) (range 1.8-14.6+), the ORR for the 40 intention-to-treat pts is 30% (95% CI: 17-47%) with 1 CR and 11 PRs by CT criteria (4/12 responders had a negative restaging PET/CT). 26 (65%) patients have exhibited tumor size reduction. Only 2/18 (11%) pts with rituximab-refractory disease responded, compared to 8/19 (42%) pts with rituximab-sensitive disease (P=0.06) and 2/3 who were rituximab-naïve. There was no correlation between response and number of prior regimens. Median time to response was 2.4 mo (range 1.8-12.9 mo). Median PFS is 9.9 mo (95% CI: 6 mo, not reached). One of 12 responders has progressed after 9.9 mo on treatment. Median treatment duration was 5 mo (range 1-15+ mo). Dose delays (2 pts) and reductions were infrequent (4 pts). 17 pts have discontinued treatment due to PD (12), refusal (2), AEs (2), and death (1). Gr 3-4 AEs occurred in 30% of pts, including the following AEs in more than 1 pt: anemia (2), neutropenia (3), and infection (2). 3 pts have died (1 PD, 1 pneumonia, 1 gastric hemorrhage). Of the 20 pts with C1D8 PET scans, 19 also had C3D1 PET scans and were evaluable for response. Six of these 19 pts had objective responses by CT criteria at week 8 or beyond. Of the 6 responders, C1D8 PET/CT showed qualitative (visual) improvement in 3 pts, no visual change in 1 pt, and qualitative worsening in 2 pts. On the C3D1 PET/CT, 4 of 6 had qualitative improvement and 2 had no change. Evaluation of quantitative PET data including SUVs and total lesion glycolysis is ongoing and will be presented. Conclusions: Single agent ibrutinib is well tolerated with a modest ORR in relapsed/refractory FL at this early assessment. Continued follow-up is warranted to capture late responders and to establish response duration. Ibrutinib appears less active in FL than in MCL and CLL. Early PET scans (C1D8) do not reliably predict for response. Support by N01-CM-2011-00099 Disclosures Bartlett: Gilead: Consultancy, Research Funding; Seattle Genetics: Consultancy, Research Funding; Astra Zeneca: Research Funding; Janssen: Research Funding; ImaginAb: Research Funding; Genentech: Research Funding; Millennium: Research Funding; Pfizer: Research Funding; Pharmacyclics: Research Funding; Novartis: Research Funding; Medimmune: Research Funding; Celgene: Research Funding. Off Label Use: PF-05082566 for B-NHL. Kuruvilla:Janssen: Honoraria. Reeder:Millennium, Celgene, Novartis: Research Funding.