Directionality of HLA-DP permissive mismatches improves risk prediction in HCT for acute leukemia and MDS.

ABSTRACT: HLA-DP permissive mismatches can be assigned a direction according to their immunopeptidome divergence across core and noncore subsets. Noncore permissive graft-versus-host mismatches show significantly reduced risks of relapse without increased nonrelapse mortality compared with allele-matched pairs.

Younger unrelated donors may be preferable over HLA match in the PTCy era: a study from the ALWP of the EBMT.

ABSTRACT: There is a paucity of information on how to select the most appropriate unrelated donor (UD) in hematopoietic stem cell transplantation (HSCT) using posttransplant cyclophosphamide (PTCy). We retrospectively analyzed the characteristics of 10/10 matched UDs (MUDs) and 9/10 mismatched UDs (MMUDs) that may affect transplant outcomes in patients with acute myeloid leukemia (AML) in first or second complete remission (CR1 or CR2). The primary end point was leukemia-free survival (LFS). Overall, 1011 patients were included with a median age of 54 years (range, 18-77). Donors had a median age of 29 years (range, 18-64); 304 (30%) were females, of which 150 (15% of the whole group) were donors to male recipients, and 621 (61%) were MUDs; 522 (52%) had negative cytomegalovirus (CMV-neg) serostatus, of which 189 (19%) were used for CMV-neg recipients. Donor age older than 30 years had a negative impact on relapse (hazard ratio [HR], 1.38; 95% confidence interval [CI], 1.06-1.8), LFS (HR, 1.4; 95% CI, 1.12-1.74), overall survival (HR 1.45; 95% CI, 1.14-1.85) and graft-versus-host disease (GVHD) free, relapse-free survival (HR, 1.29; 95% CI, 1.07-1.56). In addition, CMV-neg donors for CMV-neg recipients were associated with improved LFS (HR, 0.74; 95% CI, 0.55-0.99). The use of MMUD and female donors for male recipients did not significantly impact any transplant outcomes. For patients undergoing HSCT from a UD with PTCy for AML, donor age <30 years significantly improves survival. In this context, donor age might be prioritized over HLA match considerations. In addition, CMV-neg donors are preferable for CMV-neg recipients. However, further research is needed to validate and refine these recommendations.

Prognostic impact of number of induction courses to attain complete remission in patients with acute myeloid leukemia transplanted with either a matched sibling or human leucocyte antigen 10/10 or 9/10 unrelated donor: An Acute Leukemia Working Party European Society for Blood and Marrow Transplantation study.

INTRODUCTION: For the majority of patients with acute myeloid leukemia (AML) an allogeneic stem cell transplant (SCT) in first complete remission (CR) is preferred. However, whether the number of courses required to achieve CR has a prognostic impact is unclear. It is unknown which factors remain important in patients requiring more than one course of induction to attain remission. METHODS: This Acute Leukaemia Working Party study from the European Society for Blood and Marrow Transplantation identified adults who received an allograft in first CR from either a fully matched sibling or 10/10 or 9/10 human leucocyte antigen (HLA)-matched unrelated donor (HLA-A, HLA-B, HLA-C, HLA-DR, or HLA-DQ). Univariate and multivariate analyses were undertaken to identify the prognostic impact of one or two courses of induction to attain CR. RESULTS: A total of 4995 patients were included with 3839 (77%) patients attaining a CR following one course of induction chemotherapy (IND1), and 1116 patients requiring two courses (IND2) to attain CR. IND2 as compared to IND1 was a poor prognostic factor in a univariate analysis and remained so in a multivariate Cox model, resulting in an increased hazard ratio of relapse (1.38; 95% confidence interval [CI], 1.16-1.64; p = .0003) and of death (1.27; 95% CI, 1.09-1.47; p = .002). Adverse prognostic factors in a multivariate analysis of the outcomes of patients requiring IND2 included age, FLT3-ITD, adverse cytogenetics, and performance status. Pretransplant measurable residual disease retained a prognostic impact regardless of IND1 or IND2. CONCLUSION: Initial response to chemotherapy as determined by number of courses to attain CR, retained prognostic relevance even following SCT in CR.

Higher survival following transplantation with a mismatched unrelated donor with posttransplant cyclophosphamide-based graft-versus-host disease prophylaxis than with double unit umbilical cord blood in patients with acute myeloid leukemia in first complete remission: A study from the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation.

The best donor option for acute myeloid leukemia (AML) patients lacking an HLA-matched donor has remained intensively debated. We herein report the results of a large retrospective registry study comparing hematopoietic cell transplantation (HCT) outcomes between double-unit umbilical cord blood transplantation (dCBT, n = 209) versus 9/10 HLA-matched unrelated donor (UD) with posttransplant cyclophosphamide (PTCy)-based graft-versus-host disease (GVHD) prophylaxis (UD 9/10, n = 270) in patients with AML in first complete remission (CR1). Inclusion criteria consisted of adult patient, AML in CR1 at transplantation, either peripheral blood stem cells (PBSC) from UD 9/10 with PTCy as GVHD prophylaxis or dCBT without PTCy, transplantation between 2013 and 2021, and no in vivo T-cell depletion. The 180-day cumulative incidence of grade II-IV acute GVHD was 29% in UD 9/10 versus 44% in dCBT recipients (p = .001). After adjustment for covariates, dCBT recipients had a higher non-relapse mortality (HR = 2.35, 95% CI: 1.23-4.48; p = .01), comparable relapse incidence (HR = 1.12, 95% CI: 0.67-1.86; p = .66), lower leukemia-free survival (HR = 1.5, 95% CI: 1.01-2.23; p = .047), and lower overall survival (HR = 1.66, 95% CI: 1.08-2.55; p = .02) compared with patients receiving UD 9/10 HCT. In summary, our results suggest that transplantation outcomes are better with UD 9/10 with PTCy-based GVHD prophylaxis than with dCBT for AML patients in CR1. These data might support the use of UD 9/10 with PTCy-based GVHD prophylaxis over dCBT in AML patients lacking an HLA-matched donor.

Impact of measurable residual disease on outcomes of unrelated donor haematopoietic cell transplantation with post-transplant cyclophosphamide in AML in first complete remission.

Pre-transplant measurable residual disease (MRD) predicts relapse and outcome of allogeneic haematopoietic cell transplantation (allo-HCT). The impact of MRD on the outcomes of post-transplant cyclophosphamide (PTCy)-based allo-HCT from a matched unrelated donor (UD) is unknown. This study assessed the impact of MRD in acute myeloid leukaemia (AML) in the first complete remission (CR1). A total of 272 patients (MRD negative [MRD-], n = 165; MRD positive [MRD+], n = 107) with a median follow-up of 19 (range: 16-24) months were studied. The incidence of grades II-IV and grades III-IV acute GVHD at day 180 was 25.2% and 25% (p = 0.99), and 10.6% and 6.8% (p = 0.29), respectively, and 2-year chronic GVHD was 35% and 30.4% (p = 0.96) in MRD+ and MRD- cohorts, respectively. In multivariate analysis, MRD+ status was associated with a higher incidence of relapse (RI) (hazard ratio [HR] = 2.56, 95% CI: 1.39-4.72), lower leukaemia-free survival (LFS) (HR = 2.04, 95% CI: 1.23-3.39), overall survival (OS) (HR = 1.83, 95% CI: 1.04-3.25) and GVHD-free, relapse-free survival (GRFS) (HR = 1.69, 95% CI: 1.10-2.58). MRD status did not have a significant impact on non-relapse mortality (NRM), or acute or chronic GVHD risk. Among patients with AML undergoing UD allo-HCT with PTCy, pre-transplant MRD+ status predicted a higher relapse rate, lower LFS, OS and GRFS.

Salvage haploidentical or cord-blood allogeneic stem cell transplantation after a prior alternative allograft in hematologic malignancies: A retrospective study from the SFGM-TC.

BACKGROUND: Haploidentical (haplo-) donors and cord-blood (CB) stem cells provide alternative transplant options in patients lacking an HLA-matched donor. In case of relapse or graft failure after a first alternative allogeneic hematopoietic stem cell transplant (HSCT), a second alternative HSCT (HSCT2) is rarely considered due to a high risk of toxicity. METHODS: A retrospective French multicentre study was performed, including patients with hematologic malignancies who underwent two consecutive HSCT from alternative donors. All data were exported from the national ProMISE database between 2000 and 2016. RESULTS: Forty-three patients (61.4%) received a CB-HSCT2 and 27 (38.6%) a haplo-HSCT2. Indications for HSCT were graft failure (51.4%) or disease progression (48.6%). Two-years probabilities of overall survival, progression-free survival and toxicity-related mortality were 18.5%, 17.8% and 55.8%, respectively. In multivariate analysis, complete remission status at HSCT2 and year of HSCT2 ≥ 2012 were significantly associated with a better outcome (with respectively hazard ratio [HR] = 0.42, p = .002 and HR = 0.5, p = .051). CONCLUSIONS: Neither the indication of HSCT2 nor the source of stem cell was more advantageous towards overall patient survival. A salvage haploidentical or cord-blood stem cell transplantation is a high-risk procedure, that may be considered for patients achieving a complete remission before receiving the second HSCT.

Impact of newly diagnosed extramedullary myeloma on outcome after first autograft followed by maintenance: A CMWP-EBMT study.

BACKGROUND: No adequate data exist on the impact of multiple myeloma (MM) with extramedullary disease (EMD) after autograft and maintenance therapy. METHODS: We identified 808 patients with newly diagnosed MM who received first autograft, of whom 107 had EMD (83 paraskeletal and 24 organ involvement), and who had been reported to the EBMT registry December 2018. Distribution according to type of involvement was similar between the treatment groups (p = .69). For EMD, 46 (40%) received thalidomide, 59 (51%) lenalidomide, and 11 (10%) bortezomib. RESULTS: The median follow-up from maintenance start was 44 months. Three-year progression-free survival (PFS) was 52% (48%-57%) for no EMD, 56% (44%-69%) for paraskeletal involvement, and 45% (22%-68%) for organ involvement (p = .146). Early PFS (within first year) appeared to be significantly worse for organ involvement (hazard ratio, 3.40), while no significant influence was found after first year from maintenance start. Three-year overall survival (OS) was 81% (77%-84%), 88% (80%-96%), and 68% (47%-89%; p = .064), respectively. With thalidomide as reference, lenalidomide was significantly associated with better PFS and OS, whereas bortezomib appeared to improve outcome specifically in EMD. CONCLUSION: Lenalidomide maintenance is standard of care for MM without EMD, whereas extramedullary organ involvement remains a significant risk factor for worse outcome, especially for early events after maintenance start.

On Behalf of the SFGM-TC: Prophylactic Donor Lymphocyte Infusion in Patients Treated with Allogeneic Stem-Cell Transplantation for High-Risk Myelodysplastic Syndrome and Acute Myeloid Leukemia.

INTRODUCTION: Allogeneic hematopoietic stem-cell transplantation (allo-HSCT) remains the best curative option for high-risk myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). Unfortunately, it is still associated with a significant risk of relapse due to mechanisms of escape from the control of alloreactive T cells. Repetitive adjuvant donor lymphocyte infusion (DLI), termed prophylactic DLI (proDLI), as an effective strategy in preventing relapse is still debated. METHODS: We performed a retrospective multicenter study to evaluate the efficacy of proDLI in allografted AML and MDS. We identified 56 patients treated with proDLI (DLI planned in full chimeras without any sign of disease relapse) and matched them to 167 patients in control group, (DLI performed for mixed chimerism or positive minimal residual disease) based on similar age, initial disease, cytogenetic prognosis, and conditioning intensity. RESULTS: In univariate analysis, the incidence of severe aGVHD at 100 days and incidence of all grades of chronic GVHD 1 year after allo-HSCT were similar in the two groups. We also observed a trend of higher 3-year RI (52.61% [95% confidence interval 25.99-79.23]) in the proDLI group versus the control group (29.31% [20.28-38.34], p = 0.067). However, 3-year overall survival (p = 0.892), progression-free survival (p = 0.239), and nonrelapse mortality (p = 0.343) were similar between the two groups. In multivariate analysis, the only factor influencing overall and progression-free survival was anti-thymocyte globulin administration during the conditioning regimen. CONCLUSION: The proDLI strategy had an acceptable toxicity profile but did not improve patient outcomes compared to the pre-emptive strategy.

Flow cytometric analysis of peripheral blood neutrophil myeloperoxidase expression for ruling out myelodysplastic syndromes: a prospective validation study.

Suspicion of myelodysplastic syndromes (MDS) is the most common reason for bone marrow aspirate in elderly patients. This study aimed to prospectively validate the accuracy for flow cytometric analysis of peripheral blood neutrophil myeloperoxidase expression in ruling out MDS. We enrolled 62 consecutive patients who were referred for suspected MDS, based on medical history and peripheral blood cytopenia. The accuracy of intra-individual robust coefficient of variation (RCV) for peripheral blood neutrophil myeloperoxidase expression was assessed with a prespecified 30% threshold. Cytomorphological evaluation of bone marrow aspirate performed by experienced hematopathologists confirmed MDS in 23 patients (prevalence, 37%), unconfirmed MDS in 32 patients (52%, including 3 patients with idiopathic cytopenia of undetermined significance (ICUS)), and was uninterpretable in 7 patients (11%). The median intra-individual RCV values for neutrophil myeloperoxidase expression in peripheral blood were 37.4% (range, 30.7-54.1), 29.2% (range, 28.1-32.1), and 29.1% (range, 24.7-37.8) for patients with confirmed suspicion of MDS, ICUS, and unconfirmed suspicion of MDS, respectively (P<0.001). The area under the ROC curve was 0.92 (95% confidence interval, 0.86-0.99). An intra-individual RCV value lower than 30% ruled out MDS for 35% (i.e., 19/55) patients referred for suspected disease, with 100% sensitivity (95% CI, 85-100%) and 100% negative predictive value (95% CI, 82-100%) estimates. This study shows that flow cytometric analysis of peripheral blood neutrophil myeloperoxidase expression might obviate the need for bone marrow aspirate for 35% of patients with suspected MDS. Trial registration: ClinicalTrials.gov identifier: NCT03363399 (first posted on December 6, 2017).

Molecular classification and prognosis in younger adults with acute myeloid leukemia and intermediate-risk cytogenetics treated or not by gemtuzumab ozogamycin: Final results of the GOELAMS/FILO acute myeloid leukemia 2006-intermediate-risk trial.

In this randomized phase 3 study, the FILO group tested whether the addition of 6 mg/m2 of gemtuzumab ozogamycin (GO) to standard chemotherapy could improve outcome of younger patients with de novo acute myeloid leukemia (AML) and intermediate-risk cytogenetics. GO arm was prematurely closed after 254 inclusions because of toxicity. A similar complete remission rate was observed in both arms. Neither event-free survival nor overall survival were improved by GO in younger AML patients (<60 years) ineligible for allogeneic stem-cell transplantation. (P = .086; P = .149, respectively). Using unsupervised hierarchical clustering based on mutational analysis of seven genes (NPM1, FLT3-ITD, CEBPA, DNMT3A, IDH1, IDH2, and ASXL1), six clusters of patients with significant different outcome were identified. Five clusters were based on FLT3-ITD, NPM1, and CEBPA mutations as well as epigenetic modifiers (DNMT3A, IDH1/2, ASXL1), whereas the last cluster, representing 25% of patients, had no mutation and intermediate risk. One cluster isolated FLT3-ITD mutations with higher allelic ratio and a very poor outcome. The addition of GO had no impact in these molecular clusters. Although not conclusive for GO impact in AML patients <60 years, this study provides a molecular classification that distinguishes six AML clusters influencing prognosis in younger AML patients with intermediate-risk cytogenetic.

Risk factors of BK viral hemorrhagic cystitis in allogenic hematopoietic stem cell transplantation.

Reactivation of BK virus (BKV) can occur during intensive immunosuppression such as in allogenic hematopoietic stem cell transplant (AHSCT) recipients for whom a systematic PCR urine test for BKV will be positive in 50% to 100% of patients. Only 5% to 40% will develop BKV hemorrhagic cystitis (HC). Thus, BKV PCR testing is useful to confirm a diagnosis of BKV-HC but not to predict its occurrence. The aim of this retrospective study was to ascertain the risk factors of developing BKV HC, mostly in patients receiving posttransplant cyclophosphamide. The study looked at data from Grenoble Alpes University Hospital included in the national retrospective register ProMISe, administered by the "Société Francophone de Greffe de Moelle et de Thérapie Cellulaire". Urine BKV PCR was performed when patients presented grade ≥ 2 hematuria with clinical symptoms of cystitis. BKV-HC was defined as an association of clinical symptoms of cystitis, grade ≥ 2 hematuria and BKV viruria > 7 log10 copies/ml. From January 2014 to January 2018, 168 AHSCTs were considered for analysis, of which 43 (25.6%) developed BKV-HC and 44.9% of the subgroup that received posttransplant cyclophosphamide. After logistic regression, the risk factors associated with BKV-HC were reduced to posttransplantation exposure to cyclophosphamide (OR 4.25, [1.66; 10.87], P = .02), age < 40 y (OR 3.85 [1.51; 9.80], P = .005) and corticosteroid therapy (OR 3.86, [1.59; 9.36], P = .003). Exposure to cyclophosphamide, younger age (<40) and corticosteroid therapy are potential risk factors for BKV-HC.

Outcomes of Salvage Haploidentical Transplant with Post-Transplant Cyclophosphamide for Rescuing Graft Failure Patients: a Report on Behalf of the Francophone Society of Bone Marrow Transplantation and Cellular Therapy.

Prognosis of patients with graft failure is dismal, and retransplantation is the sole option for long-term survival. To address the interest of haploidentical transplantation as a salvage option in this context, we analyzed data from 24 patients with graft failure or loss retransplanted with a haploidentical donor who received post-transplant cyclophosphamide (PTCy) as graft-versus-host disease prophylaxis (GVHD). Fludarabine-based reduced-intensity conditioning was used in 23 patients and the Baltimore regimen in 14 patients. The median delay between previous and salvage transplantation for graft failure was 63 days (range, 39 to 98). In addition to PTCy, all patients received cyclosporine, and 22 patients also received mycophenolate mofetil for GVHD prophylaxis. With a median follow-up of 353 days (range, 16 to 2010), 1-year overall survival (OS) was 56% (95% confidence interval, 38% to 81%). Transplant complications accounted for 80% of deaths. The cumulative incidence of neutrophil engraftment at day +30 was 79%. Cumulative incidence of grades II to IV acute GVHD at day 100 was 14%, and 1-year cumulative incidence of chronic GVHD was 31%. One-year cumulative incidence of relapse was 13%. Stem cell source did not impact on engraftment, GVHD, relapse, or OS. Salvage haploidentical transplant with PTCy for rescuing graft failure patients leads to an acceptable 1-year OS and might be a valid option in this poor situation.

HLA-DRB3/4/5 mismatches are associated with increased risk of acute GVHD in 10/10 matched unrelated donor hematopoietic cell transplantation.

Matching for HLA-A, -B, -C, and -DRB1 loci (8/8 match) is currently the gold standard for unrelated donor hematopoietic cell transplantation (HCT). In Europe, patients are also matched at the HLA-DQB1 loci (10/10 match). However, there is increasing evidence that matching at HLA-DRB3/4/5 loci may help to lower transplant-related morbidity and mortality. We therefore investigated the impact of HLA-DRB3/4/5 mismatches on outcomes in 1975 patients who received a first 10/10 matched unrelated donor (MUD) HCT in France from 2000 to 2012 for a hematological malignancy. High-resolution typing was performed at HLA-A, -B, -C, -DRB1, -DQB1, -DPB1, and -DRB3/4/5 loci for all donor/recipient pairs. Compared with DRB3/4/5-matched pairs, patients who received a MUD HCT from a DRB3/4/5 mismatched donor had a significantly increased risk of grade II-IV acute graft-versus-host disease (aGVHD) (Adjusted Hazard Ratio (HR) 1.43 (1.07 to 1.90)) associated with lower graft-versus-host disease-free and relapse-free survival (GRFS) (Adjusted HR 1.20 (1.02 to 1.42)). Conversely, we observed no differences in terms of chronic GVHD, nonrelapse mortality, relapse and overall survival. However, we believe that patients stand to benefit from DRB3/4/5 loci being considered for unrelated donor selection to improve GRFS and then quality of life after unrelated HCT.

Dynamics of Epstein-Barr viral load after hematopoietic stem cell transplantation and effect of preemptive rituximab therapy.

BACKGROUND: Epstein-Barr virus (EBV) displays oncogenic properties, particularly in the immunocompromised host. Notably, hematopoietic stem cell transplantation (HSCT) recipients with a detectable blood EBV viral load (BEBVL) are considered at higher risk of post-transplant lymphoproliferative diseases (PTLD). Therefore, BEBVL is monitored after HSCT, and preemptive rituximab may be used in patients with high values. However, little is known about post-HSCT BEBVL dynamics, and the threshold that should lead to anti-CD20 therapy is poorly defined. METHODS: We retrospectively analyzed the post-HSCT BEBVL of 332 adult HSCT recipients in our center from 2005 to 2013, including the effect of rituximab. RESULTS: Detection of BEBVL >100, 1000, 5000, 10 000, and 50 000 copies/mL occurred in, respectively, 77.7%, 69.6%, 37.0%, 27.1%, and 7.5% of the patients after a respective median time of 9, 14, 15, 16, and 14 weeks. No BEBVL threshold was associated with an overall survival difference. Seventy-eight patients received rituximab, with a BEBVL decrease in most. Among patients with detectable BEBVL, long-term survival did not differ in rituximab treated and non-treated, except for patients with BEBVL ≥50 000. Only one case of PTLD was observed. CONCLUSIONS: BEBVL is frequently detectable after HSCT, but suggests no strong association with survival. Preemptive rituximab therapy threshold remains to be defined.

Hematopoietic Stem Cell Transplantation in Multiple Myeloma: A Retrospective Study of the Société Française de Greffe de Moelle et de Thérapie Cellulaire (SFGM-TC).

Because the indication of allograft (allogeneic stem cell transplantation [alloSCT]) for multiple myeloma (MM) has widened in recent years, thanks to the development of reduced-intensity conditionings (RIC), it is still unclear if myeloablative conditioning (MAC) remains appropriate. This study compares retrospectively outcomes of patients undergoing either RIC or MAC regimens for MM. Based on the SFGM-TC registry, we included 446 MM patients receiving alloSCT between 1999 and 2009 for whom a minimal data set was available. Median follow-up for the entire cohort was 33.6 months (range, 0 to 164.5). RIC and MAC populations were different regarding age (53.5 versus 47.1 years, respectively), number of prior autologous (auto)SCTs (93.2% versus 79.6% had at least 2 autoSCTs), and stem cell source (90.2% versus 61.2% received peripheral blood). For RIC and MAC populations the nonrelapse mortality at 2 years was 24.6% and 22.4%, respectively, progression-free survival 35.5% and 51.1%, and overall survival 59.5% and 66.7% (not significant). These outcomes were not affected by conditioning intensity either on univariate or multivariate analysis. Despite some limitations in the study design, these results indicate that MAC should remain a valuable option in alloSCT for MM, especially for young and less-treated patient with no comorbidity. The constant progress in induction treatments of MM and supportive care after alloSCT could improve these results in the near future.

Decreased nonrelapse mortality after unrelated cord blood transplantation for acute myeloid leukemia using reduced-intensity conditioning: a prospective phase II multicenter trial.

A prospective phase II multicenter trial was performed with the aim to obtain less than 25% nonrelapse mortality (NRM) after unrelated cord blood transplantation (UCBT) for adults with acute myeloid leukemia (AML) using a reduced-intensity conditioning regimen (RIC) consisting of total body irradiation (2 Gy), cyclophosphamide (50 mg/kg), and fludarabine (200 mg/m(2)). From 2007 to 2009, 79 UCBT recipients were enrolled. Patients who underwent transplantation in first complete remission (CR1) (n = 48) had a higher frequency of unfavorable cytogenetics and secondary AML and required more induction courses of chemotherapy to achieve CR1 compared with the others. The median infused total nucleated cells (TNC) was 3.4 × 10(7)/kg, 60% received double UCBT, 77% were HLA mismatched (4/6), and 40% had major ABO incompatibility. Cumulative incidence of neutrophil recovery at day 60 was 87% and the cumulative incidence of 100-day acute graft-versus-host disease (II to IV) was 50%. At 2 years, the cumulative incidence of NRM and relapse was 20% and 46%, respectively. In multivariate analysis, major ABO incompatibility (P = .001) and TNC (<3.4 × 10(7)/kg; P = .001) were associated with increased NRM, and use of 2 or more induction courses to obtain CR1 was associated with increased relapse incidence (P = .04). Leukemia-free survival (LFS) at 2 years was 35%, and the only factor associated with decreased LFS was secondary AML (P = .04). In conclusion, despite the decreased NRM observed, other RIC regimens with higher myelosuppression should be evaluated to decrease relapse in high-risk AML. (EUDRACT 2006-005901-67).

Variability of voriconazole plasma concentrations after allogeneic hematopoietic stem cell transplantation: impact of cytochrome p450 polymorphisms and comedications on initial and subsequent trough levels.

Voriconazole (VRC) plasma trough concentrations (Cmin) are highly variable, and this could affect treatment efficacy and safety in patients undergoing allogeneic hematopoietic stem cell transplantation (AHSCT). We aimed to describe the intra- and interindividual variation of VRC Cmin throughout the course of VRC therapy and to identify the determinants of this variation. Clinical data, medications, and VRC Cmin (n = 308) of 33 AHSCT patients were retrospectively collected. Cytochrome P450 (CYP450) genotypes of CYP2C19, CYP3A4, and CYP3A5 patients were retrospectively determined before allografting, and a combined genetic score was calculated for each patient. The higher the genetic score, the faster the metabolism of the patient. The VRC Cmin inter- and intraindividual coefficients of variation were 84% and 68%, respectively. The VRC dose (D) was correlated to VRC Cmin (r = 0.412, P < 0.0001) only for oral administration. The administration route and the genetic score significantly affected the initial VRC Cmin. Considering oral therapy, patients with a genetic score of <2 had higher initial VRC Cmin/D than patients with a genetic score of >2 (P = 0.009). Subsequent VRC Cmin remained influenced by the genetic score (P = 0.004) but were also affected by pump proton inhibitor comedication (P < 0.0001). The high variability of VRC Cmin in AHSCT patients is partially explained by the route of administration, treatment with pump proton inhibitors, and the combined genetic score. This study suggests the interest in combined genetic score determination to individualize a priori the VRC dose and underlines the need for longitudinal therapeutic drug monitoring to adapt subsequent doses to maintain the VRC Cmin within the therapeutic range.

Prospective evaluation of gene mutations and minimal residual disease in patients with core binding factor acute myeloid leukemia.

Not all patients with core binding factor acute myeloid leukemia (CBF-AML) display a good outcome. Modern risk factors include KIT and/or FLT3 gene mutations and minimal residual disease (MRD) levels, but their respective values have never been prospectively assessed. A total of 198 CBF-AML patients were randomized between a reinforced and a standard induction course, followed by 3 high-dose cytarabine consolidation courses. MRD levels were monitored prospectively. Gene mutations were screened at diagnosis. Despite a more rapid MRD decrease after reinforced induction, induction arm did not influence relapse-free survival (RFS) (64% in both arms; P = .91). Higher WBC, KIT, and/or FLT3-ITD/TKD gene mutations, and a less than 3-log MRD reduction after first consolidation, were associated with a higher specific hazard of relapse, but MRD remained the sole prognostic factor in multivariate analysis. At 36 months, cumulative incidence of relapse and RFS were 22% vs 54% (P < .001) and 73% vs 44% (P < .001) in patients who achieved 3-log MRD reduction vs the others. These results suggest that MRD, rather than gene mutations, should be used for future treatment stratifications in CBF-AML patients. This trial was registered at EudraCT as #2006-005163-26 and at www.clinicaltrials.gov as #NCT 00428558.