Witzig, Thomas E.

Abstract Abstract 689 Background: Lenalidomide was demonstrated to have significant single agent activity in relapsed aggressive B cell lymphoma (J Clin Oncol. 2008;26:4952–7, Ann Oncol. 2011;22:1622–7). In a phase I study, we previously demonstrated that Lenalidomide 25 mg day 1–10 of the cycle can be combined with RCHOP21 and this combination does not result in dose delays or increased toxicity (Leukemia 2011;12:1877–81). We now present phase 2 results of R2CHOP in treatment of patients with aggressive B-cell lymphoma. Methods: Eligible patients were adults with newly diagnosed CD20 positive diffuse large B cell (DLBCL) or grade 3 follicular lymphoma (FL). The response was evaluated using PET/CT by standard criteria (J Clin Oncol. 2007;25:579–586). The progression free survival (PFS) was defined as time from diagnosis to disease progression or death. Results: 51 patients - 6 enrolled at the MTD in phase 1 portion of the study and 45 in phase 2 portion were included in the analysis. The median age was 65 years (range, 19–87). 35% of patients were 70 and older. 63% (32/51) were males. 47 patients (92%) had DLBCL and 4 (8%) patients had FL grade 3. The international prognostic index (IPI) was low, low-intermediate, high-intermediate and high in 8 (15%), 18 (35%), 18 (35%) and 7 (14%) patients respectively. 31 patients (60%) had stage 4 disease. Hematological toxicities were: grade 3 and 4 thrombocytopenia (20% and 20% of patients respectively); grade 3 and 4 neutropenia (18% and 71% of patients respectively). Overall 27% of patients experienced a grade 3 or higher non-hematological toxicity at least possibly related to treatment. The most frequent were febrile neutropenia (10%), nausea (4%), urinary tract infection (4%), vascular access complication (4%), and dehydration (4%). 1 patient (2%) developed thrombosis. There was one death (2%) secondary to bowel perforation/sepsis. For 47 patients evaluable for response, the overall response (ORR) and complete response (CR) rates were 98% and 83% respectively. The PFS was 73% at 12 months (Figure). Since the enrolled patients represented a relatively high-risk group (49% intermediate high or high IPI, significant proportion of elderly male patients), the PFS in R2CHOP was compared to PFS in a contemporary cohort of 87 consecutive patients with DLBCL participating in Mayo Clinic Lymphoma Database and treated with standard RCHOP alone. The PFS was 62% at 12 months in this cohort and was inferior to R2CHOP (Figure). Conclusion: Lenalidomide combined with standard R-CHOP21 chemotherapy (R2CHOP) demonstrates predictable safety profile. The ORR and CR rates and PFS are encouraging in elderly high IPI patients, and compared favorably to the R-CHOP treated historical cohort with similar clinical characteristics. A randomized trial will be needed to confirm the benefits of this novel combination. Disclosures: Off Label Use: lenalidomide in treatment of NHL. Reeder:Celgene: Research Funding. Ansell:Seattle Genetics, Inc.: Research Funding; Celgene Corporation: Consultancy.

Abstract Introduction T-cell prolymphocytic leukemia (T-PLL) is a rare mature T-Cell malignancy typically associated with aggressive clinical course. Leukemic T-cells demonstrate post-thymic T-cell phenotypes (Tdt-, CD1a-, CD5+, CD2+ and CD7+) and commonly are CD4+/CD8- T-cells, but co-expression of CD4+/CD8+ or CD8+/CD4- have also been observed. Rearrangement of chromosome 14 involving TCL1 locus is the cornerstone for T-PLL diagnosis which leads to overexpression of oncogene TCL1. As a binding partner for TCL1, AKT expression correlates with worse prognosis. Despite advances in identification of novel mutations, therapeutic option is limited with most patients having very short survival. Herein, we performed a detailed analysis of specific T-cell subsets affected in T-PLL and a comprehensive genomic analysis by whole exome sequencing (WES) and RNA sequencing. We also explored the preclinical efficacy of targeting AKT activation by AKT inhibitor MK2206 on leukemic T-cells isolated from T-PLL patients. Methods T-PLL leukemic cells were isolated from blood or marrow samples of T-PLL patients (n=9) and were tested for involved T-cell subsets by multicolor flow cytometric analysis. Leukemic T-cells were treated with escalating doses of MK2206 (0 to 10 µM) for about 80 hours and were assessed for their apoptosis levels using Annexin V flow cytometric analysis. Whole exome sequencing (WES) and RNA sequencing were conducted using genomic DNA and RNA isolated from purified leukemic T cells from T-PLL patients. Results Phenotypic analysis of T-cell subsets in T-PLL patients showed that leukemic T-cells in 4 untreated T-PLL patients are consistent with naïve T-cell phenotype (CD45RA+, CD45RO-, CCR7+). Leukemic T-cells in 3 of the untreated patients and in 2 of the treated patients have central memory T (CD45RA-, CD45RO+, CCR7+) and effector memory T phenotypes (CD45RA-, CD45RO+,CCR7-) respectively. MK2206 treatment was able to induce dose-dependent apoptosis on the isolated PBMC (containing > 90% leukemic T-cells) of T-PLL patients (n=4) (IC50: 5 µM). FISH analysis found a rearrangement of TCL1 locus on chromosome 14 in all T-PLL cases (n=9). Three cases have also been detected to have del (11q) involving ATM locus and one patient has both del(11q) and del(17p). Subsequent WES (n=7) and RNA sequencing (n=6) analysis revealed recently reported mutations in ATM (frame shift mutation and early stop mutation W579*) in 2 cases, JAK3 (M511I) in 2 cases and STAT5B (T628S and N642H) in 2 cases. Importantly, novel somatic mutations in gene IKZF1 (N159S), NTRK1 (R33W), AP2A2 (P514L), HDAC8 (I115R), RARB (G90W) and TNIP2 (K104Q) were detected by WES. Mutations in EML4 (L548W and F304S) and VAV3 (C282Y and splice site mutation) were also identified in 2 different T-PLL cases. RNA sequencing revealed several fusion transcripts resulting in early stop of several different genes including PTPRT, L3MBTL1, UCKL1 in one T-PLL case. Conclusion T-PLL leukemic T-cells are consistent with either naïve or central memory T-cell subsets in untreated patients. The AKT inhibitor MK-2206 was capable of inducing apoptosis and could be a potential therapeutic agent for T-PLL patients. In addition, we detected known mutations in ATM and JAK-STAT pathways. Novel mutations in genes involving DNA binding and chromatin remodeling (IKZF1, HDAC8) or kinase signal pathway (NTRK1, TNIP2, VAV3, EML4) were uncovered. These results suggest that further therapeutic approaches could be developed to target DNA binding factors or JAK-STAT or AKT-TCL1 signal pathway with an ultimate goal to improve survival of T-PLL patients. Disclosures Off Label Use: Off label use of MK2206: MK-2206 is an AKT inhibitor obtained from Selleck Chemicals and is used to treat leukemic cells in vitro to test the leukemic sensitivity to AKT inhibition. .

Abstract Abstract 3661 Objective: We conducted this trial to determine the maximum tolerated dose (MTD) and schedule of temsirolimus added to an established regimen comprised of rituximab and cladribine for the initial treatment of mantle cell lymphoma and to generate preliminary information on the toxicity and efficacy of this combination. Methods: A standard phase I cohort of 3 study design was utilized. MTD was defined as the dose level below the lowest dose that induces dose-limiting toxicity (DLT) in at least one-third of patients (at least 2 of a maximum of 6 new patients). DLT was defined as grade 4 ANC (<500) for ≥5 days, grade 4 ANC (<500) associated with fever (>100.5 F) and/or active infection, PLT <25,000, grade 4 infection, or ≥grade 3 non-hematologic toxicity during the first cycle of therapy as per NCI Common Terminology Criteria for Adverse Events v3.0. The fixed doses of rituximab and cladribine were 375 mg/m2 IV day 1 and 5 mg/m2/d IV days 1–5 of a 28 day cycle, respectively, as previously published. There were 5 planned temsirolimus IV dose levels: 15 mg day 1; 25 mg day 1; 25 mg days 1 and 15; 25 mg days 1,8 and 15; and 25 mg days 1,8,15, and 22. The fifth dose level is as previously published in combination with rituximab. Results: A total of 17 patients were treated: 3 each at dose levels 1–4 and 5 at dose level 5 (25 mg temsirolimus days 1,8,15, and 22). The median age was 75 years (52–86). There were 11 males and 6 females. At presentation 88% had stage IV disease, and 94% had extranodal disease. MIPI scores were low in 6% (1 patient), intermediate in 59% (10 patients), and high in 35% (6 patients). There was a single DLT recorded at dose level 3 based on the initial DLT criteria, though this cytokine release syndrome was clearly rituximab related, and occurred prior to the first dose of temsirolimus. Five patients were treated at the highest planned temsirolimus dose level (25 mg days 1,8,15, and 22) with no DLT observed. No further dose escalation was planned, and this level was determined to be tolerated, though higher levels may be tolerable. All patients were evaluable for adverse events. Hematologic toxicity was frequent, with grade 3 anemia in 12% of patients, grade 3 thrombocytopenia in 35%, grade 4 thrombocytopenia in 30%, grade 4 lymphopenia in 47%, grade 3 neutropenia in 24%, and grade 4 neutropenia in 18% of patients. There were 3 thrombotic episodes, 2 of which were attributed to therapy, and 3 episodes of pneumonitis. The overall response rate was 94% with 53% CR and 41% PR. The median progression free survival was 18.7 months. Conclusions: Temsirolimus 25 mg IV weekly may be safely added to rituximab and cladribine at 375 mg/m2 IV day 1 and 5 mg/m2/d IV days 1–5 of a 28 day cycle, respectively. This regimen had promising preliminary activity in an elderly cohort of patients with mantle cell lymphoma. Disclosures: Off Label Use: Temsirolimus for mantle cell lymphoma.

Abstract Abstract 905 Introduction: Though dose-intensive strategies using chemoimmunotherapy have significantly improved mantle cell lymphoma (MCL) outcomes with prolonged progression-free survival (PFS), most patients still relapse over time. In the relapsed setting, MCL patients often develop chemoresistance and have a poor overall prognosis. The immunomodulatory agent lenalidomide has demonstrated tumoricidal and antiproliferative effects in MCL and clinical activity and safety in multiple phase II studies in aggressive non-Hodgkin's lymphoma. The objective of the MCL-001 “EMERGE” study was to examine the safety and efficacy of single-agent lenalidomide in subjects with MCL who relapsed or were refractory to bortezomib. Methods: This phase II, multicenter, single-arm, open-label study examined single-agent lenalidomide administered at 25 mg/d PO on days 1–21 of a 28-day cycle until disease progression, unacceptable toxicity, or voluntary withdrawal. The subjects were required to have had prior treatment with rituximab, cyclophosphamide and anthracycline (or mitoxantrone), and to have relapsed or progressed (<12 months) after or were refractory to bortezomib. The primary endpoints were overall response rate (ORR) and duration of response (DOR); secondary endpoints included complete response (CR), PFS, time to progression (TTP), overall survival (OS) and safety. Efficacy data were measured by investigators and an independent central review committee according to modified International Working Group criteria and analyzed by SAS. Results: 134 subjects with relapsed or refractory MCL who were heavily pretreated (no limitation in number of prior therapies) were enrolled. The median age was 67 y (range, 43–83), two-thirds of them being 65 y or older and 93% with advanced stage disease (stage III-IV). The median number of prior therapies was 4 (range, 2– 10) with 78% of subjects having received ≥ 3 prior lines of treatment. The ORR to single-agent lenalidomide was 28% (CR/CRu 8%; Table 1) by independent central review, with a median DOR of 16.6 mo (95% CI, 7.7–26.7; Figure 1). The ORR was 32% (CR/CRu 16%) by investigator assessment, with a median DOR of 18.5 mo. Median time to response (central review) was 2.2 mo (3.7 mo to achieve CR). The median PFS was 4.0 mo (95% CI, 3.6–5.6); median OS was 19.0 mo (95% CI, 12.5–23.9). Subjects received an average dose of 20 mg/d of lenalidomide. Lenalidomide was dose reduced in 38% of subjects; treatment discontinuation due to an adverse event (AE; primarily myelosuppression) was reported in 19% of subjects. The most common grade 3/4 AEs were neutropenia (43%), thrombocytopenia (28%), anemia (11%), pneumonia (8%) and fatigue (7%). Other AEs (any grade) included tumor flare reaction (13 subjects, 10%), deep vein thrombosis (5 subjects, 4%), pulmonary embolism (3 subjects, 2%) and invasive second primary malignancies (3 subjects, 2%). Conclusions: The EMERGE study demonstrated rapid and durable efficacy of lenalidomide in MCL subjects who relapsed or progressed after or were refractory to bortezomib. These results in heavily pretreated MCL subjects (median of 4 prior treatments), and with an expected toxicity profile support single-agent lenalidomide in subjects with relapsed or refractory MCL after bortezomib. Disclosures: Goy: Pfizer: Advisory board member, Advisory board member Other; Seattle Genetics: Advisory board member Other; J&J: Advisory board member, Advisory board member Other; Pharmacyclics: Advisory board member, Advisory board member Other; Millenium: Advisory board member, Advisory board member Other, Speakers Bureau; Celgene: Advisory board member Other. Off Label Use: This is a phase 2 clinical study of safety and efficacy for lenalidomide in patients with MCL. Sinha:Celgene: Research Funding. Williams:Celgene: Clincial Trial Research Support, Advisory Boards, Data Safety Committee Member, Consultant Other, Consultancy. Drach:Celgene: Speakers Bureau; Janssen: Speakers Bureau; Roche: Research Funding. Ramchandren:Seattle Genetics: Speakers Bureau. Herbrecht:Pfizer: Advisory board member Other. Zhang:Celgene: Employment. Cicero:Celgene: Employment. Fu:Celgene: Employment. Witzig:Celgene : Research Funding.

Abstract Abstract 925 Diffuse large B-cell lymphomas (DLBCL) consists of biologically distinct subtypes: Germinal Center B-cell (GCB)–like and Activated B-cell (ABC)-like. Studies to date suggest that patients with tumors that have ABC features have an inferior survival; therefore, it is important to develop new therapies specifically for ABC-type DLBCL based on mechanistic differences. It has been shown that the ABC-DLBCL has high levels of total and phosphorylated STAT3 (pSTAT3) protein and this STAT3 activity may play a role in the survival of ABC-DLBCL cells. Indeed, when ABC and GCB cell were incubated with the novel JAK2 inhibitor TG101348 (TargeGen, San Diego, CA) we found potent cytotoxicity (LD50 2μM) in ABC DLBCL but not in GCB DLBCL. This provides further rationale to study the regulation of STAT3 in the survival of ABC type DLBCL cells. In studies of HDAC expression in ABC DLBCL cells, we found over-expression of the class 1 histone deacetylases, specifically HDAC1 and HDAC3. We then performed co-immunoprecipitation experiments to learn the functional interaction between STAT3 and HDACs. We found that STAT3 formed complexes with HDAC1 to a greater extent than HDAC3. We also showed that STAT3 did co-precipitate with HDAC1 suggesting a reciprocal relationship between these two proteins. These results suggested that HDAC1 (but not HDAC3) might be involved in the regulation of STAT3. The HDAC inhibitor LBH589 (LBH, Novartis Pharm) was more cytotoxic to ABC (LD50, 10-20nM) than GCB (LD50, 50-100nM) and was shown to dephosphorylate STAT3. These results led to experiments designed to determine the effect of LBH on STAT3 acetylation. When ABC cells were incubated with LBH, co-immunoprecipitation data showed a dose-dependent increased in acetylation of STAT3 without significant change on the levels of STAT3 immunoprecipitated. Next, we asked that how LBH is dephosphorylating STAT3. One potential mechanism is activation of a protein phosphatase. Immunoprecipitation of protein phosphatase 2A (PP2A) in the lysates of LBH-treated cells followed by western blotting of STAT3 demonstrated a positive correlation between LBH dose and amount of STAT3 co-immunoprecipitated with PP2A. Our data show that when LBH is incubated with ABC cells, the LBH increases binding of PP2A to STAT3 and the increased phosphatase activity turns off STAT3 signaling. Since both HDAC inhibitor (LBH) and the JAK2 inhibitor (TG) had selective cytotoxic effects on ABC cells, and since both agents dephosphorylate STAT3, we combined the two drugs. We found that the combination exhibited enhanced inhibitory effects on the growth of ABC cells and was able to alter the association of STAT3 with HDAC1 and subsequently dephosphorylate STAT3 to greater extent than either agent alone. Furthermore, we knocked down HDAC1 expression (through siRNA) in OCILy10 (ABC) cells and showed that inhibition of HDAC1 inhibits constitutively activated STAT3. This data suggests that inhibiting HDAC1 expression results in STAT3 dephosphorylation. In summary, we have demonstrated that a key consequence of HDAC expression in ABC cells is continuous activation of STAT3. These data indicate that HDACs activate STAT3 and that PP2A may be important in maintaining STAT3 in the activated state in the ABC cells. This study describes a new mechanism by which STAT3 mediates ABC cell survival and provides the rationale for targeting ABC type DLBCL by simultaneously inhibiting HDAC activity and STAT3 activation by pharmacologic grade inhibitors such as LBH589 and TG101348, which are currently in clinical trial. A phase 1 and 2 trial of JAK2 inhibitor, TG101348 for ABC/GCB type DLBCL is planned. Disclosures: No relevant conflicts of interest to declare.

Abstract Abstract 2668 Poster Board II-644 Interleukin-12 (IL-12) has been demonstrated to induce IFN-g production by T and NK cells and thereby contribute to anti-tumor immunity. However, the administration of IL-12 to boost anti-tumor immunity in B-cell lymphoma has shown no clinical benefit. In fact, clinical trials of IL-12 in combination with rituximab in follicular B-cell lymphoma (FL) showed a lower response rate in patients treated with the combination than in patients treated with rituximab alone (Clin Cancer Res. 2006 15; 12:6056-63). The goal of this study was therefore to determine the role of IL-12 in the antitumor response in B-cell NHL. First, we measured serum levels of IL-12 in patients with untreated FL before treatment with rituximab and normal healthy controls. We found that serum IL-12 levels were elevated in FL patients compared to healthy individuals (median: 0.50 ng/ml, n=30 vs 0.32 ng/ml, n=22; p= 0.03) and that elevated serum IL-12 levels were associated with a poor outcome in these patients when treated with rituximab alone as initial therapy. Using 0.56 ng/ml as a cutoff, patients with serum IL-12 levels of greater than 0.56 ng/ml had a significantly shorter time to progression than patients with IL-12 levels less than 0.56 ng/ml (12 months versus 40 months; p=0.001). To determine the mechanism by which IL-12 may contribute to a poor prognosis, we investigated the role of IL-12 on induction of immune tolerance. First, we found that TIM-3, a member of the T cell immunoglobulin and mucin domain-containing protein (TIM) family that functions to terminate TH1-mediated immunity and promote tolerance, was constitutively expressed on a subset of intratumoral T cells accounting for approximately 15% and 25% of the intratumoral CD4+ and CD8+ T cells, respectively. In contrast, less than 2% of T cells from peripheral blood of normal individuals expressed TIM-3. TIM-3-expressing T cells were distinct from regulatory T cells since CD25+ and Foxp3+ T cells lacked TIM-3 expression. Secondly, we found that TIM-3-expressing CD4+ cells were unable to produce cytokines such as IL-2, IFN-g or IL-17 and that TIM-3-expressing CD8+ T cells failed to produce Granzyme B, IFN-g or IL-2. We also observed that TIM-3-expressing T cells lost the capacity to proliferate in response to TCR activation. These results suggest that TIM-3 expressing CD4+ and CD8+ T cells are functionally exhausted. Thirdly, we observed that TIM-3 expression on T cells could be induced by activation and that IL-12 was the strongest stimulus to induce TIM-3 expression on CD4+ and CD8+ T cells. Finally, we found by immunohistochemistry (IHC) that Galectin-9 (Gal-9), a ligand for TIM-3, was abundantly expressed on lymphoma B cells. In vitro incubation with a stable form of Gal-9 induced apoptosis of CD4+ and CD8+ T cells in a dose dependent fashion. Gal-9-mediated apoptosis of T cells was attenuated by a TIM-3 Fc protein and isolated TIM-3+ T cells exhibited a significantly higher apoptosis rate than TIM-3− T cells in response to Gal-9. These results indicate that, in contrast to the observations in vitro or in vivo in mice, IL-12 actually plays a detrimental role in lymphoma patients. Given the findings that IL-12 strongly induces TIM-3 expression on effector T cells and that the TIM-3/Gal-9 pathway impairs the immune response, we conclude that increased serum levels of IL-12 suppress anti-tumor immunity in follicular lymphoma patients and is associated with a poor prognosis. Disclosures: Witzig: Novartis: Research Funding.

Abstract Abstract 684 Background. Obesity has been associated with an increased risk of developing of lymphoma, particularly DLBCL. Genetic variation in several energy balance genes, including leptin (LEP), its receptor LEPR, ghrelin (GHRL) and neuropeptide Y (NPY) have been shown to modulate risk of lymphoma, although their impact on survival is not known. In contrast, recent studies suggest that patients either overweight (Body Mass Index (BMI), 25 to<30 kg/m2) or obese (≥30 kg/m2) may have a superior prognosis in DLBCL, although its impact in FL and in the current treatment era is not known. We evaluated the association of BMI at the time of diagnosis, 2 years prior to diagnosis and at ages 18, 35 and 50 years, along with germline genetic variation in selected energy balance genes with event-free (EFS) and overall (OS) survival in DLBCL and FL. Methods. We evaluated these associations in a prospective cohort of newly diagnosed DLBCL (N=764) and FL (N=649) patients enrolled at the Mayo Clinic and University of Iowa from 2002–2009 as part of the Molecular Epidemiology Resource. Peripheral blood DNA, clinical data and self-reported historical weights were collected at enrollment. Patients received standard disease treatment strategies, and were systematically followed for disease progression, re-treatment, and death. Single nucleotide polymorphisms (SNPs) were genotyped as part of a custom Illumina iSelect panel. The most prevalent homozygous genotype was used as the reference group, and each SNP was modeled as having a log-additive effect in the regression model. Cox proportional hazards regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CI) for the association of the obesity measures and SNPs with outcome, adjusted for treatment class and subtype specific prognostic factors (IPI, FLIPI). Results. For DLBCL patients (median age 63 years, range 18–92) the median follow-up was 47 months (range 0–101); 58% had an IPI 0–1 risk disease; and 87% received immunochemotherapy. For FL patients (median age 60 years, range 25–94), the median follow-up was 60 months (range 11–110); 24% had FLIPI score 3–5; and main initial treatments were observation (32%), rituximab (R)-monotherapy (12%), CVP +/−R (19%), and anthracycline +/−R (22%). The main results for BMI and prognosis are reported in the Table. For DLBCL, obese patients at diagnosis had better EFS and OS; this association was weaker for BMI at age 50 and 35 years. In contrast, for FL, overweight and obese patients at diagnosis had a poorer EFS and OS, and this was also observed for BMIs two years before diagnosis and at ages 50 and 35 years. In FL, the LEP SNP rs2167270 was associated with inferior EFS (HR=1.25; 95%CI 1.05–1.49) and OS (HR=1.28; 95%CI 0.90–1.83). The NPYSNP rs16147 was associated with inferior FL OS (HR=1.50; 95%CI 1.03–2.17) but was not associated with EFS. None of the energy balance and metabolism SNPs were associated with DLBCL EFS or OS. Conclusions. Higher BMI prior to and at diagnosis, as well as SNPs in LEP and NPY,were significantly associated with FL prognosis, with inferior outcomes in overweight and obese patients. These novel findings in the modern treatment era suggest an important role of obesity pathways in FL prognosis. In DLBCL, we confirm the recent findings of improved survival in DLBCL in obese patients, and extend this to the modern treatment era and BMI earlier in life. Disclosures: No relevant conflicts of interest to declare.

Abstract Abstract 1669 Poster Board I-695 Background The addition of rituximab to chemotherapy significantly improved the results of therapy in aggressive non-Hodgkin's B cell lymphoma (NHL). However, significant number of the patients relapse following initial therapy. Lenalidomide was shown to have significant single agent activity in relapsed aggressive B cell lymphoma (J Clin Oncol 26:4952-7, 2008) however the safety in combination with standard first line immunochemotherapy is unknown. We initiated a phase I/II trial of R2-CHOP (cyclophosphamide, vincristine, doxorubicin, prednisone rituximab and lenalidomide) to establish the safety and efficacy of this therapy in the treatment of patients with newly diagnosed aggressive B cell NHL. Herein, we report the results of phase I portion of this study. Methods A phase I study was designed to define the maximum tolerated dose (MTD) of lenalidomide administered on days 1-10 with R-CHOP chemotherapy (rituximab 375 mg/m2, cyclophosphamide 750 mg/m2, doxorubicin 50mg/m2, vincristine 1.4 mg/m2, all on day 1, prednisone 100 mg/m2 days 1-5 of 21 day cycle) utilizing 3+3 dose escalation design. Lenalidomide dose escalation levels were 15 mg, 20 mg and 25 mg. All patients received 6 mg pegfilgrastim injection on day 2. Dose limiting toxicity (DLT) was defined as any grade 3 or more non-hematological toxicity or a hematological toxicity requiring a delay of the next cycle of chemotherapy due to cytopenia. The latter criterion was to ensure maintenance of the dose intensity and schedule of RCHOP; a potentially curative therapy in this setting. Eligible patients were adults newly diagnosed with CD20 positive diffuse large cell or follicular grade III B cell lymphoma, ECOG PS 0-2 and good organ function. There was no upper age restriction to participate in this study. Results Twelve patients were enrolled in phase I of this study. The median age was 69 years (range, 49-82) and 58% (7/12) of patients were males. Ten patients (83%) had DLBCL and two (17%) patients had follicular grade 3B lymphoma. International prognostic index was intermediate, high- intermediate and high in 6, 4 and 2 patients respectively. Patients distribution by lenalidomide dose was: 3 patients received 15 mg/day, 3 received 20 mg/day and 6 received 25 mg/day on days 1-10. Non-hematological toxicities included: grade 3 toxicity - neuropathy in one patient (8.3%), grade 2 toxicities were: infection in 17% (2/12) patients (skin in one patient, otitis media, and urinary tract infection in one patient); nausea 8% (1/12), rash 8% (1/12) and alopecia 41% (5/12). The most common toxicity to R2-CHOP was myelosuppresion. Grade 3 and 4 neutropenia occurred in 17% (2/12) and 41% (5/12) of patients, respectively. The neutropenia was of short duration, and no patients developed neutropenic complications. Grade 3 thrombocytopenia was seen in 8% (1/12). Most importantly, there were no delays in chemotherapy due to cytopenias. No DLT was seen. The 25 mg/day days 1-10 dose of lenalidomide was taken forward to an ongoing phase 2 trial. Conclusion Lenalidomide at a dose of 25 mg/day for days 1- 10 combined with R-CHOP chemotherapy is well tolerated. The addition of lenalidomide did not affect hematological recovery and did not result in treatment delays. This dose and schedule is now being evaluated in the phase II part of the trial. Disclosures Zent: Genentech, Bayer, Genzyme, Novartis: Research Funding. Witzig:Novartis: Research Funding.

Abstract Abstract 443 Background: MYC translocations have been reported to have inferior outcome in aggressive non-Hodgkin lymphomas. Here we present MYC translocation prevalence and outcome from two cohorts of newly diagnosed diffuse large B-cell lymphoma (DLBCL) patients treated in the chemotherapy (C) and immunochemotherapy (IC) eras. Methods: Tissue microarrays were created from 302 newly diagnosed DLBCL patients evaluated at the Mayo Clinic with availabel paraffin tissue. 233 DLBCL patients first diagnosed from March 1986-July 2001 were retrospectively identified based on a diagnosis of DLBCL and treatment with anthracycline-based chemotherapy. 69 DLBCL patients diagnosed from March 2002-October 2005 and treated with immunochemotherapy were prospectively enrolled in the University of Iowa / Mayo Clinic Lymphoma SPORE Molecular Epidemiology Resource. Central pathology review was performed on all samples to confirm the diagnosis of DLBCL. Interphase FISH was performed using a breakapart strategy for MYC and BCL6 gene regions and a dual fusion strategy for t(14;18)(IGH&/BCL2). Results: Chemotherapy (C) era patients were primarily treated with CHOP (88%); immunochemotherapy (IC) era patients were all treated with an R-CHOP based regimen. The median age at diagnosis was 65 years (range, 22-92) for C patients and 65 years (range, 20-82) for IC patients. Median follow-up for C patients was 11.3 years (range, 2.7-21.3) with 145 (62%) deaths; for IC patients, the median follow-up was 5.0 years (range, 2.1-6.4) with 17 deaths (25%). FISH was successful in 195 of 302 patients (65%). MYC translocations were identified in 6 of 141 C patients (4%) and 3 of 54 IC patients (6%). MYC translocations were associated with inferior overall survival in the C patients (p=0.001), the IC patients (p=0.04), and in the combined group (p≤0.001). Median survival of patients with MYC translocations was 19 months and 16 months for C and IC respectively, compared to 112 months (C) and unreached (IC) for DLBCL patients without MYC translocations. 4 of the 9 MYC translocation patients had a double hit (2 with both MYC and BCL2 translocations and 2 with translocations of MYC, BCL2, and BCL6). Associations of MYC and outcome remained significant in all patients after adjusting for treatment and IPI (p<0.05). Conclusions: MYC translocations are present in approximately 5% of DLBCL patients and are associated with poor outcome in patients treated with C or IC. New treatment approaches are needed for DLBCL patients with MYC translocations. Disclosures: No relevant conflicts of interest to declare.

Abstract Abstract 1676 Poster Board I-702 Introduction Aggressive NHL (a-NHL) comprises a heterogeneous group of B-cell malignancies, each characterized by a unique histology and molecular markers. The most common types are diffuse large B-cell lymphoma (DLBCL), transformed lymphoma (TL), follicular grade III (FL-III), and mantle cell lymphoma (MCL). Although initial therapy can be effective, up to 40% of patients with DLBCL either fail to respond or relapse after initial therapy (Habermann TM et al JCO 2006), and relapses are likely among patients with MCL. For such patients survival outcomes are particularly poor with few effective treatment options available. Lenalidomide (Revlimid®), an immunomodulatory agent with anti-proliferative as well as apoptotic activity was tested in a pilot study and demonstrated a 35% overall response rate (ORR) with a median duration of response (DR) of 10.4 months (Wiernik et al 2008 EHA. Abst: 764). Based on these encouraging data, we performed a large, international, confirmatory phase 2 study to assess the safety and efficacy of single-agent lenalidomide in patients with relapsed of refractory DLBCL or MCL (CC-5013-NHL-003). Methods Patients were required to have relapsed or refractory aggressive B-cell NHL after ≥1 prior therapies and have at least one measurable lesion '2 cm. Patients received oral lenalidomide 25 mg once daily on days 1–21 of a 28-day cycle, and continued therapy until disease progression or unacceptable toxicity. Results 217 patients were enrolled and received lenalidomide with 108 (50%) DLBCL, 57 (26%) MCL, 19 (9%) FL-III, and 33 (15%) TL (Table 1). The median age was 66 yrs (range, 21–87), 97 patients (45%) had intermediate (3) or high (4–5) IPI scores, and the median time from diagnosis was 2.7 yrs (range, 0.04–20.6). Patients had received a median of 3 prior therapies (range, 1–13), and rituximab was included as a part of the prior therapy in 94% (205/217) of patients. The ORR for all 217 patients was 35% (77/217), with 13% (29/217) complete response (CR)/unconfirmed CR (CRu), 22% (48/217) partial response (PR), and 21% (46/217) with stable disease (SD). Responses were observed in all histological types (Table 1). Patients with a prior stem cell transplantation had a 37% ORR (27/73). The ORR was 28% (27/95) in those patients who were refractory to their last therapy, and 33% (38/116) in patients who were rituximab refractory (defined as <6 months response or no response). Median progression-free survival (PFS) for all patients was 3.5 months (95% CI, 2.5, 4.4) and the median DR for the 77 responders was 11.6 months (95% CI, 6.2, not reached [NR]). The primary side effect of lenalidomide was reversible myelosuppression. Grades 3 or 4 neutropenia occurred in 41%, thrombocytopenia in 19%, anemia in 9%, and leucopenia in 7% of patients. Adverse events caused dose reductions or interruptions in 44% (96/217) of patients and led to treatment discontinuation in 22% (48/217). Conclusion This international study supports earlier pilot-study results showing that lenalidomide has promising anti-tumor activity in aggressive B-cell NHL, with a predictable and treatable toxicity profile. These data warrant further evaluation of lenalidomide in combination with other regimens in the treatment of each histological subtype, and further exploration of lenalidomide in the maintenance setting. Disclosures Witzig: Celgene: Research Funding. Off Label Use: Lenalidomide in relapsed/refractory aggressive NHL. Vose:Celgene: Research Funding. Zinzani:Celgene: Research Funding. Guo:Celgene: Employment, Equity Ownership. Pietronigro:Celgene: Employment, Equity Ownership. Ervin-Haynes:Celgene: Employment. Czuczman:Celgene: Research Funding.