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Featured researches published by Tomas Kozak.


Journal of Clinical Oncology | 2010

Ofatumumab As Single-Agent CD20 Immunotherapy in Fludarabine-Refractory Chronic Lymphocytic Leukemia

William G. Wierda; Thomas J. Kipps; Jiří Mayer; Stephan Stilgenbauer; Cathy Williams; Andrzej Hellmann; Tadeusz Robak; Richard R. Furman; Peter Hillmen; Marek Trneny; Martin J. S. Dyer; Swami Padmanabhan; Magdalena Piotrowska; Tomas Kozak; Geoffrey Chan; Randy Davis; Nedjad Losic; Joris Wilms; Charlotte A. Russell; Anders Österborg

PURPOSE New treatments are needed for patients with fludarabine- and alemtuzumab-refractory (FA-ref) chronic lymphocytic leukemia (CLL) or patients with fludarabine-refractory CLL with bulky (> 5 cm) lymphadenopathy (BF-ref) who are less suitable for alemtuzumab treatment; these groups have poor outcomes with available salvage regimens. Ofatumumab (HuMax-CD20) is a human monoclonal antibody targeting a distinct small-loop epitope on the CD20 molecule. We conducted an international clinical study to evaluate the efficacy and safety of ofatumumab in patients with FA-ref and BF-ref CLL. PATIENTS AND METHODS Patients received eight weekly infusions of ofatumumab followed by four monthly infusions during a 24-week period (dose 1 = 300 mg; doses 2 to 12 = 2,000 mg); response by an independent review committee (1996 National Cancer Institute Working Group criteria) was assessed every 4 weeks until week 24 and then every 3 months until month 24. RESULTS This planned interim analysis included 138 treated patients with FA-ref (n = 59) and BF-ref (n = 79) CLL. The overall response rates (primary end point) were 58% [corrected] and 47% in the FA-ref and BF-ref groups, respectively. Complete resolution of constitutional symptoms and improved performance status occurred in 57% and 48% of patients, respectively. Median progression-free survival and overall survival times were 5.7 and 13.7 months in the FA-ref group, respectively, and 5.9 and 15.4 months in the BF-ref group, respectively. The most common adverse events during treatment were infusion reactions and infections, which were primarily grade 1 or 2 events. Hematologic events during treatment included anemia and neutropenia. CONCLUSION Ofatumumab is an active, well-tolerated treatment providing clear clinical improvements for fludarabine-refractory patients with very poor-prognosis CLL.


Haematologica | 2010

Autologous hematopoietic stem cell transplantation for autoimmune diseases: an observational study on 12 years’ experience from the European Group for Blood and Marrow Transplantation Working Party on Autoimmune Diseases

Dominique Farge; Myriam Labopin; Alan Tyndall; A Fassas; Gian Luigi Mancardi; Jaap Van Laar; Jian Ouyang; Tomas Kozak; John Moore; Ina Kötter; Virginie Chesnel; Alberto M. Marmont; Alois Gratwohl; Riccardo Saccardi

Background Autologous hematopoietic stem cell transplantation has been used since 1996 for the treatment of severe autoimmune diseases refractory to approved therapies. We evaluated the long-term outcomes of these transplants and aimed to identify potential prognostic factors. Design and Methods In this observational study we analyzed all first autologous hematopoietic stem cell transplants for autoimmune diseases reported to the European Group for Blood and Marrow Transplantation (EBMT) registry between 1996–2007. The primary end-points for analysis were overall survival, progression-free survival and transplant-related mortality at 100 days. Results Nine hundred patients with autoimmune diseases (64% female; median age, 35 years) who underwent a first autologous hematopoietic stem cell transplant were included. The main diseases were multiple sclerosis (n=345), systemic sclerosis (n=175), systemic lupus erythematosus (n=85), rheumatoid arthritis (n=89), juvenile arthritis (n=65), and hematologic immune cytopenia (n=37). Among all patients, the 5-year survival was 85% and the progression-free survival 43%, although the rates varied widely according to the type of autoimmune disease. By multivariate analysis, the 100-day transplant-related mortality was associated with the transplant centers’ experience (P=0.003) and type of autoimmune disease (P=0.03). No significant influence of transplant technique was identified. Age less than 35 years (P=0.004), transplantation after 2000 (P=0.0015) and diagnosis (P=0.0007) were associated with progression-free survival. Conclusions This largest cohort studied worldwide shows that autologous hematopoietic stem cell transplantation can induce sustained remissions for more than 5 years in patients with severe autoimmune diseases refractory to conventional therapy. The type of autoimmune disease, rather than transplant technique, was the most relevant determinant of outcome. Results improved with time and were associated with the transplant centers’ experience. These data support ongoing and planned phase III trials to evaluate the place of autologous hematopoietic stem cell transplantation in the treatment strategy for severe autoimmune diseases.


Journal of Neurology | 2002

Hematopoietic stem cell transplantation for multiple sclerosis

A Fassas; Jakob Passweg; Achilles Anagnostopoulos; A. Kazis; Tomas Kozak; Eva Havrdova; Enric Carreras; Francesc Graus; Ashwin Kashyap; Harry Openshaw; M. Schipperus; Eric Deconinck; Giovanni Luigi Mancardi; Alberto M. Marmont; J. Hansz; Marco Rabusin; F. J. Zuazu Nagore; J. Besalduch; T. Dentamaro; Loic Fouillard; Bernd Hertenstein; G. La Nasa; Maurizio Musso; Federico Papineschi; J. M. Rowe; Riccardo Saccardi; Andreas J. Steck; Ludwig Kappos; Alois Gratwohl; Alan Tyndall

Rationale Phase I/II studies of autologous hematopoietic stem cell transplantation (HSCT) for multiple sclerosis (MS) were initiated, based on results of experimental transplantation in animal models of multiple sclerosis and clinical observations in patients treated concomitantly for malignant disease. Patients Eighty-five patients with progressive MS were treated with autologous HSCT in 20 centers and reported to the autoimmune disease working party of the European Group for Blood and Marrow Transplantation (EBMT). 52 (61 %) were female, median age was 39 [20-58] years. The median interval from diagnosis to transplant was 7 [1-26] years. Patients suffered from severe disease with a median EDSS score of 6.5 [4.5-8.5]. Active disease prior to transplant was documented in 79 of 82 evaluable cases. Results The stem cell source was bone marrow in 6 and peripheral blood in 79, and stem cells were mobilized into peripheral blood using either cyclophosphamide combined with growth factors or growth factors alone. Three patients experienced transient neurological complications during the mobilization phase. The high dose regimen included combination chemotherapy, with or without anti-lymphocyte antibodies or, with or without, total body irradiation. The stem cell transplants were purged of lymphocytes in 52 patients. Median follow-up was 16 [3-59] months. There were 7 deaths, 5 due to toxicity and infectious complications, 2 with neurological deterioration. The risk of death of any cause at 3 years was 10 (±7)% (95 % confidence interval). Neurological deterioration during transplant was observed in 22 patients; this was transient in most but was associated with MS progression in 6 patients. Neurological improvement by ≥ 1 point in the EDSS score was seen in 18 (21 %) patients. Confirmed progression-free survival was 74 (±12)% at 3 years being 66 (±23)% in patients with primary progressive MS but higher in patients with secondary progressive or relapsing-remitting MS, 78 (±13)%; p = 0.59. The probability of confirmed disease progression was 20 (±11)%. MRI data were available in 78 patients before transplant showing disease activity (gadolinium enhancing, new or enlarging lesions) in 33 %. Posttransplant MRI showed activity at any time in 5/61 (8 %) evaluable cases. Conclusion Autologous HSCT suggest positive early results in the management of progressive MS and is feasible. These multicentre data suggest an association with significant mortality risks especially in some patient groups and are being utilised in the planning of future trials to reduce transplant related mortality.


Bone Marrow Transplantation | 2005

Autologous hematopoietic stem cell transplantation for autoimmune diseases

Alois Gratwohl; Jakob Passweg; Chiara Bocelli-Tyndall; A Fassas; J M van Laar; D Farge; M. Andolina; Rudolf Arnold; Enric Carreras; J Finke; Ina Kötter; Tomas Kozak; Igor Lisukov; B. Lowenberg; Alberto M. Marmont; John Moore; Riccardo Saccardi; John A. Snowden; F.H.J. van den Hoogen; N Wulffraat; X. Zhao; Alan Tyndall

Summary:Experimental data and early phase I/II studies suggest that high-dose chemotherapy followed by autologous hematopoietic stem cell transplantation (HSCT) can arrest progression of severe autoimmune diseases. We have evaluated the toxicity and disease response in 473 patients with severe autoimmune disease treated with autologous HSCT between 1995 and 2003, from 110 centers participating in the European Group for Blood and Marrow Transplantation (EBMT) autoimmune disease working party database. Survival, transplant-related mortality, treatment response and disease progression were assessed. In all, 420 patients (89%; 86±4% at 3 years, median follow-up 20 months) were alive, 53 (11%) had died from transplant-related mortality (N=31; 7±3% at 3 years) or disease progression (N=22; 9±4% at 3 years). Of 370 patients, 299 evaluable for response (81%) showed a treatment response, which was sustained in 213 (71% of responders). Response was associated with disease (P<0.001), was better in patients who received cyclophosphamide during mobilization (relative risk (RR)3.28 (1.57–6.83)) and was worse with increasing age (>40 years, RR0.29 (0.11–0.82)). Disease progression was associated with disease (P<0.001) and conditioning intensity (high intensity, RR1; intermediate intensity, RR1.81 (0.96–3.42)); low intensity, RR2.34 (1.074–5.11)). These data from the collective EBMT experience support the hypothesis that autologous HSCT can alter disease progression in severe autoimmune disease.


Multiple Sclerosis Journal | 2006

Autologous stem cell transplantation for progressive multiple sclerosis : Update of the European Group for Blood and Marrow Transplantation autoimmune diseases working party database

Riccardo Saccardi; Tomas Kozak; C Bocelli-Tyndall; A Fassas; A. Kazis; Eva Havrdova; Enric Carreras; Albert Saiz; Bob Löwenberg; P Aw te Boekhorst; F. Gualandi; Harry Openshaw; G Longo; Francesca Pagliai; Luca Massacesi; E Deconink; Jian Ouyang; F Jz Nagore; Juan Besalduch; I A Lisukov; A Bonini; Elisa Merelli; Shimon Slavin; Alois Gratwohl; J Passweg; Alan Tyndall; Andreas J. Steck; M Andolina; M Capobianco; J Ld Martin

Over the last decade, hematopoietic stem cells transplantation (HSCT) has been increasingly used in the treatment of severe progressive autoimmune diseases. We report a retrospective survey of 183 multiple sclerosis (MS) patients, recorded in the database of the European Blood and Marrow Transplantation Group (EBMT). Transplant data were available from 178 patients who received an autologous graft. Overall, transplant related mortality (TRM) was 5.3% and was restricted to the period 1995-2000, with no further TRM reported since then. Busulphan-based regimens were significantly associated with TRM. Clinical status at the time of transplant and transplant techniques showed some correlations with toxicity. No toxic deaths were reported among the 53 patients treated with the BEAM (carmustine, etoposide, cytosine-arabinoside, melphalan)/antithymocyte globulin (ATG) regimen without graft manipulation, irrespective of their clinical condition at the time of the transplant. Improvement or stabilization of neurological conditions occurred in 63% of patients at a median follow-up of 41.7 months, and was not associated with the intensity of the conditioning regimen. In this large series, HSCT was shown as a promising procedure to slow down progression in a subset of patients affected by severe, progressive MS; the safety and feasibility of the procedure can be significantly improved by appropriate patient selection and choice of transplant regimen.


Bone Marrow Transplantation | 2001

Collection of hematopoietic stem cells from patients with autoimmune diseases

Richard K. Burt; A Fassas; John A. Snowden; J M van Laar; Tomas Kozak; Nico Wulffraat; Richard A. Nash; Cynthia E. Dunbar; Rudolf Arnold; G Prentice; Sarah J. Bingham; Alberto M. Marmont; Peter A. McSweeney

We reviewed data from 24 transplant centers in Asia, Australia, Europe, and North America to determine the outcomes of stem cell collection including methods used, cell yields, effects on disease activity, and complications in patients with autoimmune diseases. Twenty-one unprimed bone marrow harvests and 174 peripheral blood stem cell mobilizations were performed on 187 patients. Disease indications were multiple sclerosis (76 patients), rheumatoid arthritis (37 patients), scleroderma (26 patients), systemic lupus erythematosus (19 patients), juvenile chronic arthritis (13 patients), idiopathic autoimmune thrombocytopenia (8 patients), Behcets disease (3 patients), undifferentiated vasculitis (3 patients), polychondritis (1 patient) and polymyositis (1 patient). Bone marrow harvests were used in the Peoples Republic of China and preferred worldwide for children. PBSC mobilization was the preferred technique for adult stem cell collection in America, Australia, and Europe. Methods of PBSC mobilization included G-CSF (5, 10, or 16 μg/kg/day) or cyclophosphamide (2 or 4 g/m2) with either G-CSF (5 or 10 μg/kg/day) or GM-CSF (5 μg/kg/day). Bone marrow harvests were without complications and did not affect disease activity. A combination of cyclophosphamide and G-CSF was more likely to ameliorate disease activity than G-CSF alone (P < 0.001). G-CSF alone was more likely to cause disease exacerbation than the combination of cyclophosphamide and G-CSF (P = 0.003). Three patients died as a result of cyclophosphamide-based stem cell collection (2.6% of patients mobilized with cyclophosphamide). When corrected for patient weight and apheresis volume, progenitor cell yields tended to vary by underlying disease, prior medication history and mobilization regimen. Trends in the approaches to, and results of, progenitor cell mobilization are suggested by this survey. While cytokine-based mobilization appears less toxic, it is more likely to result in disease reactivation. Optimization with regard to cell yields and safety are likely to be disease-specific and prospective disease-specific studies of mobilization procedures appear warranted. Bone Marrow Transplantation (2001) 28, 1–12.


Bone Marrow Transplantation | 2000

High-dose immunosuppressive therapy with PBPC support in the treatment of poor risk multiple sclerosis.

Tomas Kozak; Eva Havrdova; Pitha J; Gregora E; Robert Pytlik; Maaloufová J; Helena Mareckova; Petr Kobylka; Vodvárková S

High-dose immunoablative chemotherapy with autologous haematopoietic cell support might be beneficial in the treatment of intractable forms of MS. We mobilised PBPC in 11 patients with secondary progressive MS and finally eight patients were grafted after high-dose BEAM chemotherapy with either in vitro or in vivo T cell depletion. Median EDSS and SNRS scores at the time of inclusion were 6.5 (6.5–7.5) and 56 (44–65), respectively. PBPC mobilisation was safe with no serious adverse effects, and without significant aggravation of disability. One patient improved significantly (by 1.0 point on EDSS) after the mobilisation. Two mobilisation failures were observed. No life-threatening events occurred during the transplantation. All grafted patients, except one, at least stabilised their disability status. One patient improved significantly (by 1.5 points on EDSS), two patients improved slightly (by 0.5 points on EDSS), one patient worsened by 1.0 point on the EDSS in 10 months. Improvement occurred with a delay of 2–4 months. Median EDSS and SNRS of grafted patients at the last follow up were 6.5 (5.5–8.5) and 64 (39–73), respectively with median follow-up of 8.5 months. Further follow-up is needed to determine the disease course after complete immune reconstitution. Bone Marrow Transplantation (2000) 25, 525–531.


Cancer | 2009

Vincristine sulfate liposomes injection (Marqibo) in heavily pretreated patients with refractory aggressive non-Hodgkin lymphoma: Report of the pivotal phase 2 study

Maria Alma Rodriguez; Robert Pytlik; Tomas Kozak; Mukesh Chhanabhai; Randy D. Gascoyne; Biao Lu; Steven R. Deitcher; Jane N. Winter

Marqibo, a sphingosomal/cholesterol encapsulation of vincristine sulfate has targeted, increased, and sustained delivery of vincristine to tumor tissues. A phase 2, open‐label, single‐arm, and multinational study evaluated the efficacy and tolerability of Marqibo as a single agent in patients with multiply relapsed or refractory aggressive non‐Hodgkin lymphoma (NHL).


Journal of Clinical Oncology | 2013

Rituximab Purging and/or Maintenance in Patients Undergoing Autologous Transplantation for Relapsed Follicular Lymphoma: A Prospective Randomized Trial From the Lymphoma Working Party of the European Group for Blood and Marrow Transplantation

Ruth Pettengell; Norbert Schmitz; Christian Gisselbrecht; Graeme C. Smith; William Nigel Patton; Bernd Metzner; Dolores Caballero; Hervé Tilly; Jan Walewski; Isabelle Bence-Bruckler; Bik To; Christian H. Geisler; Rik Schots; Eva Kimby; Christian Taverna; Tomas Kozak; Peter Dreger; Ruzena Uddin; Carmen Ruiz de Elvira; Anthony H. Goldstone

PURPOSE The objective of this randomized trial was to assess the efficacy and safety of rituximab as in vivo purging before transplantation and as maintenance treatment immediately after high-dose chemotherapy and autologous stem-cell transplantation (HDC-ASCT) in patients with relapsed follicular lymphoma (FL). PATIENTS AND METHODS Patients with relapsed FL who achieved either complete or very good partial remission with salvage chemotherapy were randomly assigned using a factorial design to rituximab purging (P+; 375 mg/m(2) once per week for 4 weeks) or observation (NP) before HDC-ASCT and to maintenance rituximab (M+; 375 mg/m(2) once every 2 months for four infusions) or observation (NM). RESULTS From October 1999 to April 2006, 280 patients were enrolled. The median age was 51 years (range, 26 to 70 years), and baseline characteristics were well balanced between groups. On average, patients were 44 months (range, 3 to 464 months) from diagnosis, with 79% having received two lines and 15% three lines of prior therapy. Median follow-up was 8.3 years. In contrast to purging, 10-year progression-free survival (PFS) was 48% for P+ and 42% for NP groups (hazard ratio [HR], 0.80; 95% CI, 0.58 to 1.11; P = .18); maintenance had a significant effect on PFS (10-year PFS, 54% for M+ and 37% for NM; HR, 0.66; 95% CI, 0.47 to 0.91; P = .012). Overall survival (OS) was not improved by either rituximab purging or maintenance. CONCLUSION Rituximab maintenance after HDC-ASCT is safe and significantly prolongs PFS but not OS in patients undergoing transplantation for relapsed FL. Pretransplantation rituximab in vivo purging, even in rituximab-naive patients, failed to improve PFS or OS.


Circulation | 2005

Early Tissue Distribution of Bone Marrow Mononuclear Cells After Transcoronary Transplantation in a Patient With Acute Myocardial Infarction

Martin Penicka; Petr Widimsky; Petr Kobylka; Tomas Kozak; Otto Lang

A 57-year-old man with no history of coronary artery disease was admitted for acute anterior ST-segment–elevation myocardial infarction caused by an occlusion of the proximal left anterior descending (LAD) coronary artery. The culprit artery was recanalized with direct stenting with an optimal result. Left ventricular ejection fraction was 40% with anteroapicoseptal akinesia. A positron-emission tomography study demonstrated reduced perfusion and borderline fluorine-18-fluorodeoxyglucose uptake in apical segments and adjacent anterior and septal wall, suggesting reduced viability in the distal LAD territory. Nine days after infarction, the patient underwent autologous bone marrow stem cell transplantation as a part of a research protocol. Bone marrow blood was aspirated under local anesthesia from both iliac crests. A total of 27.4×108 of …

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Jana Markova

Charles University in Prague

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David Belada

Charles University in Prague

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Robert Pytlik

Charles University in Prague

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Heidi Mocikova

Charles University in Prague

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Marek Trneny

Charles University in Prague

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Vladimír Koza

Charles University in Prague

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Lukas Smolej

Charles University in Prague

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Martin Spacek

Charles University in Prague

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