Haploidentical allogeneic hematopoietic cell transplantation in adults using CD3/CD19 depletion and reduced intensity conditioning: a phase II study

Background We report a prospective multicenter phase II study of haploidentical hematopoietic stem cell transplantation using CD3/CD19-depleted grafts after reduced intensity conditioning with fludarabine, thiotepa, melphalan and OKT-3. DESIGN AND METHODS: Sixty-one adults with a median age of 46 years (range 19-65 years) have been enrolled. Diagnoses were acute myeloid leukemia (n=38), acute lymphoblastic leukemia (n=8), non-Hodgkin's lymphoma (n=6), myeloma (n=4), chronic myeloid leukemia (n=3), chronic lymphatic leukemia (n=1) and myelodysplastic syndrome (n=1). Patients were considered high risk because of refractory disease (n=18), cytogenetics (n=6), complete remission (≥2) (n=9), chemosensitive relapse in partial remission (n=4) or relapse after prior hematopoietic stem cell transplantation (n=15 allogeneic, n=8 autologous, n=1 both). At haploidentical hematopoietic stem cell transplantation, 30 patients were in complete remission and 31 in partial remission. Grafts contained a median of 7.0×10(6) (range 3.2-22) CD34(+) cells/kg, 4.2×10(4) (range 0.6-44) CD3(+) T cells/kg and 2.7×10(7) (range 0.00-37.3) CD56(+) cells/kg. RESULTS: Engraftment was rapid with a median of 12 days to granulocytes more than 0.5×10(9)/L (range 9-50 days) and 11 days to platelets more than 20×10(9) (range 7-38 days). Incidence of grade IIIV acute graft-versus-host-disease and chronic graft-versus-host-disease was 46% and 18%, respectively. Non-relapse mortality on Day 100 was 23% and 42% at two years. Cumulative incidence of relapse/progression at two years was 31%. Kaplan-Meier estimated 1-year and 2-year overall survival with median follow up of 869 days (range 181-1932) is 41% and 28%, respectively. Conclusions This regimen allows successful haploidentical hematopoietic stem cell transplantation with reduced intensity conditioning in high-risk patients lacking a suitable donor. (clinicaltrials.gov identifier:NCT00202917).     

Haploidentical allogeneic hematopoietic cell transplantation in adults with reduced-intensity conditioning and CD3/CD19 depletion: fast engraftment and low toxicity

OBJECTIVE: CD3/CD19 depletion may improve engraftment and immune reconstitution after haploidentical hematopoietic cell transplantation (HHCT) as grafts not only contain CD34+ stem cells but also CD34- progenitors and natural killer, dendritic, and facilitating cells. PATIENTS AND METHODS: Ten consecutive patients received HHCT with CD3/CD19-depleted grafts. Reduced-intensity conditioning was performed with fludarabine (150-200 mg/m2), thiotepa (10 mg/kg), melphalan (120 mg/m2), and OKT-3 (5 mg/day, day -5 to +14) without additional posttransplant immunosuppression. Diagnoses were AML (n = 4), ALL (n = 3), NHL (n = 2), and multiple myeloma (n = 1). All patients were "high risk" with refractory disease or relapse after preceding HCT. The CD3/CD19-depleted haploidentical grafts contained a median of 7.8 x 10(6) (range, 5.2-17 x 10(6)) CD34+ cells/kg, 5.5 x 10(7) (range, 0.02-8.6 x 10(7)) CD56+ cells/kg, and 2.0 x 10(4) (range, 0.006-44 x 10(4)) CD3+ T cells/kg. Engraftment was rapid with median time to greater than 500 granulocytes/microL of 13 (range, 11-17) days, greater than 20,000 platelets/microL of 11 (range, 8-16) days, and full donor chimerism after 2 weeks in all patients. Six cases of grade II GVHD occurred. One patient, who received the highest T cell dose, developed lethal grade IV GVHD. Treatment-related mortality in the first 100 days was 3/10 (30%) with one death each due to idiopathic pneumonia syndrome, GVHD, and CMV disease. Two patients died after day 100, one due to relapse and one with systemic adenoviral infection. Overall survival is 5/10 patients (50%) with a median follow-up of 435 (range, 229-814) days. CONCLUSION: This regimen is promising in high-risk patients lacking a suitable donor, and a prospective phase I/II study is ongoing.     

Role of reduced intensity conditioning in allogeneic hematopoietic cell transplantation for patients with multiple myeloma

High-dose chemotherapy followed by autologous hematopoietic cell transplantation continues to play an integral role in the treatment strategy in patients with newly diagnosed multiple myeloma. Incorporation of newer potent anti-myeloma agents has further improved outcomes. However, disease relapse or progression remains a challenge after autologous transplantation. Allogeneic hematopoietic cell transplantation remains the only potentially curative modality for some patients due in part to graft-versus-myeloma effect. High transplant-related mortality, in the range of 30% to 40%, previously seen with myeloablative conditioning regimens, including total body irradiation plus cyclophosphamide has been significantly reduced by introducing less ablative preparative regimens, so called reduced-intensity conditioning. Cumulative evidence suggests encouraging prospects for allogeneic transplantation through improved outcomes of myeloma patients (overall survival exceeding 70% at 2 years in some studies); however, which patient population would benefit most from this treatment remains to be defined. newer strategies to augment graft-versus-myeloma effect and minimize post transplant toxicities are in need of further improvement in patients with myeloma.     

Alveolar hemorrhage following allogeneic hematopoietic cell transplantation using reduced-intensity conditioning

Allogeneic hematopoietic cell transplantation (HCT) using reduced-intensity conditioning (RIC) has lower morbidity and mortality compared to transplantation using myeloablative conditioning (MAC). The syndrome of alveolar hemorrhage, a life-threatening pulmonary complication of HCT, has not been well described after RIC HCT. We reviewed prospectively collected data on 206 RIC and 1112 MAC HCT performed between 1995 and 2004 to study the impact of conditioning regimen on the clinical features and outcome of alveolar hemorrhage. Alveolar hemorrhage occurred in 18 RIC HCT recipients (cumulative incidence 8% (95% confidence intervals (CI), 5-11%)) and 85 MAC HCT recipients (cumulative incidence 7% (95% CI, 6-8%), P = 0.56). The clinical presentation of hemorrhage in both cohorts was similar. Survival at 60 days from the onset of hemorrhage was 28% (95% CI, 7-49%) for RIC group compared to 26% (95% CI, 17-35%) after MAC HCT (P = 0.56). Reducing the intensity of preparative regimen does not protect against post transplant alveolar hemorrhage. Alveolar hemorrhage occurring after RIC or MAC HCT has similar incidence, clinical presentation, and associated high mortality.     

Graft-versus-myeloma effect following antithymocyte globulin-based reduced intensity conditioning allogeneic stem cell transplantation

In all, 41 multiple myeloma (MM) patients received an antithymocyte globulin (ATG), fludarabine, and busulfan-based reduced intensity conditioning (RIC) for allogeneic stem cell transplantation (allo-SCT) from HLA-identical siblings. In total, 29 patients (70%) were in partial remission, one patient in complete remission, and 11 (27%) with progressive disease at the time of allo-SCT. Median time between diagnosis and allo-SCT was 24 months. The cumulative incidences of grade II-IV and grade III-IV acute graft-versus-host disease (GVHD) were 36% (95% CI, 21-51%) and 7% (95% CI, 2-20%), respectively. Overall, 10 patients developed limited chronic GVHD, whereas seven developed an extensive form (cumulative incidence, 41% (95% CI, 26-56%) at 2 years). With a median follow-up of 389 days, the overall cumulative incidence of transplant-related mortality (TRM) was 17% (95% CI, 6-28%). In all, 11 patients (27%) are in continuous complete remission, and the Kaplan-Meier estimates of overall survival (OS) and progression-free survival (PFS) at 2 years were 62% (95% CI, 47-76%) and 41% (95% CI, 23-62%), respectively. PFS and OS were significantly higher in patients with chronic GVHD as compared to patients without chronic GVHD (P=0.006 for PFS and P=0.01 for OS). Collectively, these data demonstrate that RIC allo-SCT can mediate a potentially curative graft-versus-myeloma effect with an acceptable incidence of toxicity and TRM.     

Engraftment and survival following hematopoietic stem cell transplantation for osteopetrosis using a reduced intensity conditioning regimen

Autosomal recessive osteopetrosis (OP) is a disease characterized by osteoclast dysfunction, leading to multisystem morbidity and death of most affected children. Hematopoietic stem cell transplantation (HSCT) is the treatment of choice for OP, but this patient population is particularly prone to post-transplant complications and death after myeloablative conditioning. To determine the potential of achieving improved overall outcomes in these patients by decreasing pre-transplant mortality, we investigated engraftment and survival following a reduced intensity regimen including busulfan, fludarabine and total lymphoid irradiation. We report outcomes in 11 patients. All six patients who received a bone marrow or peripheral stem cell graft engrafted with >75% donor chimerism. In contrast, all five recipients of unrelated cord blood as a stem cell source for a first graft failed to demonstrate donor hematopoietic chimerism. The day 100 and 6-month mortality was low at 9%. One year after HSCT, six of 11 patients (55%) were surviving. Our data suggest that this regimen results in low peri-transplant mortality without compromising engraftment when a marrow or peripheral stem cell graft is used. An umbilical cord blood graft, however, should be used with caution for patients with OP when this or a similar reduced intensity regimen is used.     

Secondary solid cancers after allogeneic hematopoietic cell transplantation using busulfan-cyclophosphamide conditioning

Risks of secondary solid cancers among allogeneic hematopoietic cell transplant (HCT) recipients who receive conditioning without total body irradiation are not well known. We evaluated the incidence and risk factors for solid cancers after HCT using high-dose busulfan-cyclophosphamide conditioning in 4318 recipients of first allogeneic HCT for acute myeloid leukemia in first complete remission (N = 1742) and chronic myeloid leukemia in first chronic phase (N = 2576). Our cohort represented 22 041 person-years at risk. Sixty-six solid cancers were reported at a median of 6 years after HCT. The cumulative-incidence of solid cancers at 5 and 10 years after HCT was 0.6% and 1.2% among acute myeloid leukemia and 0.9% and 2.4% among chronic myeloid leukemia patients. In comparison to general population incidence rates, HCT recipients had 1.4× higher than expected rate of invasive solid cancers (95% confidence interval, 1.08-1.79, P = .01). Significantly elevated risks were observed for tumors of the oral cavity, esophagus, lung, soft tissue, and brain. Chronic graft-versus-host disease was an independent risk factor for all solid cancers, and especially cancers of the oral cavity. Recipients of allogeneic HCT using busulfan-cyclophosphamide conditioning are at risk for developing solid cancers. Their incidence continues to increase with time, and lifelong cancer surveillance is warranted in this population.     

Intravenous busulfan-based conditioning prior to allogeneic hematopoietic stem cell transplantation: myeloablation with reduced toxicity

OBJECTIVE: Allogeneic transplantation is a potentially curative treatment for hematologic malignancies but is associated with a high rate of complications. Busulfan is a common component of pretransplant conditioning but has an erratic and unpredictable bioavailability when administered orally. Intravenous (IV) busulfan was recently introduced into clinical practice. Prior studies showed consistent and predictable drug delivery with tight control of busulfan plasma levels, avoiding over- and under-dosing. This study was designed to define the role of IV busulfan in different transplant and disease settings. PATIENTS AND METHODS: The study included 43 patients with various hematologic malignancies conditioned with high-dose IV busulfan-containing regimens prior to allogeneic transplantation. The donors were HLA-matched siblings (n=24), matched unrelated (n=14), or 1-antigen mismatched related donors (n=5). Outcome parameters were recorded. RESULTS: Forty-two patients had initial engraftment. The toxicity profile was favorable. No patient developed veno-occlusive disease of the liver. Acute graft-vs-host disease (GVHD) grades II-IV occurred in 18 patients (42%). Six patients died of treatment-related causes, five of complications related to acute GVHD, and only one died of organ toxicity. Actuarial non-relapse-related mortality risk was 10% at day 100 and 18% at 2 years posttransplant. The actuarial 2-year overall survival and disease-free survival (DFS) rates were 63% and 44%, respectively. Disease status other than refractory relapse, myeloid disease, and no severe GVHD posttransplant predicted for longer DFS in a multivariant model. CONCLUSIONS: IV busulfan-containing regimens allow consistent engraftment of allografts from related and unrelated donors such that myeloablation is administered with a toxicity profile typical of non-myeloablative conditioning. Favorable outcome was seen in patients with myeloid leukemias and in early or intermediately advanced disease; however, this regimen may not be sufficiently cytoreductive in patients with very advanced or active leukemia and in acute lymphoblastic leukemia. IV busulfan merits further study to better define its role as a preferred substitute for oral busulfan in pretransplant conditioning.     

Acute GVHD is a strong predictor of full donor CD3+ T cell chimerism after reduced intensity conditioning allogeneic stem cell transplantation

The monitoring of chimerism is a standard procedure to assess engraftment and achievement of full donor lymphoid cells after reduced intensity conditioning (RIC) stem cell transplantation (Allo‐SCT). However, there is no consensus on when and how often to monitor post‐transplant chimerism. We retrospectively analyzed our experience regarding the impact of acute graft versus host disease (GVHD) for the prediction of allograft chimerism. One‐hundred‐and‐fifteen patients transplanted between 2001 and 2010 were identified. This group included 57 females and 58 males with a median age of 50 years (range: 26–68). Patients evaluated in this study were adult patients with hematologic malignancies, who received transplants from an HLA‐matched sibling donor or matched unrelated donor (MUD) at allele level so‐called 10/10, and received the RIC regimen including fludarabine/busulfan and anti‐thymoglobulin (ATG). Mixed T‐cell chimerism was defined as between 5 and 94% recipient cells, and full chimerism was defined as the presence of more than 95% donor T‐cell chimerism (TCC). Full donor TCC was achieved in 93 patients (81%) at a median of 77 days (range: 30–120) post‐transplant. The cumulative incidence of Grade 2–4 GVHD in our population was 25% (95% CI 17–34). The analysis of the population of patients with acute GVHD grade ≥2 showed that at day 120 after Allo‐SCT they all had a total full donor TCC. On the other hand, 78 (68%) patients without acute GVHD grade ≥2 presented with mixed chimerism (p = 0.002) on day 120 post‐transplant. Interestingly, patients who received ATG 5 mg/kg obtained a higher probability of complete chimerism compared with those receiving 2.5 mg/kg (p = 0.03). In conclusion, our study demonstrates that acute GVHD was predictive of full donor TCC after RIC Allo‐SCT. Therefore, our data may challenge the concept of the frequent or close monitoring of donor chimerism in some patients with ongoing acute GVHD. However, chimerism testing could represent an attractive modality for minimal residual disease detection or for impeding relapse warranting further prospective studies. Am. J. Hematol. 2012. © 2012 Wiley Periodicals, Inc.     

KIR haplotype B donors but not KIR-ligand mismatch result in a reduced incidence of relapse after haploidentical transplantation using reduced intensity conditioning and CD3/CD19-depleted grafts

Natural killer (NK)-cell alloreactivity after allogeneic hematopoietic cell transplantation (HCT) is influenced by the interaction of killer-cell immunoglobulin-like receptors (KIRs) on donor NK cells and human leukocyte antigen (HLA) class I ligands on recipient cells. We investigated the influence of donor KIR haplotype and KIR-ligand mismatch (MM) on relapse in 57 patients with hematologic malignancies receiving haploidentical HCT after reduced intensity conditioning and graft CD3/CD19 depletion. Of the 57 donors, 17 had KIR haplotype A (29.8 %) and 40 had KIR haplotype B (70.2 %). A KIR-ligand MM was found in 34 of 57 patients (59.6 %). There was no difference between donor KIR haplotypes in non-relapse mortality (NRM, p?=?0.200) but had a significantly reduced incidence of relapse for patients with a haplotype B donor (p?=?0.001). In particular, patients in partial remission (PR) benefited more from a haplotype B graft (p?=?0.008) than patients in complete remission (CR, p?=?0.297). Evaluating KIR-ligand MM cumulative incidences of relapse (p?=?0.680) or NRM (p?=?0.579), we found no significant difference. In conclusion, in the setting of reduced intensity conditioning (RIC) and CD3/CD19-depleted haploidentical HCT, we could not confirm the positive data with KIR-ligand MM but observed a significant lower risk of relapse with a KIR haplotype B donor.     

Fludarabine vs cladribine plus busulfan and low-dose TBI as reduced intensity conditioning for allogeneic hematopoietic stem cell transplantation: a prospective randomized trial

Purine analogs are often used for conditioning preceding allogeneic hematopoietic stem cell transplantation (HCT). We prospectively tested fludarabine (Flu) 40 mg/m(2)/day x 5 days vs cladribine (Clad) 10 mg/m(2)/day x 5 days plus oral busulfan (1 mg/kg q6 h x 2 days) and total body irradiation 200 cGy in 32 recipients of matched sibling and unrelated donor (URD) HCT. Patients were similar in age (median 52 years), diagnosis, extensive pre-HCT therapy (56 vs 63%), and high-risk disease status (81 vs 93%). Neutrophil engraftment was prompt (median 11 vs 12 days), but early graft failure using Clad halted randomization. Platelet recovery was prompt (median Flu 18 vs Clad 24 days). Graft-versus-host disease (GVHD) after Flu vs Clad was similar; (acute grade II/IV 56 vs 69%, P=0.26; chronic 50 vs 31%, P=0.27). Nonrelapse mortality (Flu 25 vs Clad 38%, P=0.47) and progression-free survival at 3 years were similar as well. Multivariate analyses showed slightly, but not significantly lower relative risk (RR) of neutrophil engraftment with Clad (RR 0.6 (95% CI 0.2-1.3) P=0.16) and with URD RR 0.4 (0.2-1.0) P=0.04). Older patients with advanced hematologic malignancies achieve satisfactory outcomes using either of these reduced intensity conditioning regimens.     

Clonal cytogenetic changes and myeloma relapse after reduced intensity conditioning allogeneic transplantation

To identify a correlation between metaphase cytogenetics and relapse after reduced intensity conditioning (RIC) allotransplant for patients with multiple myeloma, data on 60 patients (median age 52) who received grafts from a sibling (n = 49) or unrelated donor (n = 11) were analyzed. Fifty-three patients (88%) showed chromosomal abnormalities (CA) before the allotransplant, including 42 with abnormalities involving 13q (CA13). Twenty-two patients (41%) relapsed post-allotransplant at a median of 165 days. Of these, 11 patients showed abnormal cytogenetics at the time of post-allotransplant relapse at a median of 167 days. Of 54 patients who developed graft-versus-host disease, relapse occurred in 19 of 48 patients (43%) with CA present before RCI allotransplant, versus 1 of 6 without CA (17%) (P = 0.06). Loss of CA before RIC allotransplant and disease status > PR after RIC allotransplant were significantly associated with a lower risk of post-allotransplant relapse with cytogenetic abnormalities; 5.2 vs 36%, and 18 vs 53%, (both P < 0.05), respectively. The current data suggests that myeloma associated with persistent clonal cytogenetic abnormalities is an entity which most likely escapes the effects of a graft versus myeloma activity, maybe because of acquisition of resistance to immunologic manipulations.