Phase 2 clinical trial evaluating abatacept in patients with steroid-refractory chronic graft-versus-host disease.

Steroid-refractory chronic graft-versus-host disease (cGVHD) after allogeneic transplant remains a significant cause of morbidity and mortality. Abatacept is a selective costimulation modulator, used for the treatment of rheumatologic diseases, and was recently the first drug to be approved by the US Food and Drug Administration for the prophylaxis of acute graft-versus-host disease. We conducted a phase 2 study to evaluate the efficacy of abatacept in steroid-refractory cGVHD. The overall response rate was 58%, seen in 21 out of 36 patients, with all responders achieving a partial response. Abatacept was well tolerated with few serious infectious complications. Immune correlative studies showed a decrease in interleukin -1α (IL-1α), IL-21, and tumor necrosis factor α as well as decreased programmed cell death protein 1 expression by CD4+ T cells in all patients after treatment with abatacept, demonstrating the effect of this drug on the immune microenvironment. The results demonstrate that abatacept is a promising therapeutic strategy for the treatment of cGVHD. This trial was registered at www.clinicaltrials.gov as #NCT01954979.

High CD34-positive cell dose in matched unrelated donor allogeneic hematopoietic stem cell transplant is not associated with graft-versus-host disease or mortality.

BACKGROUND: CD34+ stem cells serve as the primary graft source for allogeneic transplants, with a minimum of 2-4 × 106 cells/kg needed for engraftment. There are conflicting data on outcomes at high stem cell doses, with studies limited by few patients receiving doses far above the minimum target. STUDY DESIGN AND METHODS: In this retrospective, single-center study of patients with hematologic malignancies who underwent matched unrelated donor transplants, we assessed outcomes for engraftment, survival, relapse, and graft-versus-host disease (GVHD) for the highest CD34+ dose quintile (>13 × 106 cells/kg, n = 36) compared to the remaining patients (n = 139). Similar analysis was performed correlating T cell dose and outcomes. RESULTS: There was no difference between the groups in neutrophil engraftment, with a trend toward faster platelet engraftment. There was no significant difference in mortality (adjusted risk ratio [aRR] = 1.02, 95% confidence interval [CI] = 0.85-1.22), relapse (aRR = 1.10, 95% CI = 0.85-1.42), or overall survival by Kaplan-Meier analysis (p = .44). High CD34+ dose was not associated with higher incidence of acute GVHD (aRR = 0.99 grades II-IV, aRR = 1.18 grades III-IV) or chronic GVHD (aRR = 0.87 overall, RR = 1.21 severe). There was limited correlation between CD34+ and T cell dose (R2 = .073), and there was no significant difference in survival, relapse, or GVHD in the highest T cell dose quintile (n = 33) compared to the remaining quintiles (n = 132). DISCUSSION: We found no difference in survival, relapse, or GVHD incidence or severity in patients receiving CD34+ doses above prior cutoffs reported in the literature. These data do not support the routine use of graft CD34+ dose reduction.

Complete responses to odronextamab in two patients with diffuse large B-cell lymphoma refractory to chimeric antigen receptor T-cell therapy.

Outcomes remain poor for patients with relapsed/refractory B-cell non-Hodgkin lymphoma (R/R B-NHL). While chimeric antigen receptor (CAR) T-cell therapy has revolutionised treatment, a significant proportion of patients relapse or fail to respond. Odronextamab is a CD20 × CD3 bispecific antibody that has demonstrated durable responses and a manageable safety profile in patients with R/R B-NHL in a first-in-human trial (NCT02290951). Here, we document two patients with diffuse large B-cell lymphoma refractory to CART-cell therapy. Both achieved complete responses that remain ongoing for ≥2 years following odronextamab. Neither patient experienced Grade ≥3 cytokine release syndrome or Grade ≥3 neurological adverse events during treatment.

Brentuximab vedotin, doxorubicin, vinblastine, and dacarbazine for nonbulky limited-stage classical Hodgkin lymphoma.

Doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) with or without radiation is standard therapy for limited-stage Hodgkin lymphoma (HL) but carries risks of bleomycin-induced lung injury and radiation toxicity. Brentuximab vedotin is highly active in relapsed HL and was recently approved with doxorubicin, vinblastine, and dacarbazine (AVD) for previously untreated stage III/IV HL. We evaluated brentuximab-AVD for nonbulky stage I/II HL in a multicenter phase 2 study. Patients received a lead-in cycle of brentuximab vedotin monotherapy on days 1 and 15, followed by an exploratory positron emission tomography/computed tomography scan. Patients then received brentuximab-AVD for 4 to 6 cycles based on interim positron emission tomography/computed tomography scanning after cycle 2. Thirty-four patients were enrolled with a median age of 36 years (range, 20-75 years). Risk was early favorable in 62% and unfavorable in 38%. The best complete response rate was 100%. At a median follow-up of 38 months, the progression-free survival and overall survival were 94% and 97%, respectively. The most common adverse events were peripheral sensory neuropathy (79%), neutropenia (76%), fatigue (74%), and nausea (71%). The most common grade 3/4 toxicities were neutropenia (62%), febrile neutropenia (35%), and peripheral sensory neuropathy (24%). One elderly patient died of neutropenic sepsis in the first brentuximab-AVD cycle. Brentuximab dose reductions were required in 38% of patients, most for peripheral neuropathy. In conclusion, brentuximab-AVD without bleomycin or radiation produced a high complete response rate, with most patients requiring only 4 total cycles of therapy. Because toxicity was higher than would be expected from AVD alone, this method may not be appropriate for early-stage patients with a highly favorable prognosis. This trial was registered at www.clinicaltrials.gov as #NCT01534078.

PD-1 blockade with pembrolizumab for classical Hodgkin lymphoma after autologous stem cell transplantation.

Autologous stem cell transplantation (ASCT) remains the standard of care for patients with relapsed/refractory (RR) classical Hodgkin lymphoma (cHL) who respond to salvage chemotherapy. However, relapse after ASCT remains a frequent cause of treatment failure, with poor subsequent prognosis. Because cHL is uniquely vulnerable to programmed cell death-1 (PD-1) blockade, PD-1 blockade given as consolidation after ASCT could improve ASCT outcomes. We therefore conducted a multicohort phase 2 study of pembrolizumab in patients with RR cHL after ASCT, hypothesizing that it would improve the progression-free survival (PFS) at 18 months after ASCT (primary end point) from 60% to 80%. Pembrolizumab was administered at 200 mg IV every 3 weeks for up to 8 cycles, starting within 21 days of post-ASCT discharge. Thirty patients were treated on this study. The median age was 33 years, and 90% were high-risk by clinical criteria. Seventy-seven percent completed all 8 cycles. Toxicity was manageable, with 30% of patients experiencing at least 1 grade 3 or higher adverse event (AE), and 40% at least 1 grade 2 or higher immune-related AE. Two patients were lost to follow-up in complete remission at 12 months. The PFS at 18 months for the 28 evaluable patients was 82%, meeting the primary end point. The 18-month overall survival was 100%. In conclusion, pembrolizumab was successfully administered as post-ASCT consolidation in patients with RR cHL, and resulted in a promising PFS in a high-risk patient cohort, supporting the testing of this strategy in a randomized trial. This trial was registered at www.clinicaltrials.gov as #NCT02362997.

Phase 1 clinical trial evaluating abatacept in patients with steroid-refractory chronic graft-versus-host disease.

Steroid-refractory chronic graft-versus-host disease (SR-cGVHD) remains a major cause of morbidity and mortality after allogeneic stem cell transplantation. Innovative immunotherapeutic strategies are urgently needed for the treatment of SR-cGVHD. We conducted a phase 1 clinical trial to evaluate the safety, efficacy, and immune effects of abatacept, a novel immunomodulatory drug that acts as an inhibitor of T-cell activation via costimulatory blockade, in the treatment of SR-cGVHD. The study followed a 3+3 design with 2 escalating abatacept doses: 3 mg/kg and 10 mg/kg, with an expansion cohort treated at 10 mg/kg. Abatacept was well-tolerated with no dose-limiting toxicities. Of the 16 evaluable patients, 44% achieved a clinical partial response per 2005 National Institutes of Health Consensus Criteria. Importantly, abatacept resulted in a 51.3% reduction in prednisone usage in clinical responders (mean baseline, 27 vs 14 mg; P = .01). Increased PD-1 expression on circulating CD4 (P = .009) and CD8 (P = .007) T cells was observed in clinical responders. In summary, abatacept was safe and led to a marked improvement in National Institutes of Health cGVHD scores and a significant reduction in prednisone use. In this cohort of heavily pretreated patients, the results suggest abatacept may be a promising therapeutic agent for SR-cGVHD, and a phase 2 trial has been initiated. This trial was registered at www.clinicaltrials.gov as #NCT01954979.

MUC1-mediated induction of myeloid-derived suppressor cells in patients with acute myeloid leukemia.

Myeloid-derived suppressor cells (MDSCs) play a critical role in promoting immune tolerance and disease growth. The mechanism by which tumor cells evoke the expansion of MDSCs in acute myeloid leukemia (AML) has not been well described. We have demonstrated that patients with AML exhibit increased presence of MDSCs in their peripheral blood, in comparison with normal controls. Cytogenetic studies demonstrated that MDSCs in patients with AML may be derived from leukemic or apparently normal progenitors. Engraftment of C57BL/6 mice with TIB-49 AML led to an expansion of CD11b+ Gr1+ MDSCs in bone marrow and spleen. Coculture of the AML cell lines MOLM-4, THP-1 or primary AML cells with donor peripheral blood mononuclear cells elicited a cell contact-dependent expansion of MDSCs. MDSCs were suppressive of autologous T-cell responses as evidenced by reduced T-cell proliferation and a switch from a Th1 to a Th2 phenotype. We hypothesized that the expansion of MDSCs in AML is accomplished by tumor-derived extracellular vesicles (EVs). Using tracking studies, we demonstrated that AML EVs are taken-up myeloid progenitor cells, resulting in the selective proliferation of MDSCs in comparison with functionally competent antigen-presenting cells. The MUC1 oncoprotein was subsequently identified as the critical driver of EV-mediated MDSC expansion. MUC1 induces increased expression of c-myc in EVs that induces proliferation in the target MDSC population via downstream effects on cell cycle proteins. Moreover, we demonstrate that the microRNA miR34a acts as the regulatory mechanism by which MUC1 drives c-myc expression in AML cells and EVs.

Cabozantinib is well tolerated in acute myeloid leukemia and effectively inhibits the resistance-conferring FLT3/tyrosine kinase domain/F691 mutation.

BACKGROUND: Cabozantinib, a tyrosine kinase inhibitor of FMS-like tyrosine kinase 3 (FLT3), MET, AXL, vascular endothelial growth factor receptor, and KIT, is approved for use in multiple malignancies. We assessed the safety and tolerability of cabozantinib in AML, given up-regulation of multiple relevant pathways. METHODS: Adults were eligible if they were 18 years old or older with relapsed/refractory AML or if they were 70 years old or older with newly diagnosed AML but were ineligible for conventional therapy. Cabozantinib was administered in 28-day cycles, and dose escalation occurred via cohorts. A pharmacodynamic evaluation of serial plasma samples via a plasma inhibitory assay (PIA) was used to assess FLT3-inhibitory activity in FLT3-mutant cell lines. RESULTS: Among 18 patients enrolled, 5 were found to harbor FLT3/ITD mutations. Sixteen patients (89%) had relapsed/refractory AML, and most were treated with 2 or more lines of prior treatment. No dose-limiting toxicities (DLTs) were detected at the first dose level (40 mg daily), but 2 patients experienced DLTs at the next level (60 mg daily). The remaining patients were then dosed at 40 mg daily, the maximum tolerated dose (MTD). Additional grade 2 or higher toxicities, possibly/probably related to cabozantinib, included fatigue, nausea, transaminitis, and electrolyte imbalance. No patients had a marrow response according to formal criteria, but 4 had peripheral blast reductions; 2 of these 4 patients transiently cleared circulating blasts. One patient experienced a reduction in marrow blasts, and 1 had stable disease. The FLT3-inhibitory activity of plasma samples, as assessed with the PIA, revealed potent and sustained inhibition in FLT3/ITD and, notably, F691 tyrosine kinase domain (TKD)-mutant cells. CONCLUSIONS: Cabozantinib is well tolerated in AML patients at an MTD of 40 mg daily and is a potent inhibitor of FLT3/ITD- and F691 TKD-altered tyrosine kinases. Cancer 2018;124:306-14. © 2017 American Cancer Society.

Long-term outcomes, secondary malignancies and stem cell collection following bendamustine in patients with previously treated non-Hodgkin lymphoma.

Despite the long history of bendamustine as treatment for indolent non-Hodgkin lymphoma, long-term efficacy and toxicity data are minimal. We reviewed long-term data from three clinical trials to characterize the toxicity and efficacy of patients receiving bendamustine. Data were available for 149 subjects at 21 sites. The median age was 60 years at the start of bendamustine (range 39-84), and patients had received a median of 3 prior therapies. The histologies included grades 1-2 follicular lymphoma (FL; n = 73), grade 3 FL (n = 23), small lymphocytic lymphoma (n = 20), marginal zone lymphoma (n = 15), mantle cell lymphoma (n = 9), transformed lymphomas (n = 5), lymphoplasmacytic lymphoma (n = 2) and not reported (n = 2). The median event-free survival was 14·1 months. Nine of 12 attempted stem cell collections were successful. With a median follow-up of 8·9 years, 23 patients developed 25 cancers, including 8 patients with myelodysplastic syndrome/acute myeloid leukaemia. These data provide important information regarding the long-term toxicity of bendamustine in previously treated patients. A small but meaningful number of patients achieved durable remissions following bendamustine. These rigorously collected, patient-level, long-term follow-up data provide reassurance that bendamustine or bendamustine plus rituximab is associated with efficacy and safety for patients with relapsed or refractory indolent non-Hodgkin lymphoma.

Mucin 1 is a potential therapeutic target in cutaneous T-cell lymphoma.

Cutaneous T-cell lymphoma (CTCL) is an aggressive neoplasm with limited treatments for patients with advanced disease. The mucin 1 C-terminal subunit (MUC1-C) oncoprotein plays a critical role in regulating cell proliferation, apoptosis, and protection from cytotoxic injury mediated by reactive oxygen species (ROS). Although CTCL cells exhibit resistance to ROS-induced apoptosis, the expression and functional significance of MUC1 in CTCL have not been previously investigated. Present studies demonstrate that MUC1-C is overexpressed in CTCL cell lines and primary CTCL cells but is absent in resting T cells from healthy donors and B-cell lymphoma cells. We have developed a cell-penetrating peptide that disrupts homodimerization of the MUC1-C subunit necessary for its nuclear translocation and downstream signaling. We show that treatment of CTCL cells with the MUC1-C inhibitor is associated with downregulation of the p53-inducible regulator of glycolysis and apoptosis and decreases in reduced NAD phosphate and glutathione levels. In concert with these results, targeting MUC1-C in CTCL cells increased ROS and, in turn, induced ROS-mediated late apoptosis/necrosis. Targeting MUC1-C in CTCL tumor xenograft models demonstrated significant decreases in disease burden. These findings indicate that MUC1-C maintains redox balance in CTCL cells and is thereby a novel target for the treatment of patients with CTCL.

A phase 2 study of Rituximab-Bendamustine and Rituximab-Cytarabine for transplant-eligible patients with mantle cell lymphoma.

Chemoimmunotherapy followed by autologous stem cell transplantation (ASCT) is a standard therapy for transplant-eligible patients with newly diagnosed mantle cell lymphoma (MCL). The achievement of complete remission (CR) and minimal residual disease (MRD) negativity are associated with better outcomes. We tested an induction regimen of rituximab/bendamustine followed by rituximab/high-dose cytarabine (RB/RC). This phase 2 study (NCT01661881) enrolled 23 transplant-eligible patients aged 42-69, of whom 70% were MCL international prognostic index low-risk. Patients received three cycles of RB followed by three cycles of RC. The primary endpoint of the trial was the rate of CR after six cycles of therapy, with a rate of 75% considered promising. 96% of patients achieved a CR/unconfirmed CR after treatment, meeting the primary objective. One patient progressed on study, one declined ASCT in CR, and the remaining 21 underwent successful stem cell collection and ASCT. After a median follow-up of 13 months, the progression-free survival rate was 96%. Among 15 MRD-evaluable patients who completed treatment, 93% achieved MRD negativity after RB/RC. In conclusion, RB/RC achieves very high CR and MRD negativity rates in transplant-eligible patients, with a favourable safety profile. RB/RC warrants further comparative studies, and may become a useful alternative to RCHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone)-based induction regimens in this patient population.

Ofatumumab in combination with ICE or DHAP chemotherapy in relapsed or refractory intermediate grade B-cell lymphoma.

Standard treatment of transplant-eligible patients with relapsed diffuse large B-cell lymphoma (DLBCL) consists of rituximab and platinum-based chemotherapy, either ifosfamide, carboplatin, and etoposide (ICE) or dexamethasone, cytarabine, and cisplatin (DHAP), with autologous transplant consolidation for those with chemosensitive disease. Nonetheless, outcomes are suboptimal for patients failing rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP). We performed a multi-center phase II trial investigating the safety and efficacy of ofatumumab, a monoclonal antibody against CD20, combined with ICE or DHAP second-line therapy in patients with relapsed or refractory DLBCL, grade 3b follicular lymphoma, or transformed follicular lymphoma. Sixty-one patients were treated with either ofatumumab-ICE (35) or ofatumumab-DHAP (26). The overall response rate (ORR) was 61%, and the complete response (CR) rate was 37%. In patients with 2 or 3 adverse risk factors according to the second-line, age-adjusted, international prognostic index, the ORR was 59% and CR 31%, and in patients with early-relapsing or primary refractory disease, the ORR was 55% and CR 30%. Toxicity was largely hematologic, and stem cell mobilization was successful in 43 of 45 patients. Substitution of ofatumumab for rituximab in standard second-line regimens following failure of R-CHOP is a promising approach. This trial was registered at www.clinicaltrials.gov as NCT00823719.

Yttrium-90 ibritumomab tiuxetan followed by rituximab maintenance as treatment for patients with diffuse large B-cell lymphoma are not candidates for autologous stem cell transplant.

BACKGROUND: Not all patients with diffuse large B-cell lymphoma (DLBCL) are candidates for aggressive regimens. (90)Y ibritumomab tiuxetan ((90)Y-IT), an anti-CD20 radionuclide-conjugated antibody, has demonstrated clinical efficacy in DLBCL with a favorable toxicity profile. METHODS: This phase II trial investigated the overall response rate (ORR), event-free survival (EFS), overall survival (OS) and toxicity of treatment with (90)Y-IT (0.4 or 0.3 mCi (90)Y/kg based on platelets) followed by rituximab maintenance therapy in patients with DLBCL not candidates for transplant. RESULTS: 25 patients were enrolled. At best response 8 patients obtained a complete response (CR) and 1 a partial response (ORR 36%). Median EFS was 2.5 months and OS 8.1 months. No patient who obtained CR later relapsed systemically. Two patients were free of disease at the 61- and 100-month follow-ups; 65% had grade 3/4 thrombocytopenia, but no significant bleeding was observed. Grade 3 nonhematologic toxicity occurred in 36%. Patients who had progressed through a rituximab-containing regimen responded poorly. CONCLUSION: The ORR of 36% with (90)Y-IT as salvage therapy for DLBCL while inferior to more aggressive regimens is significant with acceptable toxicity. For a subset of patients not candidates for salvage with autologous transplant, this treatment strategy can produce a durable, long-lasting remission.

Interleukin-2 and regulatory T cells in graft-versus-host disease.

BACKGROUND: Dysfunction of regulatory T (Treg) cells has been detected in diverse inflammatory disorders, including chronic graft-versus-host disease (GVHD). Interleukin-2 is critical for Treg cell growth, survival, and activity. We hypothesized that low-dose interleukin-2 could preferentially enhance Treg cells in vivo and suppress clinical manifestations of chronic GVHD. METHODS: In this observational cohort study, patients with chronic GVHD that was refractory to glucocorticoid therapy received daily low-dose subcutaneous interleukin-2 (0.3×10(6), 1×10(6), or 3×10(6) IU per square meter of body-surface area) for 8 weeks. The end points were safety and clinical and immunologic response. After a 4-week hiatus, patients with a response could receive interleukin-2 for an extended period. RESULTS: A total of 29 patients were enrolled. None had progression of chronic GVHD or relapse of a hematologic cancer. The maximum tolerated dose of interleukin-2 was 1×10(6) IU per square meter. The highest dose level induced unacceptable constitutional symptoms. Of the 23 patients who could be evaluated for response, 12 had major responses involving multiple sites. The numbers of CD4+ Treg cells were preferentially increased in all patients, with a peak median value, at 4 weeks, that was more than eight times the baseline value (P<0.001), without affecting CD4+ conventional T (Tcon) cells. The Treg:Tcon ratio increased to a median of more than five times the baseline value (P<0.001). The Treg cell count and Treg:Tcon ratio remained elevated at 8 weeks (P<0.001 for both comparisons with baseline values), then declined when the patients were not receiving interleukin-2. The increased numbers of Treg cells expressed the transcription factor forkhead box P3 (FOXP3) and could inhibit autologous Tcon cells. Immunologic and clinical responses were sustained in patients who received interleukin-2 for an extended period, permitting the glucocorticoid dose to be tapered by a mean of 60% (range, 25 to 100). CONCLUSIONS: Daily low-dose interleukin-2 was safely administered in patients with active chronic GVHD that was refractory to glucocorticoid therapy. Administration was associated with preferential, sustained Treg cell expansion in vivo and amelioration of the manifestations of chronic GVHD in a substantial proportion of patients. (Funded by a Dana-Farber Dunkin' Donuts Rising Star award and others; ClinicalTrials.gov number, NCT00529035.).

Sequential infusion of donor-derived dendritic cells with donor lymphocyte infusion for relapsed hematologic cancers after allogeneic hematopoietic stem cell transplantation.

Donor lymphocyte infusion (DLI) is often given to induce a graft-versus-leukemia (GVL) effect after allogeneic hematopoietic stem cell transplantation (HSCT). However, efficacy of DLI is limited in most hematologic cancers. As antigen presenting cells, dendritic cells (DC) bolster immune responses. We conducted a Phase I trial testing the coinfusion of DC followed by DLI. DC were generated by culturing peripheral blood mononuclear cells from HLA matched-related donors in GM-CSF and IL-4 for 7 days, followed by TNF-α for 3 days. DC were administered intravenously on 3 dose levels (5 × 10(6) ; 1 × 10(7) ; 5 × 10(7) cells). DLI (3 × 10(7) CD3+ cells/kg) was administered intravenously 1 day after the DC. Sixteen patients with hematologic cancers relapsed after HSCT were treated. A maximum tolerated dose for DC was not reached. Two of 16 patients met criteria for DLT within 10 weeks of the infusion: 1 idiopathic respiratory failure, 1 ventricular cardiac arrest. None developed grade III/IV GVHD. One patient developed grade II acute intestinal graft-vs.-host disease (GVHD) and 1 chronic GVHD within 6 months of the infusion. Both resolved with corticosteroids. Four of 14 patients evaluable for disease response achieved durable remissions and are alive and cancer free 6.7, 8.4, 8.8, and 10.1 years from infusion. Sequential infusion of donor-derived DC with DLI is feasible in patients with relapsed hematologic cancers after allogeneic HSCT. Future studies may consider donor DC preloaded with tumor antigens to investigate whether DC infusion could augment the GVL effect.

Successful treatment of refractory Guillain-Barré syndrome with alemtuzumab in a patient with chronic lymphocytic leukemia.

This is the case of a 79-year-old man with chronic lymphocytic leukemia who presented with Guillain-Barré syndrome with features overlapping with the Miller Fisher syndrome and Bickerstaff brainstem encephalitis and positive antiganglioside GQ1b antibody about 6 months after treatment with bendamustine and rituximab. His clinical and neurologic condition continued to deteriorate despite sequential treatment with corticosteroids, intravenous immunoglobulin and plasmapheresis, but in the end, he had a complete and durable response to treatment with alemtuzumab.

Pancreatic atrophy in patients with chronic graft-versus-host disease.

PURPOSE: To determine if patients with chronic graft-versus-host disease (cGVHD) following allogeneic hematopoietic stem cell transplantation (HSCT) develop greater loss of pancreatic tissue than patients without cGVHD. MATERIALS AND METHODS: This is an IRB-approved, HIPAA-compliant retrospective study of patients receiving allogeneic HSCT at our institution from 01/2006 to 01/2010 with abdominal CT performed within 3 months prior to HSCT and CT performed at least 3 months after HSCT. Measurement of glandular tissue thickness of the head, body, and tail of the pancreas was performed independently by two radiologists blinded to clinical data. Statistical analysis was performed using the Student t-test, and interobserver agreement was evaluated with linear-weighted kappa. RESULTS: 117 patients underwent HSCT during study period, with 36 patients meeting inclusion criteria. 22 subjects (61%) had clinical features of cGVHD, and 14 patients (39%) did not have evidence of cGVHD. Following HSCT, there was a significant decrease in mean total thickness (10.9%, p = 0.002) of the pancreas in the group of patients with cGVHD. The change from pretreatment to the nadir in pancreatic thickness was significantly greater in patient with cGVHD (13.9 ± 12.1 mm), but not in non-cGVHD patients (5.4 ± 4.7 mm) (p = 0.02), with head of the pancreas atrophy accounting for the difference (decrease of 4.8 ± 4.6 mm in cGVHD patients vs. 1.6 ± 2.1 mm in non-cGVHD patients (p = 0.02)). CONCLUSION: Patients with cGVHD develop significantly greater loss of pancreatic glandular tissue than patients without cGVHD following HSCT, with atrophy of pancreatic head being a major contributor.

Lenalidomide enhances anti-myeloma cellular immunity.

Lenalidomide is an effective therapeutic agent for multiple myeloma that exhibits immunomodulatory properties including the activation of T and NK cells. The use of lenalidomide to reverse tumor-mediated immune suppression and amplify myeloma-specific immunity is currently being explored. In the present study, we examined the effect of lenalidomide on T-cell activation and its ability to amplify responses to a dendritic cell-based myeloma vaccine. We demonstrate that exposure to lenalidomide in the context of T-cell expansion with direct ligation of CD3/CD28 complex results in polarization toward a Th1 phenotype characterized by increased IFN-γ, but not IL-10 expression. In vitro exposure to lenalidomide resulted in decreased levels of regulatory T cells and a decrease in T-cell expression of the inhibitory marker, PD-1. Lenalidomide also enhanced T-cell proliferative responses to allogeneic DCs. Most significantly, lenalidomide treatment potentiated responses to the dendritic cell/myeloma fusion vaccine, which were characterized by increased production of inflammatory cytokines and increased cytotoxic lymphocyte-mediated lysis of autologous myeloma targets. These findings indicate that lenalidomide enhances the immunologic milieu in patients with myeloma by promoting T-cell proliferation and suppressing inhibitory factors, and thereby augmenting responses to a myeloma-specific tumor vaccine.

Vaccination with dendritic cell/tumor fusion cells results in cellular and humoral antitumor immune responses in patients with multiple myeloma.

We have developed a tumor vaccine in which patient-derived myeloma cells are chemically fused with autologous dendritic cells (DCs) such that a broad spectrum of myeloma-associated antigens are presented in the context of DC-mediated costimulation. We have completed a phase 1 study in which patients with multiple myeloma underwent serial vaccination with the DC/multiple myeloma fusions in conjunction with granulocyte-macrophage colony-stimulating factor. DCs were generated from adherent mononuclear cells cultured with granulocyte-macrophage colony-stimulating factor, interleukin-4, and tumor necrosis factor-α and fused with myeloma cells obtained from marrow aspirates. Vaccine generation was successful in 17 of 18 patients. Successive cohorts were treated with 1 × 10(6), 2 × 10(6), and 4 × 10(6) fusion cells, respectively, with 10 patients treated at the highest dose level. Vaccination was well tolerated, without evidence of dose-limiting toxicity. Vaccination resulted in the expansion of circulating CD4 and CD8 lymphocytes reactive with autologous myeloma cells in 11 of 15 evaluable patients. Humoral responses were documented by SEREX (Serologic Analysis of Recombinant cDNA Expression Libraries) analysis. A majority of patients with advanced disease demonstrated disease stabilization, with 3 patients showing ongoing stable disease at 12, 25, and 41 months, respectively. Vaccination with DC/multiple myeloma fusions was feasible and well tolerated and resulted in antitumor immune responses and disease stabilization in a majority of patients.