Transplant Outcomes in Myelofibrosis: Impact of Donor Type [Cord Blood Grafts Supported by CD34+ selected Cells (Haplo-Cord) vs Matched Donors].

BACKGROUND: Despite the established potentially curative role of allogeneic hematopoietic cell transplantation (alloHCT) in managing MF, the choice of alternative donors for patients lacking matched donors remains a challenge, and the optimal graft source in this disease entity continues to be an ongoing debate. OBJECTIVES: We aimed to evaluate the impact of donor type: umbilical cord blood transplant supported CD34+ haploidentical donor (haplo-cord) vs adult matched related donor (MRD) and matched unrelated donor (MUD) in 40 adult patients with primary or secondary MF, including those progressing to accelerated phase (AP) or blast phase (BP), who underwent their first allo-HCT. The primary objective of this study was to analyze the impact of stem cell source on primary endpoints of overall survival (OS), graft versus host disease (GVHD) and non-relapse mortality (NRM). RESULTS: Median follow-up for all alive patients was 53 months (range 0.3-63 months). Nine patients (22.5%) underwent an MRD allo-HCT, 15 patients (37.5%) underwent a MUD allo-HCT, and 16 patients (40%) underwent a haplo-cord allo-HCT. Four patients died without neutrophil engraftment: 3 (19%) in haplo-cord group and one (4%) in MRD/MUD group. The cumulative incidence of ANC engraftment by day 60 was 80% (95%CI 45-94) in the haplo-cord group and 92% (95%CI 65-98) in the MRD/MUD group (p=0.09). The cumulative incidence of platelet engraftment by day 60 was 59% (95%CI 27-81) in haplo-cord group and 75% (95%CI 51-88) in MRD/MUD group (p=0.4). OS was 62% at 1 year (95%CI 49-79) and 34% at 3 years (95%CI 21-55). The 3-yr OS was similar between the haplo-cord group and the MRD/MUD (37% vs 32%, p=0.9). The 1-yr OS for accelerated/blast phase AP/BP patients was 50% (95%CI 27-93) in the haplo-cord group, compared to 40% (95%CI 19-86) in the MRD/MUD. The 1-yr OS for chronic phase CP patients was 83% (95%CI 58-100) in the haplo-cord group, compared to 79% (95%CI 60-100) in the MRD/MUD group. The cumulative incidence of relapse at 3 years in the haplo-cord group was 13% (95%CI 1.8-34), and in the MRD/MUD group was 28% (95%CI 10-49) (p=0.36). 1-yr non-relapse mortality (NRM) was 38% (95%CI 15-61) in the haplo-cord group and 33% (95%CI 15-52) in the MRD/MUD group. 3-yr NRM was 48% (95%CI 19-72) in the haplo-cord group and 54% (95%CI 29-73) in MRD/MUD group(p=0.95). CONCLUSION: We showed no significant difference in OS, relapse, and NRM outcomes after haplo-cord transplant compared to adult matched donors' grafts (MRD or MUD) in MF patients. However, there were more graft failures in patients transplanted with a haplo-cord transplants and delayed engraftments with inadequate haplo myeloid bridges. Despite the small sample size in our study, considering our findings and the availability of other alternative donors, using haplo-cord platforms may no longer be justified for myelofibrosis unless the UCB engraftment dynamics can be optimized.

Treatment comparison of hydroxyurea versus ruxolitinib in essential thrombocythaemia: A matched-cohort analysis.

Hydroxyurea is the preferred first-line cytoreductive treatment for high-risk essential thrombocythaemia (ET), but many patients are intolerant or refractory to hydroxyurea. Ruxolitinib has been shown to improve symptoms in patients with ET. This post hoc analysis compared the clinical outcomes of patients with ET who received hydroxyurea only with those who switched from hydroxyurea to ruxolitinib due to intolerance/resistance to hydroxyurea. Patients with ET refractory/intolerant to hydroxyurea treated with ruxolitinib in a completed phase 2 study (HU-RUX) were propensity score matched with patients who received hydroxyurea only in an observational study (HU). Changes in leukocyte and platelet counts were reported at 6-month intervals during the 48-month follow-up. Following propensity score matching, 37 patients were included for analysis in each cohort. Mean (standard deviation [SD]) leukocyte and platelet counts at index were higher for HU-RUX versus HU (leukocyte: 9.3 [5.1] vs. 6.8 [3.1] × 109/L; platelet: 1027.4 [497.8] vs. 513.9 [154.7] × 109/L), both of which decreased significantly from index to 6 months through to 48 months in HU-RUX (mean [SD] change from index at 6 months-leukocyte: -1.8 [4.6] × 109/L; platelet: -391.7 [472.9] × 109/L; at 48 months-leukocyte: -3.8 [5.3] × 109/L; platelet: -539.0 [521.8] × 109/L), but remained relatively stable in HU (mean [SD] change from index at 6 months-leukocyte: 0 [1.8] × 109/L; platelet: -5.7 [175.3] × 109/L; at 48 months-leukocyte: -0.1 [2.7] × 109/L; platelet: -6.9 [105.1] × 109/L). In conclusion, these results demonstrate that switching from hydroxyurea to ruxolitinib in patients with ET who are intolerant or refractory to hydroxyurea could improve abnormal haematologic values similar to those who receive first-line hydroxyurea.

Rusfertide, a Hepcidin Mimetic, for Control of Erythrocytosis in Polycythemia Vera.

BACKGROUND: Polycythemia vera is a chronic myeloproliferative neoplasm characterized by erythrocytosis. Rusfertide, an injectable peptide mimetic of the master iron regulatory hormone hepcidin, restricts the availability of iron for erythropoiesis. The safety and efficacy of rusfertide in patients with phlebotomy-dependent polycythemia vera are unknown. METHODS: In part 1 of the international, phase 2 REVIVE trial, we enrolled patients in a 28-week dose-finding assessment of rusfertide. Part 2 was a double-blind, randomized withdrawal period in which we assigned patients, in a 1:1 ratio, to receive rusfertide or placebo for 12 weeks. The primary efficacy end point was a response, defined by hematocrit control, absence of phlebotomy, and completion of the trial regimen during part 2. Patient-reported outcomes were assessed by means of the modified Myeloproliferative Neoplasm Symptom Assessment Form (MPN-SAF) patient diary (scores range from 0 to 10, with higher scores indicating greater severity of symptoms). RESULTS: Seventy patients were enrolled in part 1 of the trial, and 59 were assigned to receive rusfertide (30 patients) or placebo (29 patients) in part 2. The estimated mean (±SD) number of phlebotomies per year was 8.7±2.9 during the 28 weeks before the first dose of rusfertide and 0.6±1.0 during part 1 (estimated difference, 8.1 phlebotomies per year). The mean maximum hematocrit was 44.5±2.2% during part 1 as compared with 50.0±5.8% during the 28 weeks before the first dose of rusfertide. During part 2, a response was observed in 60% of the patients who received rusfertide as compared with 17% of those who received placebo (P = 0.002). Between baseline and the end of part 1, rusfertide treatment was associated with a decrease in individual symptom scores on the MPN-SAF in patients with moderate or severe symptoms at baseline. During parts 1 and 2, grade 3 adverse events occurred in 13% of the patients, and none of the patients had a grade 4 or 5 event. Injection-site reactions of grade 1 or 2 in severity were common. CONCLUSIONS: In patients with polycythemia vera, rusfertide treatment was associated with a mean hematocrit of less than 45% during the 28-week dose-finding period, and the percentage of patients with a response during the 12-week randomized withdrawal period was greater with rusfertide than with placebo. (Funded by Protagonist Therapeutics; REVIVE ClinicalTrials.gov number, NCT04057040.).

Patient-reported outcomes from the phase 3 ADMIRAL trial in patients with FLT3-mutated relapsed/refractory AML.

Patient-reported outcomes (PROs) can inform treatment selection and assess treatment value in acute myeloid leukemia (AML). We evaluated PROs from the ADMIRAL trial (NCT02421939) in patients with FLT3-mutated relapsed/refractory (R/R) AML. PRO instruments consisted of Brief Fatigue Inventory (BFI), Functional Assessment of Cancer Therapy-Leukemia (FACT-Leu), Functional Assessment of Chronic Illness Therapy-Dyspnea Short Form (FACIT-Dys SF), EuroQoL 5-Dimension 5-Level (EQ-5D-5L), and leukemia treatment-specific symptom questionnaires. Clinically significant effects on fatigue were observed with gilteritinib during the first two treatment cycles. Shorter survival was associated with clinically significant worsening of BFI, FACT-Leu, FACIT-Dys SF, and EQ-5D-5L measures. Transplantation and transfusion independence in gilteritinib-arm patients were also associated with maintenance or improvement in PROs. Health-related quality of life remained stable in the gilteritinib arm. Hospitalization had a small but significant effect on patient-reported fatigue. Gilteritinib was associated with a favorable effect on fatigue and other PROs in patients with FLT3-mutated R/R AML.

Immunogenicity of COVID-19 mRNA vaccines in patients with acute myeloid leukemia and myelodysplastic syndrome.

Immunocompromised patients are susceptible to complications from severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). The mRNA vaccines BNT162b2 and mRNA-1273 are effective in immunocompetent adults, but have diminished activity in immunocompromised patients. We measured anti-spike SARS-CoV-2 antibody (anti-S) response, avidity, and surrogate neutralizing antibody activity in COVID-19 vaccinated patients with acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS). Anti-S was induced in 89% of AML and 88% of MDS patients, but median levels were significantly lower than in healthy controls. SARS-CoV-2 antibody avidity and neutralizing activity from AML patients were significantly lower than controls. Antibody avidity was significantly greater in patients after mRNA-1273 versus BNT162b2; there were trends toward higher anti-S levels and greater neutralizing antibody activity after mRNA-1273 vaccination. Patients with AML and MDS are likely to respond to COVID-19 mRNA vaccination, but differences in anti-S levels, avidity, and neutralizing antibody activity may affect clinical outcomes and require further study.

A phase Ib dose escalation study of oral monotherapy with KX2-391 in elderly patients with acute myeloid leukemia.

Poor tolerance to standard therapies and multi-drug resistance complicate treatment of elderly patients with acute myeloid leukemia (AML). It is therefore imperative to explore novel tolerable agents and target alternative pathways. KX2-391 is an oral non-ATP-competitive inhibitor of Src kinase and tubulin polymerization. This multi-center phase Ib open-label safety and activity study involved elderly patients with relapsed or refractory AML, or who declined standard chemotherapy. Twenty-four patients averaging 74 years of age were enrolled. The majority previously received hypomethylating agents. Five doses were tested: 40 mg (n = 1), 80 mg (n = 2), 120 mg (n = 8), 140 mg (n = 12), and 160 mg (n = 1). Seven patients were treated for 12 days or less, nine for 15-29 days, five for 33-58 days, and three for 77-165 days. One patient receiving 120 mg for 165 days had reduced splenomegaly and survived 373 days. Another had no evidence of disease progression for 154 days. One patient receiving 160 mg for 12 days remained treatment-free for about 18 months. Dose-limiting toxicities occurred in eight patients at: 120 mg (transaminitis, hyperbilirubinemia), 140 mg (mucositis, allergic reaction, transaminitis, acute kidney injury), and 160 mg (mucositis). The maximum tolerated dose for KX2-391 was 120 mg once daily. KX2-391 bone marrow concentrations were approximately similar to plasma concentrations. This is the first study to evaluate the safety of KX2-391 in elderly patients with AML. Further studies are warranted, including alternative dosing phase I trials evaluating shorter courses at higher doses and phase II trials. (Clinical Trial Registration:The study was registered at ClinicalTrials.gov: NCT01397799 (July 20, 2011)).

Geriatric assessment for older adults receiving less-intensive therapy for acute myeloid leukemia: report of CALGB 361101.

Geriatric assessment (GA) predicts survival among older adults with acute myeloid leukemia (AML) treated intensively. We evaluated the predictive utility of GA among older adults treated with low-intensity therapy on a multisite trial. We conducted a companion study (CALGB 361101) to a randomized phase 2 trial (CALGB 11002) of adults ≥60 years and considered "unfit" for intensive therapy, testing the efficacy of adding bortezomib to decitabine therapy. On 361101, GA and quality of life (QOL) assessment was administered prior to treatment and every other subsequent cycle. Relationships between baseline GA and QOL measures with survival were evaluated using Kaplan-Meier estimation and Cox proportional hazards models. One-hundred sixty-five patients enrolled in CALGB 11002, and 96 (52%) of them also enrolled in 361101 (median age, 73.9 years). Among participants, 85.4% completed ≥1 baseline assessment. In multivariate analyses, greater comorbidity (hematopoietic cell transplantation-specific comorbidity index >3), worse cognition (Blessed Orientation-Memory-Concentration score >4), and lower European Organization for Research and Treatment of Cancer global QOL scores at baseline were significantly associated with shorter overall survival (P < .05 each) after adjustment for Karnofsky Performance Status, age, and treatment arm. Dependence in instrumental activities of daily living and cognitive impairment were associated with 6-month mortality (hazard ratio [HR], 3.5; confidence interval [CI], 1.2-10.4; and HR, 3.1; CI, 1.1-8.6, respectively). GA measures evaluating comorbidity, cognition, and self-reported function were associated with survival and represent candidate measures for screening older adults planned to receive lower-intensity AML therapies. This trial was registered at www.clinicaltrials.gov as #NCT01420926 (CALGB 11002).

Addition of Navitoclax to Ongoing Ruxolitinib Therapy for Patients With Myelofibrosis With Progression or Suboptimal Response: Phase II Safety and Efficacy.

PURPOSE: Targeting the BCL-XL pathway has demonstrated the ability to overcome Janus kinase inhibitor resistance in preclinical models. This phase II trial investigated the efficacy and safety of adding BCL-XL/BCL-2 inhibitor navitoclax to ruxolitinib therapy in patients with myelofibrosis with progression or suboptimal response to ruxolitinib monotherapy (ClinicalTrials.gov identifier: NCT03222609). METHODS: Thirty-four adult patients with intermediate-/high-risk myelofibrosis who had progression or suboptimal response on stable ruxolitinib dose (≥ 10 mg twice daily) were administered navitoclax at 50 mg once daily starting dose, followed by escalation to a maximum of 300 mg once daily in once in weekly increments (if platelets were ≥ 75 × 109/L). The primary end point was ≥ 35% spleen volume reduction (SVR35) from baseline at week 24. Secondary end points included ≥ 50% reduction in total symptom score (TSS50) from baseline at week 24, hemoglobin improvement, change in bone marrow fibrosis (BMF) grade, and safety. RESULTS: High molecular risk mutations were identified in 58% of patients, and 52% harbored ≥ 3 mutations. SVR35 was achieved by 26.5% of patients at week 24, and by 41%, at any time on study, with an estimated median duration of SVR35 of 13.8 months. TSS50 was achieved by 30% (6 of 20) of patients at week 24, and BMF improved by 1-2 grades in 33% (11 of 33) of evaluable patients. Anemia response was achieved by 64% (7 of 11), including one patient with baseline transfusion dependence. Median overall survival was not reached with a median follow-up of 21.6 months. The most common adverse event was reversible thrombocytopenia without clinically significant bleeding (88%). CONCLUSION: The addition of navitoclax to ruxolitinib in patients with persistent or progressive myelofibrosis resulted in durable SVR35, improved TSS, hemoglobin response, and BMF. Further investigation is underway to qualify the potential for disease modification.

Comparison of Multiple Clinical Testing Modalities for Assessment of NPM1-Mutant AML.

BACKGROUND: NPM1 mutation status can influence prognosis and management in AML. Accordingly, clinical testing (i.e., RT-PCR, NGS and IHC) for mutant NPM1 is increasing in order to detect residual disease in AML, alongside flow cytometry (FC). However, the relationship of the results from RT-PCR to traditional NGS, IHC and FC is not widely known among many practitioners. Herein, we aim to: i) describe the performance of RT-PCR compared to traditional NGS and IHC for the detection of mutant NPM1 in clinical practice, and also compare it to FC, and ii) provide our observations regarding the advantages and disadvantages of each approach in order to inform future clinical testing algorithms. METHODS: Peripheral blood and bone marrow samples collected for clinical testing at variable time points during patient management were tested by quantitative, real-time, RT-PCR and results were compared to findings from a Myeloid NGS panel, mutant NPM1 IHC and FC. RESULTS: RT-PCR showed superior sensitivity compared to NGS, IHC and FC with the main challenge of NGS, IHC and FC being the ability to identify a low disease burden (<0.5% NCN by RT-PCR). Nevertheless, the positive predictive value of NGS, IHC and FC were each ≥ 80% indicating that positive results by those assays are typically associated with RT-PCR positivity. IHC, unlike bulk methods (RT-PCR, NGS and FC), is able provide information regarding cellular/architectural context of disease in biopsies. FC did not identify any NPM1-mutated residual disease not already detected by RT-PCR, NGS or IHC. CONCLUSION: Overall, our findings demonstrate that RT-PCR shows superior sensitivity compared to a traditional Myeloid NGS, suggesting the need for "deep-sequencing" NGS panels for NGS-based monitoring of residual disease in NPM1-mutant AML. IHC provides complementary cytomorphologic information to RT-PCR. Lastly, FC may not be necessary in the setting of post-therapy follow up for NPM1-mutated AML. Together, these findings can help inform future clinical testing algorithms.

CPX-351 versus 7+3 cytarabine and daunorubicin chemotherapy in older adults with newly diagnosed high-risk or secondary acute myeloid leukaemia: 5-year results of a randomised, open-label, multicentre, phase 3 trial.

BACKGROUND: Daunorubicin and cytarabine are used as standard induction chemotherapy for patients with acute myeloid leukaemia. CPX-351 is a dual-drug liposomal encapsulation of daunorubicin and cytarabine in a synergistic 1:5 molar ratio. Primary analysis of the phase 3 trial in adults aged 60-75 years with newly diagnosed high-risk or secondary acute myeloid leukaemia provided support for approval of CPX-351 by the US Food and Drug Administration and European Medicines Agency. We describe the prospectively planned final 5-year follow-up results. METHODS: This randomised, open-label, multicentre, phase 3 trial was done across 39 academic and regional cancer centres in the USA and Canada. Eligible patients were aged 60-75 years and had a pathological diagnosis of acute myeloid leukaemia according to WHO 2008 criteria, no previous induction therapy for acute myeloid leukaemia, and an Eastern Cooperative Oncology Group performance status of 0-2. Patients were randomly assigned 1:1 (stratified by age and acute myeloid leukaemia subtype) to receive up to two induction cycles of CPX-351 (100 units/m2 administered as a 90-min intravenous infusion on days 1, 3, and 5; on days 1 and 3 for the second induction) or standard chemotherapy (cytarabine 100 mg/m2 per day continuous intravenous infusion for 7 days plus intravenous daunorubicin 60 mg/m2 on days 1, 2, and 3 [7+3]; cytarabine for 5 days and daunorubicin on days 1 and 2 for the second induction [5+2]). Patients with complete remission or complete remission with incomplete neutrophil or platelet recovery could receive up to tw cycles of consolidation therapy with CPX-351 (65 units/m2 90-min infusion on days 1 and 3) or chemotherapy (5+2, same dosage as in the second induction cycle). The primary outcome was overall survival analysed in all randomly assigned patients. No additional adverse events were collected with long-term follow-up, except data for deaths. This trial is registered with ClinicalTrials.gov, NCT01696084, and is complete. FINDINGS: Between Dec 20, 2012, and Nov 11, 2014, 309 patients with newly diagnosed high-risk or secondary acute myeloid leukaemia were enrolled and randomly assigned to receive CPX-351 (153 patients) or 7+3 (156 patients). At a median follow-up of 60·91 months (IQR 60·06-62·98) in the CPX-351 group and 59·93 months (59·73-60·50) in the 7+3 group, median overall survival was 9·33 months (95% CI 6·37-11·86) with CPX-351 and 5·95 months (4·99-7·75) with 7+3 (HR 0·70, 95% CI 0·55-0·91). 5-year overall survival was 18% (95% CI 12-25%) in the CPX-351 group and 8% (4-13%) in the 7+3 group. The most common cause of death in both groups was progressive leukaemia (70 [56%] of 124 deaths in the CPX-351 group and 74 [53%] of 140 deaths in the 7+3 group). Six (5%) of 124 deaths in the CPX-351 group and seven (5%) of 140 deaths in the 7+3 group were considered related to study treatment. INTERPRETATION: After 5 years of follow-up, the improved overall survival with CPX-351 versus 7+3 was maintained, which supports the previous evidence that CPX-351 can contribute to long-term remission and improved overall survival in patients aged 60-75 years with newly diagnosed high-risk or secondary acute myeloid leukaemia. FUNDING: Jazz Pharmaceuticals.

Interferon-alpha for treating polycythemia vera yields improved myelofibrosis-free and overall survival.

Interferon-alpha (rIFNα) is the only disease-modifying treatment for polycythemia vera (PV), but whether or not it prolongs survival is unknown. This large single center retrospective study of 470 PV patients compares the myelofibrosis-free survival (MFS) and overall survival (OS) with rIFNα to two other primary treatments, hydroxyurea (HU) and phlebotomy-only (PHL-O). The median age at diagnosis was 54 years (range 20-94) and the median follow-up was 10 years (range 0-45). Two hundred and twenty-nine patients were women (49%) and 208 were high-risk (44%). The primary treatment was rIFNα in 93 (20%), HU in 189 (40%), PHL-O in 133 (28%) and other cytoreductive drugs in 55 (12%). The treatment groups differed by ELN risk score (p < 0.001). In low-risk patients, 20-year MFS for rIFNα, HU, and PHL-O was 84%, 65% and 55% respectively (p < 0.001) and 20-year OS was 100%, 85% and 80% respectively (p = 0.44). In high-risk patients, 20-year MFS for rIFNα, HU, and PHL-O was 89%, 41% and 36% respectively (p = 0.19) and 20-year OS was 66%, 40%, 14% respectively (p = 0.016). In multivariable analysis, longer time on rIFNα was associated with a lower risk of myelofibrosis (HR: 0.91, p < 0.001) and lower mortality (HR: 0.94, p = 0.012). In conclusion, this study supports treatment of PV with rIFNα to prevent myelofibrosis and potentially prolong survival.

A dose escalation study of RO6870810/TEN-10 in patients with acute myeloid leukemia and myelodysplastic syndrome.

Bromodomain and extra-terminal (BET) proteins can drive carcinogenesis and therapy resistance. RO6870810 (RO) is a novel, small-molecule BET inhibitor. We conducted a study in 32 patients with relapsed/refractory acute myeloid leukemia and hypomethylating agent-refractory myelodysplastic syndrome (NCT02308761). Pharmacodynamic assessments showed decreases in CD11b in peripheral blood mononuclear cells at RO concentrations above 120 ng/mL. Treatment emergent adverse events were generally mild and the most frequent were fatigue, injection site reactions, diarrhea, decreased appetite and nausea. There were no treatment-related deaths. Potential drug-related dose limiting toxicities included decreased appetite, congestive cardiac failure, hypertension, fatigue, increased conjugated bilirubin and increased gamma glutamyltransferase. One AML patient achieved complete remission after withdrawal from study. Eleven AML patients experienced SD. For AML, the median OS was 72.0 days. For MDS, two patients experienced SD. Further development of RO as monotherapy was discontinued due to lack of efficacy, but combinations with other agents are under consideration.

Long-term follow-up of blinatumomab in patients with relapsed/refractory Philadelphia chromosome-positive B-cell precursor acute lymphoblastic leukaemia: Final analysis of ALCANTARA study.

AIM: To evaluate long-term durability of blinatumomab, a BiTE® (bispecific T-cell engager) molecule, in adults with relapsed/refractory (R/R) Philadelphia chromosome-positive (Ph+) B-cell precursor acute lymphoblastic leukaemia (ALL). METHODS: In this final analysis of an open-label, single-arm, phase 2, multicentre ALCANTARA study (NCT02000427), adults (age ≥18 years) with Ph+ ALL who had relapsed or were refractory to at least one TKI were included. The primary endpoint was the proportion of patients who achieved complete remission (CR)/CR with partial haematologic recovery (CRh) during the first two cycles of blinatumomab treatment. RESULTS: The final analysis included 45 patients who completed the study between 3rd January 2014 and 6th January 2017, of which 16 (35.6%; 95% CI, 21.9%-51.2%) achieved CR/CRh within the first two blinatumomab cycles. After a median follow-up of 16.1 months, median relapse-free survival (RFS) was 6.8 (95% CI, 4.4-not estimable [NE]) months. Median overall survival (OS) was 9.0 (95% CI, 5.7-13.5) months with a median follow-up of 25.1 months. Median OS in patients with CR (19.8 [95% CI, 12.1-NE] months) was greater than in those without CR (6.0 [95% CI, 2.9-7.1] months). Of 16 patients with CR/CRh, 14 achieved complete minimal residual disease (MRD) response; the median duration of complete MRD response was 9.7 (95% CI, 5.2-NE) months. Treatment-related adverse events were consistent with those previously reported. CONCLUSION: Long-term durability of responses to blinatumomab was demonstrated in patients with R/R Ph+ ALL.

Assessment of Outcomes After Stopping Tyrosine Kinase Inhibitors Among Patients With Chronic Myeloid Leukemia: A Nonrandomized Clinical Trial.

IMPORTANCE: Tyrosine kinase inhibitors (TKIs) have been associated with improved survival of patients with chronic myeloid leukemia (CML) but are also associated with adverse effects, especially fatigue and diarrhea. Discontinuation of TKIs is safe and is associated with the successful achievement of treatment-free remission (TFR) for some patients. OBJECTIVE: To evaluate molecular recurrence (MRec) and patient-reported outcomes (PROs) after TKI discontinuation for US patients with CML. DESIGN, SETTING, AND PARTICIPANTS: The Life After Stopping TKIs (LAST) study was a prospective single-group nonrandomized clinical trial that enrolled 172 patients from 14 US academic medical centers from December 18, 2014, to December 12, 2016, with a minimum follow-up of 3 years. Participants were adults with chronic-phase CML whose disease was well controlled with imatinib, dasatinib, nilotinib, or bosutinib. Statistical analysis was performed from August 13, 2019, to March 23, 2020. INTERVENTION: Discontinuation of TKIs. MAIN OUTCOMES AND MEASURES: Molecular recurrence, defined as loss of major molecular response (BCR-ABL1 International Scale ratio >0.1%) by central laboratory testing, and PROs (Patient-Reported Outcomes Measurement Information System computerized adaptive tests) were monitored. Droplet digital polymerase chain reaction (ddPCR) was performed on samples with undetectable BCR-ABL1 by standard real-time quantitative polymerase chain reaction (RQ-PCR). RESULTS: Of 172 patients, 89 were women (51.7%), and the median age was 60 years (range, 21-86 years). Of 171 patients evaluable for molecular analysis, 112 (65.5%) stayed in major molecular response, and 104 (60.8%) achieved TFR. Undetectable BCR-ABL1 by either ddPCR or RQ-PCR at the time of TKI discontinuation (hazard ratio, 3.60; 95% CI, 1.99-6.50; P < .001) and at 3 months (hazard ratio, 5.86; 95% CI, 3.07-11.1; P < .001) was independently associated with MRec. Molecular recurrence for patients with detectable BCR-ABL1 by RQ-PCR was 50.0% (14 of 28), undetectable BCR-ABL1 by RQ-PCR but detectable by ddPCR was 64.3% (36 of 56), and undetectable BCR-ABL1 by both ddPCR and RQ-PCR was 10.3% (9 of 87) (P ≤ .001). Of the 112 patients in TFR at 12 months, 90 (80.4%) had a clinically meaningful improvement in fatigue, 39 (34.8%) had a clinically meaningful improvement in depression, 98 (87.5%) had a clinically meaningful improvement in diarrhea, 24 (21.4%) had a clinically meaningful improvement in sleep disturbance, and 5 (4.5%) had a clinically meaningful improvement in pain interference. Restarting a TKI resulted in worsening of PROs. CONCLUSIONS AND RELEVANCE: In this study, TKI discontinuation was safe, and 60.8% of patients remained in TFR. Discontinuation of TKIs was associated with improvements in PROs. These findings should assist patients and physicians in their decision-making regarding discontinuation of TKIs. Detectable BCR-ABL1 by RQ-PCR or ddPCR at the time of TKI discontinuation was associated with higher risk of MRec; clinical application of this finding should be confirmed in other studies. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02269267.

Pediatric-inspired chemotherapy incorporating pegaspargase is safe and results in high rates of minimal residual disease negativity in adults up to age 60 with Philadelphia chromosome-negative acute lymphoblastic leukemia.

Administration of pediatric-inspired chemotherapy to adults up to age 60 with acute lymphoblastic leukemia (ALL) is challenging in part due to toxicities of asparaginase as well as myelosuppression. We conducted a multicenter phase II clinical trial (NCT01920737) investigating a pediatric-inspired regimen, based on the augmented arm of the Children's Cancer Group 1882 protocol, incorporating 6 doses of pegaspargase 2000 IU/m2, rationally synchronized to avoid overlapping toxicity with other agents. We treated 39 adults ages 20-60 years (median, 38 years) with newly-diagnosed ALL (n=31) or lymphoblastic lymphoma (n=8). Grade 3-4 hyperbilirubinemia occurred frequently and at higher rates in patients 40-60 (n=18) vs 18-39 (n=21) years (44 vs 10%, p=0.025). However, 8/9 patients re-challenged with pegaspargase did not experience recurrent grade 3-4 hyperbilirubinemia. Grade 3-4 hypertriglyceridemia and hypofibrinogenemia were common (each 59%). Asparaginase activity at 7-days post-infusion reflected levels associated with adequate asparagine depletion, even among those with antibodies to pegaspargase. Complete response (CR)/CR with incomplete hematologic recovery was observed post-induction in 38/39 (97%) patients. Among patients with ALL, rates of MRD negativity by multiparameter flow cytometry were 33% and 83% following Induction Phase I and Phase II, respectively. Event-free and overall survival at 3 years (67.8 and 76.4%) compare favorably to outcomes observed in other series. These results demonstrate pegaspargase can be administered in the context of intensive multi-agent chemotherapy to adults age ≤60 with manageable toxicity. This regimen may serve as an effective backbone into which novel agents may be incorporated in future frontline studies.

Adoptive immunotherapy with CB following chemotherapy for patients with refractory myeloid malignancy: chimerism and response.

We conducted a prospective evaluation of cord blood (CB)-derived adoptive cell therapy, after salvage chemotherapy, for patients with advanced myeloid malignancies and poor prognosis. Previously, we reported safety, feasibility, and preliminary efficacy of this approach. We present updated results in 31 patients who received intensive chemotherapy followed by CB infusion and identify predictors of response. To enhance the antileukemic effect, we selected CB units (CBU) with shared inherited paternal antigens and/or noninherited maternal antigens with the recipients. Twenty-eight patients with acute myeloid leukemia (AML), 2 with myelodysplastic syndrome, and 1 in chronic myeloid leukemia myeloid blast crisis were enrolled; 9 had relapsed after allogeneic transplant. Response was defined as <5% blasts in hypocellular bone marrow at 2 weeks after treatment. Thirteen patients (42%) responded; a rate higher than historical data with chemotherapy only. Twelve had CBU-derived chimerism detected; chimerism was a powerful predictor of response (P < .001). CBU lymphocyte content and a prior transplant were associated with chimerism (P < .01). Safety was acceptable: 3 patients developed mild cytokine release syndrome, 2 had grade 1 and 2 had grade 4 graft-versus-host disease. Seven responders and 6 nonresponders (after additional therapy) received subsequent transplant; 5 are alive (follow-up, 5-47 months). The most common cause of death for nonresponders was disease progression, whereas for responders it was infection. CB-derived adoptive cell therapy is feasible and efficacious for refractory AML. Banked CBU are readily available for treatment. Response depends on chimerism, highlighting the graft-versus-leukemia effect of CB cell therapy. This trial was registered at www.clinicaltrials.gov as #NCT02508324.

Management of hyperleukocytosis and impact of leukapheresis among patients with acute myeloid leukemia (AML) on short- and long-term clinical outcomes: a large, retrospective, multicenter, international study.

Hyperleukocytosis in acute myeloid leukemia (AML) is associated with inferior outcomes. There is limited high quality evidence to support the benefits of leukapheresis. We retrospectively collected data from patients with newly-diagnosed AML who presented with a white cell count (WBC) >50 × 109/L to 12 centers in the United States and Europe from 2006 to 2017 and received intensive chemotherapy. Logistic regression models estimated odds ratios for 30-day mortality and achievement of composite complete remission (CRc). Cox proportional hazard models estimated hazard ratios for overall survival (OS). Among 779 patients, clinical leukostasis was reported in 27%, and leukapheresis was used in 113 patients (15%). Thirty-day mortality was 16.7% (95% CI: 13.9-19.3%). Median OS was 12.6 months (95% CI: 11.5-14.9) among all patients, and 4.5 months (95% CI: 2.7-7.1) among those ≥65 years. Use of leukapheresis did not significantly impact 30-day mortality, achievement of CRc, or OS in multivariate analysis based on available data or in analysis based on multiple imputation. Among patients with investigator-adjudicated clinical leukostasis, there were statistically significant improvements in 30-day mortality and OS with leukapheresis in unadjusted analysis, but not in multivariate analysis. Given the significant resource use, cost, and potential complications of leukapheresis, randomized studies are needed to evaluate its value.