Low non-relapse mortality and good haematological and renal responses after autologous haematopoietic stem cell transplantation in multiple myeloma patients with renal insufficiency at transplant: A prospective Société Francophone de Greffe de Moelle-Thérapie Cellulaire observational study

High-dose melphalan followed by autologous haematopoietic stem cell transplantation is widely used in newly diagnosed multiple myeloma (MM) patients as upfront therapy. However, the safety and efficacy of transplantation in patients with renal insufficiency (RI) are controversial. We followed a multicentre (16 SFGM-TC centres) prospective cohort of 50 newly diagnosed MM patients with a serum creatinine clearance of <40 mL/min at transplantation. Patients received a recommended dose of melphalan of 140 mg/m2. The primary end-point was the non-relapse mortality at Day 100. One death occurred during the first 100 days post-transplant. The median time to neutrophil engraftment was 12 days and to platelet engraftment was 13 days. The haematological response improved in 69% of patients, with best responses from partial response (PR) to very good partial response (VGPR) (10%), from PR to complete response (CR)/stringent complete response (sCR) (16%), from VGPR to CR/sCR (39%) and from CR to sCR (2%). At 2 years, the overall survival was 84%, the progression-free survival was 70% and the cumulative incidence of relapse was 20%. The renal response improved in 59% of patients, with the best renal responses post-transplant being minimal (9%), partial (2%) and complete (48%). Autologous transplantation was safe and effective in myeloma patients with RI at transplant.

[Unrelated donor selection for allogeneic hematopoietic stem cell transplantation: Guidelines from the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC)]

The selection of a donor is an essential element in allogeneic hematopoietic stem cell transplantation. In the absence of an HLA-matched related donor, the selection of an unrelated donor is considered, and is currently the most common type of allogenic donor used in practice. Many criteria are considered for the selection when multiple donors are available, particularly in case of partial match. The aim of this workshop is to assist in the selection of an unrelated donor, in keeping with recent data from the literature.

Bone marrow graft versus peripheral blood graft in haploidentical hematopoietic stem cells transplantation: a retrospective analysis in1344 patients of SFGM-TC registry

The use of peripheral blood (PB) or bone marrow (BM) stem cells graft in haploidentical hematopoietic stem cell transplantation with post-transplant cyclophosphamide (PTCy) for graft-versus-host disease (GVHD) prophylaxis remains controversial. Moreover, the value of adding anti-thymoglobulin (ATG) to PTCy is unknown. A total of 1344 adult patients received an unmanipulated haploidentical transplant at 37 centers from 2012 to 2019 for hematologic malignancy. We compared the outcomes of patients according to the type of graft, using a propensity score analysis. In total population, grade II-IV and III-IV acute GVHD (aGVHD) were lower with BM than with PB. Grade III-IV aGVHD was lower with BM than with PB + ATG. All outcomes were similar in PB and PB + ATG groups. Then, in total population, adding ATG does not benefit the procedure. In acute leukemia, myelodysplastic syndrome and myeloproliferative syndrome (AL-MDS-MPS) subgroup receiving non-myeloablative conditioning, risk of relapse was twice greater with BM than with PB (51 vs. 22%, respectively). Conversely, risk of aGVHD was greater with PB (38% for aGVHD II-IV; 16% for aGVHD III-IV) than with BM (28% for aGVHD II-IV; 8% for aGVHD III-IV). In this subgroup with intensified conditioning regimen, risk of relapse became similar with PB and BM but risk of aGVHD III-IV remained higher with PB than with BM graft (HR = 2.0; range [1.17-3.43], p = 0.012).

Allogeneic hematopoietic stem cell transplantation for adults with therapy-related acute myeloid leukaemia: a retrospective multicentre study on behalf of the SFGM-TC

We report the results from a multicentre retrospective study of 220 adult patients who underwent allogeneic hematopoietic stem cell transplantation (alloHSCT) for therapy-related acute myeloid leukaemia (t-AML). Median age at t-AML diagnosis was 56 years, with a prior history of haematological (45%) or breast (34%). Median time from cytotoxic exposure to t-AML diagnosis was 54.7 months. At transplant, around 20% of patients had measurable residual disease and 3% of patients were not in complete remission. The median follow-up was 21.4 months (Q1-Q3, 5.9-52.8). At 12 months, overall survival (OS), event-free survival (EFS), and graft-versus-host-disease (GVHD)-free-relapse-free survival (GRFS) were 60.7% (95% CI 54.6-67.5), 52.8% (95% CI 46.5-68.4), and 44.1% (95% CI 37.6-51.8), respectively. At 5 years, OS, EFS, and GRFS were 44.1% (95% CI 37.4-52.1), 40.4% (95% CI 33.9-48.1), and 35.3% (95% CI 28.8-43.3), respectively. At last follow-up, 44% of patients were in complete remission (n = 96) and transplant-related mortality accounted for 21% of all deaths (n = 119). Multivariable analysis revealed that uncontrolled t-AML at transplant was associated with lower EFS (HR 1.94, 95% CI 1.0-3.7, p = 0.041). In conclusion, alloHSCT for t-AML shows encouraging results and offers additional opportunity with the emergence of novel pre-graft therapies.

Pooled allogeneic faecal microbiota MaaT013 for steroid-resistant gastrointestinal acute graft-versus-host disease: a single-arm, multicentre phase 2 trial

Background

Failure of gastrointestinal acute graft-versus-host disease (GI-aGvHD) to respond to steroid therapy is associated with limited further therapeutic options. We aimed to assess the safety and efficacy of the first-in-human use of the pooled allogeneic faecal microbiota, MaaT013, for the treatment of steroid-refractory GI-aGvHD.

Methods

This prospective, international, single-arm, phase 2a study reports clinical outcomes from a 24-patient cohort with grade III-IV, steroid refractory GI-aGvHD treated with the pooled allogeneic faecal microbiota MaaT013. MaaT013 involved pooling faecal matter from 3 to 8 screened donors then transplanting the pooled batches into patients to treat GI-aGVHD. The 24 patients were treated in the HERACLES study (Aug 2018 to Nov 2020) at 26 sites in Europe and an additional 52 patients were treated in a compassionate use/expanded access program (EAP) in France (July 2018 to April 2021). The primary endpoint was GI response at day 28, defined as the proportion of patients with GI-aGvHD who had a complete response (CR) or very good partial response (VGPR). GvHD grading and staging were assessed according to the revised Glucksberg criteria. Adverse events and severe adverse events were monitored for 6 months and 12 months, respectively. The HERACLES study was registered with ClinicalTrials.gov (NCT03359980).

Findings

Compared with single donors, MaaT013 is characterised by higher microbial richness and reduced variability across batches. At day 28 (D28), the GI-overall response rate (ORR) was 38% in the prospective population, including 5 complete responses (CR), 2 very good partial responses (VGPR) and 2 partial responses (PR). In the EAP, the GI-ORR was 58% (17 CR, 9 VGPR and 4 PR). The 12-month overall survival (OS) was 25% in the prospective study and 38% in the EAP. Regarding safety, five infectious complications, including 3 sepsis, could not be excluded from being related to the study procedure in HERACLES. Shotgun sequencing analyses of the identified strains suggest that none were found in MaaT013. In the EAP, 18 pharmacovigilance cases were reported among 52 treated patients, including 11 bacteraemia/sepsis. In HERACLES, we observed in stools from responding patients at D28 a higher microbiota richness and increased levels of beneficial bacteria, in particular butyrate producers, along with increased levels of short-chain fatty acid and bile acids. In contrast, stools from non-responding (NR) patients displayed increased levels of pathogenic pro-inflammatory bacteria along with increased systemic inflammatory parameters.

Interpretation

Overall, MaaT013 was safe in this population of highly immunocompromised patients and was associated with responses in some patients with GI-aGvHD and deserves further investigation.

Funding

MaaT Pharma.

Allogeneic transplantation in advanced cutaneous T-cell lymphomas (CUTALLO): a propensity score matched controlled prospective study

BACKGROUND

Advanced-stage cutaneous T-cell lymphomas (CTCLs) are rare, usually refractory, and fatal diseases. Case series have suggested that allogeneic haematopoietic stem cell transplantation (HSCT) might improve the prognosis of advanced-stage CTCLs. The objective of this study was to investigate the effect of allogeneic HSCT compared with non-HSCT therapy on the outcome of individuals with advanced-stage CTCLs.

METHODS

In this prospective, multicentre, matched controlled trial, conducted at 30 hospitals, participants with advanced CTCLs were allocated treatment: if they had an available compatible related donor they were assigned to allogeneic HSCT, or if not they were allocated to non-allogeneic HSCT therapy. Key inclusion criteria were participants aged 18-70 years, with advanced stage mycosis fungoides or Sézary syndrome, and at least one poor prognostic criteria. Participants were excluded if they were not in complete or partial remission of the disease. Propensity score 1:1 matching with replacement (ie, that each participant treated with HSCT was matched to the participant with the closest propensity score treated with non-HSCT therapy, even if they had already been matched) was used to handle confounding factors, with the balance of covariate distribution between HSCT and non-HSCT groups assessed using standardised mean differences. The primary endpoint was progression-free survival in the matched intention-to-treat population. This trial is registered with ClinicalTrials.gov (NCT02520908), and is currently active but not recruiting.

FINDINGS

From June 1, 2016, to March 3, 2022, total of 99 participants were enrolled at 17 centres in France. Participants with a sibling or matched unrelated donor were assigned to allogeneic HSCT (HSCT group, n=55 [56%]) and participants without a donor were assigned to non-allogeneic HSCT treatment (non-HSCT group, n=44 [44%]). The median follow-up among survivors was 12·6 months (IQR 11·0-35·2). In the HSCT group, 51 participants (93%) were 1:1 matched to participants from the non-HSCT group. In the intention-to-treat analysis, median progression-free survival was significantly longer in the HSCT group (9·0 months [95% CI 6·6-30·5]) than in the non-HSCT group (3·0 months [2·0-6·3]), with a hazard ratio of 0·38 (95% CI 0·21-0·69; p<0·0001). In the per-protocol population, 40 participants (78%) in the HSCT group had 101 serious events and 29 participants (67%) in the non-HSCT group had 70 serious adverse events. The most common serious adverse event other than graft-versus-host disease in both groups was infections, occurring in 30 participants (59%) in the HSCT group and in 19 participants (44%) in the non-HSCT group.

INTERPRETATION

Allogeneic HSCT was associated with significantly longer progression-free survival in participants with advanced-stage CTCLs. These results indicate that allogeneic HSCT treatment should be made available to individuals with high-risk, advanced-stage mycosis fungoides or Sézary syndrome who achieve pre-transplant disease remission.

FUNDING

French Ministry of Health, National Cancer Institute, Programme Hospitalier de Recherche Clinique en Cancérologie.

Efficacy of haematopoietic stem cell boost as a rescue for poor graft function after haematopoietic stem cell transplantation: A multicentre retrospective study on behalf of the Francophone Society for Bone Marrow Transplantation and Cell Therapy (SFGM-TC)

Haematopoietic stem cell reinjection may be a curative option for poor graft function after haematopoietic stem cell transplantation; however, literature supporting its use remains limited. We conducted a multicentre retrospective study on behalf of the Francophone Society of Bone Marrow Transplantation and Cellular Therapy, including 55 patients. We demonstrated response rates of nearly 40% and two-year survival of more than 60% in the context of an otherwise deadly complication and we observed that the timing of injection and the degree of cytopenia are strongly associated with outcomes. This study shows the feasibility of the procedure informing on its epidemiology, outcomes and prognostic factors, setting the stage for future guidelines.

Late relapse after hematopoietic stem cell transplantation for acute leukemia: a retrospective study by SFGM-TC

Late relapse (LR) after allogeneic hematopoietic stem cell transplantation (AHSCT) for acute leukemia is a rare event (nearly 4.5%) and raises the questions of prognosis and outcome after salvage therapy. We performed a retrospective multicentric study between January 1, 2010, and December 31, 2016, using data from the French national retrospective register ProMISe provided by the SFGM-TC (French Society for Bone Marrow Transplantation and Cellular Therapy). We included patients presenting with LR, defined as a relapse occurring at least 2 years after AHSCT. We used the Cox model to identify prognosis factors associated with LR. During the study period, a total of 7582 AHSCTs were performed in 29 centers, and 33.8% of patients relapsed. Among them, 319 (12.4%) were considered to have LR, representing an incidence of 4.2% for the entire cohort. The full dataset was available for 290 patients, including 250 (86.2%) with acute myeloid leukemia and 40 (13.8%) with acute lymphoid leukemia. The median interval from AHSCT to LR was 38.2 months (interquartile range [IQR], 29.2 to 49.7 months), and 27.2% of the patients had extramedullary involvement at LR (17.2% exclusively and 10% associated with medullary involvement). One-third of the patients had persistent full donor chimerism at LR. Median overall survival (OS) after LR was 19.9 months (IQR, 5.6 to 46.4 months). The most common salvage therapy was induction regimen (55.5%), with complete remission (CR) obtained in 50.7% of cases. Ninety-four patients (38.5%) underwent a second AHSCT, with a median OS of 20.4 months (IQR, 7.1 to 49.1 months). Nonrelapse mortality after second AHSCT was 18.2%. The Cox model identified the following factors as associated with delay of LR: disease status not in first CR at first HSCT (odds ratio [OR], 1.31; 95% confidence interval [CI], 1.04 to 1.64; P = .02) and the use of post-transplantation cyclophosphamide (OR, 2.23; 95% CI, 1.21 to 4.14; P = .01). Chronic GVHD appeared to be a protective factor (OR, .64; 95% CI, .42 to .96; P = .04). The prognosis of LR is better than in early relapse, with a median OS after LR of 19.9 months. Salvage therapy associated with a second AHSCT improves outcome and is feasible, without creating excess toxicity.

Outcome after allogeneic stem cell transplantation with haploidentical versus HLA-matched donors in patients with higher-risk MDS

Allogeneic hematopoietic stem cell transplantation remains the best curative option for higher-risk myelodysplastic syndrome. The presence of monosomal karyotype and/or complex karyotype abnormalities predicts inferior survival after allo-SCT in MDS patients. Haploidentical allo-SCT has been increasingly used in acute leukemia (AL) and has similar results as using HLA-matched donors, but data on higher-risk MDS is sparse. We compared outcomes in 266 patients with higher-risk MDS after HLA-matched sibling donor (MSD, n = 79), HLA-matched unrelated donor (MUD, n = 139) and HLA haploidentical donor (HID, n = 48) from 2010 to 2019. Median donor age differed between the three groups (p < 0.001). The overall survival was significantly different between the three groups with a better OS observed in the MUD group (p = 0.014). This observation could be explained by a higher progression-free survival with MUD (p = 0.014). The cumulative incidence of grade 2-4 acute GvHD was significantly higher in the HID group (p = 0.051). However, in multivariable analysis, patients transplanted using an HID had comparable mortality to patients transplanted using a MUD (subdistribution hazard ratio [sHR]: 0.58 [0.32-1.07]; p = 0.080) and a MSD ([sHR]: 0.56 [0.28-1.11]; p = 0.094). MUD do not remain a significant positive predictor of survival, suggesting that beyond the donor-recipient HLA matching, the donor age might impact recipient outcome.

Combining blinatumomab and donor lymphocyte infusion in B-ALL patients relapsing after allogeneic hematopoietic cell transplantation: a study of the SFGM-TC

Relapsed B-cell acute lymphoblastic leukemia (B-ALL) after allogeneic stem cell transplantation (allo-HCT) still represents a major concern with poor outcomes. The aim of this study is to compare the efficacy and safety of blinatumomab and donor lymphocyte infusion (DLI) versus blinatumomab alone in this setting. This is a multicenter retrospective study from centers of SFGM-TC. All transplanted patients who received blinatumomab salvage therapy were included. Patients who received DLI from 1 month before to 100 days after the starting of blinatumomab were included in the blina-DLI group. Seventy-two patients were included. Medium follow-up was 38 months. Fifty received blinatumomab alone and 22 the association blinatumomab-DLI. Two-year overall survival (OS) was 31% in the blinatumomab group and 43% in the blinatumomab-DLI group (p = 0.31). Studying DLI as a time dependent variable, PFS did not significantly differ between the 2 groups (HR:0.7, 95% CI: 0.4-1.5). In multivariate analysis, DLI was not a prognostic factor for OS, progression-free survival and progression/relapse incidence. Adverse events and graft-versus-disease rates were comparable in the 2 groups. In conclusion, adding DLI between 1 month before and 100 days after start of blinatumomab is safe and does not seem to improve outcomes in B-ALL patients who relapsed after allo-HCT.

Pre-exposure prophylaxis with tixagevimab/cilgavimab (AZD7442) prevents severe SARS-CoV-2 infection in recipients of allogeneic hematopoietic stem cell transplantation during the Omicron wave: a multicentric retrospective study of SFGM-TC

Since the emergence of the Omicron variant of SARS-CoV-2, though considered less virulent, hospitalization and death rates among immunocompromised patients remain high, especially for poor responders to vaccination. We conducted a retrospective multicentric study to evaluate pre-exposure prophylaxis with AZD7442 (tixagevimab/cilgavimab) for preventing COVID-19 in adult allogeneic hematopoietic stem cell transplant (allo-HSCT) recipients. Among the 161 patients of our cohort, 22 (14%) contracted COVID-19 after a median follow-up of 105 days, but no severe form was observed. Only one major adverse event was reported: an acute coronary syndrome, resolved without sequelae. Pending randomized controlled trial results, our data support the use of AZD7442 as pre-exposure prophylaxis for COVID-19 during Omicron wave in allo-HSCT patients who failed to develop humoral immunity to vaccination, to prevent severe and potentially lethal forms of SARS-CoV-2 infection.

Radiotherapy or Autologous Stem-Cell Transplantation for Primary CNS Lymphoma in Patients Age 60 Years and Younger: Long-Term Results of the Randomized Phase II PRECIS Study

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported.We previously reported the results of a randomized phase II study in patients with newly diagnosed primary CNS lymphoma (age 18-60 years). Patients were treated with high-dose methotrexate-based induction chemotherapy followed by whole-brain radiotherapy (WBRT) or high-dose chemotherapy (thiotepa-busulfan-cyclophosphamide) with autologous stem-cell transplantation (ASCT). The median follow-up was 33 months. In this report, we provide long-term data (median follow-up, 8 years) regarding the outcomes and toxicities. Fifty-three and 44 patients received induction chemotherapy followed by WBRT or ASCT, respectively. Their 8-year event-free survival from random assignment was 67% and 39% in the ASCT and WBRT arms, respectively (P = .03), with a significantly lower risk of relapse after ASCT (hazard ratio = 0.13, P < .001). One third of patients who relapsed after WBRT were alive after salvage treatment. Five and four patients died of ASCT and WBRT-related toxicities, respectively. The 8-year overall survival was 69% and 65% in the ASCT and WBRT arms, respectively (not significant). Balance (52% v 10%, P ≤ 0.001) and neurocognition (64% v 13%, P < .001) significantly deteriorated after WBRT compared with ASCT during the follow-up. This study shows that 40 Gy WBRT should be avoided in first-line treatment because of its neurotoxicity and suboptimal efficacy in reducing relapses while ASCT appears to be highly efficient in preventing relapses.

Infectious risks in patients treated with extracorporeal photopheresis for graft-versus-host disease: A retrospective cohort study

BACKGROUND

Infections are common with significant mortality and morbidity in patients with graft-versus-host disease (GvHD). Extracorporeal photopheresis (ECP) is an advantageous treatment option for patients with GvHD because it is not immunosuppressive. The objective of this study was to assess the rate of infections and to determine risk factors in patients with GvHD.

MATERIALS AND METHODS

In a single-center cohort, we retrospectively collected data on infectious episodes by evaluating the clinical records of patients with GvHD treated by ECP since 2011.

RESULTS

A total of 47 patients were included in this study. At ECP initiation, there were 10 patients with acute GvHD and 37 with chronic GvHD. At the final follow-up, 200 infectious episodes were diagnosed in 91.5% of patients with an average follow-up of 25.9 months (ie, 1.97 infections per patient per year). Most episodes had positive outcomes as there was no death related to infections, and only six infections required long-term treatment. Higher dose of corticosteroids at the initiation of ECP was significantly associated with a shorter onset of the first infection (hazard ratio [HR] = 2.05; 95% confidence interval [CI] [1.17, 3.57]; P = .013). Unrelated donor transplants were significantly associated with a lower rate of infection (HR = 0.61; 95% CI [0.39, 0.95]; P = .028).

CONCLUSION

The results of our study suggest that ECP is associated with a low infection rate and an optimal clinical efficacy. Thus, ECP is still a suitable treatment for GvHD. Yet, a future study with a larger cohort will be necessary to deepen the identification of risk factors for infection.

Ruxolitinib before allogeneic hematopoietic transplantation in patients with myelofibrosis on behalf SFGM-TC and FIM groups

This multicenter prospective phase 2 trial analyzed disease-free survival (DFS) in myelofibrosis patients receiving ruxolitinib for 6 months before transplantation. Seventy-six patients were recruited. Age-adjusted dynamic international prognostic scoring system was intermediate-1, intermediate-2, and high in 27 (36%), 31 (41%), and 18 (24%) patients. All patients received ruxolitinib from inclusion to conditioning regimen (fludarabine-melphalan) or to progression. A donor was found in 64 patients: 18 HLA-matched sibling donor (MSD), 32 HLA-matched unrelated (UD10/10), and 14 HLA mismatched unrelated donor (UD9/10. Among 64 patients with a donor, 20 (31%) achieved a partial response before transplantation and 59 (92%) could be transplanted after ruxolitinib therapy (18/18 MSD, 30/21 UD10/10, 11/34 UD9/10), of whom 19 (32%) were splenectomized. Overall survival from inclusion was 68% at 12 months. One-year DFS after transplantation was 55%: 83%, 40%, and 34% after MSD, UD10/10 or UD9/10, respectively. Cumulative incidence of grade 2–4 acute graft-versus-host disease (GVHD) was 66% and non-relapse-mortality was 42% at 12 months. Short course of ruxolitinib before transplantation is followed by a high rate of transplantation. With the platform used in this protocol, outcome was much better in patients transplanted with HLA-matched sibling donor as compared to unrelated donor.

Splenectomy before allogeneic hematopoietic cell transplantation for myelofibrosis: A French nationwide study

The value of pretransplant splenectomy in patients with myelofibrosis (MF) is subject to debate, since the procedure may preclude subsequent allogeneic hematopoietic cell transplantation (allo-HCT). To determine the impact of pretransplant splenectomy on the incidence of allo-HCT, we conducted a comprehensive retrospective study of all patients with MF for whom an unrelated donor search had been initiated via the French bone marrow transplantation registry (RFGM) between 1 January 2008 and 1 January 2017. Additional data were collected from the patients' medical files and a database held by the French-Language Society for Bone Marrow Transplantation and Cell Therapy (SFGM-TC). We used a multistate model with four states ("RFGM registration"; "splenectomy"; "death before allo-HCT", and "allo-HCT") to evaluate the association between splenectomy and the incidence of allo-HCT. The study included 530 patients from 57 centers. With a median follow-up time of 6 years, we observed 81 splenectomies, 99 deaths before allo-HCT (90 without splenectomy and nine after), and 333 allo-HCTs (268 without splenectomy and 65 after). In a bivariable analysis, the hazard ratio [95% confidence interval (CI)] for the association of splenectomy with allo-HCT was 7.2 [5.1-10.3] in the first 4 months and 1.18 [0.69-2.03] thereafter. The hazard ratio [95% CI] for death associated with splenectomy was 1.58 [0.79-3.14]. These reassuring results suggest that splenectomy does not preclude allo-HCT in patients with MF.

Medication non-adherence after allogeneic hematopoietic cell transplantation in adult and pediatric recipients: a cross sectional study conducted by the Francophone Society of Bone Marrow Transplantation and Cellular Therapy

Medication non-adherence (NA) after allogeneic hematopoietic cell transplantation (allo-HCT) can lead to serious complications. This study assesses NA in French adult and pediatric recipients and identifies factors associated with NA. In accordance with the EMERGE and STROBE guidelines, a cross sectional multicentric survey was conducted. We used a self-reported questionnaire that was adapted to adults and pediatrics and that could provide a picture of all three phases of medication adherence: initiation, implementation, persistence. We enrolled 242 patients, 203 adults (mean age: 51 years old, 50.7% male) and 39 children (mean age: 9 years old, 56.4% female). Reported NA was estimated at about 75% in both populations, adults and pediatrics. In adults, the univariate analysis showed that patients less than 50 years old (P = 0.041), (i) treated with cyclosporine (P = 0.02), (ii) treated with valacyclovir/acyclovir (P = 0.016), and (iii) experiencing side effects (P = 0.009), were significantly more non-adherent. In multivariate analysis, only recipient age was significantly associated to NA (P = 0.05). The limited size of the pediatric population did not allow us to draw any statistical conclusion about this population. To the best of our knowledge, this is the first study in France on NA in allo-HCT recipients. Our results highlight the age factor as the only factor related to NA. Further studies are needed to confirm our observations and refine results in pediatric populations, currently most at risk of medication NA.

[Indications and management of hematologic microtransplantation: Recommendations of the French Society of Bone Marrow transplantation and cellular Therapy (SFGM-TC)]

Microtransplantation (MT) is based on injection of HLA-mismatched G-CSF mobilized hematopoietic stem cells, in combination with chemotherapy but without use of conditioning regimen nor immunosuppressive drugs. As a result, a transient microchimerism is induced without engraftment. Its efficacy relies both on host immune system stimulation (recipient versus tumor) and on a graft versus tumor effect. Data are scarce and concern mostly Asian patients with acute myeloid leukemia (AML) and high risk myelodysplastic syndrome (HR-MDS). In comparison to conventional treatment without MT, higher complete remission rates and longer disease free survival and overall survival have been reported. Safety seems acceptable. The most frequent adverse event is non-severe cytokine release syndrome. Risk of GVHD remains very low. Here, we summarize the published data and detail the practical aspects of the procedure. Current data are not strong enough to provide recommendations on indications. Nevertheless, it seems reasonable to propose MT to patients with AML or HR-MDS, regardless of age, presenting an indication for allogeneic stem cell transplantation but ineligible for it. MT is still under investigation and rather be proposed within clinical trials.

[Management of CAR-T cell-related encephalopathy syndrome in adult and pediatric patients: Recommendations of the French Society of Bone Marrow transplantation and cellular Therapy (SFGM-TC)]

CAR-T cell-related encephalopathy syndrome (CRES) reflects the potential neurotoxicity of this therapeutic approach and must be considered in the presence of any neurological symptom after the infusion of the CAR-T. This is the second most common adverse event under this therapy and its incidence varies between 12 and 55%. The median time of the onset of the first neurologic symptoms is 4days after CAR-T infusion. The duration of CRES symptoms is generally between 2 and 4days, but late CRES may occur. Monitoring and diagnosis of CERS includes clinical exam, magnetic resonance imaging and electroencephalography. In addition to symptomatic treatments, corticosteroids represent the cornerstone of the high-grade CERS treatment. Drugs targeting IL-6 should be restricted to severe forms, especially those associated with cytokine release syndrome. The purpose of this workshop is to provide practical help in dealing with this complication.

Human herpesvirus 6 infection after autologous stem cell transplantation: A multicenter prospective study in adult patients

OBJECTIVES

to prospectively evaluate the incidence and the clinical relevance on hematopoietic reconstitution of HHV-6 infection in autologous hematopoietic stem cell transplantation (ASCT) recipients.

METHODS

HHV-6 DNA load was measured in whole blood specimens once during the 7 days before stem cell re-infusion and once a week after transplantation until hematopoietic recovery. Active HHV-6 infection was defined by 2 consecutive positive DNA loads.

RESULTS

from July 2012 to February 2015, 196 adult patients undergoing ASCT were enrolled. Twenty-two (11.2%) patients developed active HHV-6 infection with a cumulative incidence of 19% at 40 days after transplantation. The onset of active HHV-6 infection occurred with a median of 13 days after stem cell re-infusion. HHV-6 infection was associated with an increased frequency of non-infectious complications (OR = 5.05; 95%CI 1.78-14.32; P < 0.001). Moreover, the severity of these non-infectious complications was higher in recipients exhibiting HHV-6 infection (OR = 4.62; 95%CI 1.32-16.2; p < 0.01). Delayed neutrophils 10 (IQR: 8-14) vs 8 (IQR: 6-11) days and platelets recoveries 15 (IQR: 11.8-18.5) vs 8 (IQR: 4-14) days were observed in patients with active HHV-6 infection compared to non-infected ones.

CONCLUSIONS

in this study, 11.2% ASCT recipients presented active HHV-6 infection associated with significantly delayed hematologic reconstitution.

Radiotherapy or Autologous Stem-Cell Transplantation for Primary CNS Lymphoma in Patients 60 Years of Age and Younger: Results of the Intergroup ANOCEF-GOELAMS Randomized Phase II PRECIS Study

PURPOSE

To determine the efficacy and toxicity of chemoimmunotherapy followed by either whole-brain radiotherapy (WBRT) or intensive chemotherapy and autologous stem-cell transplantation (ASCT) as a first-line treatment of primary CNS lymphoma (PCNSL).

PATIENTS AND METHODS

Immunocompetent patients (18 to 60 years of age) with untreated PCNSL were randomly assigned to receive WBRT or ASCT as consolidation treatment after induction chemotherapy consisting of two cycles of R-MBVP (rituximab 375 mg/m2 day (D) 1, methotrexate 3 g/m2 D1; D15, VP16 100 mg/m2 D2, BCNU 100 mg/m2 D3, prednisone 60 mg/kg/d D1-D5) followed by two cycles of R-AraC (rituximab 375 mg/m2 D1, cytarabine 3 g/m2 D1 to D2). Intensive chemotherapy consisted of thiotepa (250 mg/m2/d D9; D8; D7), busulfan (8 mg/kg D6 through D4), and cyclophosphamide (60 mg/kg/d D3; D2). WBRT delivered 40 Gy (2 Gy/fraction). The primary end point was 2-year progression-free survival. Cognitive outcome was the main secondary end point. Analysis was intention to treat in a noncomparative phase II trial.

RESULTS

Between October 2008 and February 2014, 140 patients were recruited from 23 French centers. Both WBRT and ASCT met the predetermined threshold (among the first 38 patients in each group, at least 24 patients were alive and disease free at 2 years). The 2-year progression-free survival rates were 63% (95% CI, 49% to 81%) and 87% (95% CI, 77% to 98%) in the WBRT and ASCT arms, respectively. Toxicity deaths were recorded in one and five patients after WBRT and ASCT, respectively. Cognitive impairment was observed after WBRT, whereas cognitive functions were preserved or improved after ASCT.

CONCLUSION

WBRT and ASCT are effective consolidation treatments for patients with PCNSL who are 60 years of age and younger. The efficacy end points tended to favor the ASCT arm. The specific risk of each procedure should be considered.

[Management of cytokine release syndrome in adult and pediatric patients undergoing CAR-T cell therapy for hematological malignancies: Recommendation of the French Society of Bone Marrow and cellular Therapy (SFGM-TC)]

The cytokine release syndrome (CRS) is the most common complication after adoptive immunotherapies such as chimeric antigen receptor T cells (CAR-T). The incidence varies from 30 to 100% depending on the CAR-T construct, cell doses and the underlying disease. Severe cases may involve 10 to 30% of patients. The triggering event is the activation of the CAR-T, after meeting with their target. The T cell activation leads to the release of effector cytokines, such as IFNγ, TNFα and IL2, that are responsible for the activating of monocyte/macrophage system, resulting in the production of pro-inflammatory cytokines, (including IL6, IFN-γ, IL10, MCP1) and associated with a significant elevation of CRP and ferritin. The CRS usually appears between 1 and 14days after the infusion of the cells and can last from 1 to 10days. Rare fatal cases have been reported in the literature. The first symptom is often a fever, sometimes very high, which must alert and reinforce the surveillance. In moderate forms, one can find fatigue, headache, rash, arthralgia and myalgia. T cell-related encephalopathy (CRES) syndrome may occur concomitantly. In case of aggravation, a vasoplegic shock associating capillary leakage and respiratory distress can occur. Close clinical monitoring is essential right from the injection to quickly detect the first symptoms. The treatment of severe forms, in addition to symptomatic management involves monoclonal antibodies targeting the IL6 or IL6 receptor, and sometimes steroids. Close cooperation with intensive care units is essential since 20 to 50% of patients require intensive care unit transfer.

[Harmonization of data coding in post-transplant follow-up - "GVHD, complications and additional treatments": Guidelines from the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC)]

The quality of the information provided in post-transplant follow-up is necessary to obtain a coherent and exploitable database. Since the beginning of 2017, three forms (Med-B-allograft) have been available: the first month (Day 0), Day 100 (second report) and an annual follow-up report. Recommendations for follow-up were addressed in the 2014 harmonization workshop, "Harmonization of Data Coding…". However, it is sometimes difficult to determine which data to specify in ProMISe for post-transplantation. The objective of this workshop was to clarify certain situations and/or items.

Scoring System Based on Post-Transplant Complications in Patients after Allogeneic Hematopoietic Cell Transplantation for Myelodysplastic Syndrome: A Study from the SFGM-TC

PURPOSE

We developed a prognostic scoring system to evaluate the prognosis of myelodysplastic syndrome (MDS) patients surviving more than 100 days allogeneic hematopoietic cell transplantation after (allo-HCT).

PATIENTS AND METHODS

We performed a landmark analysis on a derivation cohort of 393 cases to identify prognostic factors for 3-year overall survival. Potential predictor variables included demographic and clinical data, transplantation modalities and early post-transplant complications. The scoring system was tested against a validation cohort which included 391 patients.

RESULTS

Complications occurring before day 100 such as relapse [HR = 6.7; 95%CI, 4.5-10.0] (4 points), lack of platelet recovery [HR, 3.6; 95%CI, 2.2-5.8] (2 points), grade-II acute GVHD [HR = 1.7; 95%CI, 1.2-2.5] (1 point) and grade-III/IV [HR = 2.6; 95%CI, 1.8 -3.8] (2 points) were the only independent predictors of 3-year OS. The 3-year OS associated with low (0), intermediate (1-3) and high (≥4) risk scores was respectively 70%, 46% and 6%. The model performed consistently in both cohorts, with good calibration.

CONCLUSION

This post-transplant scoring system is a powerful predictor of outcome after allo-HCT for MDS, and can provide useful guidance for clinicians. Additional studies are required to evaluate this scoring system for other hematologic malignancies.

Clonal evolution of myelofibrosis treated with hematopoietic transplantation, using RUXOLITINIB for chronic GvHD: A case report

Deciphering the mutational patterns and/or the biomarkers that might predict clinical response in patients with myelofibrosis is primordial to make treatment decisions. In this report, we discuss the clinical history, pathological evaluation, and genomics findings in a patient with JAK2-positive myelofibrosis who developed a secondary myelodysplasia after hematopoietic stem cell transplantation and JAK1/2 inhibitor treatment. Using next-generation sequencing, a paired comparison of relapse-specific versus primary tumour mutations highlighted the dynamic clonal evolution at relapse, showing concurrently the complete eradication of the JAK2-positive clone and the expansion of a second JAK2-negative clone with additional mutations. Importantly, another unexpected finding was that myelodysplasia was not secondary to allogeneic transplantation as relapse was driven by the overgrowth of a preexisting mutated clone, probably fostered by initial treatment options. This case underlines the fact that determining the genetic changes associated with the primary disease and its evolution is crucial to accurately correlate variants frequency to treatment decision and/or treatment response.

Cytotect®CP as salvage therapy in patients with CMV infection following allogeneic hematopoietic cell transplantation: a multicenter retrospective study

Cytomegalovirus is one of the main contributing factors to high mortality rates in patients undergoing allogeneic hematopoietic cell transplantation (allo-HCT). The main factors of treatment failure are both drug resistance and intolerance. In some cases, Cytotect®CP CMV-hyperimmune globulin is used as salvage therapy. This study aims to investigate the safety and efficacy of Cytotect®CP as a salvage therapy in patients with CMV infection after allo-HCT. Twenty-three consecutive patients received Cytotect®CP for CMV infection after prior CMV therapy. At the time of Cytotect®CP introduction, 17 patients (74%) had developed acute GVHD and 15 patients (64%) were receiving steroid treatment; Cytotect®CP was used as monotherapy (n = 7) and in combination (n = 16). Overall, response was observed in 18 patients (78%) with a median time of 15 days (range: 3-51). Of the 18 responders, 4 experienced CMV reactivation, while 5 responders died within 100 days of beginning treatment. Of these 5 deaths, 4 were due to causes unrelated to CMV. Estimated 100-day OS from the introduction of Cytotect®CP was 69.6%. No statistically significant difference was observed in 100-day OS between responders and non-responders (73.7% vs 50.0%, p = 0.258). Cytotect®CP as salvage therapy is effective and well-tolerated. Given its safety profile, early treatment use should be considered.

Similar outcome of allogeneic stem cell transplantation after myeloablative and sequential conditioning regimen in patients with refractory or relapsed acute myeloid leukemia: A study from the Société Francophone de Greffe de Moelle et de Thérapie Cellulaire

Patients with acute myeloid leukemia (AML) in relapse or refractory to induction therapy have a dismal prognosis. Allogeneic hematopoietic stem cell transplantation is the only curative option. In these patients, we aimed to compare the results of a myeloablative transplant versus a sequential approach consisting in a cytoreductive chemotherapy followed by a reduced intensity conditioning regimen and prophylactic donor lymphocytes infusions. We retrospectively analyzed 99 patients aged 18-50 years, transplanted for a refractory (52%) or a relapsed AML not in remission (48%). Fifty-eight patients received a sequential approach and 41 patients a myeloablative conditioning regimen. Only 6 patients received prophylactic donor lymphocytes infusions. With a median follow-up of 48 months, 2-year overall survival was 39%, 95% confidence interval (CI) (24-53) in the myeloablative group versus 33%, 95% CI (21-45) in the sequential groups (P = .39), and 2-year cumulative incidence of relapse (CIR) was 57% versus 50% respectively (P = .99). Nonrelapse mortality was not higher in the myeloablative group (17% versus 15%, P = .44). In multivariate analysis, overall survival, CIR and nonrelapse mortality remained similar between the two groups. However, in multivariate analysis, sequential conditioning led to fewer acute grade II-IV graft versus host disease (GVHD) (HR for sequential approach = 0.37; 95% CI: 0.21-0.65; P < .001) without a significant impact on chronic GVHD (all grades and extensive). In young patients with refractory or relapsed AML, myeloablative transplant and sequential approach offer similar outcomes except for a lower incidence of acute GvHD after a sequential transplant.

[Allogeneic haematopoietic cell transplantation for diffuse large B cell lymphoma: Guidelines from the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC)]

Despite great improvements in the outcome of patients with lymphoma, some may still relapse or present with primary refractory disease. In these situations, allogeneic hematopoietic cell transplantation is a potentially curative option, this is true particularly in the case of after autologous stem cell transplantation if remission can be achieved. Recently, novel agents such as anti-PD1 and BTK inhibitors have started to challenge the use of allogeneic hematopoietic cell transplantation for relapsed or refractory lymphoma. During the 2016 annual workshop of the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC), we performed a comprehensive review of the literature published in the last 10 years and established guidelines to clarify the indications and transplant modalities in this setting. This section specifically reports on our conclusions regarding diffuse large B cell lymphoma.

[Allogeneic haematopoietic cell transplantation for indolent lymphomas: Guidelines from the Francophone Society Bone Marrow Transplantation and Cellular Therapy (SFGM-TC)]

Despite great improvements in the outcome of patients with lymphoma, some may still relapse or present with primary refractory disease. In these situations, allogeneic hematopoietic cell transplantation is a potentially curative option, this is true particularly the case of relapse after autologous stem cell transplantation. Recently, novel agents such as anti-PD1 and BTK inhibitors have started to challenge the use of allogeneic hematopoietic cell transplantation for relapsed or refractory lymphoma. During the 2016 annual workshop of the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC), we performed a comprehensive review of the literature published in the last 10 years and established guidelines to clarify the indications and transplant modalities in this setting. This paper specifically reports on our conclusions regarding indolent lymphomas, mainly follicular lymphoma and chronic lymphocytic leukemia.

[Use of alternative donors for allogeneic haematopoietic cell transplantation in lymphoid neoplasms: Guidelines from the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC)]

Despite great improvements in the outcome of patients with lymphoma, some may still relapse or present with primary refractory disease. In these situations, allogeneic haematopoietic cell transplantation (allo-HCT) is a potentially curative option, in particular in the case of relapse after autologous stem cell transplantation. Recently, novel agents such as anti-PD1 and BTK inhibitors have started to challenge the use of allo-HCT for relapsed or refractory lymphoma. During the 2016 annual workshop of the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC), we performed a comprehensive review of the literature published in the last 10 years and established guidelines to clarify the indications and transplant modalities in this setting. This manuscript reports on general considerations regarding allo-HCT for lymphoma and elaborates on the use of alternative donors in this setting.

Clinical impact of NK-cell reconstitution after reduced intensity conditioned unrelated cord blood transplantation in patients with acute myeloid leukemia: analysis of a prospective phase II multicenter trial on behalf of the Société Française de Greffe de Moelle Osseuse et Thérapie Cellulaire and Eurocord

Unrelated cord blood transplantation (UCBT) after a reduced intensity conditioning regimen (RIC) has extended the use of UCB in elderly patients and those with co-morbidities without an HLA-identical donor, although post-transplant relapse remains a concern in high-risk acute myeloid leukemia (AML) patients. HLA incompatibilities between donor and recipient might enhance the alloreactivity of natural killer (NK) cells after allogeneic hematopoietic stem-cell transplantation (HSCT). We studied the reconstitution of NK cells and KIR-L mismatch in 54 patients who underwent a RIC-UCBT for AML in CR in a prospective phase II clinical trial. After RIC-UCBT, NK cells displayed phenotypic features of both activation and immaturity. Restoration of their polyfunctional capacities depended on the timing of their acquisition of phenotypic markers of maturity. The incidence of treatment-related mortality (TRM) was correlated with low CD16 expression (P=0.043) and high HLA-DR expression (P=0.0008), whereas overall survival was associated with increased frequency of NK-cell degranulation (P=0.001). These features reflect a general impairment of the NK licensing process in HLA-mismatched HSCT and may aid the development of future strategies for selecting optimal UCB units and enhancing immune recovery.

Impact of fluconazole versus posaconazole prophylaxis on the incidence of fungal infections in patients receiving induction chemotherapy for acute myeloid leukemia

BACKGROUND

Invasive fungal infections (IFIs) remain one of the worrying complications in patients with acute myeloid leukemia (AML) due to their incidence and high level of attributable mortality. In light of these risks, antifungal prophylaxis has always been debated. We conducted a single-center retrospective study of two prophylactic antifungal agents (fluconazole/posaconazole) in 91 consecutive patients receiving induction chemotherapy for AML between 2005 and 2009, in order to evaluate the impact on the incidence of IFI and on the mycological flora of the patients.

METHODS

In total, 39 patients received prophylactic fluconazole versus 52 who received posaconazole. The baseline characteristics of the two groups were comparable.

RESULTS

Overall, 17 patients developed an IFI, with no difference in frequency between the two groups. Utilization of empirical or pre-emptive therapy was similar irrespective of the type of prophylaxis used. Mycological examination of stools revealed an increase in non-albicans Candida colonization in the fluconazole group during hospitalization and the appearance of Saccharomyces cerevisiae colonization in patients receiving posaconazole.

CONCLUSION

The present study does not distinguish between fluconazole and posaconazole as a primary effective prevention against fungal infections. More prospective studies and meta-analyses are warranted.

A phase 1/2 trial of lenalidomide and dexamethasone in adult patients with refractory/relapsed acute lymphoblastic leukemia

OBJECTIVES

Adult patients with refractory/relapsed ALL have poor survival outcomes with current chemotherapies. We aimed to determine safety and efficacy of lenalidomide, an oral immunomodulator, in these patients.

METHODS

This phase 1/2 trial (EUDRACT # 2009-009372-13) included 10 patients who received 28-day cycles of oral lenalidomide 25 mg/day, days 1 through 21, in combination with oral dexamethasone 40 mg/day on days 1, 8, 15, 22. Primary endpoints were tolerance and the overall response rate (ORR). Secondary endpoints included overall survival (OS) and quality of life.

RESULTS

The most common grade 3 or 4 adverse events were myelosuppression. The ORR among the participants who could be evaluated was 28.6% (95% confidence interval [CI], 0-62.2%). The median OS was 92 days (range, 43-133 days). All patients have died because of progressive disease. Quality of life remains stable during treatment cycles.

DISCUSSION AND CONCLUSION

The safety of combination therapy consisting of lenalidomide plus dexamethasone is consistent with ambulatory administration. Efficacy should be reevaluated in a larger series including patients less intensively previously treated.

Impact of ATG Dose on the Outcome of Patients Undergoing Reduced Intensity Conditioning Followed by Allogeneic Hematopoietic Stem Cell Transplantation for Hematological Malignancies

Reduced intensity conditioning for allogeneic hematopoietic stem cell transplantation (allo-HSCT) is often proposed for patients with comorbidities. To enhance engraftment and limit graft-versus-host disease (GVHD), antithymoglobulin (ATG) is usually used. However, the dose needed remains unclear unlike myeloablative conditioning. In order to clarify this point, we conducted a retrospective study on patients who received a reduced intensity conditioning allo-HSCT based on a 2-day fludarabine and busulfan treatment with either 1 or 2 days of ATG treatment. One hundred and eight patients received 2.5 mg/kg (ATG2.5) and another 60 patients 5 mg/kg (ATG5). The median follow-up was 36 months. The median overall survival was 39 months and the median disease-free survival 45 months. In multivariate analysis, overall nonrelapse mortality (NRM) was independently influenced by the acute GVHD grade III-IV (p < 0.001) and ATG dose (30 vs. 21% for ATG5; p = 0.008). Despite heterogeneity of populations, using proportional-hazard assumptions, we have been able to observe in multivariate analysis a lower NRM in the ATG5 group. This leads to a statistically higher overall survival for the ATG5 group. In conclusion, 2 days of ATG decrease NRM independently without increasing the risk of relapse or infectious disease.

Allogeneic stem cell transplantation for patients with mantle cell lymphoma who failed autologous stem cell transplantation: a national survey of the SFGM-TC

Poly-chemotherapy plus rituximab followed by autologous stem cell transplantation (auto-SCT) is standard care for untreated young patients with mantle cell lymphoma (MCL). Despite this intensive treatment, transplant patients remain highly susceptible to relapse over time. The French SFGM-TC performed a national survey on reduced-intensity conditioning allogeneic stem cell transplantation (RIC-allo-SCT) for fit relapsed/refractory patients who failed after auto-SCT (n=106). Median times of relapse after auto-SCT, and from auto-SCT to RIC-allo-SCT were 28 months and 3.6 years, respectively. Sixty per cent of patients received at least three lines of treatment before RIC-allo-SCT. Conditioning regimens for RIC-allo-SCT were heterogeneous. Twenty patients experienced grade III/IV aGvHD, extensive cGvHD was reported in 28 cases. Median follow-up after RIC-allo-SCT was 45 months. Median PFS after RIC-allo-SCT was 30.1 months and median overall survival was 62 months. Treatment-related mortality (TRM) at 1 year and 3 years were estimated at 28% and 32%, respectively. A total of 52 patients died; major causes of death were related to toxicity (n=34) and MCL (n=11). Patients in good response before RIC-allo-SCT experienced a better PFS and OS. Our work highlights the need for new RIC-allo-SCT MCL-tailored approaches to reduce TRM, and early and late relapse.

Management of Myelodysplastic Syndrome Relapsing after Allogeneic Hematopoietic Stem Cell Transplantation: A Study by the French Society of Bone Marrow Transplantation and Cell Therapies

To find out prognostic factors and to investigate different therapeutic approaches, we report on 147 consecutive patients who relapsed after allogeneic hematopoietic stem cell transplantation (allo-HSCT) for myelodysplastic syndrome (MDS). Sixty-two patients underwent immunotherapy (IT group, second allo-HSCT or donor lymphocyte infusion), 39 received cytoreductive treatment alone (CRT group) and 46 were managed with palliative/supportive cares (PSC group). Two-year rates of overall survival (OS) were 32%, 6%, and 2% in the IT, CRT, and PSC groups, respectively (P < .001). In multivariate analysis, 4 factors adversely influenced 2-year rates of OS: history of acute graft-versus-host disease (hazard ratio [HR], 1.83; 95% confidence interval [CI], 1.26 to 2.67; P = .002), relapse within 6 months (HR, 2.69; 95% CI, .82 to 3.98; P < .001), progression to acute myeloid leukemia (HR, 2.59; 95% CI, 1.75 to 3.83; P < .001), and platelet count < 50 G/L at relapse (HR, 1.68; 95% CI, 1.15 to 2.44; P = .007). A prognostic score based on those factors discriminated 2 risk groups with median OSs of 13.2 versus 2.4 months, respectively (P < .001). When propensity score, prognostic score, and treatment strategy were included in Cox model, immunotherapy was found to be an independent factor that favorably impacts OS (HR, .40; 95% CI, .26 to .63; P < .001). In conclusion, immunotherapy should be considered when possible for MDS patients relapsing after allo-HSCT.