Our results show that age, hemorrhagic diathesis, and initial leukocyte count are prognostic factors for APL treated with ATRA followed by intensive chemotherapy.

Wilms' tumor 1 (WT1) is constantly expressed in leukemic cells of acute leukemia and myelodysplastic syndrome (MDS). A T-cell receptor (TCR) that specifically reacts with WT1 peptide in the context of HLA-A*24:02 has been identified. We conducted a first-in-human trial of TCR-gene transduced T-cell (TCR-T-cell) transfer in patients with refractory acute myeloblastic leukemia (AML) and high-risk MDS to investigate the safety and cell kinetics of the T cells. The WT1-specific TCR-gene was transduced to T cells using a retroviral vector encoding small interfering RNAs for endogenous TCR genes. The T cells were transferred twice with a 4-week interval in a dose-escalating design. After the second transfer, sequential WT1 peptide vaccines were given. Eight patients, divided into 2 dose cohorts, received cell transfer. No adverse events of normal tissue were seen. The TCR-T cells were detected in peripheral blood for 8 weeks at levels proportional to the dose administered, and in 5 patients, they persisted throughout the study period. The persisting cells maintained ex vivo peptide-specific immune reactivity. Two patients showed transient decreases in blast counts in bone marrow, which was associated with recovery of hematopoiesis. Four of 5 patients who had persistent T cells at the end of the study survived more than 12 months. These results suggest WT1-specific TCR-T cells manipulated by ex vivo culture of polyclonal peripheral lymphocytes survived in vivo and retained the capacity to mount an immune reaction to WT1. This trial was registered at www.umin.ac.jp as #UMIN000011519.

Purpose: Preparative lymphodepletion, the temporal ablation of the immune system, has been reported to promote persistence of transferred cells along with increased rates of tumor regression in patients treated with adoptive T-cell therapy. However, it remains unclear whether lymphodepletion is indispensable for immunotherapy with T-cell receptor (TCR) gene-engineered T cells.Experimental Design: We conducted a first-in-man clinical trial of TCR gene-transduced T-cell transfer in patients with recurrent MAGE-A4-expressing esophageal cancer. The patients were given sequential MAGE-A4 peptide vaccinations. The regimen included neither lymphocyte-depleting conditioning nor administration of IL2. Ten patients, divided into 3 dose cohorts, received T-cell transfer.Results: TCR-transduced cells were detected in the peripheral blood for 1 month at levels proportional to the dose administered, and in 5 patients they persisted for more than 5 months. The persisting cells maintained ex vivo antigen-specific tumor reactivity. Despite the long persistence of the transferred T cells, 7 patients exhibited tumor progression within 2 months after the treatment. Three patients who had minimal tumor lesions at baseline survived for more than 27 months.Conclusions: These results suggest that TCR-engineered T cells created by relatively short-duration in vitro culture of polyclonal lymphocytes in peripheral blood retained the capacity to survive in a host. The discordance between T-cell survival and tumor regression suggests that multiple mechanisms underlie the benefits of preparative lymphodepletion in adoptive T-cell therapy.

Purpose: We developed a complex of tumor antigen protein with a novel nanoparticle antigen delivery system of cholesteryl pullulan (CHP). To target HER2 antigen, we prepared truncated HER2 protein 1-146 (146HER2) complexed with CHP, the CHP-HER2 vaccine. We designed a clinical study to assess the safety of the vaccine and HER2-specific T-cell immune responses measured by the newly developed enzyme-linked immunospot assay with mRNA-transduced phytohemagglutinin-stimulated CD4 + T cells in HLA-A2402-positive patients with therapyrefractory HER2-expressing cancers. Experimental Design: Nine patients with various types of solid tumors were enrolled. Each patient was s.c. vaccinated biweekly with 300 Ag of CHP-HER2 vaccine for three times followed by booster doses. HER2-specific T-cell responses were evaluated by enzyme-linked immunospot assay by targeting autologous phytohemagglutinin-stimulated CD4 + T cells transduced with 146HER2-encoding mRNA to cover both identified peptides and unknown epitopes for MHC class I and class II that might exist in the sequence of the vaccine protein.Results: CHP-HER2 vaccine was well tolerated; the only adverse effect was grade1transient skin reaction at the sites of vaccination. HER2-specific CD8 + and/or CD4 + T-cell immune responses were detected in five patients who received four to eight vaccinations, among whom bothT-cell responses were detected in these patients. In four patients with CD8 + T-cell responses, two patients reacted to previously identified HER2 63-71 peptide and the other two reacted only to 146HER2 mRNA-transduced cells. Conclusions: CHP-HER2 vaccine was safe and induced HER2-specific CD8 + and/or CD4 + T-cell immune responses.

Analyses of our clinical trial showed that the use of BHAC in remission-induction therapy and in consolidation therapy resulted in poorer CR and EFS rates in adult AML patients compared with the use of cytarabine at the doses and schedules tested. Immunotherapy with ubenimex after the end of all chemotherapy did not improve DFS.

BackgroundCholesteryl pullulan (CHP) is a novel antigen delivery system for cancer vaccines. This study evaluated the safety, immune responses and clinical outcomes of patients who received the CHP-NY-ESO-1 complex vaccine, Drug code: IMF-001.MethodsPatients with advanced/metastatic esophageal cancer were enrolled and subcutaneously vaccinated with either 100 μg or 200 μg of NY-ESO-1 protein complexed with CHP. The primary endpoints were safety and humoral immune responses, and the secondary endpoint was clinical efficacy.ResultsA total of 25 patients were enrolled. Thirteen and twelve patients were repeatedly vaccinated with 100 μg or 200 μg of CHP-NY-ESO-1 with a median of 8 or 9.5 doses, respectively. No serious adverse events related to the vaccine were observed. Three out of 13 patients in the 100-μg cohort and 7 out of 12 patients in the 200-μg cohort were positive for anti-NY-ESO-1 antibodies at baseline. In the 100-μg cohort, an antibody response was observed in 5 out of 10 pre-antibody-negatives patients, and the antibody levels were augmented in 2 pre-antibody-positive patients after vaccination. In the 200-μg cohort, all 5 pre-antibody-negative patients became seropositive, and the antibody level was amplified in all 7 pre-antibody-positive patients. No tumor shrinkage was observed. The patients who received 200 μg of CHP-NY-ESO-1 survived longer than patients receiving 100 μg of CHP-NY-ESO-1, even those who exhibited unresponsiveness to previous therapies or had higher tumor burdens.ConclusionsThe safety and immunogenicity of CHP-NY-ESO-1 vaccine were confirmed. The 200 μg dose more efficiently induced immune responses and suggested better survival benefits. (Clinical trial registration number NCT01003808).

Background. It was assessed whether addition of vincristine (VCR) to remission induction therapy would increase the complete remission (CR) rate, and, secondarily, whether 12 courses of maintenance—intensification therapy would produce longer survival than 4 courses in adult acute myeloid leukemia (AML). Methods. A randomized comparison of individualized induction therapy was conducted between daunorubicin, behenoyl cytarabine, 6‐mercaptopurine, and prednisolone with or without VCR. After 3 courses of intensive consolidation therapy, maintenance—intensification therapy was randomized to 4 or 12 courses given every 6 weeks. Results. Of 265 patients registered, 252 were evaluable. CR was obtained in 78%; 80% in 205 patients of age younger than 60 years, and 65% in 47 of age 60 years or older. Addition of VCR reduced the CR rate significantly (84% to 70%, P = 0.007). Predicted 4‐year survival, continuing CR, and disease‐free survival (DFS) rates of 196 CR patients are 45%, 41%, and 35%, respectively. Patients receiving 12 courses of maintenance—intensification showed better DFS. By multivariate analyses, significant factors for achievement of CR were performance status 0 to 2, age younger than 60 years, and no VCR; and those for longer DFS were achievement of CR by one course, age younger than 50 years, and French—American—British (FAB) classification M3 or M5. Among 131 patients randomized to the maintenance, the administration of 12 courses was the most important factor (P = 0.0040) for longer DFS, followed by FAB M3 or M5, and by achievement of CR by one course. Conclusions. Addition of VCR in remission induction therapy was harmful, and longer intensive maintenance therapy prolonged DFS in adult AML.

The CHP-HER2 vaccine, comprising truncated 146HER2 protein complexed with nanogels of cholesteryl pullulan (CHP), is a novel protein antigen vaccine that elicits 146HER2-specific CD8 + and CD4