Current status and future perspectives for yttrium-90 ((90)Y)-ibritumomab tiuxetan in stem cell transplantation for non-Hodgkin's lymphoma

Haematopoietic SCT is currently considered a therapeutic option mainly in relapsed or refractory non-Hodgkin's lymphoma (NHL) owing to high post-transplantation relapse rates and significant toxicity of conventional myeloablative conditioning for allogeneic SCT. Radiolabelled immunotherapy combines the benefits of monoclonal antibody targeting with therapeutic doses of radiation, and is a promising advance in the treatment of malignant lymphomas. It is now under investigation as a component of conditioning prior to SCT, with the aim of improving outcomes following SCT without increasing the toxicity of high-dose chemotherapy pre-transplant conditioning. An expert panel met at a European workshop in November 2006 to review the latest data on radiolabelled immunotherapy in the transplant setting, and its potential future directions, with a focus on (90)Y-ibritumomab tiuxetan. They reviewed data on the combination of standard/high/escalating dose (90)Y-ibritumomab tiuxetan with high-dose chemotherapy, and high/escalating dose (90)Y-ibritumomab tiuxetan as the sole myeloablative agent, prior to autologous SCT, and also (90)Y-ibritumomab tiuxetan as a component of reduced intensity conditioning prior to allogeneic SCT. The preliminary data are highly promising in terms of conditioning tolerability and patient outcomes following transplant; further phase II studies are now needed to consolidate these data and to investigate specific patient populations and NHL subtypes.     

Efficacy and safety of yttrium-90 ibritumomab tiuxetan in patients with relapsed or refractory diffuse large B-cell lymphoma not appropriate for autologous stem-cell transplantation

A prospective, multicenter, nonrandomized phase 2 trial was conducted to evaluate the efficacy and safety of a single dose of yttrium-90 ((90)Y) ibritumomab tiuxetan in elderly patients in first relapsed or primary refractory diffuse large B-cell lymphoma (DLBCL) ineligible for stem-cell transplantation. Patients had been previously treated with chemotherapy (group A, n = 76) or chemotherapy plus rituximab (group B, n = 28). Patients in group A were further divided into patients in whom induction therapy had failed (stratum AI, n = 33) and patients who had relapsed after achieving complete response (CR; stratum AII, n = 43). The overall response rate (ORR) was 52% and 53% in strata AI and AII, respectively, and 19% in group B, with CR/CRu rates of 24%, 39.5%, and 12%, respectively. Median progression-free survival was 5.9 months and 3.5 months in strata AI and AII, respectively, and 1.6 months in group B. Median overall survival was 21.4, 22.4, and 4.6 months in stratum AI, stratum AII, and group B, respectively. Two patients died from thrombocytopenic cerebral bleeding following administration of therapy. Nonhematologic adverse events were mild to moderate. (90)Y-ibritumomab is active in patients with relapsed and refractory diffuse large B-cell lymphoma (DLBCL) and its further evaluation in phase 3 studies is ongoing.     

Treatment of relapsed or refractory Hodgkin disease and non-Hodgkin lymphoma with high-dose chemoradiotherapy followed by unstimulated autologous peripheral stem cell rescue.

Nine patients with relapsed or refractory Hodgkin disease or non-Hodgkin lymphoma underwent peripheral stem cell autografting because of a history of marrow involvement with visible lymphoma. Peripheral stem cells were collected during a process of unstimulated leukapheresis. Recovery to a neutrophil count of 0.1 x 10(9)/L was seen at a median of 14 days compared with a median of 18 days for a concurrent series of marrow recipients (P = .12). Recoveries to a neutrophil count of 0.5 x 10(9)/L and a platelet count of 50 x 10(9)/L occurred at medians of 25 days and 28 days, respectively. These figures are not significantly different from those obtained in the marrow recipients. Of the original nine patients, six are surviving free of disease progression or relapse at a median of 240 days posttransplant. Two patients died of transplant-related complications and one relapsed 250 days post-transplant. All surviving patients remain independent of transfusions and six have attained almost complete hematological reconstitution. Although administration of cytotoxic therapy and granulocyte-macrophage colony-stimulating factor (GM-CSF) may enhance the yield of early progenitor cells during leukapheresis, unstimulated leukapheresis results in a stem cell product capable of rapidly restoring and sustaining marrow function even after multiple courses of intensive "salvage" therapy. Additional follow-up will be needed to determine whether preliminary survival figures continue to compare favorably with those of patients with similar extramedullary disease states undergoing marrow transplants.     

High-dose cyclophosphamide, carmustine, and etoposide followed by autologous peripheral stem cell transplantation for patients with relapsed Hodgkin's disease.

Between February 1986 and March 1990, 56 patients with relapsed Hodgkin's disease treated with high-dose cyclophosphamide, carmustine, and etoposide (CBV) received an autologous peripheral stem cell transplantation (PSCT) rather than an autologous bone marrow transplantation (ABMT) because each patient had a marrow abnormality, either hypocellularity or tumor involvement. At least 6.5 x 10(8) [corrected] mononuclear cells/kg patient weight were collected from the peripheral blood of each patient, cyropreserved, and returned intravenously following CBV administration. Three patients had an early death 2, 22, and 25 days after PSCT. The actuarial event-free survival for these 56 patients at 3 years was 37% and was at least as good as that reported for relapsed Hodgkin's disease patients treated with CBV and ABMT. The 30 patients who had no marrow metastases at the time of PSC harvesting had an actuarial event-free survival of 47%, while those 26 patients with marrow metastases had a significantly different actuarial event-free survival of 27% (P = .02). CBV and PSCT for patients with relapsed Hodgkin's diseases who have marrow hypocellularity in traditional harvest sites or histopathologic evidence of BM metastases can result in long-term event-free survival.     

A phase II trial evaluating the efficacy of high-dose Radioiodinated Tositumomab (Anti-CD20) antibody,etoposide and cyclophosphamide followed by autologous transplantation,for high-risk relapsed or refractory non-hodgkin lymphoma

Radiation is the most effective treatment for localized lymphoma, but treatment of multifocal disease is limited by toxicity. Radioimmunotherapy (RIT) delivers tumoricidal radiation to multifocal sites, further augmenting response by dose-escalation. This phase II trial evaluated high-dose RIT and chemotherapy prior to autologous stem-cell transplant (ASCT) for high-risk, relapsed or refractory (R/R) B-cell non-Hodgkin lymphoma (NHL). The primary endpoint was progression free survival (PFS). Secondary endpoints were overall survival (OS), toxicity, and tolerability. Patients age < 60 years with R/R NHL expressing CD20 were eligible. Mantle cell lymphoma (MCL) patients could proceed to transplant in first remission. Patients received I-131-tositumomab delivered at ≤25Gy to critical normal organs, followed by etoposide, cyclophosphamide and ASCT. A group of 107 patients were treated including aggressive lymphoma (N = 29), indolent lymphoma (N = 45), and MCL (N = 33). After a median follow-up of 10.1 years, the 10-year PFS for the aggressive, indolent, and MCL groups were 62%, 64%, 43% respectively. The 10-year OS for the aggressive, indolent, and MCL groups were 61%, 71%, 48% respectively. Toxicities were similar to standard conditioning regimens and non-relapse mortality at 100 days was 2.8%. Late myeloid malignancies were seen in 6% of patients. High-dose I-131-tositumomab, etoposide and cyclophosphamide followed by ASCT appeared feasible, safe, and effective in treating NHL, with estimated PFS at 10-years of 43%-64%. In light of novel cellular therapies for R/R NHL, high-dose RIT-containing regimens yield comparable efficacy and safety and could be prospectively compared.     

Ifosfamide, etoposide, cytarabine, and dexamethasone as salvage treatment followed by high-dose cyclophosphamide, melphalan, and etoposide with autologous peripheral blood stem cell transplantation for relapsed or refractory lymphomas

High-dose chemotherapy (HD-CT) with autologous stem cell transplantation is considered to be the treatment of choice for relapsed high-grade non-Hodgkin's lymphoma (NHL) and Hodgkin's lymphoma (HL) patients, but the optimal treatment has not yet been defined. We evaluated a salvage treatment regimen consisting of conventional cycles with ifosfamide, etoposide, cytarabine, and dexamethasone (IVAD) followed by two cycles of HD-CT consisting of cyclophosphamide, melphalan, and etoposide (CMV) with autologous stem cell support in patients with relapsed or refractory NHL (n = 59) and HL (n = 16). Response to IVAD was complete remission (CR) in 16 patients (21%), partial remission (PR) in 39 patients (52%), stable disease (SD) in 18 patients (24%), and progressive disease (PD) in two patients (2.7%). Of 70 patients treated with HD-CT, 41 patients (59%) showed a CR, 20 patients a PR (29%), eight patients a SD (11%), and one patient a PD (1.4%). The 5-yr overall survival for the entire group of patients was 29%, and for patients with NHL and HL 25%, and 38%, respectively. The respective event-free survival probabilities at 5 yr were 22%, 16%, and 31%. Seven treatment-related deaths due to septicemia (three), cardiac arrhythmia (one), pneumonia (one), pneumonitis (one), and toxic epidermal necrolysis (one) were observed. In multivariate analysis, an International Prognostic Index of > or = 2 and resistant disease to first-line chemotherapy were poor independent prognostic factors for the subgroup of patients with NHL. In conclusion, these results indicate that IVAD/CMV is feasible as a salvage therapy for lymphoma patients. This treatment is currently evaluated with the addition of rituximab.     

Allogeneic stem cell transplantation in patients with non-Hodgkin lymphoma who experienced relapse or progression after autologous stem cell transplantation

There are few treatment options for patients with non-Hodgkin lymphoma (NHL) who experienced progression after high-dose chemotherapy (HDC) with autologous stem cell transplantation (auto-SCT). The role of allogeneic stem cell transplantation (allo-SCT) in these patients has not been clarified yet. In this study, we report clinical outcomes of allo-SCT in patients with NHL who experienced progression after HDC with auto-SCT. Patients were enrolled from seven hospitals in Korea. A total of 38 patients were included: 18 patients (47.4%) underwent myeloablative conditioning and 20 patients (52.6%) reduced intensity conditioning. Overall response rate was 73.3%. Median event-free survival was 6.3 months. Median overall survival (OS) was 19.0 months. Estimated 5-year survival rate was 35.0%. Acute graft-versus-host disease developed in 13 patients (34.2%). Transplant-related mortality (TRM) was 21.1% (eight patients). Ann Arbor stage (p=0.022), performance status (p<0.001), and baseline serum albumin level (p=0.010) were significant risk factors for OS. Performance status (p=0.022) was a significant risk factor for TRM. Eight patients with persistent or progressive disease received donor lymphocyte infusion, and two of them achieved complete remission. In conclusion, despite high TRM, allo-SCT is a viable option for patients with NHL who underwent progression after HDC with auto-SCT.     

Upfront double high-dose chemotherapy with DICEP followed by BEAM and autologous stem cell transplantation for poor-prognosis aggressive non-Hodgkin lymphoma

A single center, prospective clinical trial was conducted evaluating 2 cycles of induction high-dose chemotherapy for adults younger than 65 years of age with aggressive non-Hodgkin lymphoma (NHL) and 2 to 3 Age-Adjusted International Prognostic Index risk factors. Patients received one cycle of standard dose cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) followed by one cycle of dose-intensive cyclophosphamide 5.25 g/m(2), etoposide 1.05 g/m(2), cisplatin 105 mg/m(2) (DICEP), then underwent autologous blood stem cell collection, followed by one cycle of high-dose carmustine (BCNU) 300 mg/m(2), etoposide 800 mg/m(2), Ara-C 1600 mg/m(2), melphalan 140 mg/m(2) (BEAM), and autologous stem cell transplantation (ASCT) and radiotherapy to prior bulk. From June 1998 to August 2004, 55 patients aged 20 to 63 years (median 44 years) were accrued, 51 (92%) of whom had diffuse large B-cell NHL. Poor prognostic factors included stage 4 (n = 46), elevated lactate dehydrogenase (LDH; n = 47), Eastern Cooperative Oncology Group (ECOG) performance status 2 to 4 (n = 43), bulky mass more than 10 cm (n = 34), and marrow involvement (n = 16). Only one patient experienced nonrelapse mortality. With a median follow-up of 49 months, 4-year event-free survival (EFS) and overall survival (OS) rates for all 55 patients are 72% (95% confidence interval [CI] = 60%-84%) and 79% (95% CI = 69%-90%), respectively. In conclusion, CHOP-DICEP-BEAM is feasible and gave encouraging EFS and OS for patients with poor-prognosis aggressive NHL.     

Ibritumomab tiuxetan radioimmunotherapy for patients with relapsed or refractory non-Hodgkin lymphoma and mild thrombocytopenia: a phase II multicenter trial

Mildly thrombocytopenic patients with relapsed or refractory low-grade non-Hodgkin lymphoma (NHL) have an increased risk of chemotherapy-induced myelosuppression following treatment. The safety and efficacy of radioimmunotherapy with a reduced dose of (90)Y ibritumomab tiuxetan (0.3 mCi/kg [11 MBq/kg]; maximum 32 mCi [1.2 GBq]) was evaluated in 30 patients with mild thrombocytopenia (100-149 x 10(9) platelets/L) who had advanced, relapsed or refractory, low-grade, follicular, or transformed B-cell NHL. The ibritumomab tiuxetan regimen included an infusion of rituximab (250 mg/m(2)) and injection of (111)In ibritumomab tiuxetan (5 mCi [185 MBq]) for dosimetry evaluation, followed 1 week later with rituximab (250 mg/m(2)) and (90)Y ibritumomab tiuxetan (0.3 mCi/kg [11 MBq/kg]). Patients (median age, 61 years; 90% stage III/IV at study entry; 83% follicular lymphoma; and 67% with bone marrow involvement) had a median of 2 prior therapy regimens (range, 1-9). Estimated radiation-absorbed doses were well below the study-defined maximum allowable for all 30 patients. With the use of the International Workshop criteria for NHL response assessment, the overall response rate was 83% (37% complete response, 6.7% complete response unconfirmed, and 40% partial response). Kaplan-Meier estimated median time to progression (TTP) was 9.4 months (range, 1.7-24.6). In responders, Kaplan-Meier estimated median TTP was 12.6 months (range, 4.9-24.6), with 35% of data censored. Toxicity was primarily hematologic, transient, and reversible. The incidence of grade 4 neutropenia, thrombocytopenia, and anemia was 33%, 13%, and 3%, respectively. Reduced-dose ibritumomab tiuxetan is safe and well tolerated and has significant clinical activity in this patient population.     

Autologous stem cell transplantation after conditioning with yttrium-90 ibritumomab tiuxetan plus BEAM in refractory non-Hodgkin diffuse large B-cell lymphoma: results of a prospective,multicenter, phase II clinical trial

Lymphoma patients with persistent disease undergoing autologous transplantation have a very poor prognosis in the rituximab era. The addition of radioimmunotherapy to the conditioning regimen may improve the outcome for these patients. In a prospective, phase 2 study, we evaluated the safety and efficacy of the addition of ⁹⁰Y-ibritumomab tiuxetan to the conditioning chemotherapy in patients with refractory diffuse large B-cell lymphoma. Thirty patients with induction failure (primary refractory; n=18) or refractory to salvage immunochemotherapy at relapse (n=12) were included in the study. The median age of the patients was 53 years (range, 25–67). All patients were given ⁹⁰Y-ibritumomab tiuxetan at a fixed dose of 0.4 mCi/kg (maximum dose 32 mCi) 14 days prior to the preparative chemotherapy regimen. Histological examination showed that 22 patients had de novo diffuse large B-cell lymphoma and eight had transformed diffuse large B-cell lymphoma. All patients had persistent disease at the time of transplantation, with 25 patients considered to be chemorefractory. The median time to neutrophil recovery (>500 white blood cells/μL) was 11 days (range, 9–21), while the median time to platelet recovery (>20,000 platelets/μL) was 13 days (range, 11–35). The overall response rate at day +100 was 70% (95% CI, 53.6–86.4) with 60% (95% CI, 42.5–77.5) of patients obtaining a complete response. After a median follow-up of 31 months for alive patients (range, 16–54), the estimated 3-year overall and progression-free survival rates are 63% (95% CI, 48–82) and 61% (95% CI, 45–80), respectively. We conclude that autologous transplantation with conditioning including ⁹⁰Y-ibritumomab tiuxetan is safe and results in a very high response rate with promising survival in this group of patients with refractory diffuse large B-cell lymphoma with a very poor prognosis. Study registered at European Union Drug Regulating Authorities Clinical Trials (EudraCT) N. 2007-003198-22.     

High-dose infusional ifosfamide,etoposide plus methylprednisolone followed by dexamethasone,high-dose ara-C and cisplatinum and autologous stem cell transplantation for refractory or relapsed aggressive non-Hodgkin's lymphoma

BACKGROUND AND OBJECTIVES: A salvage program including infusional high-dose ifosfamide plus etoposide (IFOVM) was evaluated in patients with refractory or relapsed aggressive non-Hodgkin's lymphoma. DESIGN AND METHODS: Forty-six patients were included. IFOVM consisted of ifosfamide (10 g/m2 as a 72-hour continuous infusion), etoposide (900 mg/m2) and methylprednisolone; responding patients underwent two cycles of DHAP and subsequently an autologous peripheral blood stem cell transplantation (APBSCT) with BEAM as the conditioning regimen. RESULTS: All but one patient showed tumor regression following IFOVM. Myelosuppression was brief but 26 patients developed neutropenic fever. All but two patients proceeded to DHAP. Overall response rate to IFOVM/DHAP was 59% (29% CR and 30% PR). Refractory patients had a significantly lower response rate than relapsed patients (39% vs. 85% p=0.002). All refractory patients with intermediate-high or high IPI progressed during IFOVM/DHAP. Twenty-seven patients proceeded to APBSCT. Two-year overall survival of patients with low or low-intermediate IPI was 47% [95% CI 25-69%], which was significantly better than that obtained in patients with intermediate-high or high IPI (11% [95% CI 0-22%] p=0.0001). INTERPRETATION AND CONCLUSIONS: This sequential regimen of IFOVM, followed by DHAP and consolidated with BEAM is active in relapsed or refractory patients with low or low-intermediate IPI aggressive lymphoma. However, it has little activity in those patients with intermediate or high IPI, especially in refractory lymphomas.     

Superior survival after replacing oral with intravenous busulfan in autologous stem cell transplantation for non-Hodgkin lymphoma with busulfan, cyclophosphamide and etoposide

Autologous stem cell transplantation (ASCT) with cyclophosphamide, etoposide and oral busulfan (BuCyVP) is an effective therapy for relapsed or refractory non-Hodgkin lymphoma (NHL). Substituting intravenous for oral busulfan reduces variability in drug exposure, potentially improving the safety and efficacy of the BuCyVP regimen. We retrospectively compared the outcomes of 604 consecutively treated patients who underwent ASCT for NHL with BuCyVP using oral ( n  = 468) or IV ( n  = 136) busulfan, without measurement of busulfan levels for pharmacokinetic (PK) analysis. Patients who received oral busulfan experienced more severe oral mucositis and a higher incidence of nonrelapse mortality. Median overall survival (OS) after ASCT was 72 months with oral busulfan but was not reached for the IV busulfan group. IV busulfan was associated with a lower rate of relapse, and superior relapse-free survival (RFS) and OS. In multivariate models, the route of busulfan administration was an independent prognostic factor for relapse ( P  = 0·01), RFS ( P  = 0·002) and OS ( P  = 0·001). IV busulfan appears to provide better efficacy and lower toxicity than oral busulfan in ASCT with BuCyVP for NHL. Whether PK-based busulfan dosing can achieve further improvements in this setting is worthy of study.     

Outpatient autologous hematopoietic stem cell transplantation for patients with relapsed follicular lymphoma

Autologous stem cell transplantation (ASCT) has emerged as a viable option for the treatment of relapsed follicular non-Hodgkin’s lymphoma. We report on the outpatient experience of 60 patients who underwent ASCT for this condition. The median age was 51 years (30–65). Pre-transplantation conditioning regimens consisted of either etoposide/melphalan/TBI, CBV or BEAM. Patients participated in this transplant program for a median of 20.5 days (14–78), and 58.4% of the total program days were spent in the outpatient setting. Six patients were well enough to be treated solely as outpatients. Ninety percent of patients required at least one inpatient admission (median 7 days), and 70% of first inpatient transfers occurred within the first week following transplant and always before day +12. There were no predictors for prolonged inpatient stays. Febrile neutropenia and gastrointestinal toxicity were the main reasons for inpatient transfers. No outpatient required an urgent admission to the ICU or died in the outpatient setting. The treatment-related mortality at days 30 and 100 was 0 and 1.7%, respectively. The overall and progression-free survivals at 5 years were 65.7 and 56.1%, respectively. Outpatient ASCT with total body irradiation is feasible, safe, and effective for patients with relapsed follicular lymphoma.     

Mitoxantrone, etoposide, cytarabine, and melphalan (NEAM) followed by autologous stem cell transplantation for patients with chemosensitive aggressive non-Hodgkin lymphoma

Patients with chemosensitive aggressive non-Hodgkin lymphoma (NHL) could benefit from high-dose chemotherapy (HDC) followed by autologous stem cell transplantation (auto-SCT). We report clinical outcomes of HDC using a novel regimen consisting of mitoxantrone, etoposide, cytarabine, and melphalan (NEAM) with auto-SCT. A total of 69 patients were consecutively enrolled. Median age was 42 years (range, 20-66 years). Median event-free survival (EFS) was 17.9 months. Median overall survival (OS) has not been reached yet and estimated 2-year OS was 64.2%. Among patients with measurable lesions, response rate was 79.5%. Median time to recovery of neutrophil (>500 mL) and platelet (gt;20,000 mL) was 12.5 and 13.5 days, respectively. Febrile neutropenia developed in 61 patients (88.4%). Grades 3 or 4 hepatic toxicity developed in 7 patients (10.1%), Grades 3 or 4 renal toxicity in 2 patients (2.9%), and Grade 3 or 4 cardiac toxicity in 2 patients (2.9%). Transplant-related mortality (TRM) developed in two patients (2.9%). Multiple prior treatments before transplantation, auxiliary bone marrow harvest for stem cell collection, and high serum lactate dehydrogenase level were related to unfavorable treatment outcomes. In conclusion, NEAM conditioning with auto-SCT demonstrated considerable efficacy with modest toxicity in patients with chemosensitive aggressive NHL.     

Lenalidomide maintenance following high-dose therapy and autologous haematopoietic stem cell transplantation in chemo-resistant or high-risk non-Hodgkin lymphoma: A phase I/II study

Improved maintenance treatments are needed for patients with relapsed/refractory aggressive lymphomas after autologous haematopoietic stem cell transplantation (ASCT). Several studies with lenalidomide have been found to have activity in the treatment of relapsed/refractory aggressive lymphomas. In the present phase I/II, single-arm, open-label study, 59 patients with high-risk relapsed non-Hodgkin lymphoma received pretransplant BEAM chemotherapy and ASCT followed by 12 months of maintenance lenalidomide once daily on Days 1–21 (28-day cycles) beginning at post-transplantation Day 100. The most common histologies were mantle cell lymphoma (56%) and diffuse large B-cell lymphoma (24%). The maximum tolerated dose in the dose-finding part of the study was 15 mg, but cytopenias led to the subsequent adoption of a 10 mg dose in the final study. Sixteen patients (27%) completed 12 cycles of lenalidomide maintenance. The most common reason for discontinuation was adverse events (31%). These were primarily haematologic, and 56% of patients experienced Grade 3–4 events. Two-year PFS rates (95% CIs) were 70% (56%–80%), 45% (19%–68%) and 81% (66%–90%); 2-year OS rates (95% CIs) were 91% (80%–96%), 93% (61%–99%) and 90% (76%–96%) in all patients, patients completing and patients not completing 12-month maintenance respectively. These results do not support the use of lenalidomide maintenance in this setting.