Prognosis of patients with acute lymphoblastic leukaemia relapsing after allogeneic stem cell transplantation.

The outcomes of patients with acute lymphoblastic leukaemia (ALL) presenting relapse after allogeneic stem cell transplant (allo-SCT) are poor, with few data available in this setting. OBJECTIVE AND METHODS: To evaluate the outcomes of patients with ALL presenting relapsed after allo-SCT, we performed a retrospective study including 132 from 11 centres in Spain. RESULTS: Therapeutic strategies consisted of palliative treatment (n = 22), chemotherapy (n = 82), tyrosine kinase inhibitors (n = 26), immunotherapy with inotuzumab and/or blinatumumab (n = 19), donor lymphocyte infusions (n = 29 pts), second allo-SCT (n = 37) and CAR T therapy (n = 14). The probability of overall survival (OS) at 1 and 5 years after relapse was 44% (95% confidence interval [CI]: 36%; 52%) and 19% (95% CI: 11%; 27%). In the 37 patients undergoing a second allo-SCT, the 5-year estimated OS probability was 40% [22%; 58%]. Younger age, recent allo-SCT, late relapse, 1st complete remission at 1st allo-SCT and chronic graft-versus-host disease confirmed their positive impact on survival in the multivariable analysis. CONCLUSION: Despite the poor prognosis of patients with ALL presenting relapse after a first allo-SCT, some can be satisfactorily rescued and a second allo-SCT still remains a valid option for selected patients. Moreover, emerging therapies really might improve ALL patients outcome when relapsing after an allo-SCT.

Treatment of steroid-refractory chronic graft-versus-host disease with imatinib: Real-life experience of the Spanish group of hematopoietic transplantation (GETH).

Treatment of steroid-refractory chronic graft-versus-host disease (cGVHD) is a challenge. Here, we describe a retrospective analysis of 66 patients with steroid-refractory cGVHD treated with imatinib (starting dose of 100 mg in 70% of patients; maximum dose of 100-200 mg in 74%). Most patients had multi-organ involvement (≥2 organs, 83%), with the most affected being skin (85%), oral mucosa (55%), eyes (42%), and lungs (33%). The overall response rate was 41% (21 partial and three complete responses). The organ with the best response rate was the skin (46%), followed by gastrointestinal tract (43%), liver (41%), the oral mucosa (36%), eyes (29%), and lungs (18%). Imatinib led to steroid tapering in 17/38 patients. Twenty-five (38%) patients experienced imatinib-related adverse events, comprising extra-hematologic toxicity (n = 24, 36%) and hematologic toxicity (n = 6, 9%). No cases of grade 4-5 toxicity were reported. The main causes of imatinib discontinuation were treatment failure (52%) and toxicity (9%). After a median follow-up of 41 months, the 3-year overall survival was 81%, with no difference between imatinib responders and non-responders. These real-life results show that imatinib is safe and has moderate efficacy in patients with heavily pre-treated cutaneous sclerotic cGVHD; however, activity against lung cGVHD is very limited.

Safety of obinutuzumab alone or combined with chemotherapy for previously untreated or relapsed/refractory chronic lymphocytic leukemia in the phase IIIb GREEN study.

The safety of obinutuzumab, alone or with chemotherapy, was studied in a non-randomized, open-label, non-comparative, phase IIIb study (GREEN) in previously untreated or relapsed/refractory chronic lymphocytic leukemia. Patients received obinutuzumab 1000 mg alone or with chemotherapy (investigator's choice of fludarabine-cyclophosphamide for fit patients, chlorambucil for unfit patients, or bendamustine for any patient) on days 1, 8 and 15 of cycle 1, and day 1 of cycles 2-6 (28-day cycles), with the cycle 1/day 1 dose administered over two days. The primary end point was safety/tolerability. Between October 2013 and March 2016, 972 patients were enrolled and 971 treated (126 with obinutuzumab monotherapy, 193 with obinutuzumab-fludarabine-cyclophosphamide, 114 with obinutuzumab-chlorambucil, and 538 with obinutuzumab-bendamustine). Grade ≥3 adverse events occurred in 80.3% of patients, and included neutropenia (49.9%), thrombocytopenia (16.4%), anemia (9.6%), and pneumonia (9.0%); rates were similar in first-line and relapsed/refractory patients, and in first-line fit and unfit patients. Using expanded definitions, infusion-related reactions were observed in 65.4% of patients (grade ≥3, 19.9%; mainly seen during the first obinutuzumab infusion), tumor lysis syndrome in 6.4% [clinical and laboratory; highest incidence with obinutuzumab-bendamustine (9.3%)], and infections in 53.7% (grade ≥3, 20.1%). Serious and fatal adverse events were seen in 53.1% and 7.3% of patients, respectively. In first-line patients, overall response rates at three months post treatment exceeded 80% for all obinutuzumab-chemotherapy combinations. In the largest trial of obinutuzumab to date, toxicities were generally manageable in this broad patient population. Safety data were consistent with previous reports, and response rates were high. (clinicaltrials.gov identifier: 01905943).

Characterization of Chronic Graft-versus-host Disease After Haploidentical Stem Cell Transplantation With Posttransplant Cyclophosphamide: A Study on Behalf of GETH-TC.

BACKGROUND: Chronic graft-versus-host disease (cGVHD) is a cause of late morbidity and nonrelapse mortality (NRM) after allogenic hematopoietic stem cell transplantation (allo-HSCT). Although studies evaluating haploidentical allo-HSCT (haplo-HSCT) using posttransplant cyclophosphamide (PTCy) demonstrate lower cGVHD rates, comprehensive data describing the clinical profile, risk factors, or outcomes of cGVHD within this platform are scarce. METHODS: We conducted a retrospective multicenter analysis of 389 consecutive patients who underwent haplo-HSCT PTCy in 7 transplant centers of the Spanish Group Grupo Español de Trasplante Hematopoyético y Terapia Celular (GETH-TC) between 2008 and 2020 describing incidence, clinical profile, risk factors, and cGVHD outcomes. RESULTS: Ninety-five patients of 389 developed cGVHD. Our data revealed that the incidence and severity of cGVHD are lower than those reported for HLA-identical transplantation with conventional prophylaxis and that the strongest predictor for cGVHD was previous acute GVHD ( P  = 0.031). Also, recipient age ≥60 y ( P  = 0.044) was protective against cGVHD. Moreover, patients with moderate cGVHD had longer event-free survival at 3 y than other patients ( P  = 0.016) and a lower relapse rate at 3 y ( P  = 0.036). CONCLUSIONS: Our results support the fact that the incidence and severity of cGVHD are lower than those reported for HLA-identical transplantation with conventional prophylaxis. In this series, patients who develop moderate cGVHD after haplo-HSCT PTCy had a higher overall survival and event-free survival, and lower relapse, suggesting higher graft-versus-leukemia effect. Although this is the largest series focused on characterizing cGVHD in haplo-HSCT PTCy, further prospective studies are needed to confirm the findings.

Dynamics of virological and immunological markers of HIV persistence after allogeneic haematopoietic stem-cell transplantation in the IciStem cohort: a prospective observational cohort study.

BACKGROUND: Allogeneic haematopoietic stem-cell transplantation (allo-HSCT) markedly reduces HIV reservoirs, but the mechanisms by which this occurs are only partly understood. In this study, we aimed to describe the dynamics of virological and immunological markers of HIV persistence after allo-HSCT. METHODS: In this prospective observational cohort study, we analysed the viral reservoir and serological dynamics in IciStem cohort participants with HIV who had undergone allo-HSCT and were receiving antiretroviral therapy, ten of whom had received cells from donors with the CCR5Δ32 mutation. Participants from Belgium, Canada, Germany, Italy, the Netherlands, Spain, Switzerland, and the UK were included in the cohort both prospectively and retrospectively between June 1, 2014 and April 30, 2019. In the first 6 months after allo-HSCT, participants had monthly assessments, with annual assessments thereafter, with the protocol tailored to accommodate for the individual health status of each participant. HIV reservoirs were measured in blood and tissues and HIV-specific antibodies were measured in plasma. We used the Wilcoxon signed-rank test to compare data collected before and after allo-HSCT in participants for whom longitudinal data were available. When the paired test was not possible, we used the Mann-Whitney U test. We developed a mathematical model to study the factors influencing HIV reservoir reduction in people with HIV after allo-HSCT. FINDINGS: We included 30 people with HIV with haematological malignancies who received a transplant between Sept 1, 2009 and April 30, 2019 and were enrolled within the IciStem cohort and included in this analysis. HIV reservoirs in peripheral blood were reduced immediately after full donor chimerism was achieved, generally accompanied by undetectable HIV-DNA in bone marrow, ileum, lymph nodes, and cerebrospinal fluid, regardless of donor CCR5 genotype. HIV-specific antibody levels and functionality values declined more slowly than direct HIV reservoir values, decaying significantly only months after full donor chimerism. Mathematical modelling suggests that allogeneic immunity mediated by donor cells is the main viral reservoir depletion mechanism after massive reservoir reduction during conditioning chemotherapy before allo-HSCT (half-life of latently infected replication-competent cells decreased from 44 months to 1·5 months). INTERPRETATION: Our work provides, for the first time, data on the effects of allo-HSCT in the context of HIV infection. Additionally, we raise the question of which marker can serve as the last reporter of the residual viraemia, postulating that the absence of T-cell immune responses might be a more reliable marker than antibody decline after allo-HSCT. FUNDING: amfAR (American Foundation for AIDS Research; ARCHE Program), National Institutes of Health, National Institute of Allergy and Infectious Diseases, and Dutch Aidsfonds.

Post-transplant cyclophosphamide compared to sirolimus/tacrolimus in reduced intensity conditioning transplants for patients with lymphoid malignancies.

Despite novel cellular and immunomodulatory therapies, allogeneic hematopoietic stem cell transplantation (HSCT) remains a treatment option for lymphoid malignancies. Post-transplant cyclophosphamide (PTCY) is increasingly employed for graft vs. host disease (GVHD) prophylaxis. This study aims to evaluate the safety and efficacy of PTCY in reduce intensity (RIC) HSCT for patients with lymphoid neoplasms compared to sirolimus with tacrolimus (SIR/TAC). The primary endpoint was to compare grade III-IV acute GVHD, severe chronic GVHD, and relapse-free survival (GRFS) between the two GVHD prophylaxis strategies. This study, conducted from January 2012 to December 2020, included 171 consecutive patients (82 in the PTCY and 89 in the SIR/TAC group). Results revealed a significantly decreased incidence of moderate and severe forms of chronic GVHD in PTCY cohort (5.8% [95% CI, 1.8 to 13.1]) versus the SIR/TAC cohort (39.6% [95% CI, 29.3 to 49.7] (p < 0.001)). Other outcomes, including GRFS (PTCY [45.9% (95% CI, 35.8-58.7)] and SIR/TAC groups [36.8% (95% CI, 28-48.4)], (p = 0.72)), non-relapse mortality (NRM), relapse and overall survival (OS) were similar in both groups. Interestingly, the failure to achieve GRFS was mainly attributed to GVHD in the SIR/TAC group, while disease relapse was the primary reason in the PTCY cohort.

Impact of risk scores in outcome of patients with myeloid neoplasms after allogeneic stem cell transplant.

BACKGROUND: The main causes of failure of allogeneic hematopoietic stem cell transplantation (allo-transplant) in patients with acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS) are relapse and transplant-related mortality. Different scores have been designed to predict the prognosis of these patients. The objective of this study was to assess which score or combination has better outcome predictive capacity. METHODS: Retrospective analysis of patients with AML and MDS who received a first peripheral blood allo-transplant in a single center, between December 2001 and October 2019. Hematopoietic Cell Transplantation Comorbidity Index (HCT-CI), European Group for Blood and Marrow Transplantation (EBMT) and Disease Risk Index (DRI) scores were calculated. For each score and for the HCT-CI/DRI and HCT-CI/EBMT combinations, overall survival (OS), cumulative incidence of relapse (CIR), non-relapse-related mortality (NRM), and graft versus host disease-free relapse-free survival (GRFS) were analyzed. RESULTS: 175 patients were evaluated. With a median (range) follow-up of 3.96 (0.32-17.22) years, the 5-year probabilities (95% CI) of OS, CIR, NRM, and GRFS were 36% (28%-44%), 28% (21%-35%), 38% (30%-46%) and 24% (17%-31%), respectively. For OS, only the DRI score selected two groups with statistically significant differences (DRI 0-1: 41% vs. DRI ≥2: 24%; p=0.011). The combination of DRI 0-1 and HCT-CI 0-2 showed OS probabilities of 45% vs. 26% for those with DRI 0-1 and HCT-CI ≥3; p=0.041. CONCLUSIONS: In patients with AML and MDS submitted to allo-transplant, the combination of HCT-CI and DRI scores provided the best stratification for OS.

Low doses of gemtuzumab ozogamicin in adults diagnosed with acute myeloid leukaemia. / Gemtuzumab ozogamicina a bajas dosis en adultos con leucemia mieloide aguda.

BACKGROUND: Gemtuzumab ozogamicin (GO) is a monoclonal antibody with significant activity in CD33+acute myeloid leukaemia (AML). At doses of 9mg/m2, its benefit was limited by hepatotoxicity and sinusoidal obstruction syndrome (SOS). Fractionated doses improved toxicity without compromising efficacy. We evaluated the efficacy and the toxicity of low doses of GO. METHODS: Twenty-four patients with AML received 3mg/m2 of GO as a part of the induction or reinduction therapy. RESULTS: Fourteen patients diagnosed with de novo AML and 10 patients with relapsed or refractory (R/R) AML received GO as a part of the induction or reinduction therapy. Three and no cases of hepatotoxicity were observed, respectively. Thirteen patients received a subsequent haematopoietic stem cell transplantation (HSCT) after GO therapy. Hepatotoxicity was observed in 2 patients and no SOS was observed in any patient. CONCLUSIONS: The administration of low dose GO is feasible and does not have impact on subsequent HSCT outcome. Although some degree of hepatotoxicity was observed, there were no cases of SOS, either before or after HSCT.

Ruxolitinib in refractory acute and chronic graft-versus-host disease: a multicenter survey study.

Graft-versus-host disease is the main cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation. First-line treatment is based on the use of high doses of corticosteroids. Unfortunately, second-line treatment for both acute and chronic graft-versus-host disease, remains a challenge. Ruxolitinib has been shown as an effective and safe treatment option for these patients. Seventy-nine patients received ruxolitinib and were evaluated in this retrospective and multicenter study. Twenty-three patients received ruxolitinib for refractory acute graft-versus-host disease after a median of 3 (range 1-5) previous lines of therapy. Overall response rate was 69.5% (16/23) which was obtained after a median of 2 weeks of treatment, and 21.7% (5/23) reached complete remission. Fifty-six patients were evaluated for refractory chronic graft-versus-host disease. The median number of previous lines of therapy was 3 (range 1-10). Overall response rate was 57.1% (32/56) with 3.5% (2/56) obtaining complete remission after a median of 4 weeks. Tapering of corticosteroids was possible in both acute (17/23, 73%) and chronic graft-versus-host disease (32/56, 57.1%) groups. Overall survival was 47% (CI: 23-67%) at 6 months for patients with aGVHD (62 vs 28% in responders vs non-responders) and 81% (CI: 63-89%) at 1 year for patients with cGVHD (83 vs 76% in responders vs non-responders). Ruxolitinib in the real life setting is an effective and safe treatment option for GVHD, with an ORR of 69.5% and 57.1% for refractory acute and chronic graft-versus-host disease, respectively, in heavily pretreated patients.

Autologous stem cell transplantation and purging in adult acute lymphoblastic leukaemia.

The prognosis for adult acute lymphoblastic leukaemia (ALL) is poor. Only 20-30% of patients will be cured with conventional chemotherapy. Haematopoietic progenitor transplantation is thus an attractive option in these patients. Even if allogeneic transplantation allows a better control of the disease, autologous transplantation remains an important alternative for patients lacking a suitable donor or when allogeneic transplants imply excessive risk. Relapse is the main drawback of autologous transplants, but many strategies are being explored to overcome this problem. We focus here on transplant modality, the source of haematopoietic progenitors, and the best timing to apply the procedure. Also reviewed are the current situation and future strategies for improving results in this setting, such as ex vivo purging; immunotherapy and maintenance chemotherapy.