A dominant linear B-cell epitope of ricin A-chain is the target of a neutralizing antibody response in Hodgkin's lymphoma patients treated with an anti-CD25 immunotoxin

Hodgkin's lymphoma patients treated with an anti-CD25 Ricin toxin A-chain (RTA)-based Immunotoxin (RFT5.dgA) develop an immune response against the toxic moiety of the immunoconjugate. The anti-RTA antibody response of 15 patients showing different clinical features and receiving different total amounts of RFT5.dgA was therefore studied in detail, considering antibody titre, IgG and IgM content, average binding efficacy and ability to inhibit in vitro the cytotoxicity of a RTA-based Immunotoxin. No correlations were found between these parameters and the clinical features of the patients or the total amount of Immunotoxin administered. However, using a peptide scan approach we have identified a continuous epitope recognized by all patients studied, located within the stretch L161-I175 of the RTA primary sequence, close to a previously identified T-cell epitope. The ability of anti-L161-I175 antibodies to recognize folded RTA and to affect the biological activity of RTA by inhibiting RTA-IT cytotoxicity in vitro revealed that they may exert an important role in IT neutralization in vivo. Discovery of RTA immunodominant epitopes which are the target of anti-RTA immune response may lead to the development of immunomodulating strategies and to more successful treatment schedules.

Treatment of advanced Hodgkin's disease with COPP/ABV/IMEP versus COPP/ABVD and consolidating radiotherapy: final results of the German Hodgkin's Lymphoma Study Group HD6 trial

BACKGROUND

The purpose of this study was to compare the efficacy of the hybrid chemotherapeutic regimen COPP/ABV/IMEP (cyclophosphamide-vincristine-procarbazine-prednisone-doxorubicin-bleomycin-vinblastine-ifosfamide-methotrexate-etoposide) (CAI) with that of the standard regimen COPP/ABVD (COPP/ABV, dacarbacine) (CA) in the treatment of advanced-stage Hodgkin's disease (HD).

PATIENTS AND METHODS

Between January 1988 and January 1993, 588 eligible patients with HD in stages IIIB and IV were randomly assigned to a treatment or control group. The treatment group received four cycles of CAI over a complete cycle duration of 43 days. The control group received four cycles of CA over 57 days. Both groups then received consolidating radiotherapy.

RESULTS

Five hundred and eighty-four patients were suitable for arm comparison. Patients in each group were similar in age, sex, histological subtype and clinical risk factors. Complete remission rates, overall survival and freedom from treatment failure at 7 years were similar for the two groups: 77% versus 78%, 73% versus 73% and 54% versus 56% for CAI and CA, respectively. Differences in acute chemotherapy-related toxicity were significant, however. Prognostic factor analysis confirmed the relevance of the International Prognostic Index and revealed that stage IVB, low hemoglobin, low lymphocyte count, high age and male gender were associated with a poor prognosis

CONCLUSION

The rapidly alternating hybrid CAI did not give superior results when compared with the standard regimen CA in advanced-stage HD.

Granulopoiesis-stimulating factors to prevent adverse effects in the treatment of malignant lymphoma

BACKGROUND

Granulopoiesis-stimulating factors, such as granulocyte-colony-stimulating factor (G-CSF) and granulocyte-macrophage-colony-stimulating factor (GM-CSF), are being used to prevent febrile neutropenia and infection in patients undergoing treatment for malignant lymphoma. The question of whether G-CSF and GM-CSF improve dose intensity, tumour response, and overall survival in this patient population has not been answered yet. Since the results from single studies are inconclusive, a systematic review was undertaken.

OBJECTIVES

To determine the effectiveness of G-CSF and GM-CSF in patients with malignant lymphoma with respect to preventing neutropenia, febrile neutropenia and infection; improving quality of life, adherence to treatment protocol, tumour response, freedom from treatment failure (FFTF) and overall survival (OS); and adverse effects.

SEARCH STRATEGY

We searched The Cochrane Library, MEDLINE, EMBASE, CancerLit, and other relevant literature databases; internet databases of ongoing trials; and conference proceedings of the American Society of Clinical Oncology and the American Society of Hematology (1980 - 2003). We included full-text and abstract publications as well as unpublished data.

SELECTION CRITERIA

Randomised controlled trials comparing prophylaxis with G-CSF or GM-CSF versus placebo/no prophylaxis in adult patients with malignant lymphoma undergoing chemotherapy were included for review. Both study arms had to receive identical chemotherapy and supportive care.

DATA COLLECTION AND ANALYSIS

Trial eligibility and quality assessment, data extraction and analysis were done in duplicate. Authors were contacted to obtain missing data.

MAIN RESULTS

We included 12 eligible randomised controlled trials with 1823 patients. Compared with no prophylaxis, both G-CSF and GM-CSF significantly reduced the relative risk (RR) for severe neutropenia (RR 0.67; 95% confidence interval (CI) 0.60 to 0.73), febrile neutropenia (RR 0.74; 95% CI 0.62 to 0.89) and infection (RR 0.74; 95% CI 0.64 to 0.85). There was no evidence that either G-CSF or GM-CSF reduced the number of patients requiring intravenous antibiotics (RR 0.82; 95%CI 0.57 to 1.18); lowered infection related mortality (RR 1.37; 95% CI 0.66 to 2.82); or improved complete tumour response (RR 1.02; 95% CI 0.94 to 1.11), FFTF (hazard ratio 1.11; 95% CI 0.91 to 1.35) and OS (hazard ratio 1.00; 95% CI 0.86 to 1.16). One study evaluated quality of life parameters and found no differences between the treatment groups.

REVIEWERS' CONCLUSIONS

G-CSF and GM-CSF, when used as a prophylaxis in patients with malignant lymphoma undergoing conventional chemotherapy, reduce the risk of neutropenia, febrile neutropenia and infection. However, based on the randomised trials currently available, there is no evidence that either G-CSF or GM-CSF provide a significant advantage in terms of complete tumour response, FFTF or OS.

Erythropoietin for patients with malignant disease

BACKGROUND

Anaemia associated with cancer and cancer therapy is an important clinical factor in the treatment of malignant diseases. Therapeutic alternatives are recombinant human erythropoietin (EPO) and red blood cell transfusions.

OBJECTIVES

The aim of this systematic review was to assess the effect of erythropoietin to either prevent or treat anaemia in cancer patients.

SEARCH STRATEGY

We searched the Central Register of Controlled Trials, MEDLINE (01/1985 to 12/2001), EMBASE (01/1985 to 12/2001), other databases and reference lists of articles. We also contacted experts in the field and pharmaceutical companies.

SELECTION CRITERIA

Randomised controlled trials comparing the use of recombinant human erythropoietin (plus transfusion if needed) with red blood cell transfusions alone for the treatment or prevention of anaemia in cancer patients.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed trial quality and extracted data. All authors from included studies were contacted for additional information.

MAIN RESULTS

Twenty seven trials with 3,287 adults were included. Use of erythropoietin significantly reduced the relative risk of red blood cell transfusions (RR 0.67; 95% CI 0.62 to 0.73, 25 trials, n = 3,069). On average participants in the erythropoietin group received one unit of blood less than the control group (WMD -1.00; 95% CI-1.31 to -0.70, 13 trials, n = 2,056). For participants with baseline haemoglobin below 10 g/dL haematological response was observed more often in participants receiving EPO (RR 3.60; 95% CI 3.07 to 4.23, 14 trials, n = 2,347). There was inconclusive evidence whether EPO improves tumour response (fixed effect RR 1.36; 95% CI 1.07 to 1.72, seven trials, n = 1,150; random effects: RR 1.21; 95% CI 0.92 to 1.59) and overall survival (adjusted data: HR 0.81; 95% CI 0.67 to 0.99; unadjusted data: HR 0.84; 95% CI 0.69 to 1.02, 19 trials, n = 2,865). There were no statistically significant adverse effects. Evidence was inconclusive with respect to quality of life and fatigue.

REVIEWERS' CONCLUSIONS

There is consistent evidence that the administration of erythropoietin reduces the risk for blood transfusions and the number of units transfused in cancer patients. For patients with baseline haemoglobin below 10 g/dL there is strong evidence that erythropoietin improves haematological response. There is inconclusive evidence whether erythropoietin improves tumour response and overall survival. Research on side effects is inconclusive.

Moderne Pharmakotherapie des Morbus Hodgkin

High cure rates have been achieved in the treatment for patients with Hodgkin's disease in the past 30 years. Depending on stage at diagnosis and further risk factors up to 95% of patients with Hodgkin's disease can be cured with first-line treatment. Modern therapeutic strategies aim at both reducing therapy-induced late toxicities while maintaining effective tumor control. Patients with early stage Hodgkin's disease are now treated with a short course of chemotherapy for control of occult disease and involved field (IF) irradiation. For patients with early unfavourable stages, effectiveness of treatment shall be optimised by introducing the escalated BEACOPP schedule which has been established in the treatment of advanced stages. Questions to be answered in the treatment of advanced stages concern the optimal number of cycles of an effective chemotherapy regimen and the necessity of additional radiation therapy. The role of erythropoetin and PET-imaging is currently being evaluated in ongoing trials. In the future, new therapeutic approaches with biological agents will be of interest.

Granulopoiesis-stimulating factors to prevent adverse effects in the treatment of malignant lymphoma

BACKGROUND

Granulopoiesis-stimulating factors (G-CSF and GM-CSF) are being used to prevent febrile neutropenia and infections in the treatment of patients with malignant lymphoma. The question whether G-CSF and GM-CSF improve dose-intensity, tumour response and overall survival in this patient population has not been answered yet. Since the results from single studies are inconclusive a systematic review was required.

OBJECTIVES

To undertake a systematic review in patients with malignant lymphoma to determine the effectiveness of G-CSF and GM-CSF to prevent neutropenia, febrile neutropenia, infection, improve quality of life, adherence to the treatment protocol, tumour response, freedom from treatment failure (FFTF), overall survival (OS) and to assess adverse events of G-CSF and GM-CSF.

SEARCH STRATEGY

Medline, Embase, CancerLit, the Cochrane Library and smaller databases, Internet-databases of ongoing trials, conference proceedings of the American Society of Clinical Oncology and the American Society of Hematology were searched. We included full-text and abstract publications as well as unpublished data.

SELECTION CRITERIA

Randomised controlled trials comparing prophylaxis with G-CSF or GM-CSF versus placebo/no prophylaxis in adult patients with malignant lymphoma undergoing chemotherapy were included in this review. Both study arms had to receive identical chemotherapy and supportive care.

DATA COLLECTION AND ANALYSIS

Eligibility and quality assessment, data extraction and analysis were done in duplicate. Authors were contacted to obtain missing data.

MAIN RESULTS

We included 12 eligible studies with 1.823 randomised patients. Compared with no prophylaxis, G-/GM-CSF significantly reduced the relative risk for severe neutropenia (RR 0.67 [95% CI 0.60-0.73]), febrile neutropenia (RR 0.74 [95% CI 0.62-0.89]) and infection (RR 0.74 [95% CI 0.64-0.85]). There was no evidence for G-/GM-CSF to decrease the number of patients who required iv antibiotics (RR 0.82 [95%CI 0.57-1.18]), to reduce infection related mortality (RR 1.37 [95% CI 0.66-2.82]), or to improve complete tumour response (RR 1.02 [95% CI 0.94-1.11]), FFTF (HR 1.11 [95% CI 0.91-1.35]) and OS (HR 1.00 [95% CI 0.86-1.16]). One study evaluated quality of life parameters and did not find differences between the groups.

REVIEWER'S CONCLUSIONS

G-CSF and GM-CSF, when given prophylactically in patients with malignant lymphoma undergoing conventional chemotherapy, reduce the risk of neutropenia, febrile neutropenia and infection. However, based on the currently available randomised trials in this clinical setting, there is no evidence for G-/GM-CSF to provide a significant advantage in terms of complete tumour response, FFTF and OS.

Combination therapy of disseminated Fusarium oxysporum infection with terbinafine and amphotericin B

A case of disseminated infection with Fusarium oxysporum following chemotherapy of acute myelogenous leukemia is reported. Antifungal treatment was successful with a 13-day course of oral terbinafine 250 mg t.i.d. in combination with amphotericin B deoxycholate 1.0-1.5 mg/kg qd and subsequently intravenous liposomal amphotericin B 5 mg/kg qd. Preceding monotherapy with amphotericin B deoxycholate 1.0-1.5 mg/kg qd had not stopped the progression of infection. The combination therapy described here represents a novel approach to the treatment of Fusarium spp. in the immunocompromised host in whom Fusarium spp. are known to cause disseminated infection with high mortality.

Recombinant human erythropoietin, epoetin beta, in patients with relapsed lymphoma treated with aggressive sequential salvage chemotherapy--results of a randomized trial

The aim of the study was to investigate the effects of erythropoietin (epoetin beta) on red blood cell (RBC) transfusions, hemoglobin (Hb) levels, and quality of life (QOL) in patients with relapsed lymphoma treated with an aggressive sequential salvage chemotherapy (SSCT) regimen. Sixty patients with early or late relapsed Hodgkin's disease ( n=39) or first relapse of aggressive non-Hodgkin's lymphoma ( n=21) were randomized to receive epoetin beta 10,000 IE subcutaneously three times a week or no epoetin during salvage chemotherapy. Patients in both study arms received two cycles of DHAP (dexamethasone, high-dose cytarabine, cisplatin); patients in partial remission (PR) or complete remission (CR) then received cyclophosphamide, followed by peripheral blood stem cell (PBSC) harvest, methotrexate plus vincristine, and etoposide. The final myeloablative course was BEAM (carmustine, etoposide, cytarabine, and melphalan) followed by autologous stem cell support. The primary endpoint of the study was the number of RBC units needed during SSCT. In addition, Hb levels and QOL were measured. The mean number of RBC units given in the epoetin beta arm was 4.5 compared to 8.3 in the control arm ( P=0.0134). The mean Hb levels during therapy were 10.4 g/dl in the epoetin beta arm and 9.7 g/dl in the control ( P=0.018). From baseline until BEAM therapy QOL (EORTC QLQ C30) and fatigue (MFI) assessment showed little QOL worsening or stable levels in both arms with a steeper increase of fatigue levels in the control group. Patients with relapsed lymphoma undergoing aggressive chemotherapy and stem cell support benefited from epoetin beta therapy, with a decrease of RBC transfusion requirements and lower rise of fatigue levels.

Treatment of CNS lymphoma with the anti-CD20 antibody rituximab: experience with two cases and review of the literature

Treatment with radio- and chemotherapy has become increasingly efficient in primary CNS lymphoma (PCNSL). However, time to tumor progression is often short, and the majority of patients eventually relapse. Therefore, new therapeutic modalities are needed. One possible new option is the use of monoclonal antibodies (moabs) such as the humanized anti-CD20 moab rituximab. Treatment with intravenous rituximab has resulted in response rates of 50% in systemic non-Hodgkin's lymphoma and was also efficient in PCNSL as well as in CNS involvement of systemic disease. However, rituximab concentrations in the cerebrospinal fluid are low after systemic application. Therefore, the authors performed an intraventricular rituximab treatment in 2 patients. The most recent results and the possible role of moabs in patients with PCNSL are summarized and discussed.

14-day variant of the bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone regimen in advanced-stage Hodgkin's lymphoma: results of a pilot study of the German Hodgkin's Lymphoma Study Group

PURPOSE

This multicenter pilot study assessed the feasibility and efficacy of a time-intensified bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone (BEACOPP) regimen given in 14-day intervals (BEACOPP-14) with granulocyte colony-stimulating factor (G-CSF) support in advanced Hodgkin's lymphoma.

PATIENTS AND METHODS

From July 1997 until March 2000, 94 patients with Hodgkin's lymphoma stage IIB, III, and IV were scheduled to receive eight cycles of BEACOPP-14. Consolidation radiotherapy was administered to regions with initial bulky disease or residual tumor after chemotherapy.

RESULTS

All patients were assessable for toxicity and treatment outcome. Eighty-six patients received the planned eight cycles of BEACOPP-14. Consolidation radiotherapy was given in 66 patients. Chemotherapy could generally be administered on schedule. Dose reductions varied among drugs but were generally low. Acute toxicity was moderate, with World Health Organization grade 3/4 leukopenia in 75%, thrombocytopenia in 23%, anemia in 65%, and infection in 12% of patients. A total of 88 patients (94%) achieved a complete remission. Four patients had progressive disease. At a median observation time of 34 months, five patients have relapsed, one patient developed a secondary non-Hodgkin's lymphoma, and three deaths were documented. The overall survival and freedom from treatment failure rates at 34 months were 97% (95% confidence interval [CI], 93% to 100%) and 90% (95% CI, 84% to 97%), respectively.

CONCLUSION

Acceleration of the BEACOPP baseline regimen by shortening cycle duration with G-CSF support is feasible and effective with moderate acute toxicity. On the basis of these results, the German Hodgkin's Lymphoma Study Group will compare the BEACOPP-14 regimen with BEACOPP-21 escalated in a prospective multicenter randomized trial.

Clinical evaluation of ricin A-chain immunotoxins in patients with Hodgkin's lymphoma

BACKGROUND

Immunotoxins (ITs) consist of cell binding ligands coupled to toxins or their subunits. Hodgkin's lymphoma (HL) is an excellent target for ITs since lymphocyte activation markers such as CD25 and CD30 are expressed in large numbers. The ITs RFT5.dgA (anti CD25) and Ki-4.dgA (anti CD30) were constructed by linking the monoclonal antibodies RFT5 and Ki-4 to deglycosylated ricin A-chain (dgA). Both ITs showed potent specific activity against HL cells in vitro and in vivo in animal models, and were subsequently evaluated in phase I/II clinical trials in humans.

PATIENTS AND METHODS

In two separate trials, the ITs were administered i.v. four times every other day over 4 h. The objectives of the phase I trials included the determination of the maximum tolerated dose (MTD), dose-limiting toxicities (DLTs), pharmacokinetics, antitumor activity and immune response against the IT.

RESULTS

Twenty-seven patients with refractory HL were included in the phase I/II study of RFT5.dgA and 17 patients were included in the phase I study of Ki-4.dgA. The MTD of RFT5.dgA was 15 mg/m(2), whereas that of Ki-4.dgA was 5 mg/m(2). DLTs were related to vascular leak syndrome, consisting of edema, tachycardia, dyspnea, weakness and myalgia. Measurement of serum levels of RFT5.dgA demonstrated a C(max) of 0.2-9.7 micro g/ml with a half-life (t()) varying from 4 to 10.5 h. Peak serum concentration of Ki-4.dgA ranged from 0.23 to 1.7 micro g/ml. In both trials approximately 60% of patients developed human anti-mouse and/or anti-dgA antibodies. Seventeen of 18 patients treated at the MTD of RFT5.dgA were evaluable for clinical response. Responses included two partial remissions (PR), one minor response (MR) and five stable diseases (SD). Fifteen of 17 patients treated with Ki-4.dgA were evaluable for clinical response. Responses included one PR, one MR and two SD.

CONCLUSIONS

RFT5.dgA and Ki-4.dgA showed moderate efficacy in heavily pretreated refractory patients with HL. Ki-4.dgA was less well tolerated than RFT5.dgA. This might be due, at least in part, to the formation of Ki-4.dgA/sCD30 complexes.

Intraventricular and intravenous treatment of a patient with refractory primary CNS lymphoma using rituximab

The treatment of primary central nervous system lymphoma (PCNSL) with chemo- and radiotherapy is efficient in terms of tumor response. However, time to tumor progression often is of short duration and leptomeningeal relapse is common. We present a 66-year-old man in third relapse of a CD20-positive PCNSL. After treatment with intravenous and intraventricular administration of the chimeric anti-CD20 monoclonal antibody rituximab, a total clearing of lymphoma cells in the cerebrospinal fluid (CSF) was achieved. There was no change in the size of the parenchymal tumor mass but there was slight improvement of clinical symptoms after therapy. Rituximab infusions (375 mg/m2) were first given systemically on days 1 and 8. Intraventricular injections of rituximab via Ommaya reservoir were given on days 16 (10 mg), 17 (40 mg), 24 (25 mg) and 25 (25 mg). Reversible side effects such as nausea, chills and hypotension were observed only immediately after intraventricular administration of 40 mg rituximab. Antibody levels in CSF were measured at 7 timepoints during and after the treatment period. These data suggest that intraventicular treatment with rituximab is safe and feasible with a potential activity on leptomeningeal tumor manifestation. Efficacy and pharmacokinetics of rituximab in PCNSL should be investigated in future trials.

Clinical applications of granulocyte colony-stimulating factor: an update and summary

The discovery of granulocyte colony-stimulating factor (G-CSF) and its potential to regulate neutrophil production and function in the inflammatory process has opened an exciting new era for the supportive care of patients with hematological and malignant diseases. Extensive experience has been gained worldwide with G-CSF therapy, and G-CSF is widely employed clinically, primarily because the safety profile appears to be fairly innocuous. A broad consensus has emerged regarding the clinical utility of G-CSF in neutropenic conditions due to chemotherapy. Furthermore, much interest has focused on the use of G-CSF to mobilize CD34+ hematopoietic stem cells from the marrow to the peripheral blood for use in hematopoietic transplantation. The promising results with G-CSF have promoted further studies, e.g., in immunocompetent patients or in granulocyte transfusion therapy. Here, we review the potential clinical role of G-CSF and describe its future perspectives.

An overview of the current clinical use of the anti-CD20 monoclonal antibody rituximab

The chimeric anti-CD20 monoclonal antibody rituximab has become part of the standard therapy for patients with non-Hodgkin's lymphoma (NHL). To date, more than 300 000 patients have been treated with rituximab worldwide, including patients with indolent and aggressive NHL, Hodgkin's disease and other B-cell malignancies. Combination of rituximab with cytotoxic agents or cytokines has been explored in a number of different studies. Rituximab is now also approved for patients with diffuse large B-cell lymphoma when combined with standard CHOP chemotherapy (cyclophosphamide, doxorubicin, vincristine and prednisone). The monoclonal antibody is generally well tolerated. Most adverse events are infusion-associated, including chills, fever and rigor related to the release of cytokines.

[Hodgkin's lymphoma in nuclear medicine: diagnostic and therapeutic aspects]

Today, diagnostic and therapeutic strategies of Hodgkin lymphoma (HL) with positron emission tomography and radioimmunotherapy include state-of-the-art nuclear medicine which require the cooperation between oncology and nuclear medicine. The benefit of FDG-PET in HL patients with residual tumor masses consists of its high negative predictive value in the therapy control of the disease. The concept of waitful watching in patients with PET-negative residual masses after BEACOPP-chemotherapy will be evaluated in a large multicenter trial of the GHSG (German Hodgkin Study Group). Radioimmunotherapy has been performed in patients with CD20-positive Non-Hodgkin lymphoma for 10 years with promising results. HL is also an excellent target for immunotherapy due to the expression of antigens such as CD25 and CD30. Thus, a new radioimmunoconstruct consisting of the murine anti-CD30 antibody Ki-4 labeled with iodine-131 was developed for patients with relapsed or refractory HL.

Granulocyte transfusion therapy for treatment of infections after cytotoxic chemotherapy

Opportunistic fungal infections and antibiotic-refractory bacterial infections remain important causes of morbidity and mortality in neutropenic individuals. Furthermore, the expanding use of dose-intensive cancer treatment strategies has increased the frequency of prolonged neutropenia. Therefore, the transfusion of granulocytes should be a logical therapeutic approach. Substantial progress has been made in the field of granulocyte transfusion therapy during the past decade. Interest in granulocyte transfusion therapy has been rekindled by both the use of hematopoietic growth factors to mobilize neutrophils and modern leukapheresis techniques. Moreover, promising results were observed in the use of community donors and in granulocyte storage experiments, which could enhance the ability of blood banks for institution of granulocyte concentrates. Recent clinical trials suggest that granulocyte transfusion therapy may be effective and well-tolerated in the neutropenic patient affected by life-threatening infections. These results must be confirmed in controlled, clinical trials.

Hodgkin’s lymphoma in nuclear medicine: diagnostic and therapeutic aspects

Today, diagnostic and therapeutic strategies of Hodgkin lymphoma (HL) with positrone emission tomography and radioiummunotherapy include state-of-the-art nuclear medicine which require the cooperation between oncology and nuclear medicine. The benefit of FDG-PET in HL patients with residual tumor masses consists of its high negative predictive value in the therapy control of the disease. The concept of waitful watching in patients with PET-negative residual masses after BEACOPPchemotherapy will be evaluated in a large multicenter trial of the GHSG (German Hodgkin Study Group). Radioimmunotherapy has been performed in patients with CD20-positive Non-Hodgkin lymphoma for 10 years with promising results. HL is also an excellent target for immunotherapy due to the expression of antigens such as CD25 and CD30. Thus, a new radio-immunoconstruct consisting of the murine anti-CD30 antibody Ki-4 labeled with iodine-131 was developed for patients with relapsed or refractory HL.

Current strategies of antibody-based treatment in Hodgkin's disease

Many new approaches involving antibody-based agents have given promising results in experimental Hodgkin's disease (HD) models. Clinical trials with monoclonal antibodies, immunotoxins, bispecific constructs and radioimmunoconjugates have demonstrated some clinical efficacy in patients with advanced refractory HD. Although it seems unlikely that resistant patients with larger tumor masses will be cured by either of these approaches, it might be feasible to treat bulky disease by conventional therapy and then administer biological agents to kill residual Hodgkin and Reed-Sternberg cells. Future phase III trials will have to prove a possible superior effect of this combined immunochemotherapy. Currently, the evaluation of the most promising approaches continues.

Time-intensified dexamethasone/cisplatin/cytarabine: an effective salvage therapy with low toxicity in patients with relapsed and refractory Hodgkin's disease

BACKGROUND

An important variable affecting outcome in relapsed and refractory Hodgkin's disease (HD) is the potential of conventional salvage chemotherapy to reduce tumor volume before high-dose chemotherapy (HDCT) and autologous stem cell transplantation. Currently, the optimal salvage chemotherapy regimen for these patients is unclear. Since dexamethasone/cisplatin/cytarabine (DHAP) given at 3-4 week intervals has been shown to be very effective in patients with relapsed aggressive non-Hodgkin's lymphoma, we evaluated this regimen given at a median of 16-day intervals in patients with relapsed and refractory HD.

PATIENTS AND METHODS

Patients with relapsed or refractory HD were treated with two cycles of DHAP [dexamethasone 40 mg intravenously (i.v.) day 1-4, cisplatin 100 mg/m(2) i.v. as 24-h continuous infusion day 1, and cytarabine 2 g/m(2) i.v. 12q day 2]. Granulocyte colony-stimulating factor (G-CSF) was given at a dose of 5 micro g/kg from day 4 until day 13. Patients with partial remission (PR) or complete remission (CR) after two cycles of DHAP received sequential HDCT.

RESULTS

The median age of the 102 patients included was 34 years (range 21-64 years). Forty-two percent of the patients had late relapse, 29% early relapse, 12% multiple relapse and 16% primary progressive/refractory disease. The response rate (RR) after two cycles of DHAP was 89% (21% CR, 68% PR). The RRs for patients with late, early, multiple and progressive HD were 91%, 93%, 92% and 65%, respectively. Using the chi-square test for independence, remission status (relapsed HD versus progressive HD) and stage at relapse (stage I/II versus stage III/IV) were significant factors for response to DHAP. WHO grade 4 leukocytopenia and thrombocytopenia were the main toxic- ities occurring in 43% (mean duration 1.1 days, range 0-6) and 48% (mean duration 1.4 days, range 0-11) of all courses, respectively. Neither severe infections nor treatment-related deaths occurred. Peripheral blood stem cells (PBSCs) were collected after the first cycle DHAP in eight patients. The hematopoietic progenitors showed a very rapid increase from day 10 with a synchronous and impressive peak on day 12. A mean of 6.1 x 10(6)/kg CD34(+) cells were collected per apheresis. As originally recommended in the protocol, PBSCs were routinely collected during sequential HDCT in the remaining patients.

CONCLUSIONS

A brief tumor-reducing program with two cycles of DHAP given in short intervals supported by G-CSF is effective and well-tolerated in patients with relapsed and refractory HD. This regimen can be used to mobilize stem cells and select those patients with chemosensitive relapse who should subsequently be treated with HDCT.