Phase I/II trial of GN-BVC, a gemcitabine and vinorelbine-containing conditioning regimen for autologous hematopoietic cell transplantation in recurrent and refractory hodgkin lymphoma

Anti-CD25 radioimmunotherapy with BEAM autologous hematopoietic cell transplantation conditioning in Hodgkin lymphoma

High-risk relapsed or refractory (R/R) classical Hodgkin lymphoma (HL) is associated with poor outcomes after conventional salvage therapy and autologous hematopoietic cell transplantation (AHCT). Post-AHCT consolidation with brentuximab vedotin (BV) improves progression-free survival (PFS), but with increasing use of BV early in the treatment course, the utility of consolidation is unclear. CD25 is often expressed on Reed-Sternberg cells and in the tumor microenvironment in HL, and we hypothesized that the addition of 90Y-antiCD25 (aTac) to carmustine, etoposide, cytarabine, melphalan (BEAM) AHCT would be safe and result in a transplantation platform that is agnostic to prior HL-directed therapy. Twenty-five patients with high-risk R/R HL were enrolled in this phase 1 dose-escalation trial of aTac-BEAM. Following an imaging dose of 111In-antiCD25, 2 patients had altered biodistribution, and a third developed an unrelated catheter-associated bacteremia; therefore, 22 patients ultimately received therapeutic 90Y-aTac-BEAM AHCT. No dose-limiting toxicities were observed, and 0.6 mCi/kg was deemed the recommended phase 2 dose, the dose at which the heart wall would not receive >2500 cGy. Toxicities and time to engraftment were similar to those observed with standard AHCT, though 95% of patients developed stomatitis (all grade 1-2 per Bearman toxicity scale). Seven relapses (32%) were observed, most commonly in patients with ≥3 risk factors. The estimated 5-year PFS and overall survival probabilities among 22 evaluable patients were 68% and 95%, respectively, and non-relapse mortality was 0%. aTac-BEAM AHCT was tolerable in patients with high-risk R/R HL, and we are further evaluating the efficacy of this approach in a phase 2 trial. This trial was registered at www.clinicaltrials.gov as #NCT01476839.

FDG PET for Assessment of Autologous Stem Cell Transplantation

The appropriate selection of patients to undergo hematopoietic stem cell transplant (HSCT) is critical due to the risk of treatment-related morbidity and mortality. The prognostic value of FDG-PET/CT in response assessment in hematologic malignancies is well-established and has led to numerous investigations into the role of FDG-PET/CT in the evaluation of patients in the setting of HSCT. This article discusses the most common indications for autologous stem cell transplant (autoSCT) in which FDG-PET/CT has been evaluated, including for lymphoma and multiple myeloma. For relapsed/refractory Hodgkin lymphoma, achieving a negative FDG-PET/CT scan, regardless of the number of the regimens, prior to autoSCT is an important prognostic factor for posttransplant outcome. The data in the pretransplant setting are more variable for non-Hodgkin lymphoma. For both Hodgkin and non-Hodgkin lymphoma, studies have primarily used a visual assessment for FDG-PET/CT interpretation, with the Deauville score the current standard criteria. Optimization of thresholds for specific regimens pretransplant as well as integration of additional semiquantitative parameters to assess response remain active areas of research. For multiple myeloma, FDG-PET/CT has emerged as the recommended imaging modality of choice for assessing response to treatment. Data suggest that FDG-PET/CT may provide prognostic and predictive value for assessing outcome after autoSCT.

A Review of Autologous Stem Cell Transplantation in Lymphoma

PURPOSE OF REVIEW

Chemotherapy remains the first-line therapy for aggressive lymphomas. However, 20-30% of patients with non-Hodgkin lymphoma (NHL) and 15% with Hodgkin lymphoma (HL) recur after initial therapy. We want to explore the role of high-dose chemotherapy (HDT) and autologous stem cell transplant (ASCT) for these patients.

RECENT FINDINGS

There is some utility of upfront consolidation for-high risk/high-grade B-cell lymphoma, mantle cell lymphoma, and T-cell lymphoma, but there is no role of similar intervention for HL. New conditioning regimens are being investigated which have demonstrated an improved safety profile without compromising the myeloablative efficiency for relapsed or refractory HL. Salvage chemotherapy followed by HDT and rescue autologous stem cell transplant remains the standard of care for relapsed/refractory lymphoma. The role of novel agents to improve disease-related parameters remains to be elucidated in frontline induction, disease salvage, and high-dose consolidation or in the maintenance setting.

Risk factors predicting outcomes for primary refractory hodgkin lymphoma patients treated with salvage chemotherapy and autologous stem cell transplantation

We aimed to identify risk factors that predict functional imaging (FI) response to salvage chemotherapy and evaluate outcomes following autologous stem cell transplant (ASCT) in primary refractory Hodgkin Lymphoma (HL). From 1 October 1994 to 10 July 2015, 192 primary refractory HL patients were treated on sequential second line protocols. Event-free survival (EFS) and overall survival (OS) were calculated from the date of histological confirmation of refractory disease. Covariates were analysed for relationship with FI response and EFS. By intent-to-treat, the median EFS was 8·9 years and OS 10·4 years with 41% having positive post-salvage FI. On multivariate analysis, the presence of B symptoms and bulk ≥5 cm predicted for positive FI, with odds ratios of 2·15 and 2·03, respectively. For the 167 (87%) transplanted patients, 60% had a negative pre-ASCT FI. Median EFS and OS were not reached with at a median follow-up of 3·6 years in surviving patients. Both stage IV refractory disease and persistent FI abnormality pre- ASCT were associated with worse outcomes: 3-year EFS was 84%, 54% and 28% for zero, 1 and 2 risk factors, respectively (P < 0·001). Further studies are needed to validate our prognostic model and to determine optimal therapy for patients with multiple risk factors.

Prognostic value of pretransplant FDG-PET in refractory/relapsed Hodgkin lymphoma treated with autologous stem cell transplantation: systematic review and meta-analysis

This study aimed to systematically review the prognostic value of pretransplant ¹⁸F-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) in refractory/relapsed Hodgkin lymphoma treated with autologous stem cell transplantation (SCT). MEDLINE was systematically searched for appropriate studies. Included studies were methodologically appraised. Results of individual studies were meta-analyzed, if possible. Eleven studies, comprising a total of 745 refractory/relapsed Hodgkin lymphoma patients who underwent FDG-PET before autologous SCT, were included. The overall methodological quality of these studies was moderate. The proportion of pretransplant FDG-PET positive patients ranged between 25 and 65.2 %. Progression-free survival ranged between 0 and 52 % in pretransplant FDG-PET positive patients, and between 55 and 85 % in pretransplant FDG-PET negative patients. Overall survival ranged between 17 and 77 % in pretransplant FDG-PET positive patients, and between 78 and 100 % in FDG-PET negative patients. Based on five studies that provided sufficient data for meta-analysis, pooled sensitivity and specificity of pretransplant FDG-PET in predicting treatment failure (i.e., either progressive, residual, or relapsed disease) were 67.2 % (95 % confidence interval [CI] 58.2–75.3 %) and 70.7 % (95 % CI 64.2–76.5 %), respectively. Based on two studies that provided sufficient data for meta-analysis, pooled sensitivity and specificity of pretransplant FDG-PET in predicting death during follow-up were 74.4 % (95 % CI 58.8–86.5 %) and 58.0 % (95 % CI 49.3–66.3 %), respectively. In conclusion, the moderate quality evidence suggests pretransplant FDG-PET to have value in predicting outcome in refractory/relapsed Hodgkin lymphoma patients treated with autologous SCT. Nevertheless, a considerable proportion of pretransplant FDG-PET positive patients remains disease free and a considerable proportion of pretransplant FDG-PET negative patients develops disease relapse after autologous SCT.

Mechanistic studies on the synergistic cytotoxicity of the nucleoside analogs gemcitabine and clofarabine in multiple myeloma: relevance of p53 and its clinical implications

Hematopoietic stem cell transplantation (HSCT) is an established treatment for multiple myeloma (MM), a plasma cell malignancy. To identify an improved pretransplant conditioning regimen, we investigated the cytotoxicity of gemcitabine (Gem) and clofarabine (Clo) combinations toward MM cell lines and patient cell samples. A strong synergism of the two nucleoside analogs, when combined at their approximate IC10 concentrations, was observed. This synergism could be partly due to the observed Gem-mediated phosphorylation and activation of deoxycytidine kinase, resulting in enhanced phosphorylation of Gem and Clo. Their cytotoxicity correlated with a robust activation of the DNA damage response pathway. [Gem+Clo] decreased the mitochondrial membrane potential with a concomitant release of proapoptotic factors into the cytoplasm and nucleus and the activation of apoptosis. Exposure of MM cells to [Gem+Clo] also decreased the level of ribosomal RNA (rRNA), which might have resulted in nucleolar stress, as reported previously, and caused a p53-dependent cell death. A reduction by approximately 50% in the cytotoxicity of Gem and Clo was observed in the presence of pifithrin α, a p53 inhibitor. Furthermore, MM cell lines with mutant p53 exhibited greater resistance to Gem and Clo, supporting a role for the p53 protein in these cytotoxic responses. Our results provide a rationale for clinical trials incorporating [Gem+Clo] combinations as part of conditioning therapy for high-risk patients with MM undergoing HSCT.

Hematopoietic progenitor cells transplantation for recurrent or refractory Hodgkin's lymphoma

INTRODUCTION

Advanced-stage Hodgkin's lymphoma (HL) has become a curable disease in the majority of patients. Despite this, about 20% of these patients relapsed or are primary refractory to the first-line treatment and high-dose chemotherapy (HDC) and autologous (Auto) hematopoietic progenitor cells transplantation (HPCT) are considered a therapeutic option.

AREAS COVERED

The authors reviewed HDC and HPCT treatment strategies in recurrent or refractory HL patients, with the goal of providing an overview of this approach.

EXPERT OPINION

Patients younger than 60-65 years with relapsed disease or refractory to first-line therapy should receive a second-line chemotherapy, followed by HDC and Auto-HPCT. Progression-free and overall survival results are significantly better when a second remission or a minimal disease status is achieved before Auto-HPCT, and demonstrate that this strategy is able to cure more than half of the advanced HL patients. Myeloablative allogeneic HPCT (Allo-HPCT) has been employed in advanced phases of the disease, but there have been significant concerns due to treatment-related mortality (TRM). The safety of allogeneic transplantation has improved with the use of reduced-intensity allogeneic (RIC-Allo) HPCT strategies. Despite early favorable results, mature results of RIC-Allo available in the literature are consistent in demonstrating a lack of long-term disease control.

Autologous stem cell transplantation for refractory or poor-risk relapsed Hodgkin's lymphoma: effect of the specific high-dose chemotherapy regimen on outcome

More active high-dose chemotherapy (HDC) regimens are needed for refractory Hodgkin's lymphoma (HL). We report a cohort analysis of 180 consecutive patients with primary refractory or poor-risk relapsed HL treated with busulfan-melphalan (Bu-Mel) (n = 39), gemcitabine-busulfan-melphalan (Gem-Bu-Mel) (n = 84), or BEAM (BCNU, etoposide, ara-C, melphalan; n = 57) between 2005 and 2010. Their pre-HDC positron emission tomography (PET) scans were interpreted prospectively. Despite more prevalent poor-risk features in the Gem-Bu-Mel cohort, such as PET-positive tumors at HDC, tumors growing at HDC, extranodal disease, or bulky tumors at prior relapse, this cohort had improved outcomes compared with the Bu-Mel and BEAM cohorts, with event-free survival (EFS) rates of 57%, 33%, and 39%, respectively (P = .01), at median follow-up of the whole population of 36 months (range, 3 to 72). Their respective overall survival (OS) rates were, respectively, 82%, 52%, and 59% (P = .04). Secondary acute myelogenous leukemia was seen in 5 patients after BEAM but was not seen in Gem-Bu-Mel and Bu-Mel cohorts (P = .004). Multivariate analyses showed independent adverse effects of an HDC regimen different from Gem-Bu-Mel (hazard ratio [HR] for EFS = 2.3, P = .0008; HR for OS = 2.7, P = .0005), positive PET at HDC (HR for EFS = 2.2, P = .004, HR for OS = 3.1, P = .0001), and >1 previous salvage line (HR for EFS = 1.9, P = .008, HR for OS = 1.8, P = .07). Gem-Bu-Mel improved outcomes in this cohort analysis of patients with refractory/poor-risk relapsed HL and merits evaluation in randomized phase III trials.

Challenges of drug resistance in the management of pancreatic cancer

The current treatment of choice for metastatic pancreatic cancer involves single-agent gemcitabine or a combination of gemcitabine with capecitabine or erlotinib (a tyrosine kinase inhibitor). Only 25&#x2013;30% of patients respond to this treatment and patients who do respond initially ultimately exhibit disease progression. Median survival for pancreatic cancer patients has reached a plateau due to inherent and acquired resistance to these agents. Key molecular factors implicated in this resistance include: deficiencies in drug uptake, alteration of drug targets, activation of DNA repair pathways, resistance to apoptosis and the contribution of the tumor microenvironment. Moreover, for newer agents including tyrosine kinase inhibitors, overexpression of signaling proteins, mutations in kinase domains, activation of alternative pathways, mutations of genes downstream of the target and/or amplification of the target represent key challenges for treatment efficacy. Here we will review the contribution of known mechanisms and markers of resistance to key pancreatic cancer drug treatments.