RAS-mutant leukaemia stem cells drive clinical resistance to venetoclax.

Cancer driver mutations often show distinct temporal acquisition patterns, but the biological basis for this, if any, remains unknown. RAS mutations occur invariably late in the course of acute myeloid leukaemia, upon progression or relapsed/refractory disease1-6. Here, by using human leukaemogenesis models, we first show that RAS mutations are obligatory late events that need to succeed earlier cooperating mutations. We provide the mechanistic explanation for this in a requirement for mutant RAS to specifically transform committed progenitors of the myelomonocytic lineage (granulocyte-monocyte progenitors) harbouring previously acquired driver mutations, showing that advanced leukaemic clones can originate from a different cell type in the haematopoietic hierarchy than ancestral clones. Furthermore, we demonstrate that RAS-mutant leukaemia stem cells (LSCs) give rise to monocytic disease, as observed frequently in patients with poor responses to treatment with the BCL2 inhibitor venetoclax. We show that this is because RAS-mutant LSCs, in contrast to RAS-wild-type LSCs, have altered BCL2 family gene expression and are resistant to venetoclax, driving clinical resistance and relapse with monocytic features. Our findings demonstrate that a specific genetic driver shapes the non-genetic cellular hierarchy of acute myeloid leukaemia by imposing a specific LSC target cell restriction and critically affects therapeutic outcomes in patients.

Venetoclax abrogates the prognostic impact of splicing factor gene mutations in newly diagnosed acute myeloid leukemia.

Mutations in splicing factor (SF) genes SRSF2, U2AF1, SF3B1, and ZRSR2 are now considered adverse risk in the European LeukemiaNet 2022 acute myeloid leukemia (AML) risk stratification. The prognostic impact of SF mutations in AML has been predominantly derived from younger patients treated with intensive (INT) therapy. We evaluated 994 patients with newly diagnosed AML, including 266 (27%) with a SFmut. Median age was 67 years overall, with patients with SFmut being older at 72 years. SRSF2 (n = 140, 53%) was the most common SFmut. In patients treated with INT, median relapse-free survival (RFS) (9.6 vs 21.4 months, P = .04) and overall survival (OS) (15.9 vs 26.7 months, P = .06) were shorter for patients with SFmut than without SFwt, however this significance abrogated when evaluating patients who received venetoclax with INT therapy (RFS 15.4 vs 20.3 months, P = .36; OS 19.6 vs 30.7 months, P = .98). In patients treated with LI, median RFS (9.3 vs 7.7 months, P = .35) and OS (12.3 vs 8.5 months, P = .14) were similar for patients with and without SFmut , and outcomes improved in all groups with venetoclax. On multivariate analysis, SFmut did not affect hazards of relapse and death for INT arm but reduced both these hazards in LI arm. In a large AML data set with >60% of patients receiving venetoclax with LI/INT therapy, SFmut had no independent negative prognostic impact. Newer prognostic models that consider LI therapy and use of venetoclax among other factors are warranted.

Preclinical characterization of ISB 1342, a CD38 × CD3 T-cell engager for relapsed/refractory multiple myeloma.

Although treatment of multiple myeloma (MM) with daratumumab significantly extends the patient's lifespan, resistance to therapy is inevitable. ISB 1342 was designed to target MM cells from patients with relapsed/refractory MM (r/r MM) displaying lower sensitivity to daratumumab. ISB 1342 is a bispecific antibody with a high-affinity Fab binding to CD38 on tumor cells on a different epitope than daratumumab and a detuned scFv domain affinity binding to CD3ε on T cells, to mitigate the risk of life-threatening cytokine release syndrome, using the Bispecific Engagement by Antibodies based on the TCR (BEAT) platform. In vitro, ISB 1342 efficiently killed cell lines with different levels of CD38, including those with a lower sensitivity to daratumumab. In a killing assay where multiple modes of action were enabled, ISB 1342 showed higher cytotoxicity toward MM cells compared with daratumumab. This activity was retained when used in sequential or concomitant combinations with daratumumab. The efficacy of ISB 1342 was maintained in daratumumab-treated bone marrow patient samples showing lower sensitivity to daratumumab. ISB 1342 induced complete tumor control in 2 therapeutic mouse models, unlike daratumumab. Finally, in cynomolgus monkeys, ISB 1342 displayed an acceptable toxicology profile. These data suggest that ISB 1342 may be an option in patients with r/r MM refractory to prior anti-CD38 bivalent monoclonal antibody therapies. It is currently being developed in a phase 1 clinical study.

Electronic States of Single Perovskite Quantum Dots in Weak and Strong Interaction Regimes: Implications in Electrically Pumped Quantum Emitters.

We investigate the effect of Coulomb interactions on the electronic states of a single perovskite quantum dot (PQD), CsPbBr3, through scanning tunneling microscopy/spectroscopy (STM/S). Under a weak interaction regime, where the time-averaged occupation of electrons in a PQD remains zero, the peaks observed in the differential tunneling conductance (dI/dV) spectrum correspond to the single-particle density of states (DOS) without any electron-electron correlation. However, with a shorter tunnel distance between the STM tip and PQD, additional electrons are trapped in the QD, leading to a strong interaction regime with well-defined electronic fine structures due to the lifting of spin degeneracy in the conduction bands. Interestingly, we observe that the strong Coulomb interaction can modify the spin-orbit coupling (SOC) strength in the PQDs. We have concluded that the energy levels under a strong electron-electron interaction regime are of utmost importance since they will be applicable to electrically pumped PQD-based single photon quantum emitters.

Outcomes and genetic dynamics of acute myeloid leukemia at first relapse.

Patients with relapsed acute myeloid leukemia (rAML) experience dismal outcomes. We performed a comprehensive analysis of patients with rAML to determine the genetic dynamics and survival predictive factors. We analyzed 875 patients with newly diagnosed AML who received intensive treatment (IT) or low-intensity treatment (LIT). Of these patients, 197 experienced subsequent rAML. Data was available for 164 patients, with a median time from CR/CRi to relapse of 6.5 months. Thirty-five of the 164 patients (21%) experienced relapse after allogeneic hematopoietic stem cell transplantation (alloSCT). At relapse mutations in genes involved in pathway signaling tended to disappear, whereas clonal hematopoiesis-related mutations or TP53 tended to persist. Patients with normal karyotypes tended to acquire cytogenetic abnormalities at relapse. Patients treated with IT had a higher emergence rate of TP53 mutations (16%), compared to patients treated with LIT (1%, P = 0.009). The overall response rates were 38% and 35% for patients treated with salvage IT or LIT, respectively. Seventeen patients (10%) underwent alloSCT after salvage therapy. The median overall survival (OS) duration after relapse was 5.3 months, with a 1-year OS rate of 17.6%. Complex karyotype (hazard ratio [HR] = 2.14, P < 0.001), a KMT2A rearrangement (HR = 3.52, P = 0.011), time in remission < 12 months (HR = 1.71, P = 0.011), and an elevated white blood cell count at relapse (HR = 2.38, P = 0.005) were independent risk factors for OS duration. More effective frontline and maintenance therapies are warranted to prevent rAML.

Targetable genetic abnormalities in patients with acute myeloblastic leukemia across age groups.

Incidence of potential targetable genetic abnormalities by age in AML.

Triple combination targeting methyltransferase, BCL-2, and PD-1 facilitates antileukemia responses in acute myeloid leukemia.

BACKGROUND: A recent breakthrough therapy combining the BCL-2 inhibitor venetoclax with hypomethylating agents (HMAs) targeting DNA methyltransferase has improved outcomes for patients with acute myeloid leukemia (AML), but the responses and long-term survival in older/unfit patients and in patients with relapsed/refractory AML remain suboptimal. Recent studies showed that inhibition of BCL-2 or DNA methyltransferase modulates AML T-cell immunity. METHODS: By using flow cytometry and time-of-flight mass cytometry, the authors examined the effects of the HMA decitabine combined with the BCL-2 inhibitor venetoclax (DAC/VEN therapy) on leukemia cells and T cells in patients with AML who received DAC/VEN therapy in a clinical trial. The authors investigated the response of programmed cell death protein 1 (PD-1) inhibition in the DAC/VEN-treated samples in vitro and investigated the triple combination of PD-1 inhibition with HMA/venetoclax in the trial patients who had AML. RESULTS: DAC/VEN therapy effectively targeted leukemia cells and upregulated the expression of the immune checkpoint-inhibitory receptor PD-1 in T cells while preserving CD4-positive and CD8-positive memory T cells in a subset of patients with AML who were tested. In vitro PD-1 inhibition potentiated the antileukemia response in DAC/VEN-treated AML samples. The combined use of azacitidine, venetoclax, and nivolumab eliminated circulating blasts and leukemia stem cells/progenitor cells and expanded the percentage of CD8-positive memory T cells in an illustrative patient with relapsed AML who responded to the regimen in an ongoing clinical trial. CONCLUSIONS: Immunomodulation by targeting PD-1 enhances the therapeutic effect of combining an HMA and venetoclax in patients with AML.

Comparison of Mold Active Triazoles as Primary Antifungal Prophylaxis in Patients With Newly Diagnosed Acute Myeloid Leukemia in the Era of Molecularly Targeted Therapies.

BACKGROUND: Multiple factors influence the choice of primary antifungal prophylaxis (PAP) in patients with acute myeloid leukemia (AML) undergoing remission induction chemotherapy (RIC) given the recent incorporation of targeted leukemia therapies into these regimens. METHODS: We evaluated the incidence and characteristics of breakthrough invasive fungal infections (bIFI) in 277 adult patients with newly diagnosed AML undergoing RIC with high-intensity, or low-intensity venetoclax-containing therapy. Patients receiving posaconazole (PCZ), voriconazole (VCZ), or isavuconazole (ISA) for > 5 days as PAP during RIC were included. Echinocandin use prior to, but not concomitantly with, the PAP azole was allowed. IFI (modified EORTC/MSG criteria) occurring after > 5 days of continuous azole exposure or within 14 days of discontinuation were considered bIFI. RESULTS: Proven or probable bIFI were observed in 11 patients (4%). The incidence of bIFI was 2.9% for PCZ, 4.8% for VCZ, and 5.7% for ISA (P = .55). In total, 161 patients (58%) received echinocandin prophylaxis prior to azole initiation. Neither echinocandin exposure nor chemotherapy intensity impacted bIFI rate. Patients with bIFI had a lower rate of absolute neutrophil count recovery > 1000 cells/µL (64% vs 90%, P = .021) or complete remission (CR; 18% vs 66%, P = .002) after RIC. Thirty-eight patients (14%) discontinued PAP due to toxicity, most often hepatotoxicity. Discontinuation due to hepatotoxicity was similar among azoles (PCZ: 13%; VCZ: 15%; ISA: 13%). CONCLUSIONS: The rate of bIFI is low during RIC in patients with newly diagnosed AML receiving any of the mold-active triazoles as PAP. Neutrophil recovery and achievement of CR are important for bIFI risk.

Carrier recombination in CH3NH3PbI3: why is it a slow process?

In methylammonium lead iodide (MAPbI3), a slow recombination process of photogenerated carriers has often been considered to be the most intriguing property of the material resulting in high-efficiency perovskite solar cells. In spite of intense research over a decade or so, a complete understanding of carrier recombination dynamics in MAPbI3has remained inconclusive. In this regard, several microscopic processes have been proposed so far in order to explain the slow recombination pathways (both radiative and non-radiative), such as the existence of shallow defects, a weak electron-phonon coupling, presence of ferroelectric domains, screening of band-edge charges through the formation of polarons, occurrence of the Rashba splitting in the band(s), and photon-recycling in the material. Based on the up-to-date findings, we have critically assessed each of these proposals/models to shed light on the origin of a slow recombination process in MAPbI3. In this review, we have presented the interplay between the mechanisms and our views/perspectives in determining the likely processes, which may dictate the recombination dynamics in the material. We have also deliberated on their interdependences in decoupling contributions of different recombination processes.

Clinical outcomes and impact of therapeutic intervention in patients with acute myeloid leukemia who experience measurable residual disease (MRD) recurrence following MRD-negative remission.

Recurrence of MRD in AML is associated with imminent relapse unless intervened upon. Change in chemotherapy regimen and/or immediate transplant improve outcomes.

Differential prognostic impact of RUNX1 mutations according to frontline therapy in patients with acute myeloid leukemia.

RUNX1-mutated (mRUNX1) acute myeloid leukemia (AML) has historically been associated with poor outcomes in the setting of conventional chemotherapy. The prognostic impact of mRUNX1 AML is not well-established in the current era of lower-intensity treatment regimens incorporating venetoclax. We retrospectively analyzed 907 patients with newly diagnosed AML, including 137 patients with mRUNX1 AML, who underwent first-line therapy with intensive chemotherapy (IC), low-intensity therapy without venetoclax (LIT without VEN), or LIT with VEN. When stratified by RUNX1 status, there was no statistically significant difference in outcomes between mRUNX1 and wild-type (wtRUNX1) AML, regardless of therapy received. However, among patients who received LIT with VEN, there was a trend towards superior overall survival (OS) in those with mRUNX1 AML (median OS for mRUNX1 vs. wtRUNX1: 25.1 vs. 11.3 months; 2-year OS 54% vs. 33%; p = 0.12). In patients without another adverse-risk cyto-molecular feature, the presence of mRUNX1 conferred inferior OS in patients who received IC (p = 0.02) or LIT without VEN (p = 0.003) but not in those who received LIT with VEN (mRUNX1 vs. wtRUNX1: 25.1 vs. 30.0 months; 2-year OS 59% vs. 54%; p = 0.86). A multivariate analysis showed possible interaction between RUNX1 mutation status and treatment, suggesting a differential prognostic impact of RUNX1 mutations when patients received IC versus LIT with VEN. In summary, the prognostic impact of mRUNX1 AML may be treatment-dependent, and the presence of RUNX1 mutations may not impact clinical outcomes when venetoclax-based regimens are used.

Contemporary outcomes in IDH-mutated acute myeloid leukemia: The impact of co-occurring NPM1 mutations and venetoclax-based treatment.

Isocitrate dehydrogenase 1 or 2 (IDH1 or IDH2) mutations occur frequently in newly diagnosed (ND) acute myeloid leukemia (AML) often with co-occurring NPM1 mutations, which may influence treatment outcomes. Detailed analysis of IDH-mutated AML treated with venetoclax and influence of co-occurring NPM1 mutations remains unclear. This retrospective single-center cohort study evaluated clinical and molecular demographics,response and survival, and impact of co-occurring NPM1 mutations in patients with IDH1 or IDH2-mutated AML. 556 patients with IDH1, IDH2, and/or NPM1 mutated AML were included. Patients with IDH1mut AML (N = 119) were more likely to have older age, sAML, ELN-adverse risk disease, and adverse-risk cytogenetics compared to those with IDH2mut (N = 229) or IDHwt /NPM1mut AML (N = 208). In multivariate analysis, patients with IDH2mut (HR 0.61 [95%CI: 0.43-0.88], p value: .007) or IDHwt /NPM1mut (HR 0.65 [95% CI: 0.45-0.94], p value: .024) AML had a decreased risk of death versus IDH1mut AML. Venetoclax-based lower-intensity regimens partially abrogated the detrimental effect of IDH1mut with similar OS observed between IDH1mut /NPM1wt , IDH2mut /NPM1wt , and IDHwt /NPM1mut AML. With regards to the influence of IDHmut /NPM1mut cases, IC improved survival in IDH2mut /NPM1mut versus IDH2mut /NPM1wt AML (HR: 0.54 [95% CI: 0.2644-1.082], p value: .077), while venetoclax-based therapy improved survival in IDH1mut /NPM1mut versus IDH1mut /NPM1wt AML (HR: 0.094 [95% CI: 0.01-0.74], p value: .0056). Differing outcomes were observed in IDH1mut versus IDH2mut or NPM1mut AML which were influenced by co-occurring NPM1 mutations and partially abrogated with venetoclax-based therapy. Given the differing biology and survival in IDH1mut AML, investigations incorporating molecularly targeted therapies such as IDH inhibitors remain warranted in this subgroup.

Venetoclax combined with FLAG-IDA induction and consolidation in newly diagnosed acute myeloid leukemia.

Multi-agent induction chemotherapy (IC) improves response rates in younger patients with acute myeloid leukemia (AML); however, relapse remains the principal cause of treatment failure. Improved induction regimens are needed. A prospective single-center phase Ib/II study evaluating fludarabine, cytarabine, G-CSF, and idarubicin combined with venetoclax (FLAG-IDA + VEN) in patients with newly diagnosed (ND) or relapsed/refractory AML. The primary efficacy endpoint was assessment of overall activity (overall response rate [ORR]: complete remission [CR] + CR with partial hematologic recovery [CRh] + CR with incomplete hematologic recovery [CRi] + morphologic leukemia free state + partial response). Secondary objectives included additional assessments of efficacy, overall survival (OS), and event-free survival (EFS). Results of the expanded ND cohort with additional follow-up are reported. Forty-five patients (median age: 44 years [range 20-65]) enrolled. ORR was 98% (N = 44/45; 95% credible interval 89.9%-99.7%). Eighty-nine percent (N = 40/45) of patients attained a composite CR (CRc + CRh + CRi) including 93% (N = 37/40) who were measurable residual disease (MRD) negative. Twenty-seven (60%) patients transitioned to allogeneic stem cell transplant (alloHSCT). Common non-hematologic adverse events included febrile neutropenia (44%; N = 20), pneumonia (22%, N = 10), bacteremia (18%, N = 8), and skin/soft tissue infections (44%, N = 20). After a median follow-up of 20 months, median EFS and OS were not reached. Estimated 24-month EFS and OS were 64% and 76%, respectively. FLAG-IDA + VEN is an active regimen in ND-AML capable of producing high MRD-negative remission rates and enabling transition to alloHSCT when appropriate in most patients. Toxicities were as expected with IC and were manageable. Estimated 24-month survival appears favorable compared to historical IC benchmarks.

A Phase II Study of Azacitidine, Venetoclax, and Trametinib in Relapsed or Refractory Acute Myeloid Leukemia Harboring RAS Pathway-Activating Mutations.

INTRODUCTION: RAS pathway mutations are common mechanisms of resistance to acute myeloid leukemia (AML) therapies. Trametinib, an oral MEK inhibitor, has been shown to have single-agent activity in relapsed/refractory AML and preclinical synergy with venetoclax. METHODS: We conducted a single-center, open-label, phase 2 trial of the combination of azacitidine, venetoclax, and trametinib in patients with relapsed or refractory AML harboring a RAS pathway-activating mutation. RESULTS: Sixteen patients were treated. The patients were heavily pretreated with a median number of 4 prior therapies; 13 (81%) had received a prior hypomethylating agent (HMA) with venetoclax, and 8 (50%) had undergone prior stem cell transplant. Four patients (25%) responded (CR, n = 1; CRi, n = 1; MLFS, n = 2). Two of the 3 patients (67%) who had not previously received HMA plus venetoclax responded; in contrast, only 2 of the 13 patients (15%) who had previously received HMA plus venetoclax responded. The median OS was 2.4 months, and the 6-month OS rate was 31%. Related grade 3-4 adverse events occurred in 50% of patients, and 50% of patients required a dose adjustment of trametinib. CONCLUSIONS: The combination of azacitidine, venetoclax, and trametinib had only modest activity in patients with relapsed/refractory AML, with a response rate that was similar to previous reports of trametinib monotherapy. Substantial toxicity was observed with this combination. Given the established role of RAS pathway mutations in mediating resistance to AML therapies, future studies of better tolerated, more active inhibitors of this pathway are still needed.

Spin-Selective Charge Transport in Lead-Free Chiral Perovskites: The Key towards High-Anisotropy in Circularly-Polarized Light Detection.

A pair of zero-dimensional lead-free chiral perovskites is introduced towards the detection of circularly polarized light (CPL). Although spin-polarized carriers are generated in the perovskites under the CPL, the absorption anisotropy remained low leading to mostly similar density of photogenerated carriers under the two CPLs. Interestingly, due to the intrinsic chirality in the perovskites, they exhibited chirality-induced spin-selectivity (CISS) allowing the transport of only one type of spin-half states. A high anisotropy in photocurrent along the out-of-plane direction has therefore appeared resulting in a spin-dependent photovoltaic effect in vertical heterojunction devices and making them suitable for CPL detection. While a self-powered CPL detector showed a limited (but one of the highest to date) anisotropy factor of 0.3 due to possible spin-flips during the transport process, the factor rose to 0.6 under bias prompting extension of the effective spin-diffusion length.

Outcomes of TP53-mutant acute myeloid leukemia with decitabine and venetoclax.

BACKGROUND: TP53 mutation (TP53mut ) confers an adverse prognosis in acute myeloid leukemia (AML). Venetoclax with hypomethylating agents is a current standard for older patients; however, recent reports suggest that TP53mut confers resistance to venetoclax. The authors investigated the outcomes of patients with TP53mut AML who were treated with a 10-day decitabine and venetoclax (DEC10-VEN) (ClinicalTrials.gov identifier NCT03404193). METHODS: Patients with newly diagnosed AML received decitabine 20 mg/m2 for 10 days every 4 to 6 weeks for induction, followed by decitabine for 5 days after response. The venetoclax dose was 400 mg daily. TP53mut was identified in bone marrow samples using next-generation sequencing, with sensitivity of 5%. Outcomes were analyzed according to European LeukemiaNet 2017 guidelines. RESULTS: Among 118 patients (median age, 72 years; age range, 49-89 years), 63 (53%) had secondary AML, 39 (33%) had AML with complex karyotype, and 35 (30%) had TP53mut AML. The median TP53 variant allele frequency was 32% (interquartile range, 16%-65%), 8 patients (23%) had only a single TP53 mutation, 15 (43%) had multiple mutations, and 12 (34%) had mutation and deletion. Outcomes were significantly worse in patients who had TP53mut AML compared with those who had wild-type TP53 AML, with an overall response rate of 66% vs 89% (P = .002), a complete response/complete response with incomplete hematologic recovery rate of 57% vs 77% (P = .029), and a 60-day mortality of 26% vs 4% (P < .001), respectively. Patients with TP53mut versus wild-type TP53 had shorter overall survival at 5.2 versus 19.4 months, respectively (hazard ratio, 4.67; 95% CI, 2.44-8.93; P < .0001), and shorter relapse-free survival at 3.4 versus 18.9 months (hazard ratio, 4.80; 95% CI, 1.97-11.69; P < .0001), respectively. Outcomes with DEC10-VEN in patients with TP53mut AML were comparable to historical results with 10-day decitabine alone. CONCLUSIONS: Patients with TP53mut AML have lower response rates and shorter survival with DEC10-VEN.

Duration of cytopenias with concomitant venetoclax and azole antifungals in acute myeloid leukemia.

BACKGROUND: Venetoclax (VEN) combined with the hypomethylating agent (HMA) azacitidine improves survival in patients aged ≥75 years with newly diagnosed acute myeloid leukemia (AML). VEN and HMA treatment can result in prolonged and often profound neutropenia, and this warrants antifungal prophylaxis. Azole antifungals inhibit cytochrome P450 3A4, the primary enzyme responsible for VEN metabolism; this results in VEN dose reductions for each concomitant antifungal. Limited clinical data exist on outcomes for patients treated with VEN, an HMA, and various azoles. METHODS: The time to neutrophil recovery (absolute neutrophil count [ANC] > 1000 cells/mm3 ) and platelet (PLT) recovery (PLT count > 100,000 cells/mm3 ) in 64 patients with newly diagnosed AML who achieved a response after course 1 of VEN plus an HMA were evaluated. HMA therapy included azacitidine (75 mg/m2 intravenously/subcutaneously for 7 days) or decitabine (20 mg/m2 intravenously for 5 or 10 days). RESULTS: Forty-seven patients (73%) received an azole: posaconazole (n = 17; 27%), voriconazole (n = 9; 14%), isavuconazole (n = 20; 31%), or fluconazole (n = 1; 2%). The median time to ANC recovery were similar for patients who did receive an azole (37 days; 95% confidence interval [CI], 34-38 days) and patients who did not receive an azole (39 days; 95% CI, 30 days to not estimable; P = .8). The median time to PLT recovery was significantly longer for patients receiving azoles (28 vs 22 days; P = .01). The median times to ANC recovery (35 vs 38 days) and PLT recovery (26 vs 32 days) were similar with posaconazole and voriconazole. CONCLUSIONS: VEN plus an HMA resulted in neutropenia and thrombocytopenia, with the latter prolonged in patients receiving concomitant azoles. Concomitant posaconazole or voriconazole and VEN (100 mg) resulted in similar ANC and PLT recovery times, suggesting the safety of these dosage combinations during course 1.

Ten-day decitabine with venetoclax versus intensive chemotherapy in relapsed or refractory acute myeloid leukemia: A propensity score-matched analysis.

BACKGROUND: Relapsed/refractory (R/R) acute myeloid leukemia (AML) has poor outcomes. Although lower-intensity venetoclax-containing regimens are standard for older/unfit patients with newly diagnosed AML, it is unknown how such regimens compare with intensive chemotherapy (IC) for R/R AML. METHODS: Outcomes of R/R AML treated with 10-day decitabine and venetoclax (DEC10-VEN) were compared with IC-based regimens including idarubicin with cytarabine, with or without cladribine, clofarabine, or fludarabine, with or without additional agents. Propensity scores derived from patient baseline characteristics were used to match DEC10-VEN and IC patients to minimize bias. RESULTS: Sixty-five patients in the DEC10-VEN cohort were matched to 130 IC recipients. The median ages for the DEC10-VEN and IC groups were 64 and 58 years, respectively, and baseline characteristics were balanced between the 2 cohorts. DEC10-VEN conferred significantly higher responses compared with IC including higher overall response rate (60% vs 36%; odds ratio [OR], 3.28; P < .001), complete remission with incomplete hematologic recovery (CRi, 19% vs 6%; OR, 3.56; P = .012), minimal residual disease negativity by flow cytometry (28% vs 13%; OR, 2.48; P = .017), and lower rates of refractory disease. DEC10-VEN led to significantly longer median event-free survival compared with IC (5.7 vs 1.5 months; hazard ratio [HR], 0.46; 95% CI, 0.30-0.70; P < .001), as well as median overall survival (OS; 6.8 vs 4.7 months; HR, 0.56; 95% CI, 0.37-0.86; P = .008). DEC10-VEN was independently associated with improved OS compared with IC in multivariate analysis. Exploratory analysis for OS in 27 subgroups showed that DEC10-VEN was comparable with IC as salvage therapy for R/R AML. CONCLUSION: DEC10-VEN represents an appropriate salvage therapy and may offer better responses and survival compared with IC in adults with R/R AML.

Inotuzumab ozogamicin with bosutinib for relapsed or refractory Philadelphia chromosome positive acute lymphoblastic leukemia or lymphoid blast phase of chronic myeloid leukemia.

Relapsed/refractory (R/R) Philadelphia chromosome positive acute lymphoblastic leukemia (Ph + ALL) and lymphoid blast phase of chronic myeloid leukemia (LBP-CML) have poor outcomes. We designed a phase 1/2 study combining inotuzumab ozogamicin with bosutinib for this patient population. Patients with T315I mutation were excluded. Bosutinib was administered daily at three dose levels (300 mg/d, 400 mg/d, 500 mg/d) in a 3 + 3 design. Inotuzumab ozogamicin was dosed weekly during cycle one, and once every 4 weeks subsequently for a total of six cycles. The primary objective was to determine the safety and the maximum tolerated dose (MTD) of bosutinib in combination with inotuzumab ozogamicin. Eighteen patients were enrolled (Ph-positive ALL, n = 16; LBP-CML, n = 2). The median age was 62 years (range, 19-74) and the median number of prior therapies was one (range, 1-5). Dose limiting toxicities included grade 3 skin rash and bosutinib 400 mg daily was determined as the MTD. The most frequent grade 3/4 treatment-emergent adverse events were thrombocytopenia (60%) and neutropenia (38%). A complete response (CR) / CR with incomplete count recovery (CRi) was achieved in 15/18 (83%) patients; 11/18 (61%) patients achieved negative measurable residual disease by flow cytometry. Complete molecular response was noted in 10/18 (56%) patients. The 30-day mortality was 0%. After a median follow-up of 44 months, the median duration of response and overall survival were 7.7 months and 13.5 months, respectively. Six patients had a subsequent allogeneic stem cell transplant. No patient developed veno-occlusive disease. Inotuzumab ozogamicin with bosutinib was well tolerated in R/R Ph-positive ALL and LBP-CML.

Outcome of T-cell acute lymphoblastic leukemia/lymphoma: Focus on near-ETP phenotype and differential impact of nelarabine.

Early T-cell precursor acute lymphoblastic leukemia/lymphoma (ETP-ALL/LBL) is characterized by a distinct immunophenotype (CD1a-negative, CD8-negative, CD5-negative or weak-positive <75%, myeloid/stem-cell markers positive) and poor clinical outcomes. Near-ETP ALL is transcriptionally similar to ETP-ALL but CD5 expression level is not low enough to meet the criteria of ETP immunophenotype. Outcomes of near-ETP ALL are not well characterized. We reviewed 171 patients with newly-diagnosed T-ALL/LBL. Patients were categorized into three groups; ETP (N = 27), near-ETP (N = 24), and non-ETP ALL/LBL (N = 120). ETP-ALL/LBL was associated with a significantly worse survival compared with non-ETP ALL/LBL: 5-year overall survival (OS) rates 32% versus 63% (p < .001). Outcome was similar between near-ETP and non-ETP ALL/LBL: 5-year OS rates 56% versus 63% (p = .543). Landmark analysis showed that allogeneic stem cell transplant (allo-SCT) in first remission was beneficial in ETP-ALL/LBL (5-year event-free survival rates 36% versus 18%, p = .030) but not in near-ETP or non-ETP ALL/LBL. Multivariate analysis selected the following as significant independent prognostic factors for OS: age ≥ 60 years (HR 3.11; p = .003); elevated WBC ≥100 × 109 /L (HR 2.60; p = .005); and ETP immunophenotype (HR 2.29; p = .010). A survival advantage with adding nelarabine to hyper-CVAD was observed in non-ETP ALL (5-year OS rates 83% versus 38% with hyper-CVAD plus neralabine versus hyper-CVAD, p = .003). In conclusion, outcome of ETP-ALL/LBL was poor and improved with allo-SCT; outcome of near-ETP ALL/LBL was similar to non-ETP ALL/LBL; the addition of nelarabine to hyper-CVAD improved the survival in non-ETP ALL only.