Phase I/II Study of an Anti-CD30 Monoclonal Antibody (MDX-060) in Hodgkin's Lymphoma and Anaplastic Large-Cell Lymphoma

A Phase II trial of the oral mTOR inhibitor everolimus in relapsed Hodgkin lymphoma

Everolimus is an oral antineoplastic agent that targets the raptor mammalian target of rapamycin (mTORC1). The phosphatidylinositol 3-kinase/mTOR signal transduction pathway has been demonstrated to be activated in tumor samples from patients with Hodgkin lymphoma (HL). The goal of this trial was to learn the antitumor activity and toxicity of everolimus in patients with relapsed/refractory HL. Patients were eligible if they had measurable disease, a platelet count >75,000, and an absolute neutrophil count >1,000. Patients received everolimus 10 mg PO daily. Dose reductions were allowed. Response was assessed after two and six cycles and then every three cycles until progression. Patients could remain on drug until progression or toxicity. Nineteen patients were enrolled. Median age was 37 years (range, 27-68). Patients had received a median of six prior therapies (range, 3-14) and 84% had undergone prior autologous stem cell transplant. The ORR was 47% (95% CI: 24-71%) with eight patients achieving a PR and one patient achieving a CR. The median TTP was 7.2 months. Four responders remained progression free at 12 months. Patients received a median of seven cycles of therapy. Of the 19 patients, one remains on therapy at 36 months; the others went off study because of progressive disease (16), toxicity (1), and death from infection (1). Four patients experienced a Grade 3 or higher pulmonary toxicity. Everolimus has single-agent activity in relapsed/refractory HL and provides proof-of-concept that targeting the mTOR pathway in HL is clinically relevant.

Current approaches to the management of pediatric Hodgkin lymphoma

Hodgkin lymphoma is one of the few cancers that affect both adults and children. Cure rates for Hodgkin lymphoma remain among the best for pediatric cancers. However, cure is often associated with significant delayed effects of therapy, including an elevated risk for second malignancies, cardiotoxicity, pulmonary toxicity, and gonadal and non-gonadal endocrine dysfunction. Therefore, the aim of current treatment strategies is to further improve outcomes while minimizing therapy-related complications. At diagnosis, patients are classified into risk groups based on disease stage, and the presence of clinical, biologic, and serologic risk factors. In general, the most recent trials have intensified therapy in those patients with high-risk disease to improve disease control, and have limited therapy in those patients with low-risk disease to avoid secondary effects. In low-risk patients, multiple studies have been conducted to investigate limiting either radiation therapy or chemotherapy to prevent long-term side effects without affecting the excellent cure rate. In intermediate- and high-risk patients, many studies have examined intensifying therapy to improve event-free survival rates. In addition, response assessment by fluorine-18-2-fluoro-2-deoxy-D-glucose-positron emission tomography (FDG-PET) may be particularly important in pediatric Hodgkin lymphoma; it may allow modification of treatment to maximize treatment efficacy and minimize late effects of chemotherapy and radiation therapy. Despite the improvements in treatment for all stages of Hodgkin lymphoma, there is still a subgroup of patients who do not enter remission with initial therapy or relapse after initial response to therapy. Unfortunately, standard-dose salvage chemotherapy for relapsed disease has disappointing results in terms of overall survival since patients have typically already received intensive therapy. While there is no standard of care in terms of salvage chemotherapy, high-dose chemotherapy with autologous stem cell transplant (ASCT) rescue has become the standard of care for the majority of children with relapsed Hodgkin lymphoma. The use of allogeneic transplantation is controversial in relapsed or refractory Hodgkin lymphoma; because of the high transplant-related mortality, allogeneic transplant has not been associated with improved overall survival over ASCT. As more has been learned about the biologic mechanisms involved in Hodgkin lymphoma, biologically-based therapies are being investigated for use in this disease, both at initial diagnosis and relapse. Both immunotherapy and small molecules are being studied as possible therapeutic agents in Hodgkin lymphoma. Unfortunately, the vast majority of investigations of novel agents have occurred exclusively in adult patients. However, since pediatric Hodgkin lymphoma and adult Hodgkin lymphoma are similar, these results may potentially be extrapolated to pediatric Hodgkin lymphoma.

Novel therapies for Hodgkin Lymphoma

In recent years, improved understanding of the biology of Hodgkin Lymphoma (HL) has uncovered many potential targets for the treatment of this disease. Clarification of the B-ceLL origin of the Hodgkin Reed Sternberg (HRS) cell and of the complex interactions between the HRS cell and the HL microenvironment have provided new insights into the pathophysiology of HL and identified extracellular and intracellular molecules which are essential for HRS survival. New agents directed at these molecules are now in early phase clinical trials.

Constitutively overexpressed 21 kDa protein in Hodgkin lymphoma and aggressive non-Hodgkin lymphomas identified as cytochrome B5b (CYB5B)

BACKGROUND

We have previously reported a novel constitutively overexpressed 21 kDa protein in Hodgkin Lymphoma (HL) and aggressive Non-Hodgkin Lymphomas (NHL). The objective of the current study was to 1) identify this protein using two independent methods, 2) study the expression of the protein and its encoding mRNA in reactive lymph nodes, normal lymphocytes and CD34+ bone marrow precursor cells, 3) analyse patterns of expression of the protein in tissue microarrays assembled from a large number of diagnostic clinical biopsies from patients with HL, and 4) determine the copy number variation and mutation status of the encoding gene in HL cell lines.

RESULTS

Peptide sequencing by LC-MS/MS and protein identification by protein array screening identified a single protein, CYB5B. No mutations were detected in the CYB5B gene in HL cell lines. Quantitative PCR showed CYB5B gene expression was increased in HL and NHL cell lines. Array CGH using a submegabase resolution tiling array revealed gains in the CYB5B locus in HL cell lines KMH2 and L428. Membrane expression was seen in Reed-Sternberg cells in clinical biopsies from patients with HL but not in reactive lymph nodes. Bone marrow CD34+ precursor cells were CYB5B negative on the cell surface. RT-PCR assays of RNA extracted from T and B cell enriched fractions obtained from normal peripheral blood mononuclear cells, reactive lymph nodes, tonsils and normal bone marrow samples showed no evidence of increased mRNA levels of CYB5B in comparison to housekeeping gene GAPDH.

CONCLUSIONS

The 21 kDa protein overexpressed in HL and aggressive NHL is identical to CYB5B. CYB5B gene expression is increased in a subset of HL and NHL cell lines tested. This is associated with CYB5B gene amplification in HL cell lines KMH2 and L428. CYB5B may be a potential target for antibody-based therapy of HL and aggressive NHL as although cytoplasmic expression is present in reactive lymphocytes, it is not expressed on the cell surface of non-neoplastic lymphocytes or bone marrow precursor cells.

High-dose chemo-radiotherapy for relapsed or refractory Hodgkin lymphoma and the significance of pre-transplant functional imaging

We previously reported that three risk factors (RF): initial remission duration <1 year, active B symptoms, and extranodal disease predict outcome in relapsed or refractory Hodgkin lymphoma (HL). Our goal was to improve event-free survival (EFS) for patients with multiple RF and to determine if response to salvage therapy impacted outcome. We conducted a phase II intent-to-treat study of tailored salvage treatment: patients with zero or one RF received standard-dose ifosfamide, carboplatin, and etoposide (ICE); patients with two RF received augmented ICE; patients with three RF received high-dose ICE with stem cell support. This was followed by evaluation with both computed tomography and functional imaging (FI); those with chemosensitive disease underwent high-dose chemoradiotherapy and autologous stem cell transplantation (ASCT). There was no treatment-related mortality. Compared to historical controls this therapy eliminated the difference in EFS between the three prognostic groups. Pre-ASCT FI predicted outcome; 4-year EFS rates was 33% vs. 77% for patients transplanted with positive versus negative FI respectively, P = 0.00004, hazard ratio 4.61. Risk-adapted augmentation of salvage treatment in patients with HL is feasible and improves EFS in poorer-risk patients. Our data suggest that normalisation of FI pre-ASCT predicts outcome, and should be the goal of salvage treatment.

Upcoming diagnostic and therapeutic developments in classical Hodgkin's lymphoma

With improvements in therapy, increasing dose intensity, early recognition of toxicity, and enhanced supportive care, current outcomes in patients with classical Hodgkin's lymphoma (HL) may be superior to disease-free and overall survival (OS) predicted by existing prognostic models, including the International Prognostic Score (IPS). The addition of biologic markers to recognized clinical prognostic factors, including those of the IPS, may to improve patient risk stratification and guide therapy in the future. However, the identification of these markers has been problematic due to the lack of large, confirmatory prospective trials, reproducibility and feasibility of the assays, and failure to improve upon already recognized clinical risk factors. One biomarker in particular, CD68, present on tumor infiltrating macrophages and detectable by immunohistochemical staining, is significantly associated with both shortened progression-free and disease-specific survivals in patients with HL at diagnosis and at relapse. In addition, less than 5% CD68+ cells correlates with a 100% disease-specific survival in patients with early-stage HL. CD68 represents just one of the many prognostic markers that could eventually be used to risk-stratify therapy. In addition, biologic markers may not only serve as prognostic markers, but also as therapeutic targets in HL. This review examines current data using the IPS to determine patient outcome, discuss several potential biologic prognostic markers, and summarize new therapies that are currently in clinical development in HL.

Susceptibility of human T-cell leukemia virus type I-infected cells to humanized anti-CD30 monoclonal antibodies in vitro and in vivo

Adult T-cell leukemia (ATL) is an aggressive malignancy of activated CD4(+) T cells associated with human T-cell leukemia virus type I (HTLV-I) infection. No conventional chemotherapy regimen has appeared successful in patients with ATL, thus establishing effective therapy is urgently required. In some cases, ATL tumor cells express CD30 on the cell surface, therefore, a therapy with mAb against CD30 would be beneficial. To investigate the effect of CD30-mediated therapy on ATL, we assessed SGN-30, a chimeric anti-CD30 mAb, and SGN-35, a monomethyl auristatin E-conjugated anti-CD30 mAb, in vitro and in vivo. Three HTLV-I-infected cell lines were co-cultured with SGN-30 or SGN-35, and the growth-inhibitory effects on the HTLV-I-infected cells were evaluated using an in vitro cell proliferation assay and cell cycle analysis. SGN-30 and SGN-35 showed growth-inhibitory activity against the HTLV-I-infected cell lines by apoptosis and/or cell growth arrest in vitro. To further investigate the effects of SGN-30 and SGN-35 on HTLV-I-infected cells in vivo, we used NOD/SCID mice subcutaneously engrafted with HTLV-I-infected cells. Both mAbs significantly inhibited the growth of HTLV-I-infected cell tumors in the NOD/SCID murine xenograft models. These data suggest that CD30-mediated therapy with SGN-30 or SGN-35 would be useful for patients with ATL.

Immunotherapy for epstein-barr virus-related lymphomas

Latent EBV infection is associated with several malignancies, including EBV post-transplant lymphoproliferative disorders (LPD), Hodgkin and non-Hodgkin lymphomas, nasopharyngeal carcinoma and Burkitt lymphoma. The range of expression of latent EBV antigens varies in these tumors, which influences how susceptible the tumors are to immunotherapeutic approaches. Tumors expressing type III latency, such as in LPD, express the widest array of EBV antigens making them the most susceptible to immunotherapy. Treatment strategies for EBV-related tumors include restoring normal cellular immunity by adoptive immunotherapy with EBV-specific T cells and targeting the malignant B cells with monoclonal antibodies. We review the current immunotherapies and future studies aimed at targeting EBV antigen expression in these tumors.

Gemcitabine as single agent in pretreated T-cell lymphoma patients: evaluation of the long-term outcome

BACKGROUND

Peripheral T-cell lymphoma unspecified (PTCLU) and mycosis fungoides (MF) often show resistance to conventional chemotherapy. Gemcitabine should be considered a suitable option. We report the long-term update of 39 pretreated T-cell lymphoma patients treated with gemcitabine.

PATIENTS AND METHODS

From May 1997 to September 2007, 39 pretreated MF and PTCLU patients received gemcitabine. Inclusion criteria were as follows: histologic diagnosis of MF or PTCLU; relapsed/refractory disease; age > or =18 years; and World Health Organization performance status of two or less. Nineteen patients had MF and 20 PTCLU. All patients with MF had a T3-T4, N0, and M0 disease and patients with PTCLU had stage III-IV disease. Gemcitabine was given on days 1, 8, and 15 on a 28-day schedule (1200 mg/m(2)/day) for a total of three to six cycles.

RESULTS

Overall response rate was 51% (20 of 39 patients); complete response (CR) and partial response (PR) rates were 23% (9 of 39 patients) and 28% (11 of 39 patients), respectively. Patients with MF had a CR rate of 16% and a PR rate of 32% compared with a CR rate of 30% and a PR rate of 25% of PTCLU patients. Among the CR patients, 7 of 9 are in continuous complete response with a variable disease-free interval (15-120 months).

CONCLUSION

In our experience, gemcitabine proved to be effective in pretreated MF and PTCLU patients, even in the long term.

Immunotherapy of cancer

Major advances have been made in the field of immunology in the past two decades. A better understanding of the molecular and cellular mechanisms controlling the immune system has opened the door to many innovative and promising new cancer therapies that manipulate the immune response. For instance, toll-like receptor agonists have been shown to boost immune responses toward tumors. Also, a wide array of cell-based immunotherapies utilizing T cells, NK cells, and dendritic cells have been established. Furthermore, a rapidly expanding repertoire of monoclonal antibodies is being developed to treat tumors, and many of the available antibodies have demonstrated impressive clinical responses. Here, we examine some of these immunotherapeutic approaches currently in use or testing to treat cancer, and we examine available evidence with regards to mechanism and efficacy of these treatments.

Hodgkin lymphoma in the elderly: a clinical review of treatment and outcome, past, present and future

Hodgkin lymphoma (HL) is a curable cancer in the vast majority of patients under the age of 60 years. Because of the rarity of the disease in older people, and age related factors such as co-morbidity, inability to tolerate aggressive chemotherapy, poor ECOG status at presentation and issues relating to frailty, the literature is sparse and no prospective randomised studies exist. The incidence of HL in the over 60s range between 10% and 20% of the disease overall and, as a potentially curable cancer, new specific treatment approaches designed for the elderly are necessary. This review discusses the available data in relation to treatments and outcome to date, and proposes how future studies and evaluations might be constructed for this disease. The SHIELD study (Study of Hodgkin lymphoma in the Elderly/Lymphoma Database) is a current example of an approach aimed at objectively defining some of the difficulties of this patient population.

SGN-30: a basis for the effective treatment of CD30 positive hematopoietic malignancies

BACKGROUND

Patients with high-risk, relapsed or refractory Hodgkin lymphoma, those with systemic anaplastic large-cell lymphoma, and those with primary cutaneous CD30-positive disorders are in need of novel therapies. CD30, a common marker in these malignancies, is a reasonable immunologic target given its restricted expression in normal states. SGN-30 is a chimeric antibody targeting CD30.

OBJECTIVE

Review of data regarding SGN-30, including structure, mechanism of action, pharmacokinetics, efficacy in different patient groups, safety, and tolerability.

METHOD

The medical literature and available abstracts regarding SGN-30 are reviewed.

CONCLUSION

SGN-30 may be efficacious through multiple mechanisms of action. The most efficacious dose has yet to be determined. Given the long drug half-life, short infusions may be administered every 2 - 3 weeks. The highest response rate was seen in patients with primary cutaneous CD30-positive lymphoproliferative disease and encouraging results were seen in patients with relapsed or refractory systemic anaplastic large-cell lymphoma. Most responses in Hodgkin lymphoma were stable disease. Despite a majority of patients having had stem cell transplantation, the drug was well tolerated. There are in vivo and in vitro data that SGN-30 may be synergistic with chemotherapy.

Novel treatment strategies for patients with relapsed classical Hodgkin lymphoma

Although classical Hodgkin lymphoma (HL) is considered one of the most curable human cancers, the treatment of patients with relapsed and refractory disease, especially those who relapse after autologous stem cell transplantation, remains challenging. Furthermore, because the median age of the patients is in the mid-30s, the impact of early mortality on the number of years lost from productive life is remarkable. Patients with HL whose disease relapses after stem cell transplantation are rarely cured with current treatment modalities. New drugs and novel treatment strategies that are based on our understanding of the disease biology and signaling pathways are needed to improve treatment outcome for these patients. This review will focus on emerging new treatment modalities that are currently under investigation for patients with relapsed classical HL.

Novel antibody approaches for T-cell lymphomas

T-cell lymphomas are biologically more aggressive--and less responsive than their B-cell counterparts--to conventional chemotherapy. The understanding of the normal physiology of T-cell signaling as well as the pathophysiology of T-cell neoplasia has advanced dramatically in the past decade. Thus, a number of novel cell surface therapeutic targets specific for T-cells have been identified and evaluated as potential monoclonal antibody (MoAb)-based therapeutic targets. Herein, we review a number of these cell surface targets and discuss the development and the clinical evaluation of MoAb therapies directed against these antigens.

Novel therapies in peripheral T-cell lymphomas

Peripheral T-cell lymphomas (PTCLs) are a rare and heterogeneous group of disorders associated with a very poor prognosis. Historically, treatment protocols have been largely based on regimens used to treat aggressive B-cell lymphomas; unfortunately, the efficacy of these regimens has been suboptimal, with most patients experiencing relapse after initial therapy. An improved understanding of the molecular biology, pathogenesis, and progression of these disorders has led to the development of a variety of novel targeted agents that may improve outcomes in patients with PTCLs. The purpose of this review is to focus on these novel agents and the various treatment approaches that are currently being evaluated in PTCLs.

EBV-associated lymphoproliferative disorders: classification and treatment

Since its discovery as the first human tumor virus, Epstein-Barr virus (EBV) has been implicated in the development of a wide range of B-cell lymphoproliferative disorders, including Burkitt's lymphoma, classic Hodgkin's lymphoma, and lymphomas arising in immunocompromised individuals (post-transplant and HIV-associated lymphoproliferative disorders). T-cell lymphoproliferative disorders that have been reported to be EBV associated include a subset of peripheral T-cell lymphomas, angioimmunoblastic T-cell lymphoma, extranodal nasal type natural killer/T-cell lymphoma, and other rare histotypes. EBV encodes a series of products interacting with or exhibiting homology to a wide variety of antiapoptotic molecules, cytokines, and signal transducers, hence promoting EBV infection, immortalization, and transformation. However, the exact mechanism by which EBV promotes oncogenesis is an area of active debate. The focus of this review is on the pathology, diagnosis, classification, and pathogenesis of EBV-associated lymphomas. Recent advances in EBV cell-based immunotherapy, which is beginning to show promise in the treatment of EBV-related disorders, are discussed.

Regulatory T cells as therapeutic target in Hodgkin's lymphoma

BACKGROUND

The clinical and pathological features of Hodgkin's lymphoma (HL) reflect an abnormal immune response that results from cytokines and chemokines secreted by Hodgkin/Reed-Sternberg (H/R-S) cells and/or the surrounding tissue.

OBJECTIVE

Increasing evidence indicates that H/R-S cells recruit and/or induce regulatory T (Treg) cells that contribute to an ineffective immune clearance of the malignant cell types and may also impair effects of adaptive cellular immunotherapy applied in HL.

METHODS

In this review we highlight advances in the understanding of immune regulation in HL, and discuss implications for immunotherapy in this disease by targeting Treg cells. However, the origin, development, migration and functional mechanism of these Treg cells are under discussion.

RESULTS/CONCLUSION

As studies demonstrate that the depletion and/or manipulation of Treg cells enhance antitumor immunity, these novel treatment approaches may improve the therapy especially for patients with refractory or relapsed HL.

Recombinant antibodies for cancer therapy

BACKGROUND

Recombinant antibodies have evolved into successful therapeutics with 10 approved for cancer and more in the pipeline. Four of the top ten cancer therapy drugs are recombinant antibodies.

OBJECTIVES

To survey the current state-of-the-art highlighting the reasons for this success and looking ahead to the next generation of antibody therapy.

METHODS

An analysis was carried out to identify preclinical and clinical examples and the underlying concepts and mechanisms that have shown how to design better therapies.

RESULTS/CONCLUSIONS

Greater understanding of the molecular basis of cancer has led to improved antibodies and a greater selection of targets. Fine tuning of successful antibodies through modification of glycosylation, affinity, size and other parameters are paying dividends. Fc-engineering is likely to be predominant in the near future but conjugates, fragments and fusion proteins will continue to be developed and find their place in the arsenal of antibody therapeutics.

Modern treatment of Hodgkin lymphoma

PURPOSE OF REVIEW

The present review summarizes the current therapies and controversies in the management of newly diagnosed and relapsed classical and lymphocyte predominant Hodgkin lymphoma and briefly describes novel agents in development for Hodgkin lymphoma.

RECENT FINDINGS

Early restaging fluoro-2-deoxy-D-glucose-positron emission tomography scans appear to provide important prognostic information, particularly in patients with advanced stage Hodgkin lymphoma. A persistently positive scan after two cycles of chemotherapy appears to predict a very dismal outcome, whereas a negative interim scan predicts a very favorable outcome. This finding provides an opportunity to study the effect of tailoring therapy early in the course of disease, perhaps shortening therapy and avoiding radiotherapy in early stage patients with a negative interim scan and escalating therapy in those with positive scans. Recent retrospective studies show it is safe to administer the standard doxorubicin, bleomycin, vinblastine, dacarbazine chemotherapy regimen, prescribed for nearly all patients with Hodgkin lymphoma, at full dose, on schedule without growth factors, minimizing the risk of bleomycin lung toxicity and perhaps improving outcome. Several new drugs are showing promise for refractory Hodgkin lymphoma, including the immunotoxin SGN-35 and the histone deacetylase inhibitor MGCD0103. Rituximab is being studied for the treatment of both classical and lymphocyte predominant Hodgkin lymphoma.

SUMMARY

Current trials employing risk-adapted therapy on the basis of interim fluoro-2-deoxy-D-glucose-positron emission tomography scans have the potential of improving outcomes for all patients with Hodgkin lymphoma, either by improving cure rates, minimizing toxicity, or both.

Manipulating B cell homeostasis: a key component in the advancement of targeted strategies

Understanding the homeostatic mechanisms governing lymphocyte pools achieves critical importance as lymphocyte-targeted therapies expand in use and scope. The primacy of B lymphocyte stimulator (BLyS) family ligands and receptors in governing B lymphocyte homeostasis has become increasingly clear in recent years, affording insight into novel opportunities and potential pitfalls for targeted B cell therapeutics. Interclonal competition for BLyS-BR3 interactions determines the size of naïve B cell pools and can regulate the stringency of selection applied as cells complete maturation. Thus one of the predicted consequences of ablative therapies targeting primary pools is relaxed negative selection. This suggests that BLyS levels and B cell reconstitution rates may serve useful prognostic roles and that BLyS itself might be targeted to circumvent relapse. Alternatively, manipulations that allow rare, minimally autoreactive specificities to survive and mature may lead to opportunities in cases where antibody-based vaccine development has heretofore been unsuccessful. BLyS family ligands and receptors also play a role in activated and memory B cell pools, suggesting they might likewise be targeted to promote or delete particular antigen-experienced subpopulations in a similar way.

Immunotherapies for Hodgkin's lymphoma

Multiple immune evasion strategies characterize the pathobiology of Hodgkin's lymphoma. These must be considered when developing and testing immunotherapeutic approaches for this disease. The clinical experience with adoptive immunotherapy of Epstein-Barr virus positive tumors, and with monoclonal antibodies directed against CD30, CD20, and other antigens, is herein reviewed.

Receptor-directed therapy of T-cell leukemias and lymphomas

T-Cell leukemias and lymphomas represent a less common and heterogeneous group of lymphoid neoplasms. Overall, they respond less well to chemotherapy and have a poorer prognosis than their B-cell counterparts. T-Cell tumors express a number of potential targets for receptor-directed antibody therapy; however, there is no available therapeutic monoclonal antibody for these diseases with comparable activity to that of rituximab in B-cell disorders. Despite this, alemtuzumab, a humanized anti-CD52 monoclonal antibody has demonstrated meaningful anti-tumor activity in a variety of T-cell malignancies. A number of other antibodies, modified antibodies and immunotoxins directed against targets such as CD2, CD4, CD5, CD25, CD30 and CD122 expressed on malignant T-cells are under investigation. The current status of receptor-directed antibody therapy for T-cell leukemia and lymphoma is reviewed.

A phase 1 multidose study of SGN-30 immunotherapy in patients with refractory or recurrent CD30+ hematologic malignancies

Phase 1 testing of SGN-30, a chimeric monoclonal antibody for the treatment of CD30+ malignancies, was conducted in a multicenter study. To explore the safety profile and establish the maximum tolerated dose (MTD), 24 patients with refractory or relapsed Hodgkin lymphoma or CD30+ non-Hodgkin lymphoma received 6 weekly doses of intravenous SGN-30 at 4 dose levels (2, 4, 8, or 12 mg/kg). Serum concentrations of SGN-30 rose rapidly and were dose dependent. Adverse events were mild, with nausea, fatigue, and fever attributed to study treatment. One episode of hypersensitivity rash was reported. The MTD was not reached. Serious adverse events included herpes zoster (n = 2), influenza, and pneumonia. One patient with cutaneous anaplastic large cell lymphoma (8 mg/kg) achieved a complete response. Six patients, of whom 4 had Hodgkin lymphoma, achieved stable disease with durations ranging from 6 to 16 months. The pharmacokinetic profile of SGN-30 showed a biphasic disposition, and estimated half-lives ranging between 1 to 3 weeks. The 6 weekly infusions of SGN-30 resulted in approximately 2- to 3-fold accumulation in serum exposures consistently across the dose range. These results demonstrate that weekly administration of SGN-30 is safe and has modest clinical activity in patients with CD30+ tumors. This trial is registered at http://www.ClinicalTrials.gov as no. NCT00051597.

CD30-induced signaling is absent in Hodgkin's cells but present in anaplastic large cell lymphoma cells

High CD30 expression in classical Hodgkin's lymphoma and anaplastic large cell lymphoma (ALCL) suggests an important pathogenic role of this cytokine receptor. To test this hypothesis, we investigated CD30 signaling in Hodgkin's and ALCL cell lines by different approaches: 1) CD30 stimulation, 2) CD30 down-regulation, and 3) a combination of both. The effects were determined at the RNA (microarray and real-time quantitative RT-PCR), protein (electrophoretic mobility shift analysis, immunoblot, and flow cytometry), and cellular/functional (proliferation and apoptosis) levels. We demonstrate that Hodgkin's cells are virtually CD30 unresponsive. Neither CD30 stimulation nor CD30 silencing of Hodgkin's cells had any significant effect. In contrast, CD30 stimulation of ALCL cells activated nuclear transcription factor-kappaB (NF-kappaB), induced major transcriptional changes, and decreased proliferation. These effects could be abrogated by down-regulation of CD30. Stimulation of CD30 in ALCL cells, stably transfected with a dominant-negative NF-kappaB inhibitor, induced pronounced caspase activation and massive apoptosis. Our data indicate that 1) CD30 signaling is not effective in Hodgkin's cell lines but is effective in ALCL cell lines, 2) CD30 is probably not significantly involved in the pathogenesis of classical Hodgkin's lymphoma, and 3) CD30 stimulation triggers two competing effects in ALCL cells, namely activation of caspases and NF-kappaB-mediated survival. These data suggest that CD30-targeted therapy in ALCL should be combined with NF-kappaB inhibitors to induce effective cell killing.

Novel Therapies and Role of Transplant in the Treatment of Peripheral T-Cell Lymphomas

Peripheral T-cell lymphomas (PTCL) are an uncommon, heterogeneous group of non-Hodgkin lymphomas that carry a much poorer prognosis than their more common B-cell counterparts. The most commonly used treatment is CHOP or its variations. However, while the results with CHOP are inadequate, there is little compelling data to suggest a preferred alternate strategy. Many of these alternate strategies have been assembled from retrospective data, small case series, subset analyses, phase II studies and individual experience. The greatest experience with alternative treatments has been with the use of high-dose therapy as consolidation. These approaches are promising, but most of the studies are retrospective and include patients with diverse prognoses, making interpretation difficult. Preliminary results of prospective trials in PTCL are only recently being reported. Perhaps more exciting have been the increasing numbers of new therapies being studied for patients with PTCL. The activities of new drugs are being described in studies specifically for PTCL, and attempts at novel combinations are beginning.

Management of Hodgkin lymphoma in relapse after autologous stem cell transplant

Recurrence of Hodgkin lymphoma (HL) occurs in about 50% of patients after autologous stem cell transplantation (ASCT), usually within the first year, and represents a significant therapeutic challenge. The natural history of recurrent HL in this setting may range from a rapidly progressive to a more indolent course. Patients in this setting are often young, without comorbidities and able to tolerate additional therapies: expectations are often still high. The approach to treatment depends on clinical variables (time to relapse, perceived sensitivity to additional cytotoxic therapy, disease stage), prior history of radiation therapy, the availability of an HLA-identical donor, and the availability of new agents via clinical trials. Although very few of these patients can be cured, results from reported series, albeit often small and sometimes with relatively short follow-up, document that excellent disease control can be achieved with radiation, single or multiagent chemotherapy, and reduced-intensity allogeneic transplantation. The results of these approaches will be reviewed, and a treatment algorithm incorporating the use of standard or investigational agents or approaches will be discussed.