Post-transplant Maintenance Therapy Research Articles

Post-Transplant Maintenance Therapy in Acute Myeloid Leukemia

Post-Transplant Maintenance Therapy in Acute Myeloid Leukemia

Azacitidine and gemtuzumab ozogamicin as post-transplant maintenance therapy for high-risk hematologic malignancies.

Disease recurrence remains the principal cause of treatment failure after allogeneic hematopoietic stem cell transplantation. Post-transplant maintenance therapy with azacitidine (AZA) is promising to prevent relapse but the outcomes are unsatisfactory in patients at high risk of recurrence. Herein, we evaluated the outcome in patients who received AZA and gemtuzumab ozogamicin (GO), anti-CD33 antibody-calicheamicin conjugate, as post-transplant maintenance therapy. Twenty-eight patients with high-risk hematologic malignancies harboring CD33-positive leukemic blasts received the maintenance therapy. AZA (30 mg/m2) was administered for 7 days, followed by GO (3 mg/m2) on day 8. The maximum number of cycles was 4. At transplant, 21 patients (75.0%) had active disease. Their 2-year overall survival, disease-free survival, relapse, and non-relapse mortality rates were 53.6%, 39.3%, 50.0%, and 10.7%, respectively. Of these patients, those with minimal residual disease at the start of maintenance therapy (n = 9) had a higher recurrence rate (66.7% vs. 42.1% at 2 years, P = 0.069) and shorter disease-free survival (11.1% vs. 52.6% at 2 years, P = 0.003). Post-transplant maintenance therapy with AZA and GO was generally tolerable but more than half of the patients eventually relapsed. Further improvements are needed to prevent relapse after transplantation in patients with high-risk hematologic malignancies.

Role of B Cells beyond Antibodies in HBV-Induced Oncogenesis: Fulminant Cancer in Common Variable Immunodeficiency-Clinical and Immunotransplant Implications with a Review of the Literature.

Although lymphoma is the most frequent malignancy in common variable immunodeficiency (CVID), solid tumors, especially affected by oncogenic viruses, are not considered. Furthermore, in vitro genetic studies and cell cultures are not adequate for immune system and HBV interaction. We adopted a previously introduced clinical model of host-virus interaction (i.e., infectious process in immunodeficiency) for analysis of B cells and the specific IgG role (an observational study of a CVID patient who received intravenous immunoglobulin (IVIG). Suddenly, the patient deteriorated and a positive results of for HBs and HBV-DNA (369 × 106 copies) were detected. Despite lamivudine therapy and IVIG escalation (from 0.3 to 0.4 g/kg), CT showed an 11 cm intrahepatic tumor (hepatocellular carcinoma). Anti-HBs were positive in time-lapse analysis (range 111-220 IU/mL). Replacement therapy intensification was complicated by an immune complex disease with renal failure. Fulminant HCC in CVID and the development of a tumor as the first sign is of interest. Unfortunately, treatment with hepatitis B immune globulins (HBIG) plays a major role in posttransplant maintenance therapy. Anti-HB substitution has not been proven to be effective, oncoprotective, nor safe. Therefore, immunosuppression in HBV-infected recipients should be carefully minimized, and patient selection more precise with the exclusion of HBV-positive donors. Our clinical model showed an HCC pathway with important humoral host factors, contrary to epidemiological/cohort studies highlighting risk factors only (e.g., chronic hepatitis). The lack of cell cooperation as well as B cell deficiency observed in CVID play a crucial role in high HBV replication, especially in carcinogenesis.

Innovations in conditioning and post-transplant maintenance in AML: genomically informed revelations on the graft-versus-leukemia effect.

Acute Myeloid Leukemia (AML) is the prototype of cancer genomics as it was the first published cancer genome. Large-scale next generation/massively parallel sequencing efforts have identified recurrent alterations that inform prognosis and have guided the development of targeted therapies. Despite changes in the frontline and relapsed standard of care stemming from the success of small molecules targeting FLT3, IDH1/2, and apoptotic pathways, allogeneic stem cell transplantation (alloHSCT) and the resulting graft-versus-leukemia (GVL) effect remains the only curative path for most patients. Advances in conditioning regimens, graft-vs-host disease prophylaxis, anti-infective agents, and supportive care have made this modality feasible, reducing transplant related mortality even among patients with advanced age or medical comorbidities. As such, relapse has emerged now as the most common cause of transplant failure. Relapse may occur after alloHSCT because residual disease clones persist after transplant, and develop immune escape from GVL, or such clones may proliferate rapidly early after alloHSCT, and outpace donor immune reconstitution, leading to relapse before any GVL effect could set in. To address this issue, genomically informed therapies are increasingly being incorporated into pre-transplant conditioning, or as post-transplant maintenance or pre-emptive therapy in the setting of mixed/falling donor chimerism or persistent detectable measurable residual disease (MRD). There is an urgent need to better understand how these emerging therapies modulate the two sides of the GVHD vs. GVL coin: 1) how molecularly or immunologically targeted therapies affect engraftment, GVHD potential, and function of the donor graft and 2) how these therapies affect the immunogenicity and sensitivity of leukemic clones to the GVL effect. By maximizing the synergistic action of molecularly targeted agents, immunomodulating agents, conventional chemotherapy, and the GVL effect, there is hope for improving outcomes for patients with this often-devastating disease.

Symptom clusters and their impact on quality of life in multiple myeloma survivors: Secondary analysis of BMT CTN 0702 trial.

Autologous haematopoietic cell transplantation (autoHCT) and continuous post-transplant maintenance therapy are the standard of care in transplant-eligible multiple myeloma (MM) patients. We sought to describe symptom burden and identify symptom clusters occurring in MM patients after autoHCT using data from the BMT CTN 0702 randomized controlled trial comparing the outcomes of three treatment interventions after an autoHCT in 758 MM patients. We analysed individual transplant-related symptoms assessed via the FACT-BMT questionnaire at enrolment and annually for 4-year post-autoHCT. We also described the effect the individual symptoms and symptom clusters have on quality of life (QoL). We identified three stable symptom clusters: malaise symptom cluster (lack of energy, feeling ill, having pain, experiencing nausea, loss of appetite), physical symptom cluster (having skin problems, tremors, worsening eyesight, change in taste, shortness of breath, frequent colds) and emotional symptom cluster (feeling sad, being nervous, experiencing sleep problems). Malaise and emotional symptom clusters have a greater impact on QoL than the physical symptoms cluster. Identifying these symptoms warrant additional support in terms of psychosocial support, in addition to treatment of the physical symptoms themselves.

Ponatinib Improved the Prognosis of Philadelphia Chromosome-Positive Acute Lymphoblastic Leukemia: A Japanese Single-Center Cohort Study.

Introduction The overall survival (OS) of Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL) has improved with the combination of tyrosine kinase inhibitor (TKI) with intensive chemotherapy. In recent years, there has been increased interest in the possibility of long-term survival without allogeneic hematopoietic stem cell transplantation (HSCT) or maintenance therapy. The aim of this study was to determine the effectiveness of treatment and the resultant outcomes in Ph+ALL patients using real-world data. Methods We performed a single-center retrospective analysis utilizing Akita University Hospital data (Akita, Japan) from November 2000 to June 2023 to evaluatethe outcomes of TKI with intensive chemotherapy for Ph+ALL. Results Twenty-three patients with Ph+ALL were treated with intensive chemotherapy combined with TKI, including six imatinib, four dasatinib, and 13 ponatinib. The median patient age was 53 years (range; 28-67). Eighteen patients (78%) achieved complete molecular remission (CMR) within three months. HSCT was performed in 16 patients (70%), all of whom did not receive post-transplant TKI maintenance therapy. Six of the seven patients who did not undergo HSCT received maintenance therapy with ponatinib after intensive chemotherapy. The three-year OSwas 81%. Ponatinib treatment resulted in a much higher OS rate than imatinib/dasatinib (100% vs. 60%;P=0.011). CMR within three months was identified as a prognostic factor for molecular relapse-free survival (hazard ratio (HR)=0.22;P=0.027). CD20 positivity was identified as a risk factor for hematological relapse (HR=5.2, P=0.032). Conclusion Even in a single-center cohort study, ponatinib, as a combination TKI with intensive chemotherapy or maintenance therapy, may improve the prognosis of Ph+ALL. Patients with CMR within three months might not necessarily needto receive HSCT, but a subsequent treatment-free status could have been achieved only by HSCT. Furthermore, CD20 positivity may be a useful biomarker for future treatment decisions in patients with Ph+ALL.

Analysis of Post-Transplant Clinical Outcomes and Prognostic Factors in FLT3-ITD Mutated Acute Myeloid Leukemia Patients Under ELN 2022 Risk Stratification

Background In 2022 European LeukemiaNet (ELN) recommendations for diagnosis and management of acute myeloid leukemia (AML), one of the most important changes made to the genetic risk classification of AML is that the FLT3-ITD allelic ratio (AR) is no longer considered in the risk classification; consequently, AML with FLT3-ITD (without adverse-risk genetic lesions) are now categorized in the intermediate-risk group, irrespective of the allelic ratio or concurrent presence of NPM1 mutation. Aims To investigate the survival outcomes of FLT3-ITD mutated AML patients underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT), based on prognostic stratification defined by the 2017 and 2022 ELN guidelines, and to analyze the risk factors affecting transplant prognosis. Methods A total of 163 FLT3-ITD mutated AML patients underwent allo-HSCT were enrolled in this study. Bone marrow aspirates were obtained, cytogenetic and molecular characteristics were collected at the time of diagnosis. Genetic risk category was classified according to the 2017 and 2022 edition of the European LeukemiaNet (ELN) recommendations. HLA-haploidentical donor transplants were performed if no HLA matched sibling or unrelated donor was available. Patients received myeloablative conditioning with a modified Bu/Cy/Flu/Ara-c (busulfan/cyclophosphamide/fludarabine/cytarabine) or MCBC (melphalan/cladribine/busulfan/cyclophosphamide) preparative regimen. The therapeutic process and clinical outcomes were retrospectively analyzed. Results We assessed 163 adults with FLT3-mutated AML (median age 37 years) allografted between 2017 and 2022 in our clinical center. The median follow-up of alive patients was 24.9 months. The 2-year relapse-free survival (RFS) and overall survival (OS) were 67.2% and 71.9%, respectively. The 2-year incidences of relapse and non-relapse mortality were 27.9% and 12.5%, respectively. There was no significant difference in survival outcomes between the intermediate and high-risk groups after transplantation, both defined by the 2017 and 2022 ELN guidelines. High FLT3-ITD allelic ratio (≥0.5) at initial diagnosis was associated with elevated WBC counts ( P<0.001), but did not affect the response ratefollowing induction chemotherapy ( P=0.059) . Patients with high allelic ratio were more likely to benefit from maintenance therapy after transplantation ( P=0.048 for OS). In univariate analysis, presence of NPM1 mutation and the allelic ratio of FLT3-ITD did not affect any of the transplant outcomes. In multivariate analysis, MRD-negative at transplantation, occurrence of chronic GVHD and posttransplant maintenance therapy improved OS and RFS. Conclusion Allo-HSCT can overcome the poor prognosis in patients with FLT3-ITD mutated AML. Neither the presence of NPM1 mutation nor the FLT3-ITD allelic ratio affected survival. Prevention of disease relapse after transplantation remains a challenge. The main prognostic factors affecting transplant outcomes included pre-transplant MRD status and the application of maintenance therapy. Thus, introduction of FLT3 inhibitors as post-transplant maintenance therapy and the development of highly sensitive MRD assays will further reduce disease recurrence and improve survival.

Outcomes of Patients with Multiple Myeloma and 1q Gain/Amplification Receiving Autologous Hematopoietic Stem Cell Transplant: The MD Anderson Cancer Center Experience

Background: There is contradictory data regarding the prognostic impact of additional copy numbers of chromosome 1q (1q+) on the outcomes of newly diagnosed multiple myeloma (NDMM) patients, and there is scarce data in the context of autologous stem cell transplantation (autoSCT). In this report, we studied outcomes of NDMM patients with 1q+ who received induction with contemporary anti-myeloma agents, followed by autoSCT and post-transplant maintenance therapy. Methods: We conducted a retrospective single-center chart review analysis of adult NDMM patients with 1q21 gain or amplification (3 or ≥4 copies of 1q, respectively; 1q+) detected by fluorescence in situ hybridization (FISH) that received autoSCT between 2008-2018. Progression-free survival (PFS) and overall survival (OS) were the primary endpoints. Results: 213 NDMM patients with 1q+ were included in the analysis, with a median age of 62.5 years and 53% were male. Overall, 169 (79%) patients had 1q gain, while 44 (21%) patients had 1q amplification. The most commonly used induction and conditioning regimens were bortezomib, lenalidomide, and dexamethasone (VRD) (41%) and melphalan (77%), respectively (Table 1). At day 100 after autoSCT and at best post-transplant response, 78% and 87% of patients achieved ≥VGPR, 34% and 56% achieved CR, 38% and 50% achieved MRD negative ≥VGPR, respectively. The median PFS and OS for the entire cohort were 35.5 months and 81.4 months, respectively. 1q amplification was associated with inferior PFS compared to 1q gain (HR=2.03, 95% CI 1.36-3.03, p<0.001; Figure 1). On multivariable assessment (MVA) for PFS, MRD negative >VGPR before autoSCT and at day 100 post-transplant [(HR=0.56, 95% CI 0.36-0.86, p=0.009) and (HR=0.64, 95% CI 0.44-0.94, p=0.022), respectively] were associated with better PFS, whereas 1q amplification was associated with inferior PFS (HR=1.94, 95% CI 1.29-2.92, p=0.001). On MVA for OS, R-ISS stage III (HR=4.08, 95% CI 1.07-15.50, p=0.039) was associated with inferior OS, whereas achieving MRD negative >VGPR at best post-transplant response was associated with superior OS (HR=0.45, 95% CI 0.24-0.85, p=0.014). Notably, the percentage of cells with 1q+ was not associated with PFS nor with OS, both when evaluated as a continuous variable and when evaluated as a categorical variable using thresholds of either 30% or 50%. The presence of additional high-risk cytogenetic abnormalities did not adversely affect survival outcomes. Conclusions: Patients with NDMM and 1q+, especially 1q amplification, have poor survival outcomes, despite the use of contemporary induction regimens, upfront autoSCT and post-transplant maintenance. These patients may benefit from novel treatment modalities, such as CAR-T and bispecific antibodies, earlier in their disease course.

Real World Experience of FLT3-Inhibitor Post-Transplant Maintenance with Sorafenib Demonstrating Superior Overall- and Relapse Free Survival Following Allogeneic Hematopoietic Stem Cell Transplantation in FLT3-ITD Mutated Acute Myeloid Leukemia

Introduction Acute myeloid leukemia (AML) with FLT3-internal tandem duplication (ITD) is known to have a significantly high risk of relapse even with allogeneic stem cell transplantation (HCT), for which post-transplant maintenance therapy with FLT3 inhibitors (FLT3i) has been applied. Although there is a randomized trial comparing Sorafenib maintenance vs no treatment, real world experience is still limited. Despite the increased use of FTL3i maintenance in clinical practice, the optimal dose and duration of post-transplant Sorafenib maintenance remains uncertain. Accordingly, we performed a retrospective chart review to analyze the survival benefit with Sorafenib maintenance, dose tolerability and the impact of FLT3-ITD allele frequency (AF) at initial diagnosis of AML on treatment outcomes in the context of post-HCT Sorafenib maintenance. Patients and method We conducted a retrospective study including 69 patients who received an allogeneic HCT from 2019 to 2023 for AML with FLT3-ITD, of which 24 patients received Sorafenib as post-HCT maintenance therapy. Primary endpoint was relapse-free survival (RFS). The use of Sorafenib maintenance treatment was treated as a time-dependent covariate and Mantel-Byar test (MBT) was conducted to compare outcomes between Sorafenib maintenance group vs others, which will avoid immortal bias. FLT3-ITD allele frequency (AF) was assessed by molecular PCR test, and the cutoff was determined using a binary recursive partitioning method with AF of 54.6% as a cutoff. Results Out of 69 patients, 61 (88%) were in CR1 vs 8 (12%) in CR2 prior to HCT. Sorafenib was started in 24 patients (35%) at a median of 95 days post-HCT with a dose of 200mg every other day (n=2), 200mg once daily (n=17) or 200mg twice daily (n=5). The most common maintenance dose was 200mg once daily (n=9), followed by 200mg twice daily (n=6), 200mg every other day (n=5), and 400mg twice daily (n=1). The median Sorafenib maintenance duration was 15 months (1-53 months) at the last follow-up. There were no relapses in the patients who completed 2 years of Sorafenib maintenance. Sorafenib was discontinued in 6 patients, due to relapse (n=2), death of unrelated cause (n=1), GVHD (n=1), pneumonitis (n=1) and recurrent hypoglycemia (n=1). Adverse events requiring Sorafenib dose reduction included, GI intolerance (n=7), skin rash (n=7), thrombocytopenia (n=4), transaminitis (n=3), neuropathy (n=3), GVHD (n=2) and pneumonitis (n=2). The median follow-up duration for all the patients was 27 months (5-51) following HCT, or 13 months (1.3-48) following Sorafenib maintenance. Using Kaplan-Meier test, the 2-year RFS in patients on Sorafenib maintenance was 84.5% vs 40.5% for no Sorafenib (p=0.00049). The 2-year OS was 88.2% vs 53.9% (p=0.0043), respectively. The CIR was 9.8% vs 39.9% (p=0.00634), while the NRM was 5.6% vs 19.7% (p =0.122), respectively. In the MBT, Sorafenib maintenance was found to reduce the mortality risk by 62.5% (HR 0.375 (0.109-1.29], p=0.120) and reduced the relapse/mortality risk by 71.2% (HR 0.288 [0.084-0.984], p=0.047). With respect to FLT3-ITD AF, the group with higher AF showed extremely higher HR for RFS compared to those with lower FLT-ITD (HR 29.37 [3.007-286.8], p=0.0036). When evaluating RFS and OS with combined risk incorporating the use of Sorafenib and FLT3-ITD AF, we have 4 subgroups (figure 1). In patients with a lower AF, the RFS was 87.7% vs 56.8% in the Sorafenib (n=20), vs no Sorafenib group (n=31), respectively. In patients with a higher AF, the RFS was 66.7% vs 0.0% in the Sorafenib (n=3), vs no Sorafenib group (n=8; p=0.0009), respectively. In a multivariate analysis, we confirmed the 2-year RFS for patients who had a high FLT3-ITD and received Sorafenib maintenance was statistically significant when compared to no Sorafenib maintenance. Conclusion Sorafenib maintenance post-transplant in FLT3-ITD mutated AML patients significantly improves the OS and RFS. Sorafenib maintenance is tolerable with 200mg twice daily or lower in most patients. Reduced doses of Sorafenib improve tolerability, with no significant impact on increased risk of relapse. Higher AF group of FLT3-ITD at initial diagnosis defined by ≥54.6% using PCR, was associated with significantly increased risk of relapse even after HCT. Sorafenib maintenance seems to provide survival benefit in terms of RFS, particularly in the patients with higher AF FLT3-ITD.

Ex Vivo Drug Sensitivity Evaluation of a ZMYM2::FGFR1 Fusion-Positive 8p11 Myeloproliferative Syndrome (EMS) Leukemia

Introduction : Fibroblast growth factor receptors (FGFRs) are conserved single transmembrane receptor tyrosine kinases (RTKs) with an extracellular ligand-binding domain and a cytoplasmic tyrosine kinase domain. They play vital roles in cellular proliferation, survival, development, fetal organogenesis, metabolism, and tissue repair. 8p11 myeloproliferative syndrome (EMS) is a hematologic malignancy caused by a translocation of the fibroblast growth factor receptor 1 (FGFR1) gene on chromosome 8p11-12. The most common fusion partner of FGFR1 is the zinc-finger domain ZNF198 (also known as ZMYM2) on chromosome 13q12. Pemigatinib is approved for FGFR fusion positive myeloid/lymphoid neoplasms (MLNs), and other FGFR inhibitors are being tested in clinical trials. However, EMS patients still face a poor prognosis and drug resistance, necessitating further research to overcome these challenges. This study evaluated ex vivo drug screening assay data generated from ZMYM2::FGFR1 positive primary leukemia samples throughout the course of an EMS patient's clinical response and validated these findings on a ZMYM2::FGFR1 positive cell line. Methods : Ex vivo and drug screening experiments were performed on freshly isolated primary patient samples and a ZMYM2::FGFR1-expressing cell line. The fusion was confirmed using FISH, and additional clinical specimens were collected with informed patient consent. Ex vivo drug sensitivity assays were conducted on patient mononuclear cells isolated from blood and bone marrow. IL-3 dependent BaF3 cells were infected with retrovirus containing a ZMYM2::FGFR1-V5 construct. ZMYM2::FGFR1 transformed BaF3 cells were evaluated with single agent and drug combination panels. Sanger sequencing of the FGFR portion of the fusion was performed on patient samples to confirm the breakpoint and identify potential mutations affecting sensitivity to Ponatinib throughout the course of treatment. Results : Sample were obtained with informed consent from a 36-year-old man diagnosed with 8p11 myeloproliferative syndrome and a ZMYM2::FGFR1 fusion along with a RUNX1 R201Q mutation. Ex vivo drug screens performed on isolated mononuclear cells demonstrated sensitivity to Ponatinib and Pemigatinib. He underwent treatment with HyperCVAD plus Ponatinib and subsequently HyperCVAD with Ponatinib and Velcade (Bortezomib) to CR1, FISH for FGFR1 rearrangement was undetected. He was scheduled to proceed with hematopoietic stem cell transplant (HSCT), however his pre-transplant bone marrow biopsy showed return of his FGFR1 translocation by FISH. Ex vivo drug screening assays confirmed resistance to Ponatinib, but continued sensitivity to Pemigatinib. He was transitioned to treatment with single agent Pemigatinib and was able to re-clear his FGFR1 fusion by FISH, and has since undergone hematopoietic stem cell transplantation. He remains in remission on post-transplant Pemigatinib maintenance therapy. Sanger sequencing performed at the time of progression on Ponatinib identified a nucleotide alteration resulting in an amino acid substitution (FGFR1 F686L; ZMYM2::FGFR1 F1171L) within the kinase domain that could contribute to decreased Ponatinib sensitivity. Bortezomib and Axitinib exhibited high efficacy on the patient's sample. Ex vivo drug assays performed on ZMYM2::FGFR1 transformed BaF3 cells confirmed the efficacy of Pemigatinib and Ponatinib. Other FGFR inhibitors, including Olverematinib, AZD4547, Axitinib, Cediranib, Dovitinib, and Lenvatinib, also demonstrated exquisite sensitivity. Despite extensive screening, no other single agents or drug combinations exhibited increased effectiveness in the ZMYM2::FGFR1 transformed BaF3 cells except for Trametinib, a MEK inhibitor, and the combination of Belvarafenib (RAF inhibitor) and Gilteritinib (FLT3 inhibitor). Conclusions : Ex vivo drug sensitivity assays demonstrated the highly selective efficacy of FGFR inhibitors in ZMYM2::FGFR1 fusion-positive leukemia cells and a fusion-expressing BaF3 cell line. Mutations in the FGFR1 kinase domain (ZMYM2::FGFR1 F1171L) could contribute to Ponatinib insensitivity. These ex vivo drug screening results provide further support for ongoing clinical trials which are investigating the use of single agent Pemigatinib and other FGFR1 inhibitors for the treatment of patients with FGFR1-fusion positive leukemias.

Post-Hoc Analysis of Measurable Residual Disease from BMT-CTN 1506/Morpho: FLT3-ITD Variant Allele Frequency and Survival Are Highly Correlated

Background: BMT CTN 1506/MORPHO was a randomized study of the FLT3 inhibitor gilteritinib versus placebo as post-transplant (HCT) maintenance therapy for patients (pts) with FLT3-ITD acute myeloid leukemia (AML). Patients with FLT3-ITD AML in first remission underwent HCT and then were randomized, in double-blind fashion, to either gilteritinib or placebo for 24 months. The primary endpoint was relapse-free survival (RFS), and a pre-specified secondary endpoint was the effect of measurable residual disease (MRD) on survival as detected by a highly sensitive assay for FLT3-ITD mutations. In the primary analysis, while RFS was higher for pts randomized to gilteritinib, the difference did not reach the pre-determined threshold for significance (HR: 0.679; 95% CI: 0.459, 1.005; 2-sided p-value: 0.0518). However, in the secondary analysis, the 50.6% of pts who had MRD detectable pre- or post-HCT had significantly higher RFS with gilteritinib (HR of relapse or death=0.515, 95% CI: 0.316, 0.838, p = 0.0065). In this post-hoc analysis, we examined 1) the impact on RFS of different levels of FLT3-ITD variant allele frequency (VAF) pre-randomization (immediately before or after HCT but prior to randomization to gilteritinib or placebo); 2) the impact of the presence of multiple mutations detected as MRD pre-HCT; and 3) the eradication of FLT3-ITD clones detected post-HCT during follow up on gilteritinib or placebo. Methods: First-pull marrow aspirates were collected from pts at two time points pre-randomization (pre-HCT and between 30-90 days post-HCT), as well as at 3, 6, 12, 18, and 24 months post-randomization. For MRD detection (performed at Invivoscribe; San Diego, CA), 700 ng input DNA was amplified by polymerase chain-reaction (PCR) using 25 cycles and primers flanking exons 14 and 15 of FLT3, followed by next-generation sequencing (NGS) analysis of the amplicons. Variant allele frequency (VAF) was calculated as FLT3 mutant reads/total FLT3 reads. For pts with multiple FLT3-ITD mutations, the VAF used in analysis was the sum of the VAFs for each FLT3-ITD variant. The lower limit of blank (LOB) of the assay is estimated to be 1 x 10 -6 VAF. For terminology, VAF > 1 x 10 -6 and < 1 x 10 -5 is referred to as MRD6, VAF > 1 x 10 -5 and < 1 x 10 -4 is MRD5, VAF > 1 x 10 -4 or greater is MRD4, and MRD0 equals no detectable MRD. Results: MRD was evaluated in 350/356 (98.3%) pts pre-HCT and 347/356 (97.5%) pts post-HCT. MRD was detected in 46% of pts pre-HCT and 19.9% prior to randomization, including 4.5% who did not have detectable MRD pre-HCT. The variant allele frequency (VAF) of detectable MRD ranged from a low of 1.09 x 10 -6 to a high of 3.0 x 10 -1. More than a single mutation was detected in 51 pts pre-HCT. Most of these 51 pts had 2 clones, but the total ranged from 2-9. The presence of more than one mutation detected as MRD immediately pre-HCT was associated with worse RFS compared with all other pts (MRD-positive with only one clone and MRD-negative), irrespective of treatment arm (Figure 1A; HR=2.428, 95% CI: 1.555, 3.792, P < 0.001). There was no significant difference in age, mutation length, VAF, or karyotype between pts with more than one mutation and those with single mutations. However, if the VAFs of pts with multiple FLT3-ITD mutations were summed and treated as a single value, then the median VAF for pts with multiple mutations was higher than for those with single mutations (2.14 x 10 -4 vs. 3.12 x 10 -5). The VAF (including the summed VAFs of pts with multiple mutations) at multiple levels correlated very closely with RFS after HCT. To illustrate this quantitative effect of peri-HCT FLT3-ITD VAF on RFS, Kaplan-Meier analysis of pts on the placebo arm grouped by MRD level is displayed in Figure 1B. In the 71 pts with MRD detectable post-HCT, the MRD was eradicated in 69% of pts on gilteritinib versus 44% of pts on placebo. Conclusions Pts with multiple FLT3-ITD mutations have a worse prognosis, which may simply be a reflection of increased disease burden (VAF). The quantity of FLT3-ITD MRD appears to highly correlate with outcome. Gilteritinib appears to augment the effect of HCT, as evidenced by increased eradication of MRD post-HCT. These data illustrate the potential utility of the PCR-NGS FLT3-ITD MRD assay in the management of pts with FLT3-ITD AML.

Patient-Reported Outcomes of BMT CTN 1703: A Randomized Phase III Study for Gvhd Prophylaxis - a Quality of Life Evaluation

Introduction A randomized phase III trial of post-transplantation cyclophosphamide (PTCy), tacrolimus, (Tac), and mycophenolate mofetil (MMF) versus tacrolimus/methotrexate (Tac/MTX) for graft-versus-host disease (GVHD) prophylaxis showed superior graft-versus-host disease-free, relapse-free survival (GRFS) in the PTCy-containing arm (NEJM, 2023). Here, we report the effect of GVHD prophylaxis on patient-reported outcomes and impact on quality of life (QOL). Methods The QOL study component of BMT CTN 1703 employed four primary endpoints: Lee Chronic GVHD Symptom Score and the PROMIS subscales of physical function, gastrointestinal symptoms, and satisfaction with participation in social roles. Secondary endpoints included hemorrhagic cystitis symptoms and Lee symptom subscale differences, with questionnaires to English and Spanish-speaking participants at enrollment and on Days 100, 180, and 365 post-transplant. Given the risk of missing assessments, an inverse probability weighted-independent estimating equations (IPW-IEE) model was applied for score comparison between arms, adjusting for baseline score, assessment time, age, donor type, disease risk index (DRI), planned conditioning regimen, and planned use of post-transplant maintenance therapy. Significance was declared at a 1.25% level for score comparisons between arms after Bonferroni correction for multiple testing. The analysis approach classified patients according to the intention-to-treat principle. Results QOL survey completion rates for patients at each timepoint were similar, exceeding 70% in each study arm. With the Lee Chronic GVHD Symptom Scale, higher scores indicate more severe symptoms. The IPW-IEE models indicated that the Lee Chronic GVHD Symptom Scale total scores were significantly lower in the PTCy arm compared to Tac/MTX at day 100 (mean difference [MD] -2.22, 99% confidence interval [CI] -5.05 to 0.61) and day 365 (MD -1.84, 99% CI -5.13 to 1.45, p=0.01 for overall treatment effect across all timepoints, Figure 1). Nutrition subscores were significantly better with PTCy at day 100 (MD -2.41, 99% CI -5.06 to 0.24, p=0.0014). Mouth scores were significantly better in the PTCy arm at day 365 (MD -7.09, 99% CI -13.21 to -0.98, p=0.0035). Patients over 65 years of age had better psychological subscores across the study population (MD -4.80, 99% CI -8.91 to -0.69, p=0.0026); no interaction was found between age and study treatment. Patient-reported hemorrhagic cystitis symptoms showed no significant difference between the study arms at any post-transplant time point. There was no significant treatment effect observed on the 3 PROMIS subscales. Across the entire study population, both relapse and acute GVHD were associated with worse scores on the Lee Symptom Scale, and PROMIS physical function, gastrointestinal symptoms, and social functions subscales. Chronic GVHD was associated with worse scores on the Lee Symptom Scale only, not the PROMIS subscales. No associations were found between patient-reported QOL at baseline and 1-year GRFS, disease-free survival, or overall survival. Conclusions The PTCy arm of BMT CTN 1703 showed superior GRFS, and this study confirms better patient-reported outcomes with PTCy. Patients who received PTCy showed better nutrition and mouth subscores on the Lee Chronic GVHD Symptom Scale compared to those who received Tac/MTX, possibly due to lower observed rates of severe acute and chronic GVHD in the PTCy arm. No association was found between patient-reported baseline quality of life and survival endpoints, suggesting the necessity of further research to elucidate the interplay of treatment strategies, patient factors, and their impact on long-term outcomes.

Comparative analysis of hypomethylating agents as maintenance therapy after allogeneic hematopoietic stem cell transplantation for high-risk acute leukemia

We retrospectively analyzed the outcomes of 136 consecutive patients who received allogeneic hematopoietic stem cell transplantation (allo-HSCT) at our center. Among them, 76 cases used hypomethylating agents (decitabine, n = 40; azacitidine, n = 36) as post-transplant maintenance therapy, whereas 60 contemporaneous patients did not adopt maintenance therapy. The 3-year incidences of relapse in two groups were 16.6% and 39.2% (p = .001). The 3-year OS and DFS in maintenance group were 84.0% and 78.6%, which were remarkably improved than in control group (60.0% and 58.0%) (p = .004, p = .011). Moreover, the 3-year relapse rates for patients receiving decitabine and azacitidine therapy were 8.5% and 25.0%, respectively (p = .019). Patients utilizing decitabine had more common possibility of grade 3–4 neutropenia than azacitidine (20.0% vs. 2.8%, p = .031). These results indicate that maintenance therapies using hypomethylating agents could reduce the risk of post-transplant recurrence, resulting into remarkable superior survival. Decitabine might lower relapse after allo-HSCT with somewhat more severe myelosuppression when being compared to azacitidine.

Outcomes of Autologous Stem Cell Transplantation in Patients with Ultra-High-Risk Multiple Myeloma

Multiple myeloma (MM) patients with high-risk cytogenetic abnormalities have inferior survival outcomes and are underrepresented in clinical trials. There is scarce data on MM patients with more than one high-risk cytogenetic aberration (ie, ultra- high-risk MM). This study was conducted to evaluate outcomes of newly diagnosed MM patients with ultra-high-risk MM who underwent autologous hematopoietic stem cell transplantation (autoHCT). We conducted a retrospective single-center chart review analysis of adult patients with ultra-high-risk MM who underwent autoHCT between 2008 and 2018 at MD Anderson Cancer Center. High-risk cytogenetics were defined as del(17p), t(4;14), t(14;16), or 1q21 gain or amplification (1q+) by fluorescence in situ hybridization. Primary endpoints were progression-free survival (PFS) and overall survival (OS). Seventy-nine patients with two or more high-risk cytogenetic abnormalities were included in our analysis. The median age of 61 years (range, 33.5 to 76.5 years), and 57% were female. Sixty-seven patients had two high-risk cytogenetic abnormalities, and 12 patients had three high-risk cytogenetic abnormalities. The most common combinations of high-risk abnormalities were [1q+, t(4:14)] (n=25; 32%) and [1q+, del17p] (n=21; 27%). The majority of patients received either bortezomib, lenalidomide, and dexamethasone (48%) or carfilzomib, lenalidomide, and dexamethasone (16%) as induction therapy. Prior to autoHCT, 52 patients (66%) achieved a very good partial response or better (≥VGPR), whereas 23 patients (29%) achieved minimal residual disease (MRD)-negative ≥VGPR. Fifty-six patients (71%) received post-transplantation maintenance therapy. Thirty-six patients (46%) achieved MRD-negative ≥VGPR at day +100 after autoHCT, and 40 patients (51%) did so at best post-transplantation response. With a median follow-up in surviving patients of 38.3 months (range, 11.9 to 104.8 months), the median PFS and OS in the entire cohort were 22.9 months and 71.5 months, respectively. For the subset of patients with three HR abnormalities, the median PFS was 15.6 months and median OS was 28.0 months. In multivariate analysis, achieving MRD-negative ≥VGPR prior to autoHCT was associated with improved PFS (hazard ratio [HR], .42; P=.045), whereas male sex (HR, .15; P=.009) and achieving MRD-negative ≥VGPR post-autoHCT (HR, .27; P=.026) were associated with improved OS. In conclusion, patients with ultra-high-risk MM have a median PFS of <24 months with the current standard of care that includes consolidation with autoHCT. These patients may benefit from earlier use of newer treatment modalities, such as chimeric antigen receptor T cell therapy and bispecific antibodies.

Second allogeneic hematopoietic stem cell transplantation with reduced-intensity conditioning and donor changes in relapsed hematological malignancies after the first allogeneic transplant

Objective: The purpose of this study was to assess the safety and efficacy of a second allogeneic hematopoietic stem cell transplantation (allo-HSCT) with reduced-intensity conditioning (RIC) in patients with hematological malignancies who had relapsed after the first allo-HSCT. Methods: Between April 2018 and June 2021, 44 patients with hematological malignancies (B-ALL 23, T-ALL/T-LBL 4, AML15, and MDS 2) were enrolled and retrospectively examined. Unrelated donors (n=12) or haploidentical donors (n=32) were used. Donors were replaced in all patients for the second allo-HSCT. Hematological and immunological germline predisposition genes and hematopoietic and immune function tests were used to select the best-related donor. Total body irradiation (TBI) /fludarabine (FLU) -based (n=38), busulfan (BU) /FLU-based (n=4), total marrow irradiation (TMI) /FLU-based (n=1), and BU/cladribine-based (n=1) were the RIC regimens used. For graft versus host disease (GVHD) prevention, cyclosporine, mycophenolate mofetil, short-term methotrexate, and ATG were used. Eighteen (40.9%) of 44 patients with gene variations for which targeted medications are available underwent post-transplant maintenance therapy. Results: The median age was 25 years old (range: 7-55). The median interval between the first and second HSCT was 19.5 months (range: 6-77). Before the second allo-HSCT, 33 (75%) of the patients were in complete remission (CR), whereas 11 (25%) were not. All patients had long-term engraftment. The grade Ⅱ-Ⅳ GVHD and severe acute GVHD rates were 20.5% and 9.1%, respectively. Chronic GVHD was found in 20.5% of limited patterns and 22.7% of severe patterns. CMV and EBV reactivation rates were 29.5% and 6.8%, respectively. Hemorrhage cystitis occurred in 15.9% of cases, grade Ⅰ or Ⅱ. The 1-yr disease-free survival (DFS), overall survival (OS), and cumulative recurrence incidence (RI) rates of all patients were 72.5% (95% CI, 54.5%-84.3%), 80.6% (95% CI, 63.4%-90.3%), and 25.1% (95% CI, 13.7%-43.2%), respectively, with a median follow-up of 14 (2-39) months. There were eight deaths (seven relapses and one infection). The rate of non-relapse mortality (NRM) was only 2.3%. The CR patients' 1-yr RI rate was significantly lower than the NR patients (16.8% vs 48.1%, P=0.026). The DFS rate in CR patients was greater than in NR patients, although there was no statistical difference (79.9% vs 51.9%, P=0.072). Univariate analysis revealed that CR before the second allo-HSCT was an important prognostic factor. Conclusion: With our RIC regimens, donor change, and post-transplant maintenance therapy, the second allo-HSCT in relapsed hematological malignancies after the first allo-HSCT is a safe and effective treatment with high OS and DFS and low NRM and relapse rate. The most important factor influencing the prognosis of the second allo-HSCT is the patient's illness condition before the transplant.

Bridging to transplant and post-transplant maintenance therapy with FLT3 inhibitors in patients with relapsed or refractory FLT3 mutated acute myeloid leukemia

ABSTRACTObjectives and MethodsThis single-center retrospective study was performed to evaluate the safety and efficacy of FMS-like tyrosine kinase 3 (FLT3) inhibitors before and after allogeneic hematopoietic cell transplantation (HCT) in relapsed/refractory patients with FLT3-mutation positive acute myeloid leukemia (AML).ResultsTen patients who met the eligibility criteria were included. Eight of them achieved hematological remission at HCT, within a median span of 79 days (range: 43–197). In post-HCT, patients started maintenance therapy (MT; median time-to-start 79 days, range: 43–197), and the median duration of MT was 390 days (range: 67–815). Grade 3 hematological adverse events (AEs) were found in two patients, and non-hematological AEs were found in five patients. Nine patients underwent either dose reduction, discontinuation of therapy, or a switch to another FLT3 inhibitor due to AEs. Disease relapse occurred in one patient during MT. At the time of the last follow-up, seven patients are alive and disease-free, while three have died due to infection or transplant complications.ConclusionIn relapsed/refractory FLT3 mutation-positive AML, the use of FLT3 inhibitors can lead to high response rates and provide a safe bridge from HCT to MT. If sufficient attention is paid to safety, this therapy is expected to prevent disease relapse even with reduced dosages.

Post-transplant maintenance therapy in acute myeloid leukemia after allogeneic hematopoietic stem cell transplantation harmonizing multiple therapeutic modalities including targeted therapy, immunotherapy and cellular therapy.

Allogeneic hematopoietic stem cell transplant (HCT) has improved survival for patients with acute myeloid leukemia (AML), especially for those at high risk of relapse. However, relapse remains the leading cause of treatment failure post-HCT, occurring in around 35-45% of patients, and leading to dismal outcomes. Strategies to reduce relapse risk are urgently needed, especially in the early post-transplant period before activation of the graft-versus-leukemia (GVL) effect. Maintenance therapy is a course of treatment given post-HCT with the expectation of reducing relapse risk. While there are currently no therapies approved for maintenance therapy for AML after HCT, there are a number of studies and ongoing investigations examining the role of maintenance therapies that include targeted agents against FLT3-ITD, BCL2, or IDH mutations, hypomethylating agents, immunomodulatory therapies and cellular therapies. In this review, we discuss the mechanistic and clinical data for post-transplant maintenance therapies in AML and strategies for maintenance therapy for AML after HCT.

A retrospective study of autologous hematopoietic stem cell transplantation for peripheral T-cell lymphoma: pre-transplant patients with partial remission benefit from post-transplant maintenance therapy.

Whether autologous hematopoietic stem cell transplantation (ASCT) improves the survival of patients with peripheral T-cell lymphoma (PTCL) remains controversial. Some studies have demonstrated that the efficacy of ASCT is superior in patients with complete remission (CR), whereas patients with partial remission (PR) remain vulnerable to relapse after ASCT, resulting in decreased survival rates. Maintenance therapy after chemotherapy may reduce the relapse rate of PTCL and improve survival; however, the role of maintenance therapy after ASCT in PTCL remains unclear. In this study, we aimed to analyze the efficacy of ASCT and post-transplant maintenance therapy in PTCL. We retrospectively analyzed the clinical data of 69 patients with PTCL who underwent ASCT at our center between November 2001 and November 2021. According to the patients' intention, thirty patients received post-transplant maintenance treatment, whereas 39 did not. The overall survival (OS) and progression-free survival (PFS) between the groups were compared using the log-rank test. At a median follow-up of 36 months, the entire cohort's 3-year OS and PFS were 67.8% and 53.0%, respectively. The 3-year OS and PFS of patients with CR1, CR2, and PR were 85.3% and 65.4%, 80.0% and 60.0%, and 38.4% and 32.0%, respectively (OS: P=0.001; PFS: P=0.003). The relapse rates between the groups with or without maintenance therapy were 26.7% vs. 52.2%, the 3-year OS was 86.0% vs. 54.2% (P=0.004), and the 3-year PFS was 73.3% vs. 37.5% (P=0.004). Further analysis revealed that the efficacy of maintenance therapy was not significant in patients with CR1 and CR2, whereas patients with PR benefited from maintenance therapy. The relapse rate of patients with PR who received or did not receive maintenance therapy was 33.3% vs. 78.7%, 3-year OS was 66.7% vs. 21.9% (P=0.007), and 3-year PFS was 66.7% vs. 12.5% (P=0.004). Patients with CR in PTCL benefit from ASCT, and post-transplant maintenance therapy reduces the relapse rate and significantly improves OS and PFS in patients with PR.

Venetoclax is safe and tolerable as post-transplant maintenance therapy for AML patients at high risk for relapse.

Relapse is the most common cause of mortality in acute myeloid leukemia (AML) patients after allogeneic stem cell transplant (SCT). Post-SCT maintenance strategies that prevent relapse are desirable but must be well tolerated and convenient to administer. We hypothesized single agent venetoclax (ven) may be an effective maintenance therapy among high relapse risk patients. Between February 2019 and December 2021, we administered post-SCT ven maintenance to 49 AML patients at high-risk for relapse as a prospectively defined off-label practice at our institution. Ven was planned to be administered until 1-year post-SCT. While temporary interruptions were common (67.3% of all patients), of those with >1 year follow up, 22/25 (88%) completed the full year of planned therapy. Cytopenias (40.8%) and gastrointestinal adverse events (34.7%) were the most common toxicities. At 1-year post-SCT, overall survival (OS) and relapse-free survival (RFS) were 70% and 67% respectively. Our experience demonstrates single agent ven is a safe, tolerable, and feasible maintenance therapy that may improve RFS and OS in high relapse risk post-SCT patients.

Overcoming relapse: prophylactic or pre-emptive use of azacitidine or FLT3 inhibitors after allogeneic transplantation for AML or MDS.

Relapse remains the most critical obstacle in treatment by allogeneic hematopoietic stem cell transplantation (HSCT). Non-relapse mortality has improved annually, but relapse mortality remains high. Post-transplant maintenance treatment, such as hypomethylating agents and FMS-like tyrosine kinase 3 (FLT3) inhibitors, has been investigated for decades as a means of preventing disease relapse after HSCT. Other factors besides the relapse tendency of the primary disease that can affect the transition of estimated disease burden in patients undergoing HSCT are disease status at HSCT (non-remission, remission with minimal/measurable residual disease (MRD), and remission without MRD) and conditioning regimen intensity. Optimal selection of patients at high risk for relapse who can tolerate a long duration of therapy is pivotal for successful post-transplant maintenance therapy. In this review, we provide an overview of current progress in research on post-transplant maintenance treatment using azacitidine or FLT3 inhibitors for preventing disease relapse after HSCT for AML or MDS, and discuss the future outlook in this area.