High Torque teno virus load and outcome of patients undergoing allogeneic hematopoietic cell transplantation.

Quantification of Torque teno virus (TTV) load emerged as a marker of immunosuppression. Associations of TTV load with complications and survival after allogeneic hematopoietic cell transplantation (allo-HCT) were controversial in published studies. In this prospective study, we aimed to identify factors influencing TTV load after allo-HCT and to determine whether the TTV load is associated with complications or outcomes. Seventy allo-HCT recipients were included. TTV DNA load was quantified in 469 plasma samples of 70 patients from Day (D) 15 before D120 after transplantation. The influence of transplant characteristics on TTV load and the associations of TTV load with viral infections, acute graft versus host disease, mortality, and relapse were analyzed. More than 80% of patients were TTV DNA positive from D30 after transplantation onwards. Median TTV load increased between D30 and D60 post-transplantation. Patients with lymphoid malignancies had higher TTV load than those with myeloid malignancies. Myeloablative conditioning was associated with higher TTV loads. Patients with no measurable residual disease at transplant had higher TTV loads. High TTV load at D90 post-transplantation was associated with lower overall survival and at D120 post-transplantation was associated with higher relapse rate. In conclusion, TTV load at time points later than D90 after allo-HCT may be useful to assess prognosis.

Single-agent 5-azacytidine as post-transplant maintenance in high-risk myeloid malignancies undergoing allogeneic hematopoietic cell transplantation.

Relapse is a major cause of treatment failure after allogeneic hematopoietic cell transplantation (allo-HCT) in myeloid malignancies. Additional strategies have been devised to further maximize the immunologic effect of allo-HCT, notably through maintenance therapy with hypomethylating agents such as 5-azacytidine (AZA). We conducted a single-center retrospective study to investigate the efficacy of AZA after allo-HCT for high-risk myeloid malignancies. All patients transplanted between Jan 2014 and Sept 2019 for high-risk acute myeloid leukemia (n = 123), myelodysplastic syndrome (n = 51), or chronic myelomonocytic leukemia (n = 11) were included. Patients who died, relapsed, or developed grade ≥ 2 acute graft-versus-host disease before day + 60 were excluded, as well as those who were eligible for anti-FMS-like tyrosine kinase 3 maintenance. Of the 185 included patients, 65 received AZA while 120 did not. Median age at transplant was 59 years; 51.9% of patients were males. The median follow-up was 24 months for both groups. Regarding main patient characteristics and transplantation modalities, the two groups were comparable. In multivariate analyses, there were no significant differences between the two groups in terms of 2-year cumulative incidence of relapse (HR = 1.19; 95% confidence interval (CI) 0.67-2.12; p = 0.55), overall survival (HR = 0.62; 95%CI 0.35-1.12; p = 0.12) and event-free survival (HR = 0.97; 95%CI 0.60-1.58; p = 0.91) rates. In conclusion, single-agent AZA does not appear to be an optimal drug for preventing post-transplant relapse in patients with high-risk myeloid malignancies. This study highlights the need for prospective studies of alternative therapies or combination approaches in the post-transplant setting.

Impact of Defibrotide in the Prevention of Acute Graft-Versus-Host Disease Following Allogeneic Hematopoietic Cell Transplantation.

BACKGROUND: Defibrotide is indicated for patients who develop severe sinusoidal obstructive syndrome following allogeneic hematopoietic cell transplantation (allo-HCT). Preclinical data suggested that defibrotide carries a prophylactic effect against acute graft-versus-host disease (aGVHD). OBJECTIVE: The purpose of this study was to investigate the effect of defibrotide on the incidence and severity of aGVHD. METHODS: This single-center retrospective study included all consecutive transplanted patients between January 2014 and December 2018. A propensity score based on 10 predefined confounders was used to estimate the effect of defibrotide on aGVHD via inverse probability of treatment weighting (IPTW). RESULTS: Of the 482 included patients, 64 received defibrotide (defibrotide group) and 418 did not (control group). Regarding main patient characteristics and transplantation modalities, the two groups were comparable, except for a predominance of men in the defibrotide group. The median age was 55 years (interquartile range [IQR]: 40-62). Patients received allo-HCT from HLA-matched related donor (28.6%), HLA-matched unrelated donor (50.8%), haplo-identical donor (13.4%), or mismatched unrelated donor (7.0%). Stem cell source was either bone marrow (49.6%) or peripheral blood (50.4%). After using IPTW, exposure to defibrotide was not significantly associated with occurrence of aGVHD (HR = 0.97; 95% CI 0.62-1.52; P = .9) or occurrence of severe aGVHD (HR = 1.89, 95% CI: 0.98-3.66; P = .058). CONCLUSION AND RELEVANCE: Defibrotide does not seem to have a protective effect on aGVHD in patients undergoing allo-HCT. Based on what has been reported to date and on these results, defibrotide should not be considered for the prevention of aGVHD outside clinical trials.

Diverting Enterostomy Improves Overall Survival of Patients With Severe Steroid-refractory Gastrointestinal Acute Graft-Versus-Host Disease.

OBJECTIVE: The aim of this study was to evaluate the benefit of diverting enterostomy (DE) in patients with severe steroid-refractory (SR) gastrointestinal acute graft-versus-host-disease (GI-aGVHD) following allogeneic hematopoietic stem-cell transplantation (ASCT). SUMMARY AND BACKGROUND DATA: Severe GI-aGVHD refractory to the first-line steroid therapy is a rare but dramatic life-threatening complication. Second lines of immunosuppressors have limited effects and increase the risk of sepsis. Data suggest that limiting GI bacterial translocation by DE could restrain severe GI-aGVHD. METHODS: From 2004 to 2018, we retrospectively reviewed all consecutive patients undergoing ASCT for hematologic malignancies who developed severe SR GI-aGVHD. We compared patients in whom a proximal DE was performed (Enterostomy group) with those not subjected to DE (Medical group). The primary endpoint was the 1-year overall survival (OS) measured from the onset of GI-aGVHD. Secondary endpoints were the 2-year OS and causes of death. RESULTS: Of the 1295 patients who underwent ASCT, 51 patients with severe SR GI-aGVHD were analyzed (13 in Enterostomy group and 38 in Medical group). Characteristics of patients, transplantation modalities, and aGVHD severity were similar in both groups. The 1-year OS was better after DE (54% vs 5%, P = 0.0004). The 2-year OS was also better in "Enterostomy group" (31% vs 2.5%; P = 0.0015), with a trend to lower death by sepsis (30.8% vs 57.9%; P = 0.091). CONCLUSION: DE should be considered for severe GI-aGVHD as soon as resistance to the corticosteroid is identified.

Rituximab-based first-line treatment of cGVHD after allogeneic SCT: results of a phase 2 study.

Chronic graft-versus-host disease (cGVHD) is the main cause of late nonrelapse mortality and morbidity after allogeneic stem cell transplantation (allo-SCT). To improve such patients' outcomes, we conducted a phase 2, prospective, multicenter trial to test the efficacy of the addition of rituximab to corticosteroids (CSs) and cyclosporine A (CsA) as first-line therapy for newly diagnosed cGVHD after allo-SCT. Twenty-four patients (median age, 47 years) with mild (n = 2), moderate (n = 7), or severe (n = 15) cGVHD were included. All patients received rituximab 375 mg/m2 weekly for 4 weeks, followed by a second course 1 month later for patients with partial response. Twenty of 24 patients (83%) were in response at 1 year. Furthermore, among 19 evaluable patients, 14 (74%) were off CSs. The estimated 1-year overall survival was 83%, and the 1-year cumulative incidence of nonrelapse mortality was 14%. One patient died of progressive multifocal leukoencephalopathy. Although PD-L1hi naive B cells were significantly decreased at diagnosis of cGVHD, they increased after anti-CD20 B-cell depletion. In contrast, activated ICOShi PD-1hi circulating T follicular helper (Tfh) cells decreased after rituximab treatment. Overall, the addition of rituximab to corticosteroid and CsA appeared to be safe and effective for first-line treatment of cGVHD. Furthermore, our data suggest that this efficacy may be in part related to an effect on PD-L1hi B cells and Tfh cells. This study was registered at www.clinicaltrials.gov as identifier NCT01135641.

Association Between Low Plasma Level of Citrulline Before Allogeneic Hematopoietic Cell Transplantation and Severe Gastrointestinal Graft vs Host Disease.

BACKGROUND & AIMS: The gastrointestinal form of acute graft vs host disease increases morbidity and mortality following allogeneic hematopoietic cell transplantation. Plasma levels of citrulline, a non-proteinogenic amino acid, indicate functional enterocyte mass. We measured citrulline in patients before allogeneic hematopoietic cell transplantation and investigated its association with incidence and severity of gastrointestinal graft vs host disease. METHODS: We performed a retrospective study with 191 patients (69 women, 122 men; median age of 52 years) who underwent allogeneic hematopoietic cell transplantation for hematological malignancies at a tertiary center of France from January 2013 through April 2015. Levels of citrulline in plasma samples collected 30 days before graft infusion were measured by high performance liquid chromatography with tandem mass spectrometry. We assigned patients to groups with a high level of citrulline (>26 µmol/L) or low level of citrulline (≤26 µmol/L). The primary outcomes were difference between groups in incidence of stage 2-4 gastrointestinal graft vs host disease, death without hematological disease relapse (non-relapse mortality), relapse of the hematological disease, and overall survival through 2 years after transplantation. RESULTS: Ninety-six patients (50%) developed acute graft vs host disease and 37 (19%) developed a gastrointestinal form. Among patients with gastrointestinal involvement, 33 patients (89%) had stage 2-4 gastrointestinal graft vs host disease. In univariable analysis, low level of citrulline associated with higher cumulative incidence of stage 2-4 gastrointestinal graft vs host disease, non-relapse mortality, and shorter overall survival. In multivariable analysis, low level of citrulline was the only risk factor independently associated with stage 2-4 gastrointestinal graft vs host disease (hazard ratio, 3.06; 95% CI, 1.37-6.85; P = .007); it also associated with increased non-relapse mortality (hazard ratio, 2.29; 95% CI, 1.24-4.22; P = .008). CONCLUSIONS: In a retrospective study with 191 patients, we associated a low plasma level of citrulline before allogeneic hematopoietic cell transplantation with a higher risk for stage 2-4 gastrointestinal graft vs host disease and non-relapse mortality. This marker might be used to manage patients before allogeneic hematopoietic cell transplantation.

[Allogeneic hematopoietic stem cell transplantation and treatment with CAR-T cells - identification of psycho-social vulnerability factors: Guidelines from the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC)]. / Allogreffe de cellules souches hématopoïétiques et traitement par CAR-T cells ­ repérage des facteurs de vulnérabilité psycho-sociale : recommandations de la Société francophone de greffe de moelle et de thérapie cellulaire (SFGM-TC).

Allogeneic hematopoietic stem cell transplantation (HCT) and CAR-T cells therapy are treatments with curative aim for certain hematological malignancies, refractory or relapse. Nevertheless, they carry the risk of morbidity and mortality and may have a significant psychosocial impact, particularly for HCT. It is therefore necessary to identify psychological difficulties and social problems, as well as the patient's resources, and those of his entourage, in order to improve his overall management. The objective of this evaluation is not to pose contraindications to treatments, but to adapt the personalized care project. This identification must be carried out early on in the pre-HCT assessment journey to enable the implementation of appropriate actions by the various care providers. Based on a review of the literature, we designed a psychosocial data collection grid that can be initiated in pre-transplant and updated by accompanying the patient at each stage of follow-up (discharge from hospital, day-hospital follow-up, D100 evaluation). This grid is divided into 3 axes: socio-family context, psychological and somatic aspects. This tool allows the traceability of the interventions of different professionals and is a support for multidisciplinary exchanges.

[Fertility preservation and hematopoietic stem cell transplantation (SFGM-TC)]. / Fertilité et greffe de cellules souches hématopoïétiques (SFGM-TC).

Conditioning regimen prior to hematopoietic stem cell transplantation have an impact on patient fertility through the use of gonadal irradiation and/or bifunctional alkylating agents. Their impact on fertility depends mainly on the dose used and, in women, on age at the time of treatment. All patients should benefit before treatment from a consultation informing them of the potential impact on fertility and of fertility preservation techniques. In the absence of contraindications, the major toxicity of myeloablative conditioning regimen justifies fertility preservation. There are few data concerning fertility after reduced-intensity conditioning. Despite lower theoretical gonadotoxicity, we also recommend fertility preservation, if possible before transplantation. The fertility preservation techniques used depend on the patient's age, pathology and conditioning. In the event of subsequent use of harvested gonadal tissue in the context of acute leukemia or aggressive lymphoma, it is advisable to assess the risk of reintroduction of tumor cells. Finally, it is recommended to assess gonadal function after transplant, especially after reduced conditioning. If there is persistent residual gonadal function, post-treatment fertility preservation should be discuss.

[Update for cord blood unit selection in hematopoietic stem cell transplantation (workshop SFGM-TC)]. / Mise à jour des recommandations pour le choix des unités de sang placentaire en greffe de cellules souches hématopoïétiques (atelier SFGM-TC).

Changing practices and the limited use of cord blood units as a source of cells for allogeneic hematopoietic stem cell transplants (HSC) led us to reconsider the recommendations established in 2011 and 2012, and to propose an update incorporating recent bibliographic data. If HLA compatibility was until now established at low resolution for HLA-A and B loci, and at high resolution for HLA-DRB1, the recent papers are converging towards an increase in the level of resolution, making way for a compatibility now defined in high resolution for all the considered loci, and the inclusion of the HLA-C locus, in order to establish a level of HLA compatibility on 8 alleles (HLA-A, B, C and DRB1). The CD34+ dose is a determining factor in hematopoietic reconstitution but it is not correlated with the total nucleated cells content. This is why we recommend taking these two data into account when choosing a cord blood unit. The recommendations established by our group are presented as a flow chart taking into account the characteristics of the underlying pathology (malignant or non-malignant), the cell dose and the HLA compatibility criteria, as well as criteria linked to the banks in which units are stored.

[Hematological toxicities post-CAR-T cells: Recommendations of the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC)]. / Toxicités hématologiques après CAR-T cells, recommandations de la Société francophone de greffe de moelle et de thérapie cellulaire (SFGM-TC).

Chimeric antigen receptor T cell (CAR-T cell) therapy has become a standard-of-care for several hematological and a promising treatment for solid malignancies or for selected non-malignant autoimmune disorders. Hematological complications following this treatment are very common with the majority of patients experiencing at least one cytopenia after CAR-T cell injections. The management of these adverse events is not standardized and represents an area of active research and unmet clinical needs. This harmonization workshop, gathering a group of experts who analyzed this topic, has been conceived for the optimization of the management of patients presenting with post-CAR-T cell hematological toxicities. Based on the data present in the literature, these practical recommendations were made to harmonize the practices of Francophone centers involved in the management of these patients.

[Diet guidelines in adult and pediatric patient after allogeneic stem cell transplantation (SFGM-TC)]. / Consignes alimentaires pour les patients adultes et pédiatriques en sortie d'hospitalisation post-allogreffe de cellules souches hématopoïétiques (SFGM-TC).

The nutritional status after bone marrow transplant plays an important role in the outcome of patients. Post-allograft dietary instructions are therefore essential to ensure quality nutrition while minimizing the risk of infection. For patients, this is one of their main concerns on discharge from hospital. With the aim of harmonizing post-allograft dietary instructions, a multidisciplinary working group has been set up within a number of French centers performing hematopoietic stem cell allogenic transplantation. The dietary guidelines have been updated by this working group, through videoconference meetings, an online questionnaire, a review of the literature and deliberations at harmonization days. These instructions will be incorporated into the next update of the adult and pediatric post-transplant follow-up booklet.

[Haematopoietic stem cell donation from minor donor: Respecting laws, assessing fitness, delivering information and good care (SFGM-TC)]. / Don de cellules souches hématopoïétiques à partir d'un donneur mineur : cadre réglementaire, information, évaluation de l'aptitude au don et parcours (SFGM-TC).

Haematopoietic stem cell collection from paediatric donors is a common and life-saving practice, as evidenced by the fact that there is a growing annual number of cases of transplants from minor donors among SFGM-TC centers over the last decade. Still, medical use of human tissue from a healthy and underage donor requires proper regulations and medical management. The guidelines below aim at underlining the importance of pondering the legal, medical and ethical aspects of using stem cells from healthy paediatric donors and stress out the importance of obtaining informed consent at the time of assessing HLA compatibility. Combined medical and psychological assessments are required before the donation, as well as one month later and one year later to ensure of the child's physical and mental wellbeing. Bone marrow harvest under general anaesthetics remains the preferred method of collection for children. Peripheral blood stem cell collection should only be considered for children who will not require a central venous access for collection. We aim at offering guidelines centered on the healthy child donating stem cells and his/her wellbeing, and these should be regularly reviewed as medical practices evolve.

[Haemorrhagic cystitis following hematopoietic stem cell transplantation: Prophylaxis, diagnosis, and treatment. Guidelines from the SFGM-TC]. / La cystite hémorragique après allogreffe de cellules souches hématopoïétiques : prophylaxie, diagnostic, et traitement. Recommandations de la SFGM-TC.

Hemorrhagic cystitis (HC) is a common complication after allogeneic hematopoietic cell transplantation (allo-HCT). Its manifestations range from microscopic hematuria without urinary symptoms to extensive and prolonged macroscopic hemorrhage requiring invasive interventions that can often prolong the duration of hospitalization and result in significant morbidity. The early onset of HC is related to allo-HCT conditioning regimen, whereas the late onset form is secondary to viral infection, most commonly due to BK virus. In the framework of the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC) practice harmonization workshops held in Lille in September 2021, the prophylaxis, the diagnostic approach and the treatments of HC following allografting were reviewed after analysis of published studies.

Nilotinib efficacy and safety as salvage treatment following imatinib intolerance and/or inefficacy in steroid refractory chronic graft-versus-host-disease (SR-cGVHD): a prospective, multicenter, phase II study on behalf of the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC).

Imatinib is used for patients with SR-cGVHD. However, in 50% of cases imatinib is discontinued due to intolerance or inefficacy. In order to investigate nilotinib's role as salvage therapy in those patients, we conducted a prospective, multicenter, phase II study. (NCT02891395). Patients with SR-cGVHD were included to receive imatinib. Patients who stopped imatinib due to intolerance or inefficacy switched to Nilotinib. The primary endpoint was defined as the week-12 response rate to Nilotinib. The response was considered successful if superior to the 30% endpoint. Sixty-two patients started the IM-phase. Fourteen patients (22%) discontinued imatinib before week 12 due to: cGVHD progression (10%) or TKI-class-specific intolerance (12%). At week 12, we observed complete remission in 13 patients (21%) and partial response in 8 patients (13%). Twenty-nine patients switched to Nilotinib. Nilotinib response at week-12 was observed in 6 patients (21%) while 23 patients (79%) discontinued Nilotinib due to intolerance/cGVHD progression. The primary endpoint was not reached. This prospective study confirmed the efficacy of imatinib in patients with steroid refractory cGVHD. It failed to demonstrate the efficacy of nilotinib as a salvage therapy in patients who were intolerant/unresponsive to imatinib.

The promising efficacy of a risk-based letermovir use strategy in CMV-positive allogeneic hematopoietic cell recipients.

Letermovir is the first approved drug for cytomegalovirus (CMV) infection prophylaxis in adult patients who are CMV positive undergoing allogeneic hematopoietic cell transplantation (allo-HCT). Because CMV infection risk varies from patient to patient, we evaluated whether a risk-based strategy could be effective. In this single-center study, all consecutive adult patients who were CMV positive and underwent allo-HCT between 2015 and 2021 were included. During period 1 (2015-2017), letermovir was not used, whereas during period 2 (2018-2021), letermovir was used in patients at high risk but not in patients at low risk, except in those receiving corticosteroids. In patients at high risk, the incidence of clinically significant CMV infection (csCMVi) in period 2 was lower than that in period 1 (P < .001) by week 14 (10.5% vs 51.6%) and week 24 (16.9% vs 52.7%). In patients at low risk, although only 28.6% of patients received letermovir in period 2, csCMVi incidence was also significantly lower (P = .003) by week 14 (7.9% vs 29.0%) and week 24 (11.2% vs 33.3%). Among patients at low risk who did not receive letermovir (n = 45), 23 patients (51.1%) experienced transient positive CMV DNA without csCMVi, whereas 17 patients (37.8%) experienced negative results. In both risk groups, the 2 periods were comparable for CMV disease, overall survival, progression-free survival, relapse, and nonrelapse mortality. We concluded that a risk-based strategy for letermovir use is an effective strategy which maintains the high efficacy of letermovir in patients at high risk but allows some patients at low risk to not use letermovir.

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.

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.

Changes in bone mineral density after allogenic stem cell transplantation.

OBJECTIVE: Osteoporosis is a complication after allogenic stem cell transplantation (alloSCT). The purpose of this study was to assess changes in bone mineral density (BMD) 6 months and 3 years after alloSCT, as well as predictors of bone loss. METHODS: A longitudinal, prospective, single-center study was conducted at Lille University Hospital between 2005 and 2016. Clinical, biological, radiologic (thoracic and lumbar spine) and densitometric (DXA) assessments were carried out at baseline (pre-transplant), 6 months and 3 years. Patients with myeloma were not included. RESULTS: Two hundred and fifty-eight patients were included (144 men). Among them, 60.1% had leukemia and 65.8% of them, acute myeloid leukemia. At baseline, 6 months and 3 years, DXA-confirmed that osteoporosis was observed in 17%, 22.8% and 17.5% of the patients, respectively, mainly at the femoral neck. At baseline, 6 months and 3 years, 9 (8.5%), 53 (21.5%) and 38 (16.7%) patients, respectively, were receiving anti-osteoporotic treatment. From baseline to 6-month follow-up, BMD decreased significantly (p<0.001) at the lumbar spine (-36 [95%CI; -51 to -20] mg/cm2 of hydroxyapatite), femoral neck (-43 [95%CI; -57 to -29] mg/cm2 of hydroxyapatite) and total hip (-53 [95%CI; -68 to -39] mg/cm2 of hydroxyapatite). From 6-month to 3-year follow-up, a significant increase in BMD was observed at the lumbar spine only (+31 [95%CI; 20 to 42] mg/cm2 of hydroxyapatite, p<0.001). At all 3 sites, changes in BMD did not differ between patients treated or untreated by anti-osteoporotic treatment from 6-month to 3 year follow-up. Incident fractures were found in 4.1% and 5.7% of the patients at 6 months and 3 years, respectively. Between baseline and 6 months, bone loss at all 3 sites was associated with corticosteroid intake. At the total hip, 23.3% of the decrease in BMD from baseline to 6 months was due to an active hematological disease (p<0.05), a bone marrow stem cells (p<0.01) and a corticosteroid intake (p<0.01). CONCLUSION: Our study found evidence of bone fragility in alloSCT patients. Low BMD persisted at the hip 3 years after transplantation due to slower improvement at this site.

A case of subacute bowel obstruction revealing slowly-evolutive gastro-intestinal mucormycosis following allogeneic hematopoietic cell transplantation.

Gastro-intestinal mucormycosis (GIMM) is a highly lethal invasive fungal disease partly because of a challenging diagnosis. An allogeneic hematopoietic cell transplant recipient experienced bowel obstruction caused by slowly-evolutive gastro-intestinal mucormycosis and was successfully treated with surgery and antifungal therapy. Pathological findings revealed a granuloma without angio-invasion, which is unusual in this fungal disease and has incomplete similarities with an immune reconstitution inflammatory syndrome. Mucorales-specific PCR in both serum and resected tissue was positive and helped assessing the diagnosis. GIMM should be considered in front of unexplained granulomatosis or bowel obstruction in immunocompromised patients.

Successful allogeneic hematopoietic stem cell transplantation in patients with VEXAS syndrome: a 2-center experience.

The recently described vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic (VEXAS) syndrome is caused by somatic mutations in UBA1. Patients with VEXAS syndrome display late-onset autoinflammatory symptoms, usually refractory to treatment, and hematologic abnormalities. The identification of an easily-accessible specific marker (UBA1 mutations) is of particular interest as it allows the convergence of various inflammatory and hematological symptoms in a unique clinico-biological entity and gives the opportunity to design specific treatment strategies. Here we retrospectively identified 6 patients with VEXAS syndrome who underwent allogeneic hematopoietic stem cell transplantation (ASCT). To date, no treatment guidelines have been validated. In 4 patients, ASCT was guided by life-threatening autoinflammatory symptoms that were refractory to multiple therapies. Three patients are in durable complete remission 32, 38, and 37 months after ASCT. Two others are in complete remission response after 3 and 5 months. One unfortunately died post-ASCT. This report suggests that ASCT could be a curative option in patients with VEXAS syndrome and severe manifestations. Considering the complications and side effects of the procedure as well as the existence of other potential treatment, clinical trials are needed to define the subgroup of patients who will benefit from this strategy and its place in the therapeutic arsenal against VEXAS syndrome.