Clinical impact of immunophenotypic remission after allogeneic hematopoietic cell transplantation in multiple myeloma

Outcomes in newly diagnosed young or high-risk myeloma patients receiving tandem autologous/allogeneic transplant followed by bortezomib maintenance: a phase II study

Despite novel drugs and autologous HCT, MM remains incurable, with short survival in patients with poor biological characteristics. Allo HCT may be curative in some patients but is hampered by high rates of toxicity and relapse. We hypothesized that bortezomib (BTZ), with its anti-myeloma and immunologic properties, could improve PFS and cGVHD after allo HCT in newly diagnosed MM patients. In this prospective phase II study, we included 39 young (≤50 years) and high-risk patients who received a tandem auto-allo HCT followed by BTZ. Patients had prospective minimal residual disease (MRD) evaluations using Next-Generation Flow cytometry prior to allo HCT, prior BTZ and every 3 months for 2 years. With a median follow-up of 48 months, we report PFS and OS at 5 years of 41% and 80%, with a non-relapse mortality of 12%. Incidences of grade II-IV aGVHD at 12 months and moderate/severe cGVHD at 2 years were 26% and 57%. In a multivariate analysis model including cytogenetics, ISS and MRD status, MRD positivity prior to allo HCT (HR 3.75, p = 0.037), prior BTZ (HR 11.3, p = 0.018) and 3 months post-BTZ initiation (HR 9.7, p = 0.001) was highly predictive of progression. Peritransplant MRD assessment thus strongly predicts disease progression.

Long-term follow up of tandem autologous-allogeneic hematopoietic cell transplantation for multiple myeloma

We previously reported initial results in 102 multiple myeloma (MM) patients treated with sequential high-dose melphalan and autologous hematopoietic cell transplantation followed by 200 cGy total body irradiation with or without fludarabine 90 mg/m² and allogeneic hematopoietic cell transplantation. Here we present long-term clinical outcomes among the 102 initial patients and among 142 additional patients, with a median follow up of 8.3 (range 1.0-18.1) years. Donors included human leukocyte antigen identical siblings (n=179) and HLA-matched unrelated donors (n=65). A total of 209 patients (86%) received tandem autologous-allogeneic upfront, while thirty-five patients (14%) had failed a previous autologous hematopoietic cell transplantation before the planned autologous-allogeneic transplantation. Thirty-one patients received maintenance treatment at a median of 86 days (range, 61-150) after allogeneic transplantation. Five-year rates of overall survival (OS) and progression-free survival (PFS) were 54% and 31%, respectively. Ten-year OS and PFS were 41% and 19%, respectively. Overall non-relapse mortality was 2% at 100 days and 14% at five years. Patients with induction-refractory disease and those with high-risk biological features experienced shorter OS and PFS. A total of 152 patients experienced disease relapse and 117 of those received salvage treatment. Eighty-three of the 117 patients achieved a clinical response, and for those, the median duration of survival after relapse was 7.8 years. Moreover, a subset of patients who became negative for minimal residual disease (MRD) by flow cytometry experienced a significantly lower relapse rate as compared with MRD-positive patients (P=0.03). Our study showed that the graft-versus-myeloma effect after non-myeloablative allografting allowed long-term disease control in standard and high-risk patient subsets. Ultra-high-risk patients did not appear to benefit from tandem autologous/allogeneic hematopoietic cell transplantation because of early disease relapse. Incorporation of newer anti-MM agents into the initial induction treatments before tandem hematopoietic cell transplantation and during maintenance might improve outcomes of ultra-high-risk patients. Clinical trials included in this study are registered at: clinicaltrials.gov identifiers: 00075478, 00005799, 01251575, 00078858, 00105001, 00027820, 00089011, 00003196, 00006251, 00793572, 00054353, 00014235, 00003954.

Allogeneic Hematopoietic Cell Transplantation for Myeloma: When and in Whom Does It Work

The growing list of available therapies for patients with multiple myeloma has resulted in tremendously high response rates and prolonged survival. However, the cure remains elusive. A continued effort at developing strategies to utilize all available treatment modalities in the most effective manner is needed. Allogeneic hematopoietic cell transplantation (allo-HCT) is a robust platform, associated with high response rates, and provides a unique foundation on which immune therapies and novel agents can be employed to improve clinical outcomes. Patients with high-risk myeloma and those relapsing after novel agent-based therapies or early after an autologous HCT should be considered for allo-HCT, ideally in a clinical trial setting. Results from several ongoing studies are expected to provide important information that will help determine the place of allo-HCT in the myeloma treatment algorithm.

Phase I study of cord blood-derived natural killer cells combined with autologous stem cell transplantation in multiple myeloma

Multiple myeloma (MM) is a disease with known immune dysregulation. Natural killer (NK) cells have shown preclinical activity in MM. We conducted a first-in-human study of umbilical cord blood-derived (CB) NK cells for MM patients undergoing high dose chemotherapy and autologous haematopoietic stem cell transplantation (auto-HCT). Patients received lenalidomide (10 mg) on days -8 to -2, melphalan 200 mg/m2 on day -7, CB-NK cells on day -5 and auto-HCT on day 0. Twelve patients were enrolled, three on each of four CB-NK cell dose levels: 5 × 106 , 1 × 107 , 5 × 107 and 1 × 108 CB-NK cells/kg. Ten patients had either high-risk chromosomal changes or a history of relapsed/progressed disease. There were no infusional toxicities and no graft-versus-host disease. One patient failed to engraft due to poor autologous graft quality and was rescued with a back-up autologous graft. Overall, 10 patients achieved at least a very good partial response as their best response, including eight with near complete response or better. With a median follow-up of 21 months, four patients have progressed or relapsed, two of whom have died. CB-NK cells were detected in vivo in six patients, with an activated phenotype (NKG2D+ /NKp30+ ). These data warrant further development of this novel cellular therapy.

Stem cell transplantation in multiple myeloma and other plasma cell disorders (report from an EBMT preceptorship meeting)

The European Society for Blood and Marrow Transplantation Chronic Malignancies Working Party held a preceptorship meeting in Turin, Italy on 25-26 September 2014, to discuss the role of stem cell transplantation (SCT) in the treatment of multiple myeloma and other plasma cell disorders. Scientists and clinicians working in the field gathered to discuss a variety of topics including the results of recent clinical trials, basic research, the concept of minimal residual disease, and immune modulation. As individual presentations revealed, important advances have occurred in our understanding of the pathophysiology of myeloma and the role that SCT, along with other forms of immunotherapy, plays in treating it. Each presentation stimulated discussion and exchange of ideas among the attendants. We decided to summarize and, importantly, to update the meeting proceedings in this review to share stimulating discussions and ideas on potentially novel treatment strategies among clinicians.

Allogeneic stem cell transplantation in multiple myeloma: immunotherapy and new drugs

INTRODUCTION

Autologous (auto) stem cell transplantation (SCT) and the development of new drugs have improved the survival of multiple myeloma (MM) patients. By contrast, though potentially curative, the use of allogeneic (allo)-SCT is controversial.

AREAS COVERED

A review has been conducted to examine the current evidence for the use of allo-SCT in MM. We have examined novel cell therapies that may be exploited to induce myeloma-specific immune responses including the new promising frontier of chimeric antigen receptor (CAR)-T and -natural killer (NK) cells.

EXPERT OPINION

One of the major controversies facing researchers in exploring the allo approach is the remarkable recent treatment improvement observed with second- and third-generation proteasome inhibitors and immunomodulatory drugs, monoclonal antibodies and deacetylase inhibitors. Despite these great advances, the disease remains to be incurable and allo-SCT may still play a role in the cure of MM. We think that allo-SCT conserves a role in MM and its curative potential in high-risk patients should be explored in the setting of control clinical trials. Novel cell therapies such as CAR technologies may open new avenues of research toward a potential cure. Data from currently ongoing prospective studies will be helpful to clarify pending clinical questions.