Frontline bortezomib and rituximab for the treatment of newly diagnosed high tumour burden indolent non-Hodgkin lymphoma: a multicentre phase II study

There is a lack of published data examining non-cytotoxic options for the frontline treatment of patients with high-tumour burden (HTB) indolent non-Hodgkin lymphoma (iNHL). We completed a multicentre phase II study for patients with untreated HTB iNHL (NCT00369707) consisting of three induction cycles of weekly bortezomib and rituximab followed by an abbreviated consolidation. Forty-two patients were treated and all were evaluable; the most common histology was follicular lymphoma (FL) (n = 33, 79%). Patient characteristics included median age 62 years (40-86); 38% bulky disease; 19% malignant effusions; 91% advanced-stage disease; and median FL International Prognostic Index (FLIPI) score was 3. Therapy was well tolerated with few grade 3/4 toxicities including minimal neurotoxicity. On intent-to-treat, the overall response rate (ORR) at end of therapy was 70% with a complete remission (CR) rate of 40% (FL: ORR 76%, CR 44%). With 50-month median follow-up, 4-year progression-free survival (PFS) was 44% with 4-year overall survival (OS) of 87% (FL: 44% and 97%, respectively). Four-year PFS for FLIPI 0-2 vs. 3-5 was 60% vs. 26% respectively (P = 0·02), with corresponding OS rates of 92% and 81% respectively (P = 0·16). Collectively, bortezomib/rituximab is a non-cytotoxic therapeutic regimen that was well tolerated and resulted in long-term survival rates approximating prior rituximab/cytotoxic chemotherapy series for untreated HTB FL.

Comparison of the prognostic utility of the revised International Prognostic Scoring System and the French Prognostic Scoring System in azacitidine-treated patients with myelodysplastic syndromes

The revised International Prognostic Scoring System (IPSS-R) was developed in a cohort of untreated myelodysplastic syndromes (MDS) patients. A French Prognostic Scoring System (FPSS) was recently reported to identify differential survival among azacitidine-treated patients with high-risk MDS. We applied the FPSS and IPSS-R to 150 patients previously randomized to azacitidine monotherapy or a combination of azacitidine with entinostat (a histone deacetylase inhibitor). Neither score predicted response but both discriminated patients with different overall survival (OS; median OS, FPSS: 9·7, 14·7, and 25·3 months, P = 0·018; IPSS-R: 12·5, 11·3, 20·8, and 36 months, P = 0·005). Statistical analysis suggested no improvement in OS prediction for the FPSS over the IPSS-R in azacitidine-treated patients.

Constraints on cosmic strings from the LIGO-Virgo gravitational-wave detectors

Cosmic strings can give rise to a large variety of interesting astrophysical phenomena. Among them, powerful bursts of gravitational waves (GWs) produced by cusps are a promising observational signature. In this Letter we present a search for GWs from cosmic string cusps in data collected by the LIGO and Virgo gravitational wave detectors between 2005 and 2010, with over 625 days of live time. We find no evidence of GW signals from cosmic strings. From this result, we derive new constraints on cosmic string parameters, which complement and improve existing limits from previous searches for a stochastic background of GWs from cosmic microwave background measurements and pulsar timing data. In particular, if the size of loops is given by the gravitational backreaction scale, we place upper limits on the string tension Gμ below 10(-8) in some regions of the cosmic string parameter space.

Prolonged administration of azacitidine with or without entinostat for myelodysplastic syndrome and acute myeloid leukemia with myelodysplasia-related changes: results of the US Leukemia Intergroup trial E1905

PURPOSE

Although azacitidine (AZA) improves survival in patients with high-risk myelodysplastic syndrome, the overall response remains approximately 50%. Entinostat is a histone deacetylase inhibitor that has been combined with AZA with significant clinical activity in a previous phase I dose finding study.

DESIGN

Open label phase II randomized trial comparing AZA 50 mg/m(2)/d given for 10 days ± entinostat 4 mg/m(2)/d day 3 and day 10. All subtypes of myelodysplasia, chronic myelomonocytic leukemia, and acute myeloid leukemia with myelodysplasia-related changes were eligible for the study. The primary objective was the rate of hematologic normalization (HN; complete remission + partial remission + trilineage hematological improvement).

RESULTS

One hundred forty-nine patients were analyzed, including 97 patients with myelodysplastic syndrome and 52 patients with acute myeloid leukemia. In the AZA group, 32% (95% CI, 22% to 44%) experienced HN and 27% (95% CI, 17% to 39%) in the AZA + entinostat group. Both arms exceeded the HN rate of historical control (Cancer and Leukemia Group B 9221 trial), but only the AZA group fulfilled the primary objective of the study. Rates of overall hematologic response were 46% and 44%, respectively. Median overall survivals were 18 months for the AZA group and 13 months for the AZA + entinostat group. The combination arm led to less demethylation compared with the monotherapy arm, suggesting pharmacodynamic antagonism.

CONCLUSION

Addition of entinostat to AZA did not increase clinical response as defined by the protocol and was associated with pharmacodynamic antagonism. However, the prolonged administration of AZA by itself seems to increase HN rate compared with standard dosing and warrants additional investigation.

Phase 2 study of VcR-CVAD with maintenance rituximab for untreated mantle cell lymphoma: an Eastern Cooperative Oncology Group study (E1405)

Rituximab, bortezomib, modified hyper-cyclophosphamide, doxorubicin, vincristine, dexamethasone (VcR-CVAD) induction chemoimmunotherapy and maintenance rituximab (MR) were evaluated for efficacy and safety in Eastern Cooperative Oncology Group protocol E1405. Patients with previously untreated mantle cell lymphoma received VcR-CVAD chemotherapy every 21 days for 6 cycles, followed by MR for 2 years. Transplant-eligible patients had the option of autologous stem cell transplantation (ASCT) consolidation instead of MR. The primary end point was the complete response (CR) rate to VcR-CVAD. The secondary end points were overall response rate (ORR), progression-free survival (PFS), overall survival (OS), and toxicities. Seventy-five eligible patients with a median age of 62 (range 40-76) were enrolled. The ORR was 95% and a CR was achieved in 68% of patients. After a median follow-up of 4.5 years, 3-year PFS and OS were 72% and 88%, respectively. No substantial difference in PFS or OS was observed between patients treated with MR (n = 44) vs ASCT (n = 22). There were no unexpected toxicities. VcR-CVAD produced high ORR and CR rates in mantle cell lymphoma. MR after VcR-CVAD induction performed similarly to ASCT and may improve response duration. Randomized clinical trials comparing MR against ASCT should be considered and randomized clinical trials evaluating bortezomib's contribution to conventional therapy are under way. This study was registered at www.clinicaltrials.gov as #NCT00433537.

New agents for the treatment of lymphoid leukemia and lymphoma: focus on recent FDA approvals

Leukemia and lymphoma are systemic malignancies that represent half of all childhood cancers, though 90% occur in adults. Various treatment options are available, but therapy is mainly systemic chemotherapy plus appropriate monoclonal antibodies. In certain situations radiotherapy and bone marrow transplantation play a role. Some types/subtypes of these diseases are potentially curable, yet many leukemias and lymphomas do not properly respond to current therapies. Although the FDA (US Food and Drugs Administration) approvals of new drugs have shown a small increasing trend between 2007-2012, overall, the trend of new approvals remains relatively steady between 2006-2013, with a peak of 39 new drugs approved in 2012 and a drop in the new FDA drug approvals in 2013, to 27. Drugs approved for cancer treatment have shown a similar trend. Between 2006-2013, at least one drug was approved every year for the treatment of particular types of lymphoma or leukemia, except in 2010, with a peak of 5 new approvals in 2012. Between January 2013-March 2014, several important new approvals were made: ibrutinib for the treatment of CLL and mantle cell lymphoma (MCL), obinutuzumab for the treatment of CLL (in combination with chlorambucil), and lenalidomide for the treatment of mantle cell lymphoma. The results, importance, adverse effects and mechanisms of action of these agents are discussed in this review. These results held promise and their discovery and approval for the treatment of CLL and MCL is a major step forward. However, the emergence of resistance and the lack of cures need to be addressed by rational development of combination therapy, as well as development of novel drugs with enhanced potency or different mechanism of action, to achieve better overall and complete response rates with decreased toxicity.

Noninvasive phosphorus magnetic resonance spectroscopic imaging predicts outcome to first-line chemotherapy in newly diagnosed patients with diffuse large B-cell lymphoma

RATIONALE AND OBJECTIVES

Based on their association with malignant proliferation, using noninvasive phosphorus MR spectroscopic imaging ((31)P MRSI), we measured the tumor content of the phospholipid-related phosphomonoesters (PME), phosphoethanolamine and phospholcholine, and its correlation with treatment outcome in newly diagnosed patients with diffuse large B-cell lymphoma (DLBCL) receiving standard first-line chemotherapy.

EXPERIMENTAL DESIGN

The PME value normalized to nucleoside triphosphates (PME/NTP) was measured using (31)P MRSI in tumor masses of 20 patients with DLBCL before receiving standard first-line chemotherapy. Response at 6 months was complete in 13 patients and partial in seven. Time to treatment failure (TTF) was ≤11 months in eight patients, from 18 to 30 months in three, and ≥60 months in nine.

RESULTS

On a t test, the pretreatment tumor PME/NTP mean value (SD, n) of patients with a complete response at 6 months was 1.42 (0.41, 13), which was significantly different from the value of 2.46 (0.40, 7) in patients with partial response (P < .00001). A Fisher test significantly correlated the PME/NTP values with response at 6 months (sensitivity and specificity at 0.85, P < .004) while a Cox proportional hazards regression significantly correlated the PME/NTP values with TTF (hazard ratio = 5.21, P < .02). A Kaplan-Meier test set apart a group entirely composed of patients with TTF ≤ 11 months (hazard ratio = 8.66, P < .00001).

CONCLUSIONS

The pretreatment tumor PME/NTP values correlated with response to treatment at 6 months and time to treatment failure in newly diagnosed patients with DLBCL treated with first-line chemotherapy, and therefore they could be used to predict treatment outcome in these patients.

Low NK cell counts in peripheral blood are associated with inferior overall survival in patients with follicular lymphoma

Host immune responses influence follicular lymphoma (FL) outcomes. To test our hypothesis that immune cells in blood reflect that response, we assessed by peripheral blood flow cytometry in 75 untreated FL patients the absolute counts of: lymphocytes (ALC), CD4(+)T (ACD4C), CD8(+)T (ACD8C) and natural killer (ANKC) cells. Low ANKC was the only parameter associated with inferior overall survival by univariate analysis (p=0.02), and trended to significance in multivariable analysis with ACD4C (p=0.08). Five (24%) patients with low initial ANKC died, while one (2%) with normal/high ANKC has died. In conclusion, evaluation of blood ANKC may be a useful indicator of outcome in previously untreated FL patients.

Novel targeted therapies in peripheral T cell lymphoma

Peripheral T cell lymphomas (PTCL), non-Hodgkin lymphomas characterized by having features of T cells that have matured in the thymus, are a heterogeneous group of clinical entities. Compared with B cell lymphomas, they are less common, more difficult to diagnose and classify, more aggressive, and have inferior outcomes with current treatment paradigms. They are also less completely understood in terms of how different PTCL types correspond to normal T cell development, and in identifying cell signaling pathways as targets for new therapies. Recent studies with novel targeted therapies as single agents or in combination with other drugs have illustrated promising outcomes both for relapsed and frontline PTCL. We first briefly review classification, prognostic indices, and results of initial therapy of various T cell lymphomas. We then review recent studies of chemotherapy, monoclonal antibody-based therapy directed at cell surface targets, small molecule inhibitors of intracellular targets such as histone deacetylases and the proteasome, and agents that disrupt stromal interactions. Investigations that enhance our knowledge of T cell molecular biology and integrate novel targeted agents into the treatment algorithm for PTCL will be keys to improved outcomes for patients with PTCL.

Therapies for mantle cell lymphoma: current challenges and a brighter future

Mantle cell lymphoma (MCL), which accounts for about 6% of non-Hodgkin lymphoma (NHL), is characterized by the chromosomal translocation t(11;14)(q13;q32), resulting in de-regulated expression of cyclin D1. Managing MCL is challenging, because it is incurable with conventional chemotherapy as with indolent NHL, but has a more aggressive natural history. Therapeutic advances have been made in the past decade with the incorporation of targeted therapies into the frontline setting, use of aggressive combination regimens followed by consolidation with high dose therapy and autologous stem cell rescue for a younger population, use of less aggressive combinations in the elderly, and translation of pre-clinical findings to the clinical trial realm with novel agents that hold significant promise in the treatment of this disease. The authors review current standard approaches in the treatment of MCL, and novel findings in the pathogenesis of this disease that may guide the way for further development of modern therapeutic approaches.

Safety and clinical activity of a combination therapy comprising two antibody-based targeting agents for the treatment of non-Hodgkin lymphoma: results of a phase I/II study evaluating the immunoconjugate inotuzumab ozogamicin with rituximab

PURPOSE

Inotuzumab ozogamicin (INO) is an antibody-targeted chemotherapy agent composed of a humanized anti-CD22 antibody conjugated to calicheamicin, a potent cytotoxic agent. We performed a phase I/II study to determine the maximum-tolerated dose (MTD), safety, efficacy, and pharmacokinetics of INO plus rituximab (R-INO) for treatment of relapsed/refractory CD20(+)/CD22(+) B-cell non-Hodgkin lymphoma (NHL).

PATIENTS AND METHODS

A dose-escalation phase to determine the MTD of R-INO was followed by an expanded cohort to further evaluate the efficacy and safety at the MTD. Patients with relapsed follicular lymphoma (FL), relapsed diffuse large B-cell lymphoma (DLBCL), or refractory aggressive NHL received R-INO every 4 weeks for up to eight cycles.

RESULTS

In all, 118 patients received one or more cycles of R-INO (median, four cycles). Most common grade 3 to 4 adverse events were thrombocytopenia (31%) and neutropenia (22%). Common low-grade toxicities included hyperbilirubinemia (25%) and increased AST (36%). The MTD of INO in combination with rituximab (375 mg/m(2)) was confirmed to be the same as that for single-agent INO (1.8 mg/m(2)). Treatment at the MTD yielded objective response rates of 87%, 74%, and 20% for relapsed FL (n = 39), relapsed DLBCL (n = 42), and refractory aggressive NHL (n = 30), respectively. The 2-year progression-free survival (PFS) rate was 68% (median, not reached) for FL and 42% (median, 17.1 months) for relapsed DLBCL.

CONCLUSION

R-INO demonstrated high response rates and long PFS in patients with relapsed FL or DLBCL. This and the manageable toxicity profile suggest that R-INO may be a promising option for CD20(+)/CD22(+) B-cell NHL.

A multicenter phase II trial to determine the safety and efficacy of combination therapy with denileukin diftitox and cyclophosphamide, doxorubicin, vincristine and prednisone in untreated peripheral T-cell lymphoma: the CONCEPT study

This phase II study to determine the safety and efficacy of denileukin diftitox (DD) and cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP) enrolled patients with newly diagnosed peripheral T-cell lymphoma (PTCL). Forty-nine received DD 18 μg/kg/day (days 1, 2) with CHOP (day 3) every 21 days for ≤ 6-8 cycles. Intent-to-treat (ITT) and safety populations comprised all patients. In the ITT population, the overall response rate was 65%, median duration of response was 30 months and median progression-free survival was 12 months. Median overall survival was not attained at the end of the study, and the overall survival rate was 63.3%. The two most frequent treatment-related adverse events (AEs) were fatigue and nausea. Most frequent AEs ≥ grade 3 within the hematologic system were lymphopenia (24.5%), neutropenia (20.4%) and leukopenia (18.4%). Three treatment-related deaths occurred. DD plus CHOP was well tolerated, and progression-free and overall survival improved versus historical comparison with CHOP alone. Confirmation in larger trials is warranted.

Phase II study of rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone immunochemotherapy followed by yttrium-90-ibritumomab tiuxetan in untreated mantle-cell lymphoma: Eastern Cooperative Oncology Group Study E1499

PURPOSE

To test the hypothesis that consolidation therapy with yttrium-90 ((90)Y) -ibritumomab tiuxetan after brief initial therapy with four cycles of rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) in patients with previously untreated mantle-cell lymphoma would be a well-tolerated regimen that would improve outcomes compared with historical R-CHOP data.

PATIENTS AND METHODS

Patients ≥ 18 years old with histologically confirmed mantle-cell lymphoma expressing CD20 and cyclin D1 who had not received any previous therapy and had an Eastern Cooperative Oncology Group performance status of 0 to 2 and adequate organ function were eligible. The study enrolled and treated 57 patients, of whom 56 patients were eligible. Fifty-two patients (50 eligible patients) received (90)Y-ibritumomab tiuxetan. The study design required 52 eligible patients to detect a 50% improvement in the median time to treatment failure (TTF) compared with that reported for six cycles of R-CHOP.

RESULTS

With 56 analyzed patients (median age, 60 years; men, 73%), the overall response rate was 82% (55% complete response/complete response-unconfirmed). With a median follow-up of 72 months, the median TTF was 34.2 months. The median overall survival (OS) has not been reached, with an estimated 5-year OS of 73% (79% for patients ≤ age 65 years v 62% for patients > age 65 years; P = .08 [log-rank test]). There were no unexpected toxicities.

CONCLUSION

R-CHOP given for four cycles followed by (90)Y-ibritumomab tiuxetan compared favorably with historical results with six cycles of R-CHOP in patients with previously untreated mantle-cell lymphoma. This regimen was well tolerated and should be applicable to most patients with this disease.

Radioimmunotherapy in mantle cell lymphoma

Mantle cell lymphoma (MCL), though characterized by the chromosomal translocation t(11; 14) (q13; q32), is a heterogeneous disease. Often termed an aggressive lymphoma in the U.S., but included in indolent lymphoma trials in Europe, MCL is not curable with standard immuno-chemotherapy. There is no single standard initial therapy for this disease. Although standard lymphoma therapies yield high response rates, relapse is inevitable. Unmet needs in MCL include better induction therapy, consolidation treatments to prolong first remission and better therapeutic options for relapsed disease. In this review, we evaluate the role of radioimmunotherapy (RIT) in MCL, a novel strategy combining monoclonal antibodies with radioisotopes to deliver radiation directly to tumour tissue, both in the frontline and relapsed setting.

Tetanus toxoid reactive lymphadenopathy masquerading as T-cell lymphoma

We report a case in which a patient with persistent reactive lymphadenopathy post-tetanus toxoid vaccination was initially diagnosed as having T-cell lymphoma/leukemia. A florid CD4+ T-cell proliferation and pathology interpretation, in the absence of complete clinical information, that these cells co-expressed CD8 led to the initial diagnosis. Better integration of the clinical and pathologic data may have led more rapidly to the final diagnosis. Postvaccination responses can mimic lymphoma.

Efficacy of ocaratuzumab (AME-133v) in relapsed follicular lymphoma patients refractory to prior rituximab

8081

Background: Ocaratzumab, previously known as AME-133v, is a humanized next-generation anti-CD20 monoclonal antibody. It has been optimized with a 13 to 20-fold increase in binding affinity to CD20 and improved binding to the low-affinity (F/F and F/V) polymorphisms of FcγRIIIa (CD16), which are thought to predict lower response rates and shorter duration of responses to rituximab. Methods: In a phase I dose escalation study in relapsed follicular lymphoma (FL) patients, ocaratuzumab was well-tolerated at doses up to 375 mg/m2 (Forero-Torres et al. CCR 2012). In a follow-on phase II trial, 44 patients with relapsed FL following prior rituximab and the low-affinity FcγRIIIa polymorphism (F-carriers) received 375 mg/m2 of ocaratuzumab weekly for 4 doses. In this study, overall response rate (ORR) was 36% and median progression free survival (PFS) was 91 weeks (Ganjoo et al. Haematologica 2011). Results: Amongst the 56 patients receiving 100 and 375 mg/m2 of ocaratuzumab, 8 patients had a previous time to progression of ≤ 180 days following their last rituximab treatment. These patients had a median of 2 prior rituximab treatments, (range 1-6 treatments), and median PFS following last treatment of 159 days. Five of the 8 patients showed a longer PFS after ocaratuzumab administration, compared with last rituximab treatment. All 5 patients expressed the homozygous low-affinity genotype of FcγRIIIa (F/F). At the time of study closure, 3 of the patients were still in remission (indicated by * in the table). Conclusions: This retrospective analysis suggests that ocaratuzumab may be non-cross-resistant to rituximab in patients with the low-affinity FcγRIIIa polymorphism. Prolonged PFS in selected patients following ocaratuzumab suggests that the increased binding affinity to CD16 and improved antibody-dependent cell-mediated cytotoxicity (ADCC) of this antibody is clinically relevant. As a single agent, ocaratuzumab may provide prolonged clinical benefit in relapsed FL patients and a clinical trial comparing ocaratuzumab to rituximab is in preparation. [Table: see text]

Multicenter phase II study of trabectedin in patients with metastatic castration-resistant prostate cancer

BACKGROUND

This multicenter phase II trial evaluated the efficacy and safety of trabectedin in metastatic castration-resistant prostate cancer (CRPC).

PATIENTS AND METHODS

Two schedules were evaluated in three cohorts: weekly as 3-h i.v. infusion at 0.58 mg/m(2) for 3 out of 4 weeks (Cohort A, n = 33), and every 3 weeks (q3wk) as 24-h infusion at 1.5 mg/m(2) (Cohort B1, n = 5) and 1.2 mg/m(2) (Cohort B2, n = 20). The primary end point was prostate-specific antigen (PSA) response; secondary end points included safety, tolerability and time to progression (TTP).

RESULTS

Trabectedin resulted in PSA declines ≥ 50% in 12.5% (Cohort A) and 10.5% (Cohort B2) of patients. Among men pretreated with taxane-based chemotherapy, PSA response was 13.6% (Cohort A) and 15.4% (Cohort B2). PSA responses lasted 4.1-8.6 months, and median TTP was 1.5 months (Cohort A) and 1.9 months (Cohort B2). The dose of 1.5 mg/m(2) (approved for soft tissue sarcoma) given as 24-h infusion q3wk was not tolerable in these patients. At 1.2 mg/m(2) q3wk and 0.58 mg/m(2) weekly, the most common adverse events were nausea, fatigue and transient neutropenia and transaminase increase.

CONCLUSIONS

Two different trabectedin schedules showed modest activity in metastatic CRPC. Further studies may require identification of predictive factors of response in prostate cancer.

Abstract 3857: Smac mimetic TL32711 and TRAIL synergistically induce apoptosis of germinal center B lymphoma cells

TL32711, a Smac mimetic in clinical testing, potently targets Inhibitor of Apoptosis Proteins (IAPs, including cIAPs and XIAP) to unblock intrinsic and extrinsic pathways, enabling caspase-dependent apoptosis via multiple signals including TRAIL (Tumor Necrosis Factor-Related Apoptosis Inducing Ligand). TL32711 also inactivates canonical and activates non-canonical NF-κB signaling through cIAPs. We investigated the pro-apoptotic effects of TL32711, alone and in combination with TRAIL to activate the extrinsic pathway, in a panel of B cell lymphoma cell lines representing germinal center/follicular (GC) vs activated B cell (ABC) histologies. We hypothesized that the efficacy of this potential combination therapeutic strategy might differ between GC and ABC lymphoma types, as ABC are reported to be NF-kB dependent. We used the following EBV negative cell lines: WSU- FSCCL t(14:18)+ follicular lymphoma (FL), FC-TxFL2 t(14:18)+ transformed FL and SU-DHL4 GC-type diffuse large B cell lymphoma (DLBCL) as examples of GC origin lymphomas. U2932 and TMD8 served as ABC-type DLBCL. Apoptosis was determined by annexin V staining after 48 hr incubation (TL32711 added 2-3 hr after TRAIL). The contribution of the different apoptotic pathways was determined by caspase-3 (common), -8 (extrinsic), and-9 (intrinsic) activity, assessed by flow cytometric methods and Western blot. TL32711 had little effect as a single agent on any of these B cell lymphoma cell lines at ≤ 100nM, though apoptosis was induced at 10-20 µM in GC types. TRAIL alone (10-25 ng/ml) induced apoptosis in the 3 GC lines, but had little effect on the 2 ABC lines. Combination of TL32711 and TRAIL at low concentrations showed marked apoptosis in GC lines, with minimal to no effect for each agent alone. In the combination-treated GC types, caspases -3, -8 and -9 were significantly induced, confirming activation of both pathways. We had previously shown in FSCCL and TxFL2 that caspase-8 induction also cleaved tBID, activating the intrinsic apoptotic pathway via caspase-9. GC subtypes, including FL, transformed FL and GC-DLBCL were sensitive to TRAIL and TL32711 at clinically achievable concentrations for TL32711, with supra-additive combination effects. ABC-type DLBCL were not sensitive to either agent alone or in combination. We are investigating whether ABC-DLBCL are truly dependent on canonical NF-κB activation for survival or have other mechanisms of resistance to TRAIL and IAP inhibition. These data suggest that clinical trials of TL32711 may focus on FL and GC lymphoma in combination with TRAIL or TRAIL-agonists.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3857. doi:1538-7445.AM2012-3857

Brentuximab vedotin in anaplastic large cell lymphoma

INTRODUCTION

Brentuximab vedotin , a novel anti-CD30 antibody-drug conjugate, delivers a cytotoxic agent into CD30(+) cells. CD30 expression is characteristic of anaplastic large cell lymphoma (ALCL) and Hodgkin lymphoma (HL).

AREAS COVERED

We reviewed data on brentuximab vedotin, focusing on ALCL and discuss pharmacology, clinical trials leading to approval and future research directions. Systemic ALCL, 3% of adult NHL, is characterized by large anaplastic CD30(+) cells. The fusion protein NPM-ALK, when present in systemic ALCL, confers better prognosis, although even ALK- patients with IPI score ≥ 3 are high-risk. For patients with systemic ALCL, 25 - 45% relapse after frontline therapy, and > 50% of patients will relapse following high-dose chemotherapy with autologous stem-cell support. There has been no standard therapy for relapsed/refractory systemic ALCL. Brentuximab vedotin, combines a monoclonal antibody targeted to CD30 with a microtubule disrupting agent and was recently approved for treatment of patients with systemic ALCL that is refractory or relapsed after at least one multiagent chemotherapy regimen.

EXPERT OPINION

Brentuximab vedotin provides targeted therapy to CD30(+) lymphomas, including ALCL and HL, with high response rates and manageable toxicity, predominantly myelosuppression and peripheral neuropathy.

Results of a phase 1 study of AME-133v (LY2469298), an Fc-engineered humanized monoclonal anti-CD20 antibody, in FcγRIIIa-genotyped patients with previously treated follicular lymphoma

PURPOSE

AME-133v is a humanized monoclonal antibody engineered to have increased affinity to CD20 and mediate antibody-dependent cell-mediated cytotoxicity (ADCC) better than rituximab. Safety, pharmacokinetics, and efficacy were assessed in a phase 1/2 trial in patients with previously treated follicular lymphoma (FL).

PATIENTS AND METHODS

AME-133v was characterized in vitro by ADCC and cell binding assays. A phase 1 study was conducted in which 23 previously treated patients with FL were assigned sequentially to one of five dose-escalation cohorts of AME-133v at 2, 7.5, 30, 100, or 375 mg/m(2) weekly × 4 doses.

RESULTS

AME-133v showed a 13- to 20-fold greater binding affinity for CD20 and was 5- to 7-fold more potent than rituximab in ADCC assays. Cell binding assays showed AME-133v and rituximab competed for an overlapping epitope on the CD20 antigen, and AME-133v inhibited binding of biotinylated rituximab to CD20 in a concentration-dependent manner. AME-133v was well tolerated by patients and common related adverse events included chills and fatigue. One patient experienced a dose-limiting toxicity of neutropenia. AME-133v showed nonlinear pharmocokinetics with properties similar to rituximab. Selective reduction of B cells during and after AME-133v treatment was shown by flow cytometry of peripheral blood. A partial or complete response was observed in 5 of 23 (22%) patients and the median progression-free survival was 25.4 weeks.

CONCLUSIONS

AME-133v was safe and well tolerated at the doses tested. AME-133v showed encouraging results as an anti-CD20 therapy in heavily pretreated FL patients with the less favorable FcγRIIIa F-carrier genotype.

Directional limits on persistent gravitational waves using LIGO S5 science data

The gravitational-wave (GW) sky may include nearby pointlike sources as well as stochastic backgrounds. We perform two directional searches for persistent GWs using data from the LIGO S5 science run: one optimized for pointlike sources and one for arbitrary extended sources. Finding no evidence to support the detection of GWs, we present 90% confidence level (C.L.) upper-limit maps of GW strain power with typical values between 2-20×10(-50)  strain(2) Hz(-1) and 5-35×10(-49)  strain(2) Hz(-1) sr(-1) for pointlike and extended sources, respectively. The latter result is the first of its kind. We also set 90% C.L. limits on the narrow-band root-mean-square GW strain from interesting targets including Sco X-1, SN 1987A and the Galactic center as low as ≈7×10(-25) in the most sensitive frequency range near 160 Hz.