Mels Hoogendoorn

Platelet doubling after the first azacitidine cycle is a promising predictor for response in myelodysplastic syndromes (MDS), chronic myelomonocytic leukaemia (CMML) and acute myeloid leukaemia (AML) patients in the Dutch azacitidine compassionate named patient programme.

The efficacy of azacitidine in the treatment of high‐risk myelodysplastic syndromes (MDS), chronic myelomonocytic leukaemia (CMML) and acute myeloid leukaemia (AML) (20–30% blasts) has been demonstrated. To investigate the efficacy of azacitidine in daily clinical practice and to identify predictors for response, we analysed a cohort of 90 MDS, CMML and AML patients who have been treated in a Dutch compassionate named patient programme. Patients received azacitidine for a median of five cycles (range 1–19). The overall response rate (complete/partial/haematological improvement) was 57% in low risk MDS, 53% in high risk MDS, 50% in CMML, and 39% in AML patients. Median overall survival (OS) was 13·0 (9·8–16·2) months. Multivariate analysis confirmed circulating blasts [Hazard Ratio (HR) 0·48, 95% confidence interval (CI) 0·24–0·99; P = 0·05] and poor risk cytogenetics (HR 0·45, 95% CI 0·22–0·91; P = 0·03) as independent predictors for OS. Interestingly, this analysis also identified platelet doubling after the first cycle of azacitidine as a simple and independent positive predictor for OS (HR 5·4, 95% CI 0·73–39·9; P = 0·10). In conclusion, routine administration of azacitidine to patients with variable risk groups of MDS, CMML and AML is feasible, and subgroups with distinct efficacy of azacitidine treatment can be identified.

Addition of bevacizumab to chemotherapy in acute myeloid leukemia at older age: a randomized phase 2 trial of the Dutch-Belgian Cooperative Trial Group for Hemato-Oncology (HOVON) and the Swiss Group for Clinical Cancer Research (SAKK)

An urgent need for new treatment modalities is emerging in elderly patients with acute myeloid leukemia (AML). We hypothesized that targeting VEGF might furnish an effective treatment modality in this population. Elderly patients with AML were randomly assigned in this phase 2 study (n = 171) to receive standard chemotherapy (3 + 7) with or without bevacizumab at a dose of 10 mg/kg intravenously at days 1 and 15. In the second cycle, patients received cytarabine 1000 mg/m(2) twice daily on days 1-6 with or without bevacizumab. The complete remission rates in the 2 arms were not different (65%). Event-free survival at 12 months was 33% for the standard arm versus 30% for the bevacizumab arm; at 24 months, it was 22% and 16%, respectively (P = .42). The frequencies of severe adverse events (SAEs) were higher in the bevacizumab arm (n = 63) compared with the control arm (n = 28; P = .043), but the percentages of death or life-threatening SAEs were lower in the bevacizumab arm (60% vs 75% of SAEs). The results of the present study show that the addition of bevacizumab to standard chemotherapy does not improve the therapeutic outcome of older AML patients. This trial is registered as number NTR904 in The Nederlands Trial Register (www.trialregister.nl).

Azacitidine results in comparable outcome in newly diagnosed AML patients with more or less than 30% bone marrow blasts

The efficacy of azacitidine has been demonstrated in acute myeloid leukemia (AML) patients with 20-30% bone marrow (BM) blasts, but limited data is available on patients with ≥30% blasts. We analyzed 55 newly diagnosed AML patients, treated with azacitidine. The overall response rate was 42%. Median overall survival (OS) was 12.3 months. We confirmed poor-risk cytogenetics, therapy-related AML, performance score ≥2, and white blood cell count ≥15×10(9)/L as independent adverse predictors for OS. The BM blast percentage, however, had no impact on OS (P=0.55). In conclusion, administration of azacitidine is effective in AML patients with 20-30% and >30% BM blasts.

Generation of B-cell chronic lymphocytic leukemia (B-CLL)-reactive T-cell lines and clones from HLA class I-matched donors using modified B-CLL cells as stimulators: implications for adoptive immunotherapy

Allogeneic stem cell transplantation following reduced-intensity conditioning is being evaluated in patients with advanced B-cell chronic lymphocytic leukemia (B-CLL). The curative potential of this procedure is mediated by donor-derived alloreactive T cells, resulting in a graft-versus-leukemia effect. However, B-CLL may escape T-cell-mediated immune reactivity since these cells lack expression of costimulatory molecules. We examined the most optimal method to transform B-CLL cells into efficient antigen-presenting cells (APC) using activating cytokines, by triggering toll-like receptors (TLRs) using microbial pathogens and by CD40 stimulation with CD40L-transfected fibroblasts. CD40 activation in the presence of IL-4 induced strongest upregulation of costimulatory and adhesion molecules on B-CLL cells and induced the production of high amounts of IL-12 by the leukemic cells. In contrast to primary B-CLL cells as stimulator cells, these malignant APCs were capable of inducing the generation of B-CLL-reactive CD8+ CTL lines and clones from HLA class I-matched donors. These CTL lines and clones recognized and killed primary B-CLL as well as patient-derived lymphoblasts, but not donor cells. These results show the feasibility of ex vivo generation of B-CLL-reactive CD8+ CTLs. This opens new perspectives for adoptive immunotherapy, following allogeneic stem cell transplantation in patients with advanced B-CLL.

Treatment with rituximab, cyclophosphamide, doxorubicin, vincristine and prednisolone is beneficial but toxic in very elderly patients with diffuse large B-cell lymphoma : a population-based cohort study on treatment, toxicity and outcome

Abstract To assess treatment strategies, toxicity and outcome in very elderly patients (aged ≥ 75 years) diagnosed with diffuse large B-cell lymphoma (DLBCL) in the rituximab era, an observational population-based cohort study was performed. From 103 patients with a median age of 81 years, data of clinical characteristics, treatment, toxicity and outcome were evaluated. Advanced stage DLBCL was documented in 74 patients. In 80 patients chemotherapy was initiated; 70 patients received rituximab, cyclophosphamide, doxorubicin, vincristine and prednisolone (R-CHOP). In this group, 39 patients completed all cycles and 30 patients achieved a complete remission. Severe chemotherapy-related toxicity occurred in 69%. Two-year overall survival was 70% for elderly patients who completed chemotherapy, 28% for those treated with incomplete or suboptimal chemotherapy and 21% for those receiving palliative radiotherapy or supportive care. In conclusion, the ability to complete R-CHOP was associated with better overall survival compared to other treatment strategies at the expense of severe treatment-related toxicity.

Early Detection and Rapid Isolation of Leukemia-Reactive Donor T Cells for Adoptive Transfer Using the IFN-γ Secretion Assay

Purpose: The poor immunogenicity of most leukemias and the lack of specificity of the donor T cells limit the in vivo effectiveness of conventional donor lymphocyte infusions in many patients suffering from persistent or recurrent leukemia after allogeneic stem cell transplantation. These limitations may be overcome by the adoptive transfer of in vitro generated leukemia-reactive T cells. Although the potential clinical efficacy of this approach has been shown previously, lack of reproducibility of the procedure and the inability to show persistence and survival of the transferred T cells hampered further clinical application. The purpose of this study was to develop a new, broadly applicable strategy for the efficient generation and isolation of leukemia-reactive T cells with a better probability to survive and expand in vivo. Experimental Design: Myeloid and B-cell leukemias were modified into professional immunogenic antigen-presenting cells, and used to stimulate HLA-matched donor T cells. After two stimulations, responding donor T cells were isolated based on their secretion of IFN-γ and tested for their capacity to recognize and kill the primary leukemia. Results: Using one universal stimulation and isolation protocol for various forms of leukemia, T-cell populations containing high frequencies of leukemia-reactive T cells could reproducibly be generated and early isolated under mild stimulatory conditions. Isolated T cells still had high proliferative potential and their reactivity seemed to be restricted to cells of the patients hematopoiesis. Conclusion: We here show a new robust procedure for the generation and isolation of leukemia-reactive T cells for adoptive transfer.

Comorbidity is an independent prognostic factor in patients with advanced-stage diffuse large B-cell lymphoma treated with R-CHOP : a population-based cohort study

An observational population‐based cohort study was performed to investigate the role of comorbidity on outcome and treatment‐related toxicity in patients with newly diagnosed advanced‐stage diffuse large B‐cell lymphoma (DLBCL) treated with R‐CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone). Data for the clinical characteristics of 154 patients (median age 69 years), including Charlson Comorbidity Index (CCI), treatment, toxicity and outcome were evaluated. Forty‐five percent of the patients had an International Prognistic index ≥3 and 16% had a CCI ≥2. The planned R‐CHOP schedule was completed by 84% and 75% reached complete remission (CR). In those with CCI ≥2, 67% completed treatment with 46% CR. In patients with a CCI <2, overall survival (OS) after 1, 2 and 5 years was 84%, 79% and 65% respectively and it was 64%, 48% and 48% for those with CCI ≥2. Grade III/IV toxicity was documented in 53%, most frequently febrile neutropenia (27%) and infections (23%). In multivariate analysis CCI ≥2 and IPI ≥3 were independent risk indicators for OS and grade III/IV toxicity. In conclusion, comorbidity is an independent risk indicator for worse OS in patients with advanced DLBCL treated with R‐CHOP by interference with intensive treatment schedules and more grade III/IV toxicity. Future studies are warranted to determine the optimal treatment approach in patients with significant comorbidities.

Primary Allogeneic T-Cell Responses against Mantle Cell Lymphoma Antigen-Presenting Cells for Adoptive Immunotherapy after Stem Cell Transplantation

Purpose: In patients treated with allogeneic stem cell transplantation for advanced mantle cell lymphoma (MCL), complete sustained remissions have been observed illustrating susceptibility of MCL cells to a graft-versus-lymphoma effect. To potentiate this graft-versus-lymphoma effect, adoptive transfer of in vitro selected MCL-specific CTL can be an attractive approach. The lack of expression of costimulatory molecules on MCL cells hampers the generation of MCL-reactive T-cell responses. The purpose of this study was to modify MCL cells into antigen-presenting cells (APC) and to use these MCL-APCs to induce allogeneic MCL-reactive T-cell responses. Experimental Design: Interleukin (IL)-4, IL-10, CpG, and CD40 activation were tested for their capacity to up-regulate costimulatory molecules on MCL cells. Primary MCL cells or the modified MCL-APCs were then used to evaluate the induction of MCL-reactive T-cell responses in HLA-matched donors. Results: Ligation of CD40 on MCL cells was essential to up-regulate costimulatory molecules and to induce production of high amounts of IL-12. In contrast to primary MCL cells, MCL-APC cells as stimulators were capable of inducing CD8+ CTL lines from HLA class I–matched donors. High numbers of CTL clones could be generated capable of efficiently killing the primary MCL cells and MCL-APC but not donor-specific targets. Conclusion: These results show the feasibility to generate primary allogeneic T-cell responses against MCL-APC, and may provide new immunotherapeutic tools to further exploit the graft-versus-lymphoma effect following allogeneic stem cell transplantation in patients with MCL.

Clinical challenges related to novel oral anticoagulants: Drug-drug interactions and monitoring

The introduction of the novel oral anticoagulants (NOAC), such as the direct Factor Xa-inhibitors rivaroxaban and apixaban and the thrombin-inhibitor dabigatran, have provided an effective and safe alternative to vitamin K antagonists (VKA) for the prevention of thromboembolic complications in

Combination therapy with bortezomib, continuous low-dose cyclophosphamide and dexamethasone followed by one year of maintenance treatment for relapsed multiple myeloma patients

Combination therapy for longer periods but at low dose might be an effective and tolerable manner to treat patients with relapsed multiple myeloma (MM). We used bortezomib, dexamethasone and low‐dose oral cyclophosphamide as an induction regimen, followed by 1 year of maintenance consisting of bortezomib and cyclophosphamide. Relapsed MM patients were treated with six cycles of bortezomib twice weekly, cyclophosphamide 50 mg daily and dexamethasone. Maintenance therapy was given for 1 year. Primary endpoints were toxicity during re‐induction and maintenance therapy. Secondary endpoints were response to treatment and progression‐free (PFS) and overall survival (OS). This study included 59 patients. Myelosuppression and neuropathy were the most common side effects. Median follow‐up was 27·1 (0·46–54·4) months with an overall response of 71%, and a very good partial response or more of 33%. During maintenance, improved responsiveness was observed in 19% of the patients. The median PFS was 18·4 months (range 0·13–43·5) and the median OS was 28·1 months (range 0·13–54·4). In conclusion, our study demonstrates that treatment with bortezomib, dexamethasone and low‐dose cyclophosphamide is an effective and manageable regimen. Adding 1 year of maintenance was feasible, with limited side effects and an increased response rate.