CPX-351 Pharmacokinetics and Safety in Adults with Hematologic Malignancies and Renal Function Impairment: Phase 1 Trial.

This open-label phase 1 study (clinicaltrials.gov, NCT03555955) assessed CPX-351 pharmacokinetics (PK) and safety in patients with hematologic malignancies with normal or impaired renal function. Patients were enrolled into three cohorts based on their creatinine clearance (CrCl): ≥90 mL/min (Cohort 1, normal renal function, n = 7), 30 to <59 mL/min (Cohort 2, moderate renal impairment, n = 8), or <30 mL/min (Cohort 3, severe renal impairment, n = 6). Patients received intravenous CPX-351 for initial induction; blood and urine samples were collected for PK analysis. The primary objective was to assess the PK parameters for cytarabine, daunorubicin, and their respective metabolites, arabinosyluracil (Ara-U) and daunorubicinol. Renal impairment did not significantly impact the cytarabine, daunorubicin, or daunorubicinol exposure, but it caused a slight increase in the Ara-U exposure. The CPX-351 side effect profile was similar in patients with impaired renal function compared to those with normal renal function. All the patients reported ≥1 treatment-emergent adverse event (TEAE), most commonly febrile neutropenia and nausea (57% each) and hyperglycemia (43%); no patients discontinued treatment due to TEAEs. These data suggest that CPX-351 dose adjustment is not required for patients with hematologic malignancies with moderate or severe renal impairment.

Efficacy and safety of CPX-351 versus 7 + 3 chemotherapy by European LeukemiaNet 2017 risk subgroups in older adults with newly diagnosed, high-risk/secondary AML: post hoc analysis of a randomized, phase 3 trial.

CPX-351 (Europe: Vyxeos® liposomal; United States: Vyxeos®) is a dual-drug liposomal encapsulation of daunorubicin and cytarabine in a synergistic 1:5 molar ratio. In a phase 3 study in older adults with newly diagnosed, high-risk/secondary AML, CPX-351 improved the remission frequency, overall survival, and post-transplant survival versus 7 + 3. This post hoc analysis evaluated the final 5-year follow-up outcomes according to the European LeukemiaNet 2017 risk classification. CPX-351-treated patients had a higher remission frequency (adverse risk: 41% vs 26%; intermediate risk: 58% vs 39%) and longer median overall survival (adverse risk: 7.59 vs 5.52 months; intermediate risk: 11.86 vs 7.75 months) and post-transplant survival (adverse risk: 43.14 vs 7.08 months; intermediate risk: not reached vs 13.57 months) versus 7 + 3, with outcomes generally poorer among patients with adverse-risk AML. The safety profile of CPX-351 among patients with adverse-risk or intermediate-risk AML was consistent with that of the overall study population. Early mortality was lower, and hospitalization length of stay per patient-year was shorter with CPX-351 versus 7 + 3 within the adverse-risk and intermediate-risk subgroups. The favorable outcomes observed with CPX-351 in this post hoc analysis are consistent with results for the overall study population and further support the use of CPX-351 in these patients.ClinicalTrials.gov Identifier: NCT01696084.

Quality-adjusted Time Without Symptoms of disease or Toxicity (Q-TWiST) analysis of CPX-351 versus 7 + 3 in older adults with newly diagnosed high-risk/secondary AML.

BACKGROUND: CPX-351 (United States: Vyxeos®; Europe: Vyxeos® Liposomal), a dual-drug liposomal encapsulation of daunorubicin and cytarabine in a synergistic 1:5 molar ratio, is approved by the US FDA and the EMA for the treatment of adults with newly diagnosed therapy-related acute myeloid leukemia or acute myeloid leukemia with myelodysplasia-related changes. In a pivotal phase 3 study that evaluated 309 patients aged 60 to 75 years with newly diagnosed high-risk/secondary acute myeloid leukemia, CPX-351 significantly improved median overall survival versus conventional 7 + 3 chemotherapy (cytarabine continuous infusion for 7 days plus daunorubicin for 3 days), with a comparable safety profile. A Quality-adjusted Time Without Symptoms of disease or Toxicity (Q-TWiST) analysis of the phase 3 study was performed to compare survival quality between patients receiving CPX-351 versus conventional 7 + 3 after 5 years of follow-up. METHODS: Patients were randomized 1:1 between December 20, 2012 and November 11, 2014 to receive induction with CPX-351 or 7 + 3. Survival time for each patient was partitioned into 3 health states: TOX (time with any grade 3 or 4 toxicity or prior to remission), TWiST (time in remission without relapse or grade 3 or 4 toxicity), and REL (time after relapse). Within each treatment arm, Q-TWiST was calculated by adding the mean time spent in each health state weighted by its respective quality-of-life, represented by health utility. The relative Q-TWiST gain, calculated as the difference in Q-TWiST between treatment arms divided by the mean survival of the 7 + 3 control arm, was determined in order to evaluate results in the context of other Q-TWiST analyses. RESULTS: The relative Q-TWiST gain with CPX-351 versus 7 + 3 was 53.6% in the base case scenario and 39.8% among responding patients. Across various sensitivity analyses, the relative Q-TWiST gains for CPX-351 ranged from 48.0 to 57.6%, remaining well above the standard clinically important difference threshold of 15% for oncology. CONCLUSIONS: This post hoc analysis demonstrates that CPX-351 improved quality-adjusted survival, further supporting the clinical benefit in patients with newly diagnosed high-risk/secondary acute myeloid leukemia. Trial registration This trial was registered on September 28, 2012 at www.clinicaltrials.gov as NCT01696084 ( https://clinicaltrials.gov/ct2/show/NCT01696084 ) and is complete.

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.

Older adults with newly diagnosed high-risk/secondary AML who achieved remission with CPX-351: phase 3 post hoc analyses.

CPX-351, a dual-drug liposomal encapsulation of daunorubicin/cytarabine in a synergistic 1:5 molar ratio, is approved for the treatment of adults with newly diagnosed, therapy-related acute myeloid leukemia (t-AML) or AML with myelodysplasia-related changes (AML-MRC). In a pivotal phase 3 study, patients aged 60 to 75 years with newly diagnosed, high-risk/secondary AML were randomized to receive CPX-351 or conventional 7+3 chemotherapy. In the primary endpoint analysis, CPX-351 demonstrated significantly prolonged median overall survival (OS) vs 7+3. These exploratory post hoc subgroup analyses evaluated the impact of achieving complete remission (CR) or CR with incomplete neutrophil or platelet recovery (CRi) with CPX-351 (73/153 [48%]) vs conventional 7+3 (52/56 [33%]) on outcomes. CPX-351 improved median OS vs 7+3 in patients who achieved CR or CRi (25.43 vs 10.41 months; hazard ratio = 0.49; 95% confidence interval, 0.31, 0.77). Improved median OS was seen across AML subtypes (t-AML, AML-MRC), age subgroups (60 to 69 vs 70 to 75 years), patients with prior hypomethylating agent exposure, and patients who did not undergo transplantation. Patients who achieved CR or CRi with CPX-351 also had a higher rate of transplantation, a longer median OS landmarked from the date of transplantation (not reached vs 11.65 months; hazard ratio = 0.43; 95% confidence interval, 0.21, 0.89), and a safety profile that was consistent with the known safety profile of 7+3. These results suggest deeper remissions may be achieved with CPX-351, leading to improved OS. This study was registered at www.clinicaltrials.gov as #NCT01696084.

Phase 1 study of CWP232291 in patients with relapsed or refractory acute myeloid leukemia and myelodysplastic syndrome.

CWP232291 (CWP291) is a small-molecule inhibitor of Wnt signaling that causes degradation of ß-catenin via apoptosis induction through endoplasmic reticulum stress activation. This first-in-human, open-label, dose-escalation study to evaluate the safety, maximum tolerated dose (MTD), and preliminary efficacy of CWP291 enrolled 69 patients with hematologic malignancies (acute myeloid leukemia [AML], n = 64; myelodysplastic syndrome, n = 5) in 15 dose-escalation cohorts of 4 to 334 mg/m2 using a modified 3+3 design and 1 dose-expansion cohort. CWP291 was administered IV daily for 7 days every 21 days. The most common treatment-emergent adverse events (TEAEs) were nausea (n = 44, 64%), vomiting (n = 32, 46%), diarrhea (n = 25, 36%), and infusion-related reactions (n = 20, 29%). Grade ≥3 TEAEs in >3 patients (5%) were pneumonia (n = 8, 12%); hypophosphatemia (n = 6, 8%); leukocytosis, nausea, cellulitis, sepsis, and hypokalemia (n = 5 each, 7% each); and hypertension (n = 4, 6%). Dose-limiting toxicities included nausea (n = 3) and abdominal pain, anaphylactic reaction, myalgia, and rash (n = 1, each); the MTD was defined at 257 mg/m2. CWP232204, the active metabolite of CWP291, showed pharmacokinetic linearity on both days 1 and 7, and a terminal half-life of ∼12 hours. Among 54 response-evaluable AML patients, there was one complete response at a dose of 153 mg/m2 and one partial response at 198 mg/m2; bone marrow blast percentage reduced from a median of 58.3% to 3.5% and 15.0% to 4.2%, respectively. Future studies will explore CWP291, with a mechanism of action aimed at eradication of earlier progenitors via Wnt pathway blockade, as combination therapy. This trial was registered at www.clinicaltrials.gov as #NCT01398462.

An oral fixed-dose combination of decitabine and cedazuridine in myelodysplastic syndromes: a multicentre, open-label, dose-escalation, phase 1 study.

BACKGROUND: Decitabine, a DNA methyltransferase 1 inhibitor or DNA hypomethylating compound, is not readily orally bioavailable because of rapid clearance by cytidine deaminase (CDA) in the gut and liver. This dose-escalation study, guided by pharmacokinetic and pharmacodynamic observations, evaluated whether simultaneous oral administration with the novel CDA inhibitor cedazuridine increases decitabine bioavailability for the treatment of myelodysplastic syndromes. METHODS: In this phase 1 study, we enrolled patients aged 18 years or older with myelodysplastic syndromes or chronic myelomonocytic leukaemia. Eligible patients were assigned to cohorts to receive escalating oral doses of decitabine and cedazuridine. The starting dose was decitabine 20 mg and cedazuridine 40 mg. Treatment cycles lasted 28 days, with 5 days of drug administration. In cycle 1, each patient received a cohort-defined dose of oral decitabine on day -3, a 1-h intravenous infusion of decitabine 20 mg/m2 on day 1, and cohort-defined doses of oral decitabine plus cedazuridine on days 2-5. In cycles 2 and beyond, the oral decitabine and cedazuridine were given on days 1-5. The dose of cedazuridine was escalated first and decitabine was escalated once CDA inhibition by cedazuridine approached the maximum effect. The drug dose was escalated if mean decitabine area under the curve (AUC) of the oral drug was less than 90% of that for intravenous decitabine in the cohort and if no dose-limiting toxicity was observed. Dose-limiting toxicity was defined as a grade 3 or greater non-haematologic toxicity or grade 4 haematologic toxicity lasting more than 14 days and unrelated to the underlying disease. Once the decitabine AUC target range set as the primary endpoint, and established with intravenous decitabine, was reached at a dose deemed to be safe, the cohort that most closely approximated intravenous decitabine exposure was expanded to 18 evaluable patients. The primary objectives were to assess the safety of decitabine plus cedazuridine, and to determine the dose of each drug needed to achieve a mean AUC for decitabine exposure similar to that for intravenous decitabine exposure. This study is registered with ClinicalTrials.gov, number NCT02103478. FINDINGS: Between Oct 28, 2014, and Nov 13, 2015, we enrolled 44 eligible patients (of 75 screened) with previously treated or newly diagnosed myelodysplastic syndromes or chronic myelomonocytic leukaemia; 43 of the enrolled patients were evaluable. Participants were treated in five cohorts: cohorts 1-4 included six evaluable patients each; cohort 5 included 19 patients in a 13-patient expansion. Dose-dependent increases in decitabine AUC and peak plasma concentration occurred with each cohort dose escalation. There was no evident increase in toxicity compared with that reported for intravenous decitabine. Decitabine 30 mg and 40 mg plus cedazuridine 100 mg produced mean day-5 decitabine AUCs (146 ng × h/mL for decitabine 30 mg, and 221 ng × h/mL for decitabine 40 mg) closest to the mean intravenous-decitabine AUC (164 ng × h/mL). The most common grade 3 or more adverse events were thrombocytopenia (18 [41%] of 44 patients), neutropenia (13 [30%]), anaemia (11 [25%]), leukopenia (seven [16%]), febrile neutropenia (seven [16%]), and pneumonia (seven [16%]). Four (9%) patients died because of adverse events, none of which was considered drug related, and three (7%) patients died more than 30 days after discontinuing treatment because of progressive disease (two [5%]) and respiratory failure (one [2%]). INTERPRETATION: Oral decitabine plus cedazuridine emulated the pharmacokinetics of intravenous decitabine, with a similar safety profile and dose-dependent demethylation. Clinical responses were similar to intravenous decitabine treatment for 5 days. Further study of decitabine plus cedazuridine as an alternative to parenteral therapy or in combination with other new oral agents for myeloid disorders is warranted. FUNDING: Astex Pharmaceuticals, Inc.

The long non-coding RNA LINC00941 and SPRR5 are novel regulators of human epidermal homeostasis.

Several long non-coding RNAs (lncRNAs) act as regulators of cellular homeostasis; however, few of these molecules were functionally characterized in a mature human tissue environment. Here, we report that the lncRNA LINC00941 is a crucial regulator of human epidermal homeostasis. LINC00941 is enriched in progenitor keratinocytes and acts as a repressor of keratinocyte differentiation. Furthermore, LINC00941 represses SPRR5, a previously uncharacterized molecule, which functions as an essential positive regulator of keratinocyte differentiation. Interestingly, 54.8% of genes repressed in SPRR5-deficient epidermal tissue are induced in LINC00941-depleted organotypic epidermis, suggesting a common mode of action for both molecules.

A phase 1 trial of vadastuximab talirine combined with hypomethylating agents in patients with CD33-positive AML.

Treatment of acute myeloid leukemia (AML) among the elderly is challenging because of intolerance of intensive therapy and therapy-resistant biology. Hypomethylating agents (HMAs) are commonly used, with suboptimal outcomes. Vadastuximab talirine is a CD33-directed antibody conjugated to pyrrolobenzodiazepine (PBD) dimers. Preclinically, HMAs followed by vadastuximab talirine produced upregulated CD33 expression, increased DNA incorporation by PBD, and enhanced cytotoxicity. A combination cohort in a phase 1 study (NCT01902329) assessed safety, tolerability, and activity of vadastuximab talirine with HMAs. Those eligible had Eastern Cooperative Oncology Group status 0 to 1 and previously untreated CD33-positive AML, and declined intensive therapy. Vadastuximab talirine was administered intravenously at 10 µg/kg on last day of HMA (azacitidine or decitabine) infusion in 4-week cycles. Among 53 patients treated, the median age was 75 years. Patients had adverse (38%) or intermediate (62%) cytogenetic risk. Median treatment duration was 19.3 weeks. No dose-limiting toxicities were reported. The majority of adverse events were a result of myelosuppression, with some causing therapy delays. Thirty- and 60-day mortality rates were 2% and 8%, respectively. The composite remission rate (complete remission [CR] and CR with incomplete blood count recovery) was 70%. Fifty-one percent of remissions were minimal residual disease-negative by flow cytometry. Similarly high remission rates were observed in patients with secondary AML, aged at least 75 years, and with adverse cytogenetic risk. Median relapse-free survival and overall survival were 7.7 and 11.3 months, respectively. Compared with historical data for HMA monotherapy, the combination of vadastuximab talirine with HMAs produced a high remission rate, but was accompanied by increased hematologic toxicity.

A phase 1 trial of vadastuximab talirine as monotherapy in patients with CD33-positive acute myeloid leukemia.

Vadastuximab talirine (SGN-CD33A, 33A) is an antibody-drug conjugate consisting of pyrrolobenzodiazepine dimers linked to a monoclonal antibody targeting CD33, which is expressed in the majority of acute myeloid leukemia (AML) patients. This phase 1 study evaluated the safety, pharmacokinetics, and preliminary activity of vadastuximab talirine and determined the recommended monotherapy dose in patients with relapsed or refractory AML. Additional expansion cohorts tested vadastuximab talirine in specific subpopulations of relapsed AML, and in a cohort of older, treatment-naive patients. Patients received vadastuximab talirine IV on day 1 (5-60 µg/kg) or on days 1 and 4 (20 µg/kg) of 21-day cycles. A total of 131 patients (median age, 73 years [range, 26-89 years]) had intermediate I-II (48%) or adverse (34%) risk by European LeukemiaNet classification; 50% of patients had underlying myelodysplasia. Two dose-limiting toxicities (grade 2 pulmonary embolism and grade 4 hypocellular marrow) occurred during dose finding. Most adverse events (AEs) were consistent with myelosuppression; nonhematologic AEs included fatigue, nausea, and diarrhea. The 30-day mortality was 8%. At the recommended monotherapy dose of 40 µg/kg, the complete remission + CRi rate was 28% (5 of 18 patients); 50% of patients who responded achieved minimal residual disease negativity. In patients across dose levels who achieved CR or CRi, the median time to full count recovery was 6.4 weeks for neutrophils (≥1000/µL) and 10.6 weeks for platelets (≥100 × 109/L). Vadastuximab talirine demonstrates activity and a tolerable safety profile as a single agent in patients with AML. The recommended monotherapy dose of vadastuximab talirine is 40 µg/kg. This trial was registered at www.clinicaltrials.gov as # NCT01902329.

Hyper-CVAD plus nelarabine in newly diagnosed adult T-cell acute lymphoblastic leukemia and T-lymphoblastic lymphoma.

Nelarabine, a water soluble prodrug of 9-ß-D-arabinofuranosylguanine (ara-G), is a T-cell specific purine nucleoside analogue. Given its activity in relapsed and refractory T acute lymphoblastic leukemia (T-ALL) and T lymphoblastic lymphoma (T-LBL), we sought to define its role in the frontline treatment of adult patients. Therefore, we conducted a single arm phase 2 study to determine the safety and efficacy of nelarabine in combination with hyper-CVAD in newly diagnosed patients. For induction/consolidation, patients received eight cycles of hyper-CVAD alternating with high-dose methotrexate and cytarabine plus two cycles of nelarabine given at a dose of 650 mg/m2 intravenously daily for 5 days. This was followed by thirty months of POMP maintenance chemotherapy with two additional cycles of nelarabine given instead of cycles 6 and 7 of POMP maintenance. Sixty-seven patients, including 40 with T-ALL and 26 with T-LBL, were enrolled. Complete response rates in both T-ALL and T-LBL were 87% and 100% respectively. Grade 3 to 4 neurotoxic adverse events were reported in 5 patients. There were 21 relapses (31%) including 2 after allogeneic stem cell transplantation. Median duration of follow-up was 42.5 months. The 3-year complete remission duration (CRD) and overall survival (OS) rates were 66% and 65%, respectively. Compared to our historic hyper-CVAD data, there was no survival benefit with the addition of nelarabine. In conclusion, hyper-CVAD plus nelarabine was well tolerated and active in the frontline treatment of adult T-ALL/LBL patients.

The role of combined fludarabine, cyclophosphamide and rituximab chemoimmunotherapy in chronic lymphocytic leukemia: current evidence and controversies.

Chemoimmunotherapy (CIT) has become a cornerstone in the treatment of patients with chronic lymphocytic leukemia (CLL). The combination of fludarabine, cyclophosphamide and rituximab (FCR) has emerged as the standard of care for therapy of previously untreated patients with CLL who are younger than 65 years and have no significant comorbidities. In this article, we review the role of FCR in the current treatment paradigm for CLL.

Safety, efficacy, and clinical utility of asparaginase in the treatment of adult patients with acute lymphoblastic leukemia.

Adults with acute lymphoblastic leukemia (ALL) are known to have inferior outcomes compared to the pediatric population. Although the reasons for this are likely manyfold, the agents utilized and the increased intensity of pediatric treatments compared to adult treatments are likely significant contributing factors. Asparaginase, an enzyme that converts asparagine to aspartic acid, forms the backbone of almost all pediatric regimens and works by depleting extracellular asparagine, which ALL cells are unable to synthesize. Asparaginase toxicities, which include hypersensitivity reactions, pancreatitis, liver dysfunction, and thrombosis, have hindered its widespread use in the adult population. Here, we review the toxicity and efficacy of asparaginase in adult patients with ALL. With the proper precautions, it is a safe and effective agent in the treatment of younger adults with ALL with response rates in the frontline setting ranging from 78% to 96%, compared to most trials showing a 4-year overall survival of 50% or better. The age cutoff for consideration of treatment with pediatric-inspired regimens is not clear, but recent studies show promise particularly in the adolescent and young adult population. New formulations of asparaginase are actively in development, including erythrocyte-encapsulated asparaginase, which is designed to minimize the toxicity and improve the delivery of the drug.

Long-term outcome of acute promyelocytic leukemia treated with all-trans-retinoic acid, arsenic trioxide, and gemtuzumab.

The combination of all-trans-retinoic acid (ATRA) plus arsenic trioxide (ATO) has been shown to be superior to ATRA plus chemotherapy in the treatment of standard-risk patients with newly diagnosed acute promyelocytic leukemia (APL). A recent study demonstrated the efficacy of this regimen with added gemtuzumab ozogamicin (GO) in high-risk patients. We examined the long-term outcome of patients with newly diagnosed APL treated at our institution on 3 consecutive prospective clinical trials, using the combination of ATRA and ATO, with or without GO. For induction, all patients received ATRA (45 mg/m2 daily) and ATO (0.15 mg/kg daily) with a dose of GO (9 mg/m2 on day 1) added to high-risk patients (white blood cell count, >10 × 109/L), as well as low-risk patients who experienced leukocytosis during induction. Once in complete remission, patients received 4 cycles of ATRA plus ATO consolidation. One hundred eighty-seven patients, including 54 with high-risk and 133 with low-risk disease, have been treated. The complete remission rate was 96% (52 of 54 in high-risk and 127 of 133 in low-risk patients). Induction mortality was 4%, with only 7 relapses. Among low-risk patients, 60 patients (45%) required either GO or idarubicin for leukocytosis. Median duration of follow-up was 47.6 months. The 5-year event-free, disease-free, and overall survival rates are 85%, 96%, and 88%, respectively. Late hematological relapses beyond 1 year occurred in 3 patients. Fourteen deaths occurred beyond 1 year; 12 were related to other causes. This study confirms the durability of responses with this regimen.

Phase 2 study of low-dose clofarabine plus cytarabine for patients with higher-risk myelodysplastic syndrome who have relapsed or are refractory to hypomethylating agents.

BACKGROUND: The outcome of patients with higher-risk myelodysplastic syndromes (MDS) after hypomethylating agent (HMA) failure is poor. This study evaluated the safety and activity of a combination of low-dose clofarabine and cytarabine for these patients. METHODS: Seventy patients with higher-risk MDS who had no response, progressed, or relapsed after at least 4 cycles of HMA therapy were treated. RESULTS: The median age was 72 years. Thirty-nine percent of the patients had high-risk disease according to the International Prognostic Scoring System, and 50% of the patients had poor-risk cytogenetics. Twenty-three percent of the patients had therapy-related MDS. The median number of prior cycles of HMA was 6 (range, 4-45). The overall response rate was 44%. The 6-week mortality rate was 9%. Grade 3 and higher nonhematologic toxicities were rare, but infections occurred in 52% of the patients, and fever of unknown origin occurred in 33%. The median overall survival (OS) was 10 months (95% confidence interval, 1-37 months). Thirteen percent of the patients underwent allogeneic stem cell transplantation. The responding patients had a median OS of 22 months, whereas the nonresponding patients had a median OS of 4 months. A complex karyotype was associated with worse response rates and OS. CONCLUSIONS: The combination of low-dose clofarabine and cytarabine is clinically active in these patients with few treatment options. Cancer 2017;123:629-637. © 2016 American Cancer Society.

Long-term durable remission by cladribine followed by rituximab in patients with hairy cell leukaemia: update of a phase II trial.

Nucleoside analogues are highly active in patients with hairy cell leukaemia (HCL); however, patients continue to relapse. This phase II study evaluated the efficacy and safety of cladribine followed by rituximab in patients with untreated HCL (N = 59), relapsed HCL (N = 14) and HCL variant (HCLv, N = 7). Cladribine 5·6 mg/m(2) was given intravenously (IV) daily for 5 d and was followed approximately 1 month later with rituximab 375 mg/m(2) IV weekly for 8 weeks. Complete response rate in patients with untreated HCL, relapsed HCL and HCLv was 100%, 100% and 86%, respectively. With a median follow up of 60 months, 5-year failure-free survival (FFS) in patients with untreated HCL, relapsed HCL and HCLv was 95%, 100% and 64%, respectively. Median duration of response to the cladribine followed by rituximab was significantly longer than the first-line cladribine single agent in patients who received this treatment as second-line treatment (72 months vs not reached, P = 0·004). Almost all patients (94%) achieved negative minimal residual disease (MRD) after the treatment. Positive MRD during the follow up did not necessarily result in clinically relevant relapse. Cladribine followed by rituximab is highly effective even in patients with relapsed disease and HCLv, and can achieve durable remission.

Phase I study of evofosfamide, an investigational hypoxia-activated prodrug, in patients with advanced leukemia.

Tumor hypoxia causes resistance to radiation and chemotherapy. Evofosfamide (TH-302) has exhibited specific hypoxia-dependent cytotoxicity against primary acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML) samples in vitro. Based on these findings, a Phase I study of evofosfamide was designed for patients with relapsed/refractory leukemia (NCT01149915). In this open-label study, patients were treated with evofosfamide as a 30-60 min/day infusion on Days 1-5 of a 21-day cycle (Arm A, n = 38) or as a continuous infusion over 120 hr over Days 1-5 of a 21-day cycle (Arm B, n = 11). Forty-nine patients were treated including 39 (80%) with AML and 9 (18%) with ALL. Patients had received a median of five prior therapies. In Arm A, the dose-limiting toxicities (DLTs) were grade 3 esophagitis, observed at a dose of 550 mg/m(2) . The maximum tolerated dose (MTD) was a daily dose of 460 mg/m(2) . In Arm B, the DLTs were grade 3 stomatitis and hyperbilirubinemia, observed at a daily dose of 460 mg/m(2) . The continuous infusion MTD was a daily dose of 330 mg/m(2) . Hypoxia markers HIF-1α and CAIX were highly expressed in leukemic bone marrow and were significantly reduced after evofosfamide therapy. The combined overall response rate in Arms A and B was 6% (2 CR/CRi and 1 PR), with all responses seen in Arm A. Evofosfamide has shown limited activity in heavily pretreated leukemia patients. Further evaluation investigating evofosfamide in combination with cytotoxic or demethylating agents is warranted. Am. J. Hematol. 91:800-805, 2016. © 2016 Wiley Periodicals, Inc.

At High Levels, Constitutively Activated STAT3 Induces Apoptosis of Chronic Lymphocytic Leukemia Cells.

In chronic lymphocytic leukemia (CLL), the increment in PBLs is slower than the expected increment calculated from the cells' proliferation rate, suggesting that cellular proliferation and apoptosis are concurrent. Exploring this phenomenon, we found overexpression of caspase-3, higher cleaved poly (ADP-ribose) polymerase levels (p < 0.007), and a higher apoptosis rate in cells from patients with high counts compared with cells from patients with low counts. Although we previously found that STAT3 protects CLL cells from apoptosis, STAT3 levels were significantly higher in cells from patients with high counts than in cells from patients with low counts. Furthermore, overexpression of STAT3 did not protect the cells. Rather, it upregulated caspase-3 and induced apoptosis. Remarkably, putative STAT3 binding sites were identified in the caspase-3 promoter, and a luciferase assay, chromatin immunoprecipitation, and an EMSA revealed that STAT3 activated caspase-3 However, caspase-3 levels increased only when STAT3 levels were sufficiently high. Using chromatin immunoprecipitation and EMSA, we found that STAT3 binds with low affinity to the caspase-3 promoter, suggesting that at high levels, STAT3 activates proapoptotic mechanisms and induces apoptosis in CLL cells.