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.

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.

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.

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.

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.

Eradication of bone marrow minimal residual disease may prompt early treatment discontinuation in CLL.

The high complete remission rate with first-line combined fludarabine, cyclophosphamide, and rituximab (FCR) begs the question of the value of minimal residual disease (MRD)-negative status as a treatment end point. We report on 237 patients with chronic lymphocytic leukemia who received first-line FCR. MRD was prospectively assessed by 4-color flow cytometry in bone marrow after course 3 and at final response assessment. After course 3 and at final response assessment, 17% and 43% of patients were MRD negative in bone marrow, respectively. A mutated immunoglobulin heavy chain variable gene and trisomy 12 were independently associated with MRD-negative status both after 3 courses of FCR and at final response assessment in multivariable analyses (MVAs). MRD-negative status was independently associated with significantly longer progression-free survival (PFS) and overall survival (OS) in MVA (P = .03 and .02, respectively). This association was confirmed also on landmark MVA at the time of MRD assessment (P = .04 and .05, respectively). MRD-negative patients had comparable PFS and OS, independent of the number of courses received or interim staging. Early MRD eradication may be a desirable goal, prompting consideration of early discontinuation of treatment. This trial was registered at www.clinicaltrials.gov as #NCT00759798.

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.

Prognostic impact of persistent cytogenetic abnormalities at complete remission in adult patients with acute lymphoblastic leukemia.

In acute myelogenous leukemia, the persistent detection of abnormal cytogenetics at complete remission (ACCR) is associated with inferior outcomes. However, the prognostic significance of ACCR in adult patients with acute lymphoblastic leukemia (ALL) is unknown. We evaluated 272 adult patients with ALL and abnormal cytogenetics at baseline who were treated with frontline induction chemotherapy, achieved complete remission (CR) and had cytogenetic analysis performed at the time of CR. ACCR was observed in 26 patients (9.6%). Median relapse-free survival was 22 months (95% CI, 12 months to not reached) for patients with ACCR vs. 48 months (range, 30-125 months) in patients with normal cytogenetics at CR (NCCR; P = 0.31). Median overall survival also did not differ significantly between the ACCR (99 months [range, 17 months to not reached]) and NCCR groups (67 months [range, 47 months to not reached], P = 0.86). The specificity of ACCR for minimal residual disease (MRD) positivity by multi-parameter flow cytometry (MFC) was 43%, and there was overall poor correlation between these two methods for the detection of residual disease. When patients were stratified by MRD status, the presence or absence of persistent cytogenetic abnormalities at CR did not add additional prognostic information. This study suggests that there is poor association between MRD assessment by MFC and the presence or absence of cytogenetic abnormalities at CR in adult patients with ALL. ACCR was not associated with adverse outcomes in ALL and did not add additional prognostic information when MRD status by MFC was known.

Combination of hyper-CVAD with ponatinib as first-line therapy for patients with Philadelphia chromosome-positive acute lymphoblastic leukaemia: a single-centre, phase 2 study.

BACKGROUND: Combination of chemotherapy with a tyrosine-kinase inhibitor is effective in the treatment of Philadelphia chromosome-positive acute lymphoblastic leukaemia. Ponatinib is a more potent BCR-ABL1 inhibitor than all other tyrosine-kinase inhibitors and selectively suppresses the resistant T315I clones. We examined the activity and safety of combining chemotherapy with ponatinib for patients with Philadelphia chromosome-positive acute lymphoblastic leukaemia in this continuing phase 2 trial. METHODS: In this single-centre, phase 2, single-arm trial, adult patients with previously untreated Philadelphia chromosome-positive acute lymphoblastic leukaemia were sequentially enrolled. Patients who had received fewer than two courses of previous chemotherapy with or without tyrosine-kinase inhibitors were also eligible. Patients had to be aged 18 years or older, have an Eastern Cooperative Oncology Group performance status of 2 or less, have normal cardiac function (defined by ejection fraction above 50%), and have adequate organ function (serum bilirubin ≤3·0 mg/dL and serum creatinine ≤3·0 mg/dL, unless higher concentrations were believed to be due to a tumour). Patients received eight cycles of hyperfractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone (hyper-CVAD) alternating with high-dose methotrexate and cytarabine every 21 days. Ponatinib 45 mg was given daily for the first 14 days of cycle 1 then continuously for the subsequent cycles. Patients in complete remission received maintenance with ponatinib 45 mg daily with vincristine and prednisone monthly for 2 years followed by ponatinib indefinitely. The primary endpoint for this study was event-free survival. The trial is registered at ClinicalTrials.gov, number NCT01424982. FINDINGS: 37 patients were enrolled and treated from Nov 1, 2011, to Sept 1, 2013. 2-year event-free survival rate was 81% (95% CI 64-90). Grade 3 or more toxic effects included infections during induction (20 [54%] patients), increased aspartate aminotransferase and alanine aminotransferase concentration (14 [38%] patients), thrombotic events (three [8%]), myocardial infarction (three [8%]), hypertension (six [16%]), skin rash (eight [22%]), and pancreatitis (six [16%] patients). Two patients died from from myocardial infarction potentially related to treatment; another patient also died from myocardial infarction related to sepsis. Two further patients died, one from bleeding and another from infection, both deemed unrelated to treatment. INTERPRETATION: The first results of this ongoing trial indicate that the combination of chemotherapy with ponatinib is effective in achieving early sustained remissions in patients with newly diagnosed Philadelphia chromosome-positive acute lymphoblastic leukaemia. New strategies, including dosing titration of ponatinib and optimised control of vascular risk factors, might further improve outcomes. FUNDING: ARIAD Pharmaceuticals Inc.

Fludarabine, cyclophosphamide, and multiple-dose rituximab as frontline therapy for chronic lymphocytic leukemia.

BACKGROUND: Fludarabine, cyclophosphamide, and rituximab (FCR) result in durable responses in patients with previously untreated chronic lymphocytic leukemia (CLL). Previous reports have suggested that in patients with relapsed CLL, a dose-intensified rituximab regimen increases response rates in comparison with standard-dose rituximab. It is unknown whether rituximab intensification of the FCR regimen will result in improved response rates and patient outcomes in patients with previously untreated CLL. METHODS: A single-arm study was conducted to evaluate the safety and efficacy of a modified FCR regimen with multiple-dose rituximab (FCR3) in 65 patients with previously untreated CLL. The results were compared with those for a historical cohort treated with FCR. RESULTS: The overall response rate to FCR3 was 97%, with 75% of the patients achieving a complete remission. Minimal residual disease negativity was achieved for 62% of the patients according to flow cytometry. The median time to progression (TTP) was 81 months, and the median overall survival (OS) was not reached, with 58% of the patients still alive at a median survivor follow-up of 9.7 years. Grade 3 or 4 neutropenia, grade 3 or 4 thrombocytopenia, and major infections were observed with 45%, 5%, and 1.9% of the FCR3 courses, respectively. Therapy-related myelodysplastic syndrome (t-MDS) or therapy-related acute myelogenous leukemia (t-AML) developed in 7 patients (11%; P < .01 vs the historical FCR cohort). CONCLUSIONS: In patients with previously untreated CLL, FCR3 resulted in response rates, TTP, and OS similar to those of a historical cohort of patients treated with FCR. FCR3 was associated with an increased incidence of t-MDS/t-AML.

Final results of a phase 2 trial of clofarabine and low-dose cytarabine alternating with decitabine in older patients with newly diagnosed acute myeloid leukemia.

BACKGROUND: The treatment of older adults with acute myeloid leukemia (AML) using standard intensive chemotherapy has been associated with poor outcomes. Effective, less toxic therapies are needed to achieve and maintain durable remissions. METHODS: One hundred eighteen patients with newly diagnosed AML (median age, 68 years; range, 60-81 years) were treated with a regimen of clofarabine and low-dose cytarabine (LDAC) alternating with decitabine (DAC). The induction consisted of intravenous clofarabine at 20 mg/m(2) on days 1 to 5 combined with subcutaneous LDAC at 20 mg twice daily on days 1 to 10. Responding patients were then treated with a prolonged consolidation/maintenance regimen consisting of cycles of clofarabine plus LDAC alternating with cycles of DAC. RESULTS: The overall response rate was 68%. The complete remission (CR) rate was 60% overall, 71% for patients with a diploid karyotype, and 50% for patients with an adverse karyotype. The median overall survival (OS) was 11.1 months for all patients and 18.5 months for those achieving a CR/complete remission with incomplete platelet recovery (CRp). The median relapse-free survival for patients achieving a CR/CRp was 14.1 months. According to a multivariate analysis, only adverse cytogenetics and a white blood cell count ≥ 10 × 10(9)/L predicted worse OS. The regimen was well tolerated with 4- and 8-week mortality rates of 3% and 7%, respectively. The most common nonhematologic adverse events were nausea, elevated liver enzymes, and rash. CONCLUSIONS: The lower intensity, prolonged-therapy program of clofarabine and LDAC alternating with DAC is well tolerated and highly effective in older patients with AML.

Long-term follow-up of a phase 2 study of chemotherapy plus dasatinib for the initial treatment of patients with Philadelphia chromosome-positive acute lymphoblastic leukemia.

BACKGROUND: The long-term efficacy of a combination of chemotherapy and dasatinib in patients with Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL) is not well established. METHODS: Patients received dasatinib with 8 cycles of alternating hyperfractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone and high-dose cytarabine and methotrexate. Patients in complete remission (CR) continued maintenance dasatinib, vincristine, and prednisone for 2 years, which was followed by dasatinib indefinitely. Patients eligible for allogeneic stem cell transplantation (SCT) received it during their first CR. RESULTS: Seventy-two patients with a median age of 55 years (range, 21-80 years) were treated; 69 (96%) achieved CR. Among them, 57 (83%) achieved cytogenetic CR after 1 cycle, and 64 (93%) achieved a major molecular response at a median of 4 weeks (range, 2-38 weeks). Sixty-five patients (94%) were negative for minimal residual disease assessed by flow cytometry at a median of 3 weeks (range, 2-37 weeks). Dasatinib-related grade 3 and 4 adverse events included bleeding, pleural/pericardial effusions, and elevated transaminases. With a median follow-up of 67 months (range, 33-97 months), 33 patients (46%) were alive, and 30 (43%) were in CR; 12 underwent allogeneic SCT. Thirty-nine patients died (3 at induction, 19 after relapse, 7 after SCT performed during first CR, and 10 during CR). The median disease-free survival and overall survival were 31 (range, 0.3-97 months) and 47 months (range, 0.2-97 months), respectively. Seven relapsed patients had BCR-ABL kinase domain mutations, including 4 with T315I. CONCLUSIONS: A combination of chemotherapy with dasatinib is effective in achieving long-term remission for patients with newly diagnosed Ph + ALL.

Phase 2 study of azacytidine plus sorafenib in patients with acute myeloid leukemia and FLT-3 internal tandem duplication mutation.

Patients received 5-azacytidine (AZA) 75 mg/m(2) intravenously daily for 7 days and sorafenib 400 mg orally twice daily continuously; cycles were repeated at ~1-month intervals. Forty-three acute myeloid leukemia (AML) patients with a median age of 64 years (range, 24-87 years) were enrolled; 37 were evaluable for response. FMS-like tyrosine kinase-3 (FLT3)-internal tandem duplication (ITD) mutation was detected in 40 (93%) patients, with a median allelic ratio of 0.32 (range, 0.009-0.93). They had received a median of 2 prior treatment regimens (range, 0-7); 9 had failed prior therapy with a FLT3 kinase inhibitor. The response rate was 46%, including 10 (27%) complete response with incomplete count recovery (CRi), 6 (16%) complete responses (CR), and 1 (3%) partial response. The median time to achieve CR/CRi was 2 cycles (range, 1-4), and the median duration of CR/CRi was 2.3 months (range, 1-14.3 months). Sixty-four percent of patients achieved adequate (defined as >85%) FLT3 inhibition during their first cycle of therapy. The degree of FLT3 inhibition correlated with plasma sorafenib concentrations. FLT3 ligand levels did not rise to levels seen in prior studies of patients receiving cytotoxic chemotherapy. The combination of AZA and sorafenib is effective for patients with relapsed AML and FLT-3-ITD. This trial was registered at clinicaltrials.gov as #NCT01254890.

Detection of MRD may predict the outcome of patients with Philadelphia chromosome-positive ALL treated with tyrosine kinase inhibitors plus chemotherapy.

From 2001 to 2011, 122 patients with newly diagnosed Philadelphia chromosome-positive acute lymphoblastic leukemia were treated with chemotherapy + imatinib (n = 54) or + dasatinib (n = 68). One hundred fifteen (94%) achieved complete remission (CR) including 101 patients who achieved it with only 1 induction course and had at least 1 minimal residual disease (MRD) assessment; 25 patients underwent an allogeneic stem cell transplant in first CR and were excluded, leaving 76 patients as the subject of this report. MRD monitoring by multiparameter flow cytometry (MFC) and real-time quantitative polymerase chain reaction (PCR) was performed at the end of induction and at ~3-month intervals thereafter. Median age was 54 years (range, 21-84 years). There was no difference in survival by achievement of at least a major molecular response (MMR; BCR-ABL/ABL < 0.1%) at CR (P = .22). Patients achieving MMR at 3, 6, 9, and 12 months had a better survival (P = .02, .04, .05, and .01, respectively). Negative MFC at CR did not predict for improved survival (P = .2). At 3 and 12 months, negative MRD by MFC was associated with improved survival (P = .04 and .001). MRD monitoring by PCR and MFC identifies patients who benefit from treatment intensification in first CR.

Phase I/II study of the hypoxia-activated prodrug PR104 in refractory/relapsed acute myeloid leukemia and acute lymphoblastic leukemia.

We previously demonstrated vast expansion of hypoxic areas in the leukemic microenvironment and provided a rationale for using hypoxia-activated prodrugs. PR104 is a phosphate ester that is rapidly hydrolyzed in vivo to the corresponding alcohol PR-104A and further reduced to the amine and hydroxyl-amine nitrogen mustards that induce DNA cross-linking in hypoxic cells under low oxygen concentrations. In this phase I/II study, patients with relapsed/refractory acute myeloid leukemia (n=40) after 1 or 2 prior treatments or acute lymphoblastic leukemia (n=10) after any number of prior treatments received PR104; dose ranged from 1.1 to 4 g/m(2). The most common treatment-related grade 3/4 adverse events were myelosuppression (anemia 62%, neutropenia 50%, thrombocytopenia 46%), febrile neutropenia (40%), infection (24%), and enterocolitis (14%). Ten of 31 patients with acute myeloid leukemia (32%) and 2 of 10 patients with acute lymphoblastic leukemia (20%) who received 3 g/m(2) or 4 g/m(2) had a response (complete response, n=1; complete response without platelet recovery, n=5; morphological leukemia-free state, n=6). The extent of hypoxia was evaluated by the hypoxia tracer pimonidazole administered prior to a bone marrow biopsy and by immunohistochemical assessments of hypoxia-inducible factor alpha and carbonic anhydrase IX. A high fraction of leukemic cells expressed these markers, and PR104 administration resulted in measurable decrease of the proportions of hypoxic cells. These findings indicate that hypoxia is a prevalent feature of the leukemic microenvironment and that targeting hypoxia with hypoxia-activated prodrugs warrants further evaluation in acute leukemia. The trial is registered at clinicaltrials.gov identifier: 01037556.

HCVAD plus imatinib or dasatinib in lymphoid blastic phase chronic myeloid leukemia.

BACKGROUND: Chronic myeloid leukemia (CML) may progress to blast phase (BP) at the rate of 1% to 1.5% per year. With the use of single-agent tyrosine kinase inhibitors, median overall survival ranges between 7 and 11 months. METHODS: The outcome was analyzed for 42 patients with lymphoid BP-CML who were treated with hyperfractionated cyclophosphamide, vincristine, Adriamycin, dexamethasone (HCVAD) plus imatinib or dasatinib. RESULTS: Complete hematological response was achieved in 90% of patients, complete cytogenetic remission in 58%, and complete molecular remission in 25%. Flow cytometry minimal residual disease negativity was achieved by 42% of evaluable patients after induction. Eighteen patients received allogeneic stem cell transplant (SCT) while in first complete hematological response. Median remission duration was 14 months and was longer among SCT recipients (P = .01) on multivariate analysis. Median overall survival was 17 months (range, 7-27 months) and was longer among SCT recipients (P < .001) and patients treated with dasatinib (P = .07) on multivariate analysis. Although a high rate of hematologic toxicity (100%) and infectious complications (59%) were observed, the related rate of treatment discontinuation was low (7% and 9%, respectively). CONCLUSIONS: HCVAD combined with tyrosine kinase inhibitors is an effective regimen for the management of BP-CML, particularly when followed by allogeneic SCT.

Epigenetic therapy is associated with similar survival compared with intensive chemotherapy in older patients with newly diagnosed acute myeloid leukemia.

We reviewed the outcome of 671 patients 65 years of age or older with newly diagnosed acute myeloid leukemia (AML) treated at our institution between 2000 and 2010 with intensive chemotherapy (n = 557) or azacitidine- or decitabine-based therapy (n = 114). Both groups were balanced according to cytogenetics and performance status. The complete response rates with chemotherapy and epigenetic therapy were 42% and 28%, respectively (P = .001), and the 8-week mortality 18% and 11%, respectively (P = .075). Two-year relapse-free survival rates (28% vs 39%, P = .843) and median survival (6.7 vs 6.5 months, P = .413) were similar in the 2 groups. Multivariate analysis identified older age, adverse cytogenetics, poor performance status, elevated creatinine, peripheral blood and BM blasts, and hemoglobin, but not type of AML therapy, as independent prognostic factors for survival. No outcome differences were observed according to cytogenetics, FLT3 mutational status, age, or performance status by therapy type. Decitabine was associated with improved median overall survival compared with azacitidine (5.5 vs 8.8 months, respectively, P = .03). Survival after failure of intensive chemotherapy, azacitidine, or decitabine was more favorable in patients who had previously received decitabine (1.1 vs 0.9 vs 3.1 months, respectively, P = .109). The results of the present study show that epigenetic therapy is associated with similar survival rates as intensive chemotherapy in older patients with newly diagnosed AML. The studies reviewed are registered at www.clinicaltrials.gov as 2009-0172 (NCT00926731) and 2009-0217 (NCT00952588).