Plerixafor (P) plus G-CSF (G) in previous peripheral blood progenitor cell (HPC) mobilization failures (MF)

7095

Background: Successful autologous stem cell transplantation (AT) requires harvesting sufficient HPC to ensure reliable engraftment, which cannot be accomplished in ∼10% of previously treated patients. Methods: MF was defined as the inability to collect at least 2 x106 CD34+ cells/kg with growth factor alone (GF) (n=38) or in combination with chemotherapy (GF-CT) (n=27). Of 65 patients reported here, 45 were enrolled in a compassionate use program and 20 were part of a clinical trial (AMD3100–2102); 55 had MM, 9 had lymphoma and 1 had primary amyloidosis. All patients had been treated previously and included prior AT in 26 patients, 15 of whom had 2 AT and 2 had ≥3 AT. The P+G regimen started with G (10 μg/kg) for 4 days, P (240 μg/kg) was added on the evening of day 4; both P and G were continued until completion of collection. In the case of MM, all collected products were analyzed for tumor contamination by DNA/cIg flow cytometry. Results: Of all 65 patients, 63 initiated apheresis which yielded a median 3.6x106 CD34/ kg (range, 0.3–17.8) during a median of 5 days (d) of collection (range, 2–7), with successive median daily CD34 yields of 1.1, 0.9, 0.6, 0.5, 0.3, 0.4 and 0.5 x106/kg. MM cells were mobilized in only 2/55 patients. Additional collection was undertaken in 25 patients, using GF or GF-CT in 19 (median, 3.2x106 CD34 cells; range, 0–8.5), further P+G in 5 (median, 1.7x106 CD34 cells/kg; range, 0.9–3.5), and 1 patient received P+G on a third occasion (2.2x106 CD34 cells /kg). Of 63 patients, 51 (81%) and 24 (38%), respectively, collected ≥2.0 and ≥5.0x106 CD34 /kg. AT was supported with P+G derived products in 43 patients including 7 who received 2 AT. With median infused CD34+cells of 3.6x106 / kg (range, 1.0–7.7), the median times to neutrophils > 500/μl and platelets >20,000/ μl were 14 d (range, 11–35) and 15 d (range, 9–253). Conclusions: P+G ensures collection of an adequate HPC product after MF in 81% that affords durable engraftment even though 40% had prior AT.

[Table: see text]

High CR and near-CR rate with bortezomib incorporated into up-front therapy of multiple myeloma with tandem transplants

7519

Background: Tandem autotransplants have increased complete response (CR) rates and extended event-free survival (EFS) and overall survival (OS) in multiple myeloma (MM). Because of its remarkable efficacy in end-stage disease and to further increase CR and thereby improving EFS and OS, bortezomib (Velcade, V) was incorporated into Total Therapy 3 (TT3), both with DT-PACE combination chemotherapy (dex, thalidomide, cis-platin, adriamycin, cyclophosphamide, etoposide) as induction prior to and consolidation after transplant. Methods: TT3 has accrued 247 of a target population of 300 patients; median follow-up is 16 months. Twenty-seven percent of patients were 65 yr and older; cytogenetic abnormalities (CA) were present in 31% and inter-phase FISH-based deletion 13 in 42%. Results: Median times to 1st and 2nd transplants were 3 mo and 5 mo, with projected completion rates of 95% and 82%. The cumulative frequency of CR plus near-CR was 50% at 6 mo, 75% at 12 mo, reaching 80% at 18 mo. Blood stem cells were readily procured, yielding ≥20 million CD34 cells/kg in > 95%. At 12 mo, 91% are alive and 89% event-free. Relapse has occurred in 29 patients, whose distinguishing features included age ≥ 65 yr (48% vs 24%, p = .005), abnormal cytogenetics (CA, 48% vs. 29%, p = .03) and LDH > ULN (48% vs 23%, p = .004). Among 21 deaths, baseline features were: creatinine >4 mg/dL in 4; age ≥ 65 yr in 11; PS > 3 in 5 and PS > 2 in 4; CRP > 10 mg/L in 9 patients. Conclusions: Introducing V in TT3 as part of combination chemotherapy is safe, permits robust stem cell collection and induces remarkably high CR plus near-CR rates. High-risk MM features such as CA and LDH, defined in Total Therapies 1 and 2, also appeared detrimental with TT3.

[Table: see text]

Phase I, multicenter trial of CNTO 328, an anti-interleukin(IL)-6 monoclonal antibody (mAb) in subjects with selected hematologic malignancies

2513

Background: IL-6 is implicated in the pathophysiology of several malignant diseases, including multiple myeloma (MM) and other hematological malignancies. CNTO 328 is a chimeric monoclonal antibody (mAb) that specifically binds and neutralizes human IL-6 with high affinity. A phase I trial is being conducted to assess safety and pharmacokinetics (PK) of CNTO 328 in subjects with B-cell non-Hodgkin’s lymphoma (NHL), MM, or Castleman’s Disease (CD). Methods: This trial will enroll at least 6 patients (pts) onto each of 5 cohorts, with 3 pts having a baseline C-reactive protein (CRP) of <10 mg/L, and 3 with ≥10 mg/L. Dose limiting toxicity (DLT) is defined as a ≥ Grade 3 event (excluding hematologic toxicity), or ≥Grade 2 allergic reaction/hypersensitivity attributed to CNTO 328 after the first administration. Results: Results from the first 13 subjects (3 CD, 3 MM and 7 NHL) enrolled in Cohorts 1 and 2 are currently available. Pts have received a median number of 4 (range 2 to 12) intravenous doses. CNTO 328 alone was well tolerated without pre-medication, and no DLTs have been observed. Some grade 3 or 4 adverse events (AEs) such as nausea, vomiting, elevated triglycerides, and decreased neutrophils were observed. Two subjects experienced serious AEs (SAEs) that were deemed unrelated to CNTO 328. Each of 3 pts with CD showed a clinical response, including improvement of hemoglobin, reduction of fever, resolution of rash, or decrease in lymphadenopathy. In one case of mantle cell NHL there was a reduction in lymphadenopathy. Two of 4 pts with previously progressive MM showed stabilization of M-protein levels and in % plasma cells in the bone marrow after one cycle of therapy. PK data is being analyzed. Conclusions: Treatment with CNTO 328 has been well tolerated at doses up to 6 mg/kg q 2 weeks. No clinical immune reaction to this chimeric mAb has been observed, and early evidence of tumor response and disease control has been observed.

[Table: see text]

Iron overload is a major risk factor for severe infection after autologous stem cell transplantation: a study of 367 myeloma patients

We evaluated the risk factors for infection of 367 consecutive myeloma patients who underwent high-dose melphalan and autologous stem cell transplantation (ASCT). Examination of bone marrow iron stores (BMIS) prior to ASCT was used to evaluate body iron stores. Other variables included age, sex, active smoking, myeloma remission status, severity of mucositis and duration of severe neutropenia post-ASCT (<100 absolute neutrophils counts (ANC)/microl). Median age was 56 years; 61% of patients were males. 140 episodes of severe infections occurred in 116 patients, including bacteremia (73), pneumonia (40), severe colitis (25) and bacteremia with septic shock (two). The infection incidence per 1,000 days at risk was 45.2. Pre-ASCT risk factors for severe infection by univariate analysis were increased BMIS (OR=2.686; 95% CI 1.707-4.226; P<0.0001), smoking (OR=1.565; 95% CI 1.005-2.437; P=0.0474) and male gender (OR=1.624; 95% CI 1.019-2.589; P=0.0414). Increased BMIS (OR=2.716; 95% CI 1.720-4.287; P<0.0001) and smoking (OR=1.714; 95% CI 1.081-2.718; P=0.022) remained significant by multivariate analysis. Duration of ANC <100 micro/l (OR=1.129; 95% CI 1.039-1.226; P=0.0069 and OR=1.127; 95% CI 1.038-1.224; P=0.0045 by both univariate and multivariate analysis, respectively) was the only post-ASCT risk factor for infection. Increased pre-transplant BMIS and smoking are significant predictors of severe infection after myeloablative chemotherapy followed by ASCT in myeloma patients.

Haploidentical vs autologous hematopoietic stem cell transplantation in patients with acute leukemia beyond first remission

This is a retrospective comparison of partially mismatched related donor transplantation (PMRDT) and autotransplantation (ABMT) in advanced acute leukemia. Patients underwent T-cell-depleted PMRDT (n=164) or ABMT (n=131) for acute myeloid leukemia (n=130) or acute lymphoblastic leukemia (n=165). Fewer PMRDT patients were in remission (29 vs 85%; P<0.0001). The 5-year cumulative incidence of transplant-related mortality (TRM) was 52% after PMRDT and 16% after ABMT (P<0.0001). The 5-year cumulative incidence of relapse was 32% after PMRDT and 54% after ABMT (P=0.006). The actuarial unadjusted 5-year disease-free survival (DFS) was 16% after PMRDT and 30% after ABMT. In Cox's regression analysis, PMRDT (P<0.0001) and age >15 years (P=0.002) were associated with higher TRM, active disease (P=0.0021), ABMT (P=0.0074) and male sex (P=0.011) with higher relapse, and age >15 years (P=0.0007) and PMRDT (P=0.047) with lower DFS. Amongst second remission patients, TRM was higher after PMRDT (P=0.0003), relapse was higher after ABMT (P=0.034), and 5-year DFS was comparable (32% ABMT and 25% PMRDT). ABMT, if feasible, may be preferable to PMRDT in advanced acute leukemia patients since lower relapse after PMRDT is offset by higher TRM. If an autograft is not feasible because of nonavailability of autologous cells or very advanced disease, PMRDT is a potential alternative.

CD4(+) bias in T cells cloned from a CML patient with active graft versus leukemia effect

BACKGROUND

The ability to generate a GvL response by infusion of donor leukocytes (DL) in patients following relapse after BMT is now well documented and has been demonstrated to be particularly effective in patients with CML.

METHODS

We generated T-cell lines from a patient who was undergoing an active GvL response following withdrawal of immunosuppression for cytogenetic relapse of CML. Cryopreserved pre-transplant leukemic cells were used as stimulators, to generate T-cell lines and oligoclonal lines from the lymphocytes. In total 38 sub-lines were generated from different bulk cultures. The lines were tested for their proliferative and cytotoxic capability to patient pre-transplant leukemic cells, PHA-transformed lymphoblasts, allogeneic CML cells, and autologous and allogeneic B-LCL.

RESULTS

Four of the cloned lines tested recognized the patient's pre-transplant leukemic cells. Specifically, two were both cytotoxic and proliferative in response to patient leukemic cells and two were cytotoxic only. Six clonal lines recognized PHA blasts only and were proliferative; one was specific for PHA blasts and CML cells. The sub-lines were phenotyped for cell-surface markers and all were CD4(+) CD8(-) CD 16/56(-). The proliferative response of the leukemia-specific clonal lines could be blocked with anti-MHC Class II MAbs.

DISCUSSION

These data suggest that CD4(+) cells play a crucial role in mediating the GvL effect in CML patients. Our observations can be used to delineate strategies for enhancing and investigating the GvL effect in CML.

Transplantation as salvage therapy for high-risk patients with myeloma in relapse

Patients with myeloma relapsing after tandem transplant have a poor survival and treatment options are limited. The role of additional salvage transplant procedures for these patients is unknown. To evaluate the benefit and identify prognostic factors, the outcome of 76 consecutive patients with recurrent myeloma after tandem transplant receiving salvage transplants (ST) was analyzed. Prior to ST, 23 patients (30%) had shown chemosensitive response to preceding salvage chemotherapy: two complete remissions (CR); eight near CRs (nCR: only immunofixation positive); 13 partial remissions (PR >or=75% reduction in M protein). Fifty received an autologous transplant, 22 a sibling-matched allogeneic transplant, and four a matched-unrelated allogeneic transplant. Overall response after ST was 59%: eight CRs (11%); 14 nCRs (18%); 23 PRs (30%). Overall survival (OS) at 2 years was 19%; 2 year event-free survival rate (EFS) 7%. On univariate analysis for survival, only pre-transplant chemosensitive relapse (P < 0.05), serum albumin >3 g/dl (P = 0.001), normal LDH (P = 0.04), and long interval between the second transplant and relapse/progression were significant beneficial factors. In a Cox proportional hazard model, chemosensitive relapse, and albumin >3 g/dl were significant for better OS: hazard ratio (HR) 1.4, 1.7, respectively, while normal LDH, and absence of CA13 were significant for better EFS: HR 1.8, 1.7, respectively. Patients with albumin >3 g/dl who had chemosensitive disease before ST (n = 16) had a median survival of 16 months, compared to 7 months (n = 34) and 2 months (n = 26) for patients with only one (n = 34) or no favorable prognostic factors (n = 28), respectively (P < 0.001). Their survival at 2 years post-ST was 43%, 17% and 11%, respectively. Our study suggests further transplantation should only be considered in the setting of a clinical trial in patients with favorable prognostic factors.

Separating graft-versus-tumor from graft-versus-host reactions

The full therapeutic potential of allogeneic stem cell transplantation, through its immunologically mediated graft-versus-tumor effect, in patients with hematologic malignancies is greatly compromised by the occurrence of graft-versus-host disease. Unfortunately, the use of non-selective immunosuppressive agents to reduce the incidence and severity of graft-versus-host disease is associated with severe immune compromise of the host and most likely a greater relapse risk of the underlying malignancy. Many attempts have been made to clinically separate these two effects. A critical overview of the published experience is the focus of this report. As the effector cells responsible for the two reactions are largely unknown, the limited success of the various approaches used is not surprising. A more thorough understanding of the antigenic stimuli involved in the initiation of the two reactions and of the molecular pathways through which the cytotoxic effects of T-cells are mediated is essential for abrogating graft-versus-host disease while preserving the graft-versus-tumor effect.

Allogeneic bone marrow transplantation from partially mismatched related donors as therapy for primary induction failure acute myeloid leukemia

The outcome of acute myeloid leukemia patients with primary refractoriness to conventional chemotherapy is extremely poor. Allogeneic bone marrow transplants with matched sibling or matched unrelated donors provide 10-20% disease-free survival in this setting. We analyzed our transplant experience using readily available partially mismatched related donor (PMRD) in patients with primary induction failure (PIF) AML. Between March 1994 and December 1998, 13 patients with PIF AML were transplanted from 0-3 HLA antigen mismatched donors. All 12 evaluable patients engrafted at a median of day +16. Ten (77%) patients survived at least 100 days after transplant. Acute GVHD (grade II) was observed in one of 12 patients. Chronic GVHD was seen in one of 10 patients surviving beyond day 100. The major cause of failure was relapse of disease in six occurring 3-12 months after PMRD BMT. Three patients are alive without disease 14, 36 and 45 months post BMT with Karnofsky scores of 100%. The actuarial 3-year probabilities of relapse and disease-free survival were 0.54 and 0.19, respectively. We concluded that a PMRD graft is a viable option, comparable to the use of matched related or unrelated donors, in patients with PIF AML in whom time is of the essence.

Pharmacologic doses of granulocyte colony-stimulating factor affect cytokine production by lymphocytes in vitro and in vivo

Peripheral blood stem cell (PBSC) transplantation is successful in improving engraftment without increasing acute graft-versus-host disease (GVHD), despite much larger numbers of T cells in unmanipulated PBSCs than in bone marrow grafts. In mouse models and retrospective human studies, granulocyte colony-stimulating factor (G-CSF) therapy has been associated with less acute GVHD. We studied the effect of G-CSF on interferon (IFN)-gamma and IL-4 expression in CD4(+) lymphocytes. CD4(+) cells co-cultivated with G-CSF and stimulated with PHA or CD3 monoclonal antibodies showed significant decreases in IFN-gamma and increases in IL-4 expression (n = 13; P <. 01). G-CSF appeared to have a direct effect on CD4(+) cells independent of monocytes present in the culture because purified CD4(+) cells exposed to G-CSF, washed, and cocultivated with untreated monocytes demonstrated similar changes in IFN-gamma and IL-4 expression, whereas untreated CD4(+) cells cocultured with G-CSF-stimulated monocytes behaved as controls. We then studied peripheral blood mononuclear cells (PBMCs) from G-CSF-mobilized PBSC donors. When their PBMCs were cultured with PHA or CD3 monoclonal antibody, the percent of IFN-gamma-expressing cells decreased by a mean of 55% and 42%, respectively, whereas the percent of IL-4-containing cells increased by a mean of 39% and 58%, respectively, following G-CSF stimulation. Increased apoptosis of IFN-gamma-producing CD4(+) cells was not responsible for the shift in TH1/TH2 subsets. G-CSF-R mRNA was present in both CD4(+) and CD8(+) cells. These results suggest that G-CSF decreases IFN-gamma and increases IL-4 production in vitro and in vivo and likely modulates a balance between TH1 and TH2 cells, an effect that may be important in PBSC transplantation.

High-dose corticosteroid therapy for diffuse alveolar hemorrhage in allogeneic bone marrow stem cell transplant recipients

In a series of 74 patients with hematological malignancies undergoing allogeneic bone marrow or peri- pheral blood stem cell transplants from an HLA-identical sibling donor, four developed diffuse alveolar hemorrhage (DAH) between days 0 and 23 post transplant. Diagnosis was made by the radiographic finding of diffuse bilateral lung opacities, and bloody lavage fluid on bronchoscopy. Two patients required mechanical ventilatory support. They were treated with methylprednisolone 0.25-1.5 g/day for at least 4 days with slow tapering thereafter. All patients showed an immediate response and two became long-term survivors with normal respiratory function. Two had a relapse of DAH, developed acute respiratory distress syndrome (ARDS) and died with multi-organ failure. Risk factors for DAH were one or more courses of intensive chemotherapy pretransplant vs no treatment or low-dose chemotherapy (4/4 DAH vs 23/70 no DAH; P = 0.015), and second transplants (2/2 DAH vs 1/70 with no DAH; P = 0.006). These results indicate that DAH is life-threatening but is potentially reversible by prompt treatment with high doses of steroids.

Polymorphism in CD33 and CD34 genes: a source of minor histocompatibility antigens on haemopoietic progenitor cells?

Following bone marrow stem cell transplantation allo-responses against haemopoietic progenitor cells (HPC), causing graft rejection and graft-versus-leukaemia effects, can be induced by donor T cells recognizing peptides derived from polymorphic endogenous proteins present in HPC. Since CD33 and CD34 are both expressed on HPC, we looked for genetic polymorphisms that might be the source of minor histocompatibility antigens (mHA) on such cells. Bone marrow from 14 donors and their HLA-identical recipients undergoing BMT for haematological malignancies were studied. Using non-radioactive single-strand conformation polymorphism analysis (cold SSCP) of complementary DNA encoding CD33 and CD34, three DNA polymorphisms, two in CD33 and one in CD34 were found and sequenced. Two were in non-coding regions, but in CD33, ATA or ATG at codon 183 resulted in an Ile or Met in the protein sequence. Nonapeptides derived from both alleles were predicted to bind to HLA A68.1. Thus two alleles of CD33 protein exist that could be mHA. With an alternate allele frequency of < 10%, allo-responses against CD33 would be uncommon after marrow transplantation. However, donors homozygous for this allele could be used to generate cytotoxic T cells against the frequent CD33 allele, for adoptive therapy of leukaemia.