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1.
BMC Cancer ; 16: 282, 2016 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-27098429

RESUMO

BACKGROUND: Primary central nervous system lymphoma (PCNSL) is a highly aggressive Non-Hodgkin lymphoma (NHL) with rising incidence over the past 30 years in immunocompetent patients. Although outcomes have improved, PCNSL is still associated with inferior prognosis compared to systemic NHL. Many questions regarding the optimal therapeutic approach remain unanswered. METHODS/DESIGN: This is a randomized, open-label, international phase III trial with two parallel arms. We will recruit 250 patients with newly diagnosed PCNSL from approximately 35 centers within the networks of the German Cooperative PCNSL study group and the International Extranodal Lymphoma Study Group. All enrolled patients will undergo induction chemotherapy consisting of 4 cycles of rituximab 375 mg/m(2)/d (days 0 & 5), methotrexate 3.5 g/m(2) (d1), cytarabine 2 × 2 g/m(2)/d (d2-3), and thiotepa 30 mg/m(2) (d4) every 21 days. All patients will undergo stem-cell harvest after the second cycle. After 4 cycles of induction chemotherapy, patients achieving partial or complete response will be centrally randomized to 2 different consolidation treatments: (A) conventional-dose immuno chemotherapy with rituximab 375 mg/m(2) (d0), dexamethasone 40 mg/d (d1-3), etoposide 100 mg/m(2)/d (d1-3), ifosfamide 1500 mg/m(2)/d (d1-3) and carboplatin 300 mg/m(2) (d1) (R-DeVIC) or (B) high-dose chemotherapy with BCNU (or busulfan) and thiotepa followed by autologous stem cell transplantation (HCT-ASCT). The objective is to demonstrate superiority of HCT-ASCT compared to R-DeVIC with respect to progression-free survival (PFS, primary endpoint). Secondary endpoints include overall survival (OS), treatment response and treatment-related morbidities. Minimal follow-up after treatment completion is 24 months. DISCUSSION: The rationale for consolidation treatment in PCNSL is to eliminate residual lymphoma cells and to decrease the risk for relapse. This can be achieved by agents crossing the blood brain barrier either applied at conventional doses or at high doses requiring autologous stem cell support. HCT-ASCT has been shown to be feasible and highly effective in patients with newly-diagnosed PCNSL. However, it is unclear whether HCT-ASCT is really superior compared to conventional-dose chemotherapy after an intensified antimetabolites-based immunochemotherapy in patients with newly-diagnosed PCNSL. To answer this question, we designed this investigator initiated randomized phase III trial. TRIAL REGISTRATION: German clinical trials registry DRKS00005503 registered 22 April 2014 and ClinicalTrials.gov NCT02531841 registered 24 August 2015.


Assuntos
Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Linfoma não Hodgkin/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Transplante de Células-Tronco , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias do Sistema Nervoso Central/patologia , Terapia Combinada , Citarabina/administração & dosagem , Intervalo Livre de Doença , Etoposídeo/administração & dosagem , Feminino , Humanos , Ifosfamida/administração & dosagem , Linfoma não Hodgkin/patologia , Masculino , Metotrexato/administração & dosagem , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Tiotepa/administração & dosagem , Transplante Autólogo
4.
Blood ; 117(5): 1483-91, 2011 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-21045197

RESUMO

Idiotype vaccination for follicular lymphoma is primarily being developed as remission consolidation after chemotherapy. We investigated idiotype vaccination as primary intervention for treatment-naive indolent B-cell lymphoma and in a separate cohort as remission consolidation after chemotherapy to assess immunization-induced immune responses in relation to progression-free survival (German Clinical Trials Register, DRKS00000227). Twenty-one patients in each cohort received 6 intradermal injections of adjuvanted recombinant idiotype Fab fragment (Fab(Id)); 76% of patients in both groups developed anti-idiotype antibodies and/or cellular immunity as measured by enzyme-linked immunosorbent assay and interferon-γ ELISpot. In treatment-naive patients, only cellular responses correlated with superior progression-free survival (P < .002) and durable objective remissions (P = .04). Immunization-induced T cells recognized hypermutated or complementarity-determining region 3 epitopes. After remission consolidation immunization, induction of anti-idiotype antibodies correlated with progression-free survival. Low B-cell counts after rituximab therapy predicted for failure to develop anti-idiotype antibodies. These results are similar to published trials showing an association of humoral immunity with control of residual lymphoma. In contrast, effective immunity against untreated lymphoma appears to be dependent on idiotype-specific T cells. Sustained remissions in patients with vaccination-induced cellular immunity suggest clinical benefit and warrant a randomized comparison of this vaccine with expectant management for asymptomatic follicular lymphoma.


Assuntos
Vacinas Anticâncer/uso terapêutico , Fragmentos Fab das Imunoglobulinas/imunologia , Idiótipos de Imunoglobulinas/imunologia , Linfoma de Células B/imunologia , Linfoma de Células B/terapia , Proteínas Recombinantes/imunologia , Adulto , Idoso , Linfócitos B/imunologia , Epitopos de Linfócito T/imunologia , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Indução de Remissão , Taxa de Sobrevida , Resultado do Tratamento , Vacinação
5.
Blood ; 116(10): 1734-6, 2010 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-20522710

RESUMO

Active immunization with the idiotype of follicular lymphoma induces tumor-specific immunity. T cells induced in vivo by idiotype vaccination recognize human leukocyte antigen (HLA)--restricted hypervariable but not conserved idiotype peptides. We hypothesized that idiotype-directed T-cell immunity occurs naturally and performed a reverse immunology analysis of idiotype HLA binding in 39 follicular lymphoma patients. For every idiotype, the sum of HLA-A or -B binding scores of the 20 highest-scoring peptides was calculated for all 39 HLA types through the BIMAS algorithm. The idiotype sum score of every patient's lymphoma was compared on the respective patient's HLA type to the mean of the sum scores of the remaining 38 idiotypes. Autologous idiotypes had lower immunogenicity than allogeneic idiotypes. Differential immunogenicity resided predominantly in all 3 complementarity-determining regions rather than in framework peptides. Idiotype immunogenicity was not changed by somatic hypermutation. These findings indicate T cell-mediated immunosurveillance of follicular lymphoma directed specifically against individual idiotype epitopes.


Assuntos
Antígenos HLA/imunologia , Idiótipos de Imunoglobulinas/imunologia , Linfoma Folicular/imunologia , Linfócitos T/imunologia , Adulto , Idoso , Algoritmos , Alelos , Epitopos de Linfócito T/genética , Epitopos de Linfócito T/imunologia , Epitopos de Linfócito T/metabolismo , Feminino , Antígenos HLA/genética , Antígenos HLA/metabolismo , Antígenos HLA-A/genética , Antígenos HLA-A/imunologia , Antígenos HLA-A/metabolismo , Antígenos HLA-B/genética , Antígenos HLA-B/imunologia , Antígenos HLA-B/metabolismo , Humanos , Idiótipos de Imunoglobulinas/genética , Idiótipos de Imunoglobulinas/metabolismo , Linfoma Folicular/genética , Linfoma Folicular/metabolismo , Masculino , Pessoa de Meia-Idade , Monitorização Imunológica/estatística & dados numéricos , Ligação Proteica , Linfócitos T/citologia , Linfócitos T/metabolismo
6.
Eur J Haematol ; 77(5): 395-402, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16879605

RESUMO

OBJECTIVES: Individual immunoglobulins expressed by B-cell lymphomas represent tumor-specific antigens ('idiotypes'). Immunization with idiotype in follicular lymphoma patients may induce specific immune responses, sustained progression-free survival, and disappearance of minimal residual disease. Manufacturing of idiotype vaccines has mostly relied on heterohybridomas established from viable lymphoma cells. This paper describes the feasibility of production of GMP-grade idiotype vaccines as recombinant Fab fragments in Escherichia coli. METHODS: IgH and IgL transcripts were analyzed by anchored PCR from 106 lymphoma and nine control biopsies. Lymphoma-derived V segments were inserted into prokaryotic expression plasmids. Recombinant idiotype Fab fragments were expressed in E. coli in a fermentation system. RESULTS: Idiotype IgH and IgL transcripts were identified in 95% of 106 lymphoma biopsies according to stringent clonality criteria. Large-scale idiotype expression was successful in 69 of 78 cases (89%) and yielded a median of 17 mg (range: 1.2-250 mg) recombinant Fab protein. After affinity chromatography, median vaccine purity was 99% heterodimeric Fab protein (range: 72-100%). Bacterial protein contamination was detectable in one vaccine only. Fab proteins with IgL lambda chains had a tendency for inferior yield and lesser purity than kappa-type Fabs. Among other structural idiotype features (isotype, V family usage, somatic hypermutation pattern, novel glycosylation sites, CDR III net charge), no consistent influences on Fab yield or purity were detected. CONCLUSIONS: Anchored PCR cloning and subsequent protein expression in E. coli provides a reliable technological basis for clinical idiotype vaccination trials.


Assuntos
Vacinas Anticâncer/genética , Fragmentos Fab das Imunoglobulinas/genética , Cadeias Pesadas de Imunoglobulinas/genética , Idiótipos de Imunoglobulinas/genética , Cadeias Leves de Imunoglobulina/genética , Linfoma de Células B/genética , Linfoma Folicular/genética , Vacinas Anticâncer/isolamento & purificação , Vacinas Anticâncer/uso terapêutico , Escherichia coli/genética , Humanos , Fragmentos Fab das Imunoglobulinas/isolamento & purificação , Fragmentos Fab das Imunoglobulinas/uso terapêutico , Cadeias Pesadas de Imunoglobulinas/isolamento & purificação , Cadeias Pesadas de Imunoglobulinas/uso terapêutico , Idiótipos de Imunoglobulinas/isolamento & purificação , Idiótipos de Imunoglobulinas/uso terapêutico , Cadeias Leves de Imunoglobulina/isolamento & purificação , Cadeias Leves de Imunoglobulina/uso terapêutico , Linfoma de Células B/terapia , Linfoma Folicular/terapia , Reação em Cadeia da Polimerase/métodos , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/uso terapêutico , Vacinação
7.
Cancer Res ; 66(8): 4496-502, 2006 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-16618777

RESUMO

The immunoglobulin receptor of B-cell lymphomas constitutes a specific tumor antigen (idiotype) and a target for active immunotherapy. Encouraging results have been reported in phase II trials after s.c. vaccination of follicular lymphoma patients during clinical remission with idiotype produced from eukaryotic cell lines and coupled to an immunogenic carrier macromolecule. We have developed a good manufacturing protocol for rapid expression of idiotype vaccines as recombinant Fab fragments in Escherichia coli. The objectives of this trial were to show safety and feasibility of intradermal immunization with this vaccine and to investigate whether immune responses were induced by this immunization route. Patients (n = 18) with advanced B-cell malignancies received repetitive intradermal vaccinations with 0.5 to 1.65 mg recombinant idiotype Fab fragment mixed with lipid-based adjuvant in combination with 150 mug granulocyte macrophage colony-stimulating factor s.c. at the same location. The patients' immune status was assessed by flow cytometry of peripheral blood lymphocytes and concomitant hepatitis B vaccination. Cellular and humoral immune responses to the vaccine were assessed by enzyme-linked immunospot and ELISA. Side effects of a total of 65 vaccinations were mild and did not affect the immunization schedule. No patient developed hepatitis B surface antibodies (anti-HBs) after two hepatitis B immunizations. Of 17 evaluable patients, five developed specific anti-vaccine antibodies, and eight developed anti-Fab T-cell responses. T-cell reactivity was independent of the cellular immune status and was idiotype specific as shown by statistical regression analysis (P = 0.0024) and epitope mapping studies. Intradermal administration of uncoupled recombinant idiotype with appropriate adjuvants may overcome profound clinical immunosuppression and induce specific immune responses.


Assuntos
Vacinas Anticâncer/uso terapêutico , Linfoma de Células B/imunologia , Linfoma de Células B/terapia , Vacinação/métodos , Adulto , Idoso , Sequência de Aminoácidos , Linfócitos B/imunologia , Vacinas Anticâncer/efeitos adversos , Vacinas Anticâncer/imunologia , Epitopos de Linfócito T , Feminino , Humanos , Idiótipos de Imunoglobulinas/imunologia , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Linfócitos T/imunologia , Resultado do Tratamento
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