Joanne Filicko-O'Hara

A 2-step approach to myeloablative haploidentical stem cell transplantation: a phase 1/2 trial performed with optimized T-cell dosing.

Studies of haploidentical hematopoietic stem cell transplantation (HSCT) have identified threshold doses of T cells below which severe GVHD is usually absent. However, little is known regarding optimal T-cell dosing as it relates to engraftment, immune reconstitution, and relapse. To begin to address this question, we developed a 2-step myeloablative approach to haploidentical HSCT in which 27 patients conditioned with total body irradiation (TBI) were given a fixed dose of donor T cells (HSCT step 1), followed by cyclophosphamide (CY) for T-cell tolerization. A CD34-selected HSC product (HSCT step 2) was infused after CY. A dose of 2 × 10(8)/kg of T cells resulted in consistent engraftment, immune reconstitution, and acceptable rates of GVHD. Cumulative incidences of grade III-IV GVHD, nonrelapse mortality (NRM), and relapse-related mortality were 7.4%, 22.2%, and 29.6%, respectively. With a follow-up of 28-56 months, the 3-year probability of overall survival for the whole cohort is 48% and 75% in patients without disease at HSCT. In the context of CY tolerization, a high, fixed dose of haploidentical T cells was associated with encouraging outcomes, especially in good-risk patients, and can serve as the basis for further exploration and optimization of this 2-step approach. This study is registered at www.clinicaltrials.gov as NCT00429143.

A Two-Step Haploidentical Versus a Two-Step Matched Related Allogeneic Myeloablative Peripheral Blood Stem Cell Transplantation

Haploidentical stem cell transplantation (SCT) offers a transplantation option to patients who lack an HLA-matched donor. We developed a 2-step approach to myeloablative allogeneic hematopoietic stem cell transplantation for patients with haploidentical or matched related (MR) donors. In this approach, the lymphoid and myeloid portions of the graft are administered in 2 separate steps to allow fixed T cell dosing. Cyclophosphamide is used for T cell tolerization. Given a uniform conditioning regimen, graft T cell dose, and graft-versus-host disease (GVHD) prophylaxis strategy, we compared immune reconstitution and clinical outcomes in patients undergoing 2-step haploidentical versus 2-step MR SCT. We retrospectively compared data on patients undergoing a 2-step haploidentical (n = 50) or MR (n = 27) peripheral blood SCT for high-risk hematological malignancies and aplastic anemia. Both groups received myeloablative total body irradiation conditioning. Immune reconstitution data included flow cytometric assessment of T cell subsets at day 28 and 90 after SCT. Both groups showed comparable early immune recovery in all assessed T cell subsets except for the median CD3/CD8 cell count, which was higher in the MR group at day 28 compared with that in the haploidentical group. The 3-year probability of overall survival was 70% in the haploidentical group and 71% in the MR group (P = .81), while the 3-year progression-free survival was 68% in the haploidentical group and 70% in the MR group (P = .97). The 3-year cumulative incidence of nonrelapse mortality was 10% in the haploidentical group and 4% in the MR group (P = .34). The 3-year cumulative incidence of relapse was 21% in the haploidentical group and 27% in the MR group (P = .93). The 100-day cumulative incidence of overall grades II to IV acute GVHD was higher in the haploidentical group compared with that in the MR group (40% versus 8%, P < .001), whereas the grades III and IV acute GVHD was not statistically different between both groups (haploidentical, 6%; MR, 4%; P = .49). The cumulative incidence of cytomegalovirus reactivation was also higher in the haploidentical group compared to the MR group (haploidentical, 68%; MR, 19%; P < .001). There were no deaths from GVHD in either group. Using an identical conditioning regimen, graft T cell dose, and GVHD prophylaxis strategy, comparable early immune recovery and clinical outcomes were observed in the 2-step haploidentical and MR SCT recipients.

Overlap between in vitro donor antihost and in vivo posttransplantation TCR Vβ use: a new paradigm for designer allogeneic blood and marrow transplantation

Following allogeneic blood and marrow transplantation (BMT), mature donor T cells can enhance engraftment, counteract opportunistic infections, and mount graft-versus-tumor (GVT) responses, but at the risk of developing graft-versus-host disease (GVHD). With the aim of separating the beneficial effects of donor T cells from GVHD, one approach would be to selectively deplete subsets of alloreactive T cells in the hematopoietic cell inoculum. In this regard, TCR Vbeta repertoire analysis by CDR3-size spectratyping can be a powerful tool for the characterization of alloreactive T-cell responses. We investigated the potential of this spectratype approach by comparing the donor T-cell alloresponses generated in vitro against patient peripheral blood lymphocytes (PBLs) with those detected in vivo posttransplantation. The results indicated that for most Vbeta families that exhibited alloreactive CDR3-size skewing, there was a robust overlap between the in vitro antipatient and in vivo spectratype histograms. Thus, in vitro spectratype analysis may be useful for determining the alloreactive T-cell response involved in GVHD development and, thereby, could serve to guide select Vbeta family depletion for designer transplants to improve outcomes.

Antiviral Responses following L-Leucyl-L-Leucine Methyl Esther (LLME)-Treated Lymphocyte Infusions: Graft-versus-Infection without Graft-versus-Host Disease

Although allogeneic hematopoietic progenitor cell transplant (HPCT) is curative therapy for many disorders, it is associated with significant morbidity and mortality, which can be related to graft-versus-host disease (GVHD) and the immunosuppressive measures required for its prevention and/or treatment. Whether the immunosuppression is pharmacologic or secondary to graft manipulation, the graft recipient is left at increased risk of the threatening opportunistic infection. Refractory viral diseases in the immunocompromised host have been treated by infusion of virus-specific lymphotyces and by unmanipulated donor lymphocyte infusion (DLI) therapy. L-leucyl-L-leucine methyl ester (LLME) is a compound that induces programmed cell death of natural killer (NK) cells, monocytes, granulocytes, most CD8(+) T cells, and a small fraction of CD4(+) T cells. We have undertaken a study of the use of LLME-treated DLI following T cell-depleted allogeneic HPCT, specifically to aid with immune reconstitution. In this ongoing clinical trial, we have demonstrated the rapid emergence of virus-specific responses following LLME DLI with minimal associated GVHD. This paper examines the pace of immune recovery and the rapid development of antiviral responses in 6 patients who developed viral infections during the time period immediately preceding or coincident with the administration of the LLME DLI.

Acquired uniparental disomy in chromosome 6p as a feature of relapse after T-cell replete haploidentical hematopoietic stem cell transplantation using cyclophosphamide tolerization.

Acquired uniparental disomy in chromosome 6p as a feature of relapse after T-cell replete haploidentical hematopoietic stem cell transplantation using cyclophosphamide tolerization

Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma With Pancytopenia and Chylothorax

t r n c s p o c C C f e m t t p c S m p t r v o 7 a t p c a t e M o m b T n C m i ( t l o p At times we encounter clinical problems for which there are no directly applicable evidence-based solutions, but we are compelled by circumstances to act. When doing so we rely on related evidence, general principles of best medical practice, and our experience. Each ”Current Clinical Practice” feature article in Seminars in Oncology describes such a challenging presentation and offers treatment approaches from selected specialists. We invite readers’ comments and questions, which, with your approval, will be published in subsequent issues of the Journal. It is hoped that sharing our views and experiences will better inform our management decisions when we next encounter similar challenging patients. Please send your comments on the articles, your challenging cases, and your treatment successes to me at Gloria. Morris@hemonc1.com. I look forward to a lively discussion.

Final outcomes of escalated melphalan 280 mg/m 2 with amifostine cytoprotection followed autologous hematopoietic stem cell transplantation for multiple myeloma: high CR and VGPR rates do not translate into improved survival

The most common preparative regimen for autologous transplantation (ASCT) in myeloma (MM) consists of melphalan 200 mg/m2 (MEL 200). Higher doses of melphalan 220–260 mg/m2, although relatively well tolerated, have not shown significant improvement in clinical outcomes. Several approaches have been pursued in the past to improve CR rates, including poly-chemotherapy preparative regimens, tandem ASCT, consolidation, and/or maintenance therapy. Since there is a steep dose–response effect for intravenous melphalan, we evaluated an alternative single ASCT strategy using higher-dose melphalan at 280 mg/m2 (MEL 280) with amifostine as a cytoprotectant as the maximum tolerated dose determined in an earlier phase I dose escalation trial. We report the final long-term outcomes of MM patients who underwent conditioning with MEL 280 with amifostine cytoprotection followed by ASCT. Although the complete response rate was quite high in the era pre-dating the routine use of novel therapies (proteasome inhibitors, immunomodulatory agents) (49%), the progression-free survival was a disappointing 22 months. The implications of this dichotomy between the excellent depth of ASCT response and progression-free survival are discussed.