ALBERT

Description: Abstract 3955 Background: Patients (pts) with relapsed diffuse large B-cell lymphoma (DLBCL) ineligible for autologous stem cell transplant (ASCT) or relapsing after ASCT have a poor prognosis and limited therapeutic options. New treatment options are needed for these pts. Ofatumumab is a human monoclonal antibody that targets a membrane-proximal epitope comprising both the large loop and small loop of CD20, and has shown effective lysis of chemotherapy-refractory DLBCL cells in vitro (Teeling et al. Blood 2004; Cillessen et al. Blood 2007; abstract 2346). We report the first results from an open-label, single-arm, international Phase II trial that evaluated ofatumumab monotherapy in relapsed or progressive DLBCL. Methods: Pts (age ≥18 years) with relapsed or progressive CD20+ DLBCL ineligible for ASCT or with relapsed or progressive disease after ASCT were enrolled between December 2007 and August 2009 (N=81). Relapsed or progressive disease was defined as relapse after a complete remission (CR) or disease progression after partial remission (PR). Pts received 8 weekly infusions of ofatumumab (dose 1, 300 mg; doses 2–8, 1000 mg). The primary endpoint was overall response rate (ORR) evaluated during the 6 months from the start of treatment, as assessed by an Independent Endpoint Review Committee according to the revised response criteria (Cheson et al. J Clin Oncol 2007). Secondary endpoints included duration of response, progression-free survival (PFS), overall survival (OS) and safety. Results: Baseline characteristics are shown in the Table. Pts were heavily pretreated (median 3 prior systemic therapies), and 32% of pts did not respond to their last prior therapy. Nearly all pts (96%) had received prior rituximab-containing treatment; 54% had received 2 or more courses of prior rituximab therapy (Table). Overall, 58% of pts completed all 8 infusions of ofatumumab, 65% received at least 6 infusions, and 81% received at least 4 infusions. The primary reason for treatment discontinuation was disease progression. The ORR (95% CI) was 11% (4–18%), including 3 CRs (4%) and 6 PRs (7%). Of these 9 responding pts, 8 had responded to their last systemic therapy. The median duration of response (95% CI) was 6.9 months (5.3–6.9) and median PFS (95% CI) was 2.5 months (2.3–2.9). Infusion-related events occurred in 59% of pts, primarily occurred during infusion 1 (40% of pts) and infusion 2 (22%), and subsided during subsequent infusions; these events were predominantly grade 1–2 in severity (96% of pts). The most common (〉10% of pts) adverse events (AEs; any grade) were diarrhea (17%), fatigue (15%), peripheral edema (15%), neutropenia (14%), abdominal pain (12%), constipation (12%), nausea (12%), pyrexia (11%), anemia (11%) and leukopenia (11%). Of these, ≥ grade 3 events included neutropenia (10%), leukopenia (6%), anemia (5%) and fatigue (1%). Grade 3 or greater thrombocytopenia and febrile neutropenia were reported in 6% and 4% of pts, respectively. The most common infectious events were upper respiratory tract infections (7% of pts), all of which were grade 1–2 events. In total, 13 pts died during the study; 3 pts died during the treatment period and 10 pts died during post-treatment follow up (until 24 months from study start). Deaths were due to disease progression (n=10), sepsis (n=1), circulatory collapse (no further details; n=1) and multi-organ failure (n=1). Conclusions: Single-agent ofatumumab was well tolerated with an ORR of 11% in heavily pretreated pts with relapsed or progressive DLBCL, nearly all of whom had received prior rituximab therapy. Response to last systemic treatment appeared to influence response to ofatumumab in this pt population. Further studies of ofatumumab in combination with chemotherapy in relapsed DLBCL are currently underway. Disclosures: Off Label Use: Ofatumumab is an investigational anti-CD20 monoclonal antibody, currently under development for the treatment of B-cell malignancies (chronic lymphocytic leukemia, diffuse large B-cell lymphoma, Waldenstroms macroglobulinemia and follicular lymphoma) as well as autoimmune diseases (rheumatoid arthritis and multiple sclerosis). Davies:GlaxoSmithKline: Consultancy, Membership on an entity's Board of Directors or advisory committees. Padmanabhan:GlaxoSmithKline: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. Gupta:GlaxoSmithKline: Employment. Lin:GlaxoSmithKline: Consultancy, Employment. Davis:GlaxoSmithKline: Consultancy, Membership on an entity's Board of Directors or advisory committees. Losic:Genmab A/S: Employment, Equity Ownership. Lisby:Genmab A/S: Employment. Radford:GlaxoSmithKline: Equity Ownership; Genmab: Consultancy, Honoraria.

Description: We conducted an international phase 2 trial to evaluate 2 dose levels of ofatumumab, a human CD20 mAb, combined with fludarabine and cyclophosphamide (O-FC) as frontline therapy for chronic lymphocytic leukemia (CLL). Patients with active CLL were randomized to ofatumumab 500 mg (n = 31) or 1000 mg (n = 30) day 1, with fludarabine 25 mg/m2 and cyclophosphamide 250 mg/m2 days 2-4, course 1; days 1-3, courses 2-6; every 4 weeks for 6 courses. The first ofatumumab dose was 300 mg for both cohorts. The median age was 56 years; 13% of patients had a 17p deletion; 64% had β2-microglobulin 〉 3.5 mg/L. Based on the 1996 National Cancer Institute Working Group (NCI-WG) guidelines, the complete response (CR) rate as assessed by an independent review committee was 32% for the 500-mg and 50% for the 1000-mg cohort; the overall response (OR) rate was 77% and 73%, respectively. Based on univariable regression analyses, β2-microglobulin and the number of O-FC courses were significantly correlated (P 〈 .05) with CR and OR rates and progression-free survival (PFS). The most frequent Common Terminology Criteria (CTC) grade 3-4 investigator-reported adverse events were neutropenia (48%), thrombocytopenia (15%), anemia (13%), and infection (8%). O-FC is active and safe in treatment-naive patients with CLL, including high-risk patients. This trial was registered at www.clinicaltrials.gov as NCT00410163.

Description: Ofatumumab, the human CD20 monoclonal antibody that binds a distinct epitope from rituximab, has demonstrated clinical benefit as monotherapy for patients with chronic lymphocytic leukemia refractory to fludarabine and alemtuzumab (FA-ref) and patients refractory to fludarabine with bulky (〉 5 cm) lymph nodes (BF-ref). To potentially gain insight into outcomes in patients previously treated with or refractory to rituximab, we performed an ad hoc retrospective analysis in the final 96 FA-ref and 111 BF-ref patients. There were 117 patients previously treated with rituximab (98 rituximab-refractory); 89 patients were rituximab-naive. For rituximab-treated, rituximab-refractory, and rituximab-naive patients, overall response rate was 43%, 44%, and 53%; median progression-free survival was 5.3, 5.5, and 5.6 months; and median overall survival was 15.5, 15.5, and 20.2 months. There were no significant differences in ofatumumab-related infusion reactions, or hematologic or infectious adverse events between subgroups. In summary, ofatumumab monotherapy was effective and well tolerated in patients with fludarabine-refractory chronic lymphocytic leukemia, including in patients with previous rituximab exposure. This trial was registered at www.clinicaltrials.gov as #NCT00349349.

Description: Introduction: IDH2 mutations (mIDH2) are recurrent in ~5% of patients (pts) with MDS and ~15% of pts with acute myeloid leukemia (AML). mIDH2 proteins have neomorphic enzymatic activity and are associated with DNA and histone hypermethylation, altered gene expression, and blocked differentiation of hematopoietic progenitor cells. Enasidenib (AG-221/CC-90007) is a small-molecule allosteric inhibitor of mIDH2 protein that induces hematological responses in pts with mIDH2 AML, including relapsed or refractory (R/R) AML (Stein, Clin Cancer Res, 2016). The current analysis is the first to evaluate the safety and clinical efficacy of enasidenib monotherapy in pts with mIDH2-positive MDS. Methods: This analysis includes pts ages ≥18 years with MDS and mIDH2 who participated in a phase 1 study with a dose-finding period followed by an expansion phase in which all pts received daily oral enasidenib 100 mg QD in 28-day cycles. Pts had R/R MDS or were not candidates for standard therapies. Response was measured using peripheral blood (PB) and bone marrow (BM) samples from days 15, 29, 57, and every 56 days thereafter, and by objective investigator report. Overall response rate (ORR) reflects the best response achieved by pts, and includes complete remission (CR), partial remission (PR), marrow CR (mCR), and any hematologic improvement (HI) (IWG 2006 MDS criteria). Evaluable pts required a response assessment at Cycle 2 Day 1 or later, or discontinued before assessment. Overall survival (OS) was estimated using Kaplan-Meier methods. Next-generation sequencing identified pre-existing co-occurring genomic alterations using the FoundationOne® Heme test on purified mononuclear cells from BM or PB, to assess relationships between co-mutational status and clinical response. Results: Of 16 pts with MDS in this study, 12 pts had discontinued and 4 pts continued to receive enasidenib at interim database lock (15 April 2016). Reasons for discontinuation included disease progression (n=1), adverse event (AE; n=1), death (n=4), investigator decision (n=2), and other (n=1); 3 pts proceeded to transplant. Median age was 67 years (range 45-78) (Table 1). R140 mutations were more common than R172 mutations (88% vs 12%). At entry, 3 pts (19%) had relapsed following allogeneic stem cell transplant and 11 (69%) had failed prior treatment (Tx) with a hypomethylating agent (HMA). Six pts (38%) had received ≥2 prior anticancer Tx for MDS. MDS pts in the dose-finding phase received daily enasidenib doses of 60 mg (n=1), 150 mg (1), 200 mg (3), or 300 mg (1); 10 pts received enasidenib 100 mg QD. Median number of Tx cycles was 3 (range 1-25); 5 pts (31%) received ≥6 enasidenib cycles and 4 pts (25%) received ≥12 cycles. Grade 3-4 Tx-emergent AEs (TEAEs) were reported for 13 pts (81%); the most frequent were hyperbilirubinemia (n=5, unconjugated), pneumonia (n=4), thrombocytopenia (n=3) and hypokalemia (n=3). Seven pts (44%) had a grade 3-4 drug-related TEAE. One pt was not evaluable for response. ORR was 53% (8/15), including 1 pt who achieved CR (Figure 1). Of 10 evaluable pts who had received prior HMA Tx, 5 (50%) had a response with enasidenib, including the pt in CR. Of the 4 pts with no prior MDS Tx, 2 responded (1 PR, 1 mCR). Median time to CR, PR, or mCR (sustained ≥4 weeks) was 24 days (range 17-87) from beginning enasidenib Tx, and to HI (sustained ≥8 weeks) was 11 days (11-60). Two pts experienced disease progression. Median OS was not reached after a median follow-up of 4.7 months. FoundationOne® data were available for 12 pts; the most frequently observed known somatic co-occurring mutations were ASXL1 and SRSF2 (Figure 2). Although trends between response and co-occurring ASXL1 and/or SRSF2 mutations were observed, the small number of pts tested prevents definitive conclusions. Discussion: Daily Tx with oral enasidenib monotherapy was well tolerated and induced responses in more than one-half of these MDS pts with mIDH2, 50% of whom had higher-risk disease, and two-thirds of whom had failed prior HMA Tx. Notably, one-half of evaluable MDS pts who had failed prior HMA Tx had a response, including a CR, with enasidenib monotherapy. Only 2 pts experienced disease progression during Tx. Mutational testing is rapidly becoming essential to diagnosis and prognostication in MDS, and assessment of IDH2 mutations can identify MDS pts who may benefit from targeted Tx with enasidenib. Disclosures Stein: Seattle Genetics: Research Funding; Agios Pharmaceuticals: Other: Advisory Board, Research Funding; Celgene: Other: Advisory Board, Research Funding; Novartis: Consultancy. Fathi:Merck: Other: Advisory Board participation; Agios Pharmaceuticals: Other: Advisory Board participation; Seattle Genetics: Consultancy, Other: Advisory Board participation, Research Funding; Celgene: Consultancy, Research Funding; Bexalata: Other: Advisory Board participation. DiNardo:Novartis: Other: advisory board, Research Funding; Agios: Other: advisory board, Research Funding; Celgene: Research Funding; Daiichi Sankyo: Other: advisory board, Research Funding; Abbvie: Research Funding. Pollyea:Celgene: Other: advisory board, Research Funding; Ariad: Other: advisory board; Glycomimetics: Other: DSMB member; Alexion: Other: advisory board; Pfizer: Other: advisory board, Research Funding. Roboz:Celgene: Consultancy; Astex: Consultancy; Agios: Consultancy; Pfizer: Consultancy; Juno: Consultancy; Genoptix: Consultancy; Amgen: Consultancy; MEI Pharma: Consultancy; Janssen: Consultancy; AstraZeneca: Consultancy; Onconova: Consultancy; Sunesis: Consultancy; Novartis: Consultancy; Roche/Genentech: Consultancy; MedImmune: Consultancy; Celator: Consultancy; Amphivena: Consultancy. Sekeres:Amgen Inc.: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees; Millenium/Takeda: Membership on an entity's Board of Directors or advisory committees. Stone:Pfizer: Consultancy; Sunesis Pharmaceuticals: Consultancy; Abbvie: Consultancy, Membership on an entity's Board of Directors or advisory committees; Agios: Consultancy; Amgen: Consultancy; Celator: Consultancy; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees; Karyopharm: Consultancy; Novartis: Consultancy; Jansen: Consultancy; Juno Therapeutics: Consultancy; ONO: Consultancy; Seattle Genetics: Consultancy; Merck: Consultancy; Roche: Consultancy; Xenetic Biosciences: Consultancy. Attar:Agios Pharmaceuticals, Inc.: Employment, Equity Ownership. Tosolini:Celgene: Employment, Equity Ownership. Xu:Celgene: Employment, Equity Ownership. Amatangelo:Celgene: Employment, Equity Ownership. Gupta:Celgene: Employment, Equity Ownership. Knight:Celgene: Employment, Equity Ownership. De Botton:Agios, Celgene, Pfizer, Novartis, Pierre Fabre, Servier: Consultancy, Honoraria, Research Funding. Kantarjian:Amgen: Research Funding; ARIAD: Research Funding; Bristol-Myers Squibb: Research Funding; Pfizer Inc: Research Funding; Delta-Fly Pharma: Research Funding; Novartis: Research Funding.

Description: Introduction: The randomized COMPLEMENT 2 study demonstrated a statistically significant improvement in independent reviewer committee-assessed median progression-free survival (PFS) in patients with relapsed chronic lymphocytic leukemia (CLL) who were treated with ofatumumab plus fludarabine and cyclophosphamide (OFC) compared with fludarabine and cyclophosphamide (FC) alone (28.9 vs. 18.8 months, p=0.0032) and that the addition of O was well tolerated (Robak T, et al. Haematologica 2015;100:abstract LB219). Moreover, the median overall survival was 56.4 months in the OFC arm and 45.8 months in the FC arm (p=0.1410) with a median follow-up of 34 months. In addition to the PFS benefit, it is important to consider the impact of adding O to FC on health-related quality of life (HRQoL) and patient-reported symptoms. Methods: In the COMPLEMENT 2 trial, patients with relapsed CLL (N=365) were randomized to either OFC or FC. F and C were administered as intravenous infusions (F: 25 mg/m2, Days 1-3 every 28 days for 6 cycles; C: 250 mg/m2, Days 1-3 every 28 days for 6 cycles). O was also administered intravenously (Cycle 1: 300 mg Day 1 and 1000 mg Day 8, subsequent cycles: 1000 mg Day 1). During the trial, the EORTC QLQ-C30 v3.0 and the QLQ-CLL16 questionnaires were administered at baseline, during Cycle 4 of 6 and throughout follow-up. Specified patient-reported endpoints were HRQoL as reported by the global health status/QoL domain of the QLQ-C30 questionnaire and a B symptom index including patient-reported symptoms of fatigue, night sweats, temperature changes, and weight loss as reported by certain items of the QLQ-C30 and QLQ-CLL16 questionnaires. Results: The least square mean change in HRQoL, measured on a scale scored from 0 (worse) to 100 (best), improved between baseline and Cycle 4 by 8.3 points in the OFC arm vs. 4.8 points in the FC arm. Although there was no significant difference between the least square mean changes in the two arms (p=0.09), the OFC arm surpassed the 5-point difference defined as being a clinically relevant change (Osoba D, et al. J Clin Oncol 1998;16;139-144). The least square mean change in B symptom index, measured on a scale of 0-100 with 0 meaning no symptoms, improved from baseline to Cycle 4 by 5.6 points and 4.5 points in the OFC and FC arms, respectively, with no significant difference between the arms (p=0.49). Patients who achieved a complete or partial response to therapy showed a larger mean improvement in B symptoms (OFC 6.5 improvement, FC 7.5 improvement) than those who did not respond (OFC 4.3 improvement, FC 3.5 worsening of symptoms) but these differences between the arms were not significant (p=0.51 and p=0.22, respectively). During follow-up, patients who did not progress maintained a consistent level of HRQoL in both arms (Figure). Conclusion: This study demonstrates durable improvements in both HRQoL and patient-reported B symptoms for patients being treated for relapsed CLL. Although there are no significant differences observed between the OFC and FC treatment arms in terms of the least square mean change in HRQoL or B symptom scores, the improvement in PFS in the OFC arm reported previously (Robak T, et al. Haematologica 2015;100:abstract LB219) suggests that these patients may enjoy HRQoL and symptom improvements for a longer duration. Figure 1. Least Squares Mean Change in HRQoL from Baseline Figure 1. Least Squares Mean Change in HRQoL from Baseline Disclosures Robak: GlaxoSmithKline: Research Funding; Novartis: Consultancy, Honoraria, Research Funding. Off Label Use: Ofatumumab (Arzerra) is approved in the frontline and refractory CLL setting but not in relapsed CLL. This Abstract presents the Health related quality of life and patient reported outcomes in patients receiving ofatumumab in combination with fludarabine and cyclophosphamide (FC) versus FC alone. Kryachok:GlaxoSmithKline: Honoraria, Other: Investigator for Study. Homenda:GlaxoSmithKline: Honoraria, Other: Intestigator in Clinical Trial - OMB110913 (COMPLEMENT 2). Blonski:GlaxoSmithKline: Research Funding. McKeown:GlaxoSmithKline: Equity Ownership; Novartis: Employment, Equity Ownership. Chang:GlaxoSmithKline: Equity Ownership; Novartis: Employment, Equity Ownership. Manson:GlaxoSmithKline: Employment, Equity Ownership; Novartis: Employment, Equity Ownership. Lisby:Genmab: Employment. Gupta:Novartis: Employment, Equity Ownership; GlaxoSmithKline: Equity Ownership.

Description: Abstract 1632 Background: OFA is a fully human monoclonal antibody that binds to both the large and small extracellular loops of CD20. OFA is currently approved for patients (pts) with refractory chronic lymphocytic leukemia and has demonstrated activity in non-Hodgkin's lymphomas, including follicular lymphoma (FL). We previously reported results of a phase II study of OFA in combination with CHOP (cyclophosphamide 750 mg/m2, doxorubicin 50 mg/m2, vincristine 1.4 mg/m2, prednisone 100 mg daily for 5 days) chemotherapy (O-CHOP) in pts with previously untreated FL (Czuczman et al. Br J Haematol. 2012;157:438). We now report updated efficacy, safety and pharmacokinetic (PK) follow-up data for this study. This trial is registered at www.clinicaltrials.gov (NCT00494780). Methods: Fifty-nine pts with previously untreated FL were randomized to OFA 500 mg (n = 29) or 1000 mg (n = 30) on day 1, with CHOP on day 3, every 3 weeks for 6 cycles. The primary end point was overall response rate (ORR), as assessed by an independent end points review committee. Secondary end points included complete response (CR), progression-free survival (PFS), overall survival, adverse events (AEs) and PK. Follow-up assessments after therapy were done every 3 months (mo) until mo 12 and then every 6 mo until alternative FL therapy or mo 60. Positron emission tomography (PET) was done at baseline and 3 mo after last therapy. Blood samples for PK analyses were collected to determine OFA serum concentrations, and noncompartmental methods were used to estimate PK parameter values. Results: Fifty-eight pts received therapy; 1 pt in the 1000-mg group withdrew before initiation of therapy. The ORR was 90% for the 500-mg group (n=29) and 100% for the 1000-mg group (n=29); 55% of pts achieved CR or unconfirmed CR (CRu), including 67% of pts with a Follicular Lymphoma International Prognostic Index (FLIPI) score of 3–5. At baseline, 57 pts were PET positive, and 49 pts underwent repeat PET scans after therapy. Forty of 49 pts (82%) became PET negative, including 27 of 29 (93%) pts who achieved CR/CRu and 13 of 20 pts (65%) who achieved partial response (PR). With a median follow-up of 33.8 mo, the median PFS for the 500-mg group was 27.6 mo and the median PFS for the 1000-mg group was not reached (P=0.46). Median PFS for pts with FLIPI scores of 0–1 (n=17), 2 (n=20) and 3–5 (n=21) was not reached, 27.6 mo and 27.6 mo, respectively (P=0.68). Median PFS for pts (n=32) who achieved CR/CRu was also not reached and was 28.3 mo for pts (n=23) achieving PR. Median PFS for PR pts who were PET positive and PET negative after therapy was not reached and 28.3 mo, respectively. No deaths have been reported. No hematologic serious AEs (SAEs) were experienced during the follow-up period. During the follow-up period, non-hematologic SAEs were reported in 1 pt in the 500-mg group (pneumonia) and 5 pts in the 1000-mg group (abdominal hernia, erysipelas, intervertebral disc protrusion, meniscus lesion and vulval cancer); none were ofatumumab-related. After repeated dosing, OFA clearance values were 6.3 and 5.9 mL/h, and half-life values were 27.2 and 26.8 days in the 500-mg and 1000-mg groups, respectively. Conclusions: O-CHOP achieved durable remissions in previously untreated pts with FL. There were no observed PK or PFS differences between the 500-mg and 1000-mg arms, but the study was not powered to detect such differences. O-CHOP was effective in pts with high-risk FLIPI scores, and CR/CRu and PFS rates were not affected by FLIPI score. PET status after therapy did not predict PFS in responding pts, although the study was too small to make such a determination. These results indicate that O-CHOP should be studied as a therapy for FL pts with high-risk FLIPI scores. Disclosures: Czuczman: GlaxoSmithKline: Advisory board Other, Honoraria. Off Label Use: Ofatumumab in follicular lymphoma. Belada:GlaxoSmithKline: Research Funding. Mayer:Roche: Consultancy, Research Funding; GlaxoSmithKline: Consultancy, Research Funding. Gupta:GlaxoSmithKline: Employment. Lin:GlaxoSmithKline: Employment, Equity Ownership. Winter:GlaxoSmithKline: Employment, Equity Ownership. Goldstein:GlaxoSmithKline: Employment, Equity Ownership. Jewell:GlaxoSmithKline: Employment, Equity Ownership. Lisby:Genmab: Employment, Equity Ownership.

Description: Background: Despite encouraging progress in treatment results, CLL remains incurable and patients (pts) eventually relapse. Currently, the effects of maintenance therapy are unknown for CLL. OFA, a human anti-CD20 monoclonal antibody, has proven efficacy as a monotherapy in refractory CLL. PROLONG is an open-label, two-arm randomized study of OFA versus observation (obs) for pts in remission after induction treatment for relapsed CLL. Here, we report interim analysis results for the key primary and secondary endpoints of the study. Methods: Pts in CR or PR after 2nd or 3rd line treatment for CLL were randomized 1:1 to receive OFA (300 mg followed 1 week later by 1000 mg every 8 weeks for up to 2 years) or observation. Pts on OFA received premedication with acetaminophen, antihistamine and glucocorticoid. Pts were stratified by number and type of prior therapy, and remission status (CR or PR) after induction treatment. The primary endpoint was progression free survival (PFS) from randomization as assessed by investigator. The predefined interim analysis of efficacy occurred at 2/3 study events (minimum 187), with a p

Description: BACKGROUND: Genomic aberrations and IGHV mutation status are established prognostic factors in CLL. With TP53, NOTCH1, SF3B1, ATM, MYD88, FBXW7, BIRC3 and POT1 recurrently mutated genes were found in CLL and were discussed to associate with disease characteristics and to affect therapy efficacy and outcome. METHODS: We assessed the incidence and impact of gene mutations in the COMPLEMENT1 trial (1st line Chl vs. O-Chl). Pretreatment samples were available from 376 patients (84.1%) and this cohort was representative of the full trial population. Mutations were analyzed by amplicon-based targeted NGS using Illumina Miseq for all coding exons (TP53, ATM, MYD88, FBXW7, BIRC3 and POT1) or hotspot exons (NOTCH1, SF3B1). Additionally, the exact variant frequency was determined. RESULTS: The incidences of gene mutations were: TP53 8.2%, NOTCH1 14.9%, SF3B1 14.1%, ATM 10.9%, MYD88 2.7%, FBXW7 3.5%, POT1 7.7%, and BIRC3 2.7%. Regarding baseline characteristics, we found significant associations: TP53mut with high ß2MG (p=0.01), 17p- (p

Description: Abstract 921 Background: Patients with chronic lymphocytic leukemia (CLL) refractory to fludarabine and alemtuzumab (FA-ref) or refractory to fludarabine with bulky (〉5 cm) lymphadenopathy (BF-ref) have poor prognosis with salvage regimens (Tam et al. Leuk Lymphoma 2007). Ofatumumab, a human CD20 monoclonal antibody, was recently approved by the US FDA and EMEA for treatment of CLL refractory to fludarabine and alemtuzumab based on the interim analysis of the pivotal international clinical trial, which included data from 138 patients with FA-ref and BF-ref CLL. At the interim analysis, the overall response rate (ORR; primary endpoint) with single-agent ofatumumab was 58% (99% CI: 40, 74) in the FA-ref group and 47% (99% CI: 32, 62) in the BF-ref group (Wierda et al. J Clin Oncol 2010). Here, we report the final result for the primary endpoint in 206 patients with FA-ref or BF-ref CLL enrolled in this study. Methods: Patients with FA-ref or BF-ref CLL received 8 weekly doses of ofatumumab followed by 4 monthly doses (dose 1, 300 mg; doses 2–12, 2000 mg). Premedication included acetaminophen, antihistamine and glucocorticoid. The primary endpoint (ORR, 1996 NCI-WG criteria) was evaluated over the 24-week treatment period by an Independent Endpoint Review Committee (IRC). Secondary endpoints included duration of response, progression-free survival (PFS), overall survival (OS) and safety. Results: Baseline characteristics are summarized in the Table; 89% and 50% of patients completed 8 and 12 ofatumumab doses, respectively. The ORR (95% CI) by IRC evaluation was 51% (40, 61) for the FA-ref group and 44% (35, 64) for the BF-ref group. Two patients in the BF-ref group achieved complete remission (Table). Results for time-to-event analyses are shown in the Table. Infusion-related AEs occurred in 63% of patients, which primarily occurred during doses 1 and 2, and diminished with subsequent doses. Infusion-related reactions were grade 1–2 events in 95% of patients; no fatal reactions were reported. The most common (≥5% of all patients) grade ≥3 adverse events (AEs) that occurred from start of treatment until 30 days after the last infusion were infections (24%), neutropenia (12%) and anemia (5%). The most common grade ≥3 infection was pneumonia (8% of patients). Fatal infections occurred in 8% of patients (13% in FA-ref; 5% in BF-ref groups). Grade 3–4 thrombocytopenia occurred in 8 patients (4%), febrile neutropenia in 4 patients (2%) and autoimmune hemolytic anemia in 2 patients (1%). Early death (within 8 weeks from start of treatment) occurred in 5 patients (5%) in the FA-ref group (infections, n=5) and 4 patients (4%) in the BF-ref group (infections, n=2; myocardial infarction, n=1; pulmonary edema, n=1). Conclusions: These final results from the pivotal trial clearly demonstrate the efficacy and safety of ofatumumab monotherapy in this heavily pretreated patient population with FA-ref and BF-ref CLL. Additional data analyses are ongoing, and efficacy outcomes for patient subgroups will be presented. Disclosures: Wierda: GlaxoSmithKline: Honoraria, Research Funding. Kipps:GlaxoSmithKline: Research Funding. Mayer:GlaxoSmithKline: Consultancy, Research Funding. Robak:GlaxoSmithKline: Consultancy, Honoraria, Research Funding; Genmab: Consultancy, Research Funding; Roche: Consultancy, Honoraria, Research Funding. Furman:GlaxoSmithKline: Consultancy, Speakers Bureau; Genentech: Consultancy, Speakers Bureau; Cephalon, Inc.: Speakers Bureau; Celegene: Consultancy; Calistoga: Consultancy. Stilgenbauer:Amgen: Research Funding; Bayer: Consultancy, Honoraria, Research Funding; Boehringer-Ingelheim: Consultancy, Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding; Genzyme: Consultancy, Honoraria, Research Funding; GSK: Consultancy, Honoraria, Research Funding; Mundipharma: Consultancy, Honoraria, Research Funding; Roche: Consultancy, Honoraria, Research Funding; Sanofi Aventis: Research Funding. Cartron:GlaxoSmithKline: Honoraria; Roche: Honoraria. Padmanabhan:GlaxoSmithKline: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. Chan:GlaxoSmithKline: Employment. Gupta:GlaxoSmithKline: Employment. Gorczyca:GlaxoSmithKline: Employment. Davis:GlaxoSmithKline: Employment. Losic:Genmab A/S: Employment, Equity Ownership. Lisby:Genmab A/S: Employment. Österborg:GlaxoSmithKline: Consultancy, Honoraria, Research Funding; Genzyme: Consultancy, Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding; Merck KGaA: Research Funding.

Description: Abstract 207 Introduction: Chemoimmunotherapy regimens have become the treatment standard for patients with CLL. Ofatumumab is a human monoclonal antibody that targets a unique small-loop epitope on CD20 and elicits rapid and efficient in vitro complement-dependent cytotoxicity, as well as antibody-dependent cellular cytotoxicity. Recent studies demonstrated single-agent ofatumumab activity, with high overall response rates (ORR) in patients with refractory CLL. We conducted an international, randomized, parallel group, Phase II trial with two doses of ofatumumab combined with fludarabine and cyclophosphamide (FC) in previously untreated patients with CLL to evaluate the efficacy and tolerability of this chemoimmunotherapy regimen. Methods: Previously untreated patients (N=61) with active CLL (by NCI-WG guidelines) were randomized to receive ofatumumab 500 mg (Group A) or 1000 mg (Group B) on day 1, combined with fludarabine (25 mg/m2 IV daily; days 1–3) and cyclophosphamide (250 mg/m2 IV daily; days 1–3) every 4 weeks for a total of 6 courses. In both Groups, the first dose of ofatumumab was 300 mg. Dose reduction of FC, but not ofatumumab, was allowed. Premedication for ofatumumab was paracetamol and antihistamine prior to each infusion, and glucocorticoid prior to infusions 1 and 2. Neutrophil growth factor and anti-infective prophylaxis were not mandated. The primary endpoint was complete response (CR) rate (1996 NCI-WG criteria) assessed by an Independent Review Committee (IRC), measured from the start of treatment until 3 months after the last infusion. Safety evaluations included investigator-reported adverse events (AEs) and deaths. Follow-up continues for collection of time-to-event endpoints. Results: Data from all 61 patients were available for response assessment (primary endpoint). Pretreatment characteristics are shown in the Table. 71% and 57% of patients in Groups A and B, respectively, completed all 6 courses of O-FC treatment. The CR rate (95% CI) by IRC evaluation was 32% (17, 51%) for Group A and 50% (31, 69%) for Group B; the ORR (95% CI) was 77% (59, 90%) and 73% (54, 88%), respectively (Table). The median progression-free survival has not been reached with the short median follow up of 8 months. No CTC grade 3–4 infusion-related reactions on the day of ofatumumab infusion were reported. During treatment and up to 30 days following the last dose, the most common (〉10% of patients) grade 3–4 AEs reported by investigators were infections in 11 patients (Group A, n=4; Group B, n=7) including febrile neutropenia in 3 patients in each Group, and hematologic AEs including neutropenia in 29 patients (Group A, n=11; Group B, n=18), anemia in 8 patients (Group A, n=2; Group B, n=6) and thrombocytopenia in 9 patients (Group A, n=2; Group B, n=7); grade 3–4 hemolytic anemia occurred in 2 patients in Group A and 1 in Group B; one patient in Group B died (19 days from last dose) with dyspnea (etiology unknown). Beyond the AE reporting period mentioned above, one patient in Group A died (50 days from last dose) due to febrile neutropenia during the follow up period. Results from additional analysis of data will be presented at the meeting. Conclusions: The O-FC regimen is highly active in previously untreated patients with CLL at both ofatumumab doses investigated and may offer a new chemoimmunotherapy treatment option in these patients. AEs with the O-FC regimen were manageable with no unexpected toxicities. The 1000 mg dose of ofatumumab is currently being evaluated in combination with chemotherapy in other studies for patients with CLL. Disclosures: Wierda: Genmab, GlaxoSmithKline: Honoraria, Research Funding. Off Label Use: Ofatumumab is an investigational anti-CD20 monoclonal antibody, currently under development for the treatment of B-cell malignancies (chronic lymphocytic leukemia, diffuse large B-cell lymphoma, Waldenstroms macroglobulinemia and follicular lymphoma) as well as autoimmune diseases (rheumatoid arthritis and multiple sclerosis). Kipps:Physicians' Education Resource, Educational Concepts: Speakers Bureau; Genmab, Abbott Industries, Celgene, Biogen Idec, Cephalon, sanofi-aventis, Medimmune, Memgem, Genentech: Research Funding. Dürig:GlaxoSmithKline: Honoraria. Griskevicius:GlaxoSmithKline, Genmab: Research Funding. Stilgenbauer:GlaxoSmithKline, Genmab: Consultancy, Honoraria, Research Funding. Mayer:GlaxoSmtihKline: Consultancy. Smolej:Bayer Schering: Honoraria. Padmanabhan:GlaxoSmithKline: Consultancy, Honoraria; Celgene, Genentech: Consultancy. Gorczyca:GlaxoSmithKline: Employment. Chan:GlaxoSmithKline: Employment. Gupta:GlaxoSmithKline: Employment. Andersen:H. Lundbeck A/S: Shares ownership; Novo Nordisk A/S, H. Lundbeck A/S and Genmab A/S: Consultancy. Strange:Genmab: Employment. Nielsen:Genmab: Employment. Russell:Genmab: Employment, Equity Ownership.