Patricia A. Walker

Dual epigenetic targeting with panobinostat and azacitidine in acute myeloid leukemia and high-risk myelodysplastic syndrome.

Therapeutic options are limited for elderly patients with acute myeloid leukemia (AML). A phase Ib/II study was undertaken to evaluate the maximum-tolerated dose (MTD) and preliminary efficacy of the pan-histone deacetylase inhibitor panobinostat (LBH589) in combination with azacitidine in patients with AML or high-risk myelodysplastic syndrome (MDS) naïve to intensive chemotherapy. Thirty-nine patients (AML=29, MDS=10) received azacitidine 75 mg/m2 subcutaneously (days 1–5) and oral panobinostat (starting on day 5, thrice weekly for seven doses) in 28-day cycles until toxicity or disease progression. Dose-limiting toxicities during the phase Ib stage were observed in 0/4 patients receiving 10 mg panobinostat, in 1/7 patients (fatigue) receiving 20 mg, in 1/6 patients (fatigue) receiving 30 mg and in 4/5 patients (fatigue, syncope, hyponatremia and somnolence) receiving 40 mg. In phase II, an additional 17 patients received panobinostat at a MTD of 30 mg. The overall response rate (ORR=CR+CRi+PR) in patients with AML was 31% (9/29) and that in patients with MDS was 50% (5/10). After a median follow-up of 13 months, the median overall survival was 8 and 16 months in patients with AML and MDS, respectively. Increased histone H3 and H4 acetylation was a useful early biomarker of clinical response. Combining panobinostat with azacitidine was tolerable and clinically active in high-risk MDS/AML patients, warranting further exploration.

Reducing TNF Receptor 2+ regulatory T cells via the combined action of azacitidine and the HDAC inhibitor panobinostat for clinical benefit in acute myeloid leukemia patients

Purpose: Acute myeloid leukemia (AML) provides an environment that enables immune suppression, resulting in functionally defective effector T cells; regulatory T cells (Treg) are significant contributors to the impaired antitumor immune response. As TNF is present at high levels in AML and TNF receptor-2 (TNFR2)–expressing Tregs identify highly functional Tregs, we examine the hypothesis that TNFR2+ Tregs are a relevant Treg subset in this cancer. We also determine the effect of the novel combinatorial therapy of the demethylating agent, azacitidine with the histone deacetylase inhibitor, panobinostat on Tregs, particularly TNFR2+ Tregs. Experimental Design: Thirty healthy donors and 14 patients with AML were enrolled in this study. Patients were treated with azacitidine and panobinostat for 28-day cycles. The frequency and functional relevance of TNFR2+ Tregs were analyzed subsequently. Results: We report that TNFR2+ Tregs are increased in AML and have a high migration potential toward the bone marrow. Furthermore, we demonstrate that the level of TNFR2+ Tregs in the peripheral blood and the bone marrow of patients are decreased in vivo after exposure to panobinostat and azacitidine. Reductions in TNFR2+ Tregs were associated with increases in Interferon (IFN)-γ and interleukin (IL)-2 production by effector T cells within the bone marrow and beneficial clinical responses. In vitro mechanistic studies indicated panobinostat as the primary driver for the reduction of Tregs. Conclusions: Our study provides for the first time, in vivo validation of the ability of panobinostat in combination with azacitidine to suppress prevalent TNFR2+ Tregs, resulting in clinical benefits within patients with AML. Clin Cancer Res; 20(3); 724–35. ©2013 AACR.

Consensus guidelines for the use of empiric and diagnostic-driven antifungal treatment strategies in haematological malignancy, 2014

Invasive fungal disease (IFD) causes significant morbidity and mortality in patients undergoing allogeneic haemopoietic stem cell transplantation or chemotherapy for haematological malignancy. Much of these adverse outcomes are due to the limited ability of traditional diagnostic tests (i.e. culture and histology) to make an early and accurate diagnosis. As persistent or recurrent fevers of unknown origin (PFUO) in neutropenic patients despite broad-spectrum antibiotics have been associated with the development of IFD, most centres have traditionally administered empiric antifungal therapy (EAFT) to patients with PFUO. However, use of an EAFT strategy has not been shown to have an overall survival benefit and is associated with excessive antifungal therapy use. As a result, the focus has shifted to developing more sensitive and specific diagnostic tests for early and more targeted antifungal treatment. These tests, including the galactomannan enzyme-linked immunosorbent assay and Aspergillus polymerase chain reaction (PCR), have enabled the development of diagnostic-driven antifungal treatment (DDAT) strategies, which have been shown to be safe and feasible, reducing antifungal usage. In addition, the development of effective antifungal prophylactic strategies has changed the landscape in terms of the incidence and types of IFD that clinicians have encountered. In this review, we examine the current role of EAFT and provide up-to-date data on the newer diagnostic tests and algorithms available for use in EAFT and DDAT strategies, within the context of patient risk and type of antifungal prophylaxis used.

Primary antifungal prophylaxis in adult patients with acute lymphoblastic leukaemia: a multicentre audit

OBJECTIVES The primary objectives were to investigate the prescribing practices of primary antifungal prophylaxis (PAP) and incidence of invasive fungal disease (IFD) in adult patients with ALL receiving induction-consolidation chemotherapy. Secondary objectives were to determine risk factors for IFD and resource utilization associated with IFD. METHODS A retrospective chart review of adult patients with ALL from commencement of induction until completion of consolidation chemotherapy was undertaken from January 2008 to June 2013 in four hospitals in Melbourne, Australia. IFD was classified according to the revised European Organisation for Research and Treatment of Cancer criteria. Cost analysis was performed from an Australian public hospital perspective. RESULTS Ninety-eight patients were included in the audit; 83 (85%) received PAP. Most patients (49/83, 59%) switched between two different antifungal agents, predominantly between liposomal amphotericin B and an azole. Five proven/probable and six possible IFD cases were identified. Proven/probable IFD was most common in patients receiving the BFM95 chemotherapy protocol. The incidence of proven/probable IFD was significantly lower in patients receiving PAP compared with those who did not (2/78, 2.6% versus 3/14, 21.4%; P = 0.024). For every five patients receiving PAP, one proven/probable IFD case would be prevented. Proven/probable IFD was associated with an additional median cost of 121,520 Australian dollars (95% CI: 90,781-180,141 Australian dollars; P < 0.001) compared with patients without IFD. CONCLUSIONS This is the first multicentre study evaluating PAP use in patients with ALL. With the caveats of interpretation of retrospective, non-randomized data, PAP was associated with a reduced IFD risk.

Fludarabine, cytarabine, granulocyte-colony stimulating factor and amsacrine: an effective salvage therapy option for acute myeloid leukemia at first relapse

Abstract Improved therapeutic options for relapsing patients with acute myeloid leukemia (AML) are urgently needed. Poor outcomes following salvage therapy have been reported in those with short initial remission duration, adverse risk karyotype, prior allograft, older age, FLT3-internal tandem duplication (ITD) AML and prior high-dose cytarabine (HiDAC) induction therapy. We present a cohort of 58 patients (aged 18–70) treated with fludarabine, cytarabine, granulocyte-colony stimulating factor (G-CSF) and amsacrine (FLAG-amsacrine) as salvage chemotherapy for AML at first relapse. 83% had received prior HiDAC-based therapy. The overall complete remission (CR/CR with incomplete blood count recovery [CRi]) rate was 59%, with median event-free survival (EFS) and overall survival (OS) of 6.9 and 10.6 months, respectively. FLAG-amsacrine was an effective bridge to allogeneic transplant with 38% successfully transplanted with excellent outcomes (median OS not reached). FLAG-amsacrine was also effective in elderly patients (≥60 years), with 61% achieving second remission. The regimen was well tolerated, with 30- and 42-day treatment-related mortality of 3.4% and 13.8%, respectively. Outcomes remained poor in those with short initial remission duration (<6 months). We conclude that FLAG-amsacrine is a useful salvage option for AML at first relapse.

Comparison of biosimilar filgrastim with originator filgrastim for peripheral blood stem cell mobilization and engraftment in patients with multiple myeloma undergoing autologous stem cell transplantation

Nivestim is a biosimilar approved for the same indications as Neupogen including the mobilization of autologous peripheral blood stem cells (PBSCs). The clinical efficacy and safety of Nivestim for this use have not been formally assessed in clinical trials.

Comparison of the probability of target attainment of anidulafungin against Candida spp. in patients with acute leukaemia.

This study aimed to investigate the probability of target attainment (PTA) of various anidulafungin dosing regimens against Candida spp. in patients with acute leukaemia. A Monte Carlo simulation was performed using a previously published population pharmacokinetic model. The following dosing scenarios were evaluated: 200 mg loading dose (LD) on Day 1 then 100 mg daily (manufacturers recommended dosing regimen); 200 mg LD on Day 1 then 100 mg every 48 h (q48 h); and 200 mg q48 h, 200 mg every 72 h (q72 h) and 300 mg q72 h. For each dosing regimen, free drug concentrations were calculated to evaluate the effect of 99% protein binding. The PTA at various pharmacodynamic (PD) targets was determined as the percentage of subjects who achieved a free drug area under the plasma concentration-time curve over the minimum inhibitory concentration ratio (ƒAUC/MIC) or a free drug maximum plasma concentration over the minimum inhibitory concentration ratio (ƒC(max)/MIC) above the PD targets. PTA expectation values were then calculated for each dosing regimen. The currently recommended dosing regimen of anidulafungin was not optimal for invasive candidiasis in patients with acute leukaemia. Alternate dosing strategies with higher doses and extended dosing intervals (intermittent dosing) achieved better target attainment. This is the first study to optimise therapy with anidulafungin using Monte Carlo simulation. These results provide a rationale in support of future clinical investigation of intermittent dosing of anidulafungin.

High-dose cytarabine (24 g/m2) in combination with idarubicin (HiDAC-3) results in high first-cycle response with limited gastrointestinal toxicity in adult acute myeloid leukaemia.

Although induction chemotherapy comprising high‐dose cytarabine (HiDAC) in combination with idarubicin and etoposide or ‘ICE’ for adult acute myeloid leukaemia (AML) produces a complete remission rate of nearly 80%, gastrointestinal toxicity is significant. Omission of etoposide may produce similar clinical outcomes with potentially less gastrointestinal toxicity.

Bortezomib-based antibody depletion for refractory autoimmune hematological diseases

Certain patients with antibody-mediated autoimmune disease exhibit poor responses to conventional immunosuppression, including B-cell depletion with rituximab. Proteasome inhibitors such as bortezomib demonstrate pleiotropic immunomodulatory effects, including direct toxicity to antibody-producing cells. Here, we report preliminary evidence for the efficacy of bortezomib as salvage therapy for refractory autoimmune hematological disease. Thirteen treatment episodes in 10 patients with autoimmune hematological phenomena (autoimmune hemolytic anemia [AIHA; n = 8], acquired hemophilia (n = 1), immune thrombocytopenia (n = 1), and thrombotic thrombocytopenic purpura [TTP; n = 3]) and a median of 5 (range, 3-12) prior lines of therapy demonstrated an overall response rate of 77% (10 of 13) including 38% (5 of 13) complete remissions. The majority of clinical improvements were rapid, correlated with biomarkers of autoantibody reduction, and were associated with an acceptable safety profile. Responses appeared durable following treatment of TTP and acquired hemophilia; AIHA responses were more limited with a pattern of relapse following bortezomib cessation. These data provide proof of concept for the utility of proteasome inhibition as antibody depletion therapy in autoimmune disease.

Adverse impact of high donor CD3+ cell dose on outcome following tandem auto-NMA allogeneic transplantation for high-risk myeloma

High-risk (HR) multiple myeloma (MM) has poor outcomes with conventional therapy. Tandem autologous-non-myeloablative (NMA) allogeneic stem cell transplantation (autologous stem cell transplantation (ASCT)-NMA allogeneic SCT) is potentially curative secondary to graft-versus-myeloma effect. We retrospectively analysed ASCT-NMA allogeneic SCT outcomes of 59 HR and relapsed MM patients. At a median follow-up of 35.8 months, the outcomes for HR-MM upfront tandem ASCT-NMA allogeneic SCT and standard-risk (SR) MM upfront ASCT alone were comparable (median PFS 1166 days versus 1465 days, P=0.36; median overall survival (OS) not reached in both cohorts, P=0.31). The 5-year PFS and OS of patients who had ASCT-NMA allogeneic SCT after relapsing from previous ASCT were 30% and 48% respectively. High CD3+ cell dose (>3 × 108/kg) infusion was associated with more acute GvHD (grade 2–4) (47% vs 17.5%; P=0.03), extensive chronic GvHD (80% vs 50%; P=0.04), increased transplant-related mortality (26.3% vs 5%; P=0.009) and inferior OS (median OS 752 days vs not reached; P=0.002). On multivariate analysis, response achieved with tandem transplant (<CR vs CR vs stringent CR; hazard ratio=5.54, confidence interval=2.67–11.5; P<0.0001) and CD3+ cell dose infused (hazard ratio=1.42; confidence interval=1.21–1.67; P<0.0001) emerged as factors influencing OS. We conclude that tandem ASCT-NMA allogeneic SCT is an effective therapy for HR or relapsed MM and that higher CD3+ doses have an adverse impact on transplant outcome.