A Belgian consensus protocol for autologous hematopoietic stem cell transplantation in multiple sclerosis

Multiple sclerosis is considered to be an immune mediated inflammatory disorder of the central nervous system. It mainly affects young, socioeconomic active patients. Although our armamentarium for this disease has significantly evolved in recent years some patients remain refractory to conventional therapies. In these cases, autologous hematopoietic stem cell transplantation can be considered as a therapeutic option. Decreasing morbidity, mortality, and increasing patient awareness have led to rising inquiry by our patients about this treatment option. With the aim of a standardized protocol and data registration, a Belgian working party on stem cell therapy in multiple sclerosis was established. In this paper, we report the consensus protocol of this working party on autologous hematopoietic stem cell transplantation in multiple sclerosis.

A predictive model for risk of early grade ≥ 3 infection in patients with multiple myeloma not eligible for transplant: analysis of the FIRST trial

Infections are a major cause of death in patients with multiple myeloma. A post hoc analysis of the phase 3 FIRST trial was conducted to characterize treatment-emergent (TE) infections and study risk factors for TE grade ≥ 3 infection. The number of TE infections/month was highest during the first 4 months of treatment (defined as early infection). Of 1613 treated patients, 340 (21.1%) experienced TE grade ≥ 3 infections in the first 18 months and 56.2% of these patients experienced their first grade ≥ 3 infection in the first 4 months. Risk of early infection was similar regardless of treatment. Based on the analyses of data in 1378 patients through multivariate logistic regression, a predictive model of first TE grade ≥ 3 infection in the first 4 months retained Eastern Cooperative Oncology Group performance status and serum β₂-microglobulin, lactate dehydrogenase, and hemoglobin levels to define high- and low-risk groups showing significantly different rates of infection (24.0% vs. 7.0%, respectively; P < 0.0001). The predictive model was validated with data from three clinical trials. This predictive model of early TE grade ≥ 3 infection may be applied in the clinical setting to guide infection monitoring and strategies for infection prevention.

WT1-targeted dendritic cell vaccination as a postremission treatment to prevent or delay relapse in acute myeloid leukemia

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Background: Vaccination with tumor antigen-loaded dendritic cells (DC) holds promise for the adjuvant treatment of cancer. Methods: In a phase I/II trial, we investigated the effect of autologous DC vaccination in 17 patients with acute myeloid leukemia (AML) in remission but at very high risk of full relapse. Wilms’ tumor 1 protein (WT1) was chosen as immunotherapeutic target and introduced into the DC by mRNA electroporation. We are continuing a phase II trial, which is still recruiting. Results: Two out of 3 patients, who were in partial remission with chemotherapy-refractory disease, were brought into complete remission following 4 biweekly intradermal injections of WT1 mRNA-electroporated DC. In those 2 patients as well as in 6 other patients who were in complete remission but who had molecularly demonstrable residual disease, there was a return to normal of the AML-associated WT1 mRNA tumor marker following DC vaccination, compatible with reaching clinical and molecular remission in 8/17 patients. Among the 8 responders, there have been 2 relapses and 2 deaths. Of the 9 non-responders, 8 have relapsed and 7 have died. Of the 2 patients in partial remission who were brought into complete remission by DC vaccination, 1 has died following relapse. Median overall survival was 6 months in non-responders and 52 months in responders (p=0.0007). Median relapse-free survival was 3 months in non-responders as compared to 47 months in responders (p<0.0001). Clinical responses overall were correlated with elevated levels of activated natural killer (NK) cells post-vaccination. Long-term clinical responses, lasting for at least 3 years, were significantly correlated with an increase in polyepitope WT1-specific tetramer+ CD8+ T-cell frequencies. Conclusions: DC-based immunotherapy elicits both innate (NK) and adaptive (T cells) cellular responses correlated with clinical benefit. WT1 mRNA-transfected DC emerge as a feasible and effective strategy to control residual disease in AML, in particular as a post-remission treatment to prevent full relapse.

Induction of complete and molecular remissions in acute myeloid leukemia by Wilms' tumor 1 antigen-targeted dendritic cell vaccination

Active immunization using tumor antigen-loaded dendritic cells holds promise for the adjuvant treatment of cancer to eradicate or control residual disease, but so far, most dendritic cell trials have been performed in end-stage cancer patients with high tumor loads. Here, in a phase I/II trial, we investigated the effect of autologous dendritic cell vaccination in 10 patients with acute myeloid leukemia (AML). The Wilms' tumor 1 protein (WT1), a nearly universal tumor antigen, was chosen as an immunotherapeutic target because of its established role in leukemogenesis and superior immunogenic characteristics. Two patients in partial remission after chemotherapy were brought into complete remission after intradermal administration of full-length WT1 mRNA-electroporated dendritic cells. In these two patients and three other patients who were in complete remission, the AML-associated tumor marker returned to normal after dendritic cell vaccination, compatible with the induction of molecular remission. Clinical responses were correlated with vaccine-associated increases in WT1-specific CD8+ T cell frequencies, as detected by peptide/HLA-A*0201 tetramer staining, and elevated levels of activated natural killer cells postvaccination. Furthermore, vaccinated patients showed increased levels of WT1-specific IFN-gamma-producing CD8+ T cells and features of general immune activation. These data support the further development of vaccination with WT1 mRNA-loaded dendritic cells as a postremission treatment to prevent full relapse in AML patients.

Management of Kaposi's sarcoma in resource-limited settings in the era of HAART

The introduction of highly active antiretroviral therapy (HAART) has changed the natural history of AIDS-associated Kaposi's sarcoma (KS). Although the use of HAART remains limited in low-resource settings, there are global initiatives to make these drugs available to several millions of HIV-infected persons. While there are multiple reports of KS regression during HAART with or without chemotherapy, there is little documentation on KS management in resource-limited settings. In this paper we review current KS treatments available worldwide and discuss the implications of the increased access to antiretrovirals for KS treatment strategies in resource-limited settings.