Sequential azacitidine plus lenalidomide combination for elderly patients with untreated acute myeloid leukemia

A Combination of the Immunotherapeutic Drug Anti-Programmed Death 1 with Lenalidomide Enhances Specific T Cell Immune Responses against Acute Myeloid Leukemia Cells

Immune checkpoint inhibitors can block inhibitory molecules on the surface of T cells, switching them from an exhausted to an active state. One of these inhibitory immune checkpoints, programmed cell death protein 1 (PD-1) is expressed on T cell subpopulations in acute myeloid leukemia (AML). PD-1 expression has been shown to increase with AML progression following allo-haematopoeitic stem cell transplantation, and therapy with hypomethylating agents. We have previously shown that anti-PD-1 can enhance the response of leukemia-associated antigen (LAA)-specific T cells against AML cells as well as leukemic stem and leukemic progenitor cells (LSC/LPCs) ex vivo. In concurrence, blocking of PD-1 with antibodies such as nivolumab has been shown to enhance response rates post-chemotherapy and stem cell transplant. The immune modulating drug lenalidomide has been shown to promote anti-tumour immunity including anti-inflammatory, anti-proliferative, pro-apoptotic and anti-angiogenicity. The effects of lenalidomide are distinct from chemotherapy, hypomethylating agents or kinase inhibitors, making lenalidomide an attractive agent for use in AML and in combination with existing active agents. To determine whether anti-PD-1 (nivolumab) and lenalidomide alone or in combination could enhance LAA-specific T cell immune responses, we used colony-forming immune and ELISpot assays. Combinations of immunotherapeutic approaches are believed to increase antigen-specific immune responses against leukemic cells including LPC/LSCs. In this study we used a combination of LAA-peptides with the immune checkpoint inhibitor anti-PD-1 and lenalidomide to enhance the killing of LSC/LPCs ex vivo. Our data offer a novel insight into how we could improve AML patient responses to treatment in future clinical studies.

Biallelic TET2 mutations confer sensitivity to 5'-azacitidine in acute myeloid leukemia

Precision medicine can significantly improve outcomes for patients with cancer, but implementation requires comprehensive characterization of tumor cells to identify therapeutically exploitable vulnerabilities. Here, we describe somatic biallelic TET2 mutations in an elderly patient with acute myeloid leukemia (AML) that was chemoresistant to anthracycline and cytarabine but acutely sensitive to 5'-azacitidine (5'-Aza) hypomethylating monotherapy, resulting in long-term morphological remission. Given the role of TET2 as a regulator of genomic methylation, we hypothesized that mutant TET2 allele dosage affects response to 5'-Aza. Using an isogenic cell model system and an orthotopic mouse xenograft, we demonstrate that biallelic TET2 mutations confer sensitivity to 5'-Aza compared with cells with monoallelic mutations. Our data argue in favor of using hypomethylating agents for chemoresistant disease or as first-line therapy in patients with biallelic TET2-mutated AML and demonstrate the importance of considering mutant allele dosage in the implementation of precision medicine for patients with cancer.

Reshaping the tumor microenvironment: The versatility of immunomodulatory drugs in B-cell neoplasms

Immunomodulatory drugs (IMiDs) such as thalidomide, lenalidomide and pomalidomide are antitumor compounds that have direct tumoricidal activity and indirect effects mediated by multiple types of immune cells in the tumor microenvironment (TME). IMiDs have shown remarkable therapeutic efficacy in a set of B-cell neoplasms including multiple myeloma, B-cell lymphomas and chronic lymphocytic leukemia. More recently, the advent of immunotherapy has revolutionized the treatment of these B-cell neoplasms. However, the success of immunotherapy is restrained by immunosuppressive signals and dysfunctional immune cells in the TME. Due to the pleiotropic immunobiological properties, IMiDs have shown to generate synergetic effects in preclinical models when combined with monoclonal antibodies, immune checkpoint inhibitors or CAR-T cell therapy, some of which were successfully translated to the clinic and lead to improved responses for both first-line and relapsed/refractory settings. Mechanistically, despite cereblon (CRBN), an E3 ubiquitin ligase, is considered as considered as the major molecular target responsible for the antineoplastic activities of IMiDs, the exact mechanisms of action for IMiDs-based TME re-education remain largely unknown. This review presents an overview of IMiDs in regulation of immune cell function and their utilization in potentiating efficacy of immunotherapies across multiple types of B-cell neoplasms.

TNKS inhibitors potentiate proliferative inhibition of BET inhibitors via reducing β-Catenin in colorectal cancer cells

Colorectal cancer (CRC) is an aggressive malignancy with limited options for treatment. Targeting the bromodomain and extra terminal domain (BET) proteins by using BET inhibitors (BETis) could effectively interrupt the interaction with acetylated histones, inhibit genes transcription and have shown a certain effect on CRC inhibition. To improve the efficacy, the inhibitors of Tankyrases, which cause accumulation of AXIN through dePARsylation, in turn facilitate the degradation of β-Catenin and suppress the growth of adenomatous polyposis coli (APC)-mutated CRCs, were tested together with BETi as a combination treatment. We examined the effects of BETi and Tankyrases inhibitor (TNKSi) together on the proliferation, cell cycle and apoptosis of human CRCs cell lines with APC or CTNNB1 mutation, and elucidated the underlying molecular mechanisms affected by the double treatment. The result showed that the TNKSi could sensitize all tested CRC cell lines to BETi, and the synergistic effect was not only seen in cell proliferation inhibition, but also confirmed in decreased colony-forming ability and weaken EdU incorporation compared with monotherapy. Combined treatment resulted in enhanced G1 cell cycle arrest and increased apoptosis. In addition, we found β-Catenin was potentially inhibited by the combination and revealed that both BETi-induced transcriptional inhibition and TNKSi-mediated protein degradation all reduced the β-Catenin accumulation. In all, the synergistic effects suggest that combination of BETi and TNKSi could provide novel treatment opportunities for CRC, but both TNKSi and combination strategy need to be optimized.

Phase Ib trial of lenalidomide as post-remission therapy for older adults with acute myeloid leukemia: Safety and longitudinal assessment of geriatric functional domains

BACKGROUND AND OBJECTIVES

Novel, non-cytotoxic agents are driving a paradigm shift for treatment of older adults with acute myeloid leukemia (AML). Older patients who initially receive intensive cytotoxic induction may choose to not proceed with cytotoxic consolidation therapy. Lenalidomide is an orally-administered immunomodulatory small molecule with activity in AML and a favorable safety profile in older adults with active leukemia. We conducted a phase Ib study of lenalidomide as post-remission therapy in older adults and assessed its impact on geriatric functional domains.

MATERIALS AND METHODS

Participants were patients with AML over age 60 years who had undergone induction therapy and were poor candidates for cytotoxic consolidation. Lenalidomide was administered for 28 days in three dose cohorts. A Bayesian dose-escalation method determined cohort assignment and maximum tolerated dose (MTD). Geriatric assessment (GA) was performed before and after the cycle of lenalidomide.

RESULTS

Nineteen patients with median age 68 were treated with at least one 28-day course of lenalidomide. Dose-limiting toxicities were observed in three participants at 25 mg, zero participants at 35 mg, and one participant at 50 mg. MTD was 35 mg. Median relapse-free survival was 4.3 months. GA was completed before and after treatment in fifteen patients, demonstrating improved cognitive function and no changes in physical, psychological, or social function after lenalidomide.

CONCLUSION

Lenalidomide can be safely administered to older adults with AML with preservation of functional domains important to older patients. Serial GA can be performed in a novel drug study as a tool to characterize treatment tolerability.

Human leukocyte antigen (HLA) alleles as predictive factors for benefit from lenalidomide in acute myeloid leukemia (AML)

OBJECTIVES

Lenalidomide is an active agent in acute myeloid leukemia (AML); response rates are about 15-30%. There are no well-defined predictive factors for benefit from lenalidomide in AML. One of the mechanisms of lenalidomide is natural killer (NK) cell activation; hence human leukocyte antigen (HLA) class I alleles (serving as killer immunoglobulin-like receptor ligands) could play a predictive role. We here evaluate the same when lenalidomide was used as a bridge to transplant.

METHODS

Consecutive AML patients started on lenalidomide as bridge to transplant between Aug-2013 to Aug-2018 were included in this single centre retrospective analysis. The starting dose and schedule of lenalidomide were at the discretion of the treating clinician. Lenalidomide was scheduled to be stopped about 2-4 weeks prior to planned transplant admission (or was stopped earlier if there was intolerance). For this study, event was defined as progression/relapse while on lenalidomide or within 4 weeks of stopping the drug. The primary endpoint was event free survival (EFS). Those who underwent transplant without an event were censored on the day of transplant. Toxicities and post-transplant outcomes were secondary endpoints.

RESULTS

Twelve patients (8 males, median age 29 years) were included. At start of lenalidomide, 7 had complete remission (CR)-1 (measurable residual disease or MRD by flow cytometry was positive in 3, negative in 3, and 1 unknown), 4 CR-2 (all MRD negative) and 1 active disease. In the whole cohort, median EFS was not reached with projected 3 year EFS being 80%. There was a significantly reduced risk of event with HLA A*24 (0% vs 75%, P=0.018) or with HLA B*40 (0% vs 60%, P=0.045). Only 1 patient needed discontinuation due to toxicities (cytopenias). Among patients who underwent transplant, grade II-IV acute graft versus host disease (GVHD) was seen in 83%.

CONCLUSIONS

This is first study to show that HLA alleles may have a bearing on the effect of lenalidomide in AML and could serve as predictive biomarkers. These findings need to be confirmed in larger prospective studies.

Would the Recommended Dose Have Been Different Using Novel Dose-Finding Designs? Comparing Dose-Finding Designs in Published Trials

Simulation studies have shown that novel designs such as the continual reassessment method and the Bayesian optimal interval (BOIN) design outperform the 3 + 3 design by recommending the maximum tolerated dose (MTD) more often, using less patients, and allotting more patients to the MTD. However, it is not clear whether these novel designs would have yielded different results in the context of real-world dose-finding trials. This is a commonly mentioned reason for the continuous use of 3 + 3 designs for oncology trials, with investigators considering simulation studies not sufficiently convincing to warrant the additional design complexity of novel designs.

METHODS

We randomly sampled 60 published dose-finding trials to obtain 22 that used the 3 + 3 design, identified an MTD, published toxicity data, and had more than two dose levels. We compared the published MTD with the estimated MTD using the continual reassessment method and BOIN using target toxicity rates of 25% and 30% and toxicity data from the trial. Moreover, we compared patient allocation and sample size assuming that these novel designs had been implemented.

RESULTS

Model-based designs chose dose levels higher than the published MTD in about 40% of the trials, with estimated and observed toxicity rates closer to the target toxicity rates of 25% and 30%. They also assigned less patients to suboptimal doses and permitted faster dose escalation.

CONCLUSION

This study using published dose-finding trials shows that novel designs would recommend different MTDs and confirms the advantages of these designs compared with the 3 + 3 design, which were demonstrated by simulation studies.

Addition of lenalidomide to intensive treatment in younger and middle-aged adults with newly diagnosed AML: the HOVON-SAKK-132 trial

Lenalidomide, an antineoplastic and immunomodulatory drug, has therapeutic activity in acute myeloid leukemia (AML), but definitive studies about its therapeutic utility have been lacking. In a phase 3 study, we compared 2 induction regimens in newly diagnosed patients age 18 to 65 years with AML: idarubicine-cytarabine (cycle 1) and daunorubicin and intermediate-dose cytarabine (cycle 2) without or with lenalidomide (15 mg orally on days 1-21). One final consolidation cycle of chemotherapy or autologous stem cell transplantation (auto-SCT) or allogeneic SCT (allo-SCT) was provided according to a prognostic risk and minimal residual disease (MRD)-adapted approach. Event-free survival (EFS; primary end point) and other clinical end points were assessed. A second random assignment in patients in complete response or in complete response with incomplete hematologic recovery after cycle 3 or auto-SCT involved 6 cycles of maintenance with lenalidomide (10 mg on days 1-21) or observation. In all, 392 patients were randomly assigned to the control group, and 388 patients were randomly assigned to lenalidomide induction. At a median follow-up of 41 months, the study revealed no differences in outcome between the treatments (EFS, 44% ± 2% standard error and overall survival, 54% ± 2% at 4 years for both arms) although in an exploratory post hoc analysis, a lenalidomide benefit was suggested in SRSF2-mutant AML. In relation to the previous Dutch-Belgian Hemato-Oncology Cooperative Group and Swiss Group for Clinical Cancer Research (HOVON-SAKK) studies that used a similar 3-cycle regimen but did not pursue an MRD-guided approach, these survival estimates compare markedly more favorably. MRD status after cycle 2 lost prognostic value in intermediate-risk AML in the risk-adjusted treatment context. Maintenance with lenalidomide showed no apparent effect on relapse probability in 88 patients randomly assigned for this part of the study.

A phase I study of lenalidomide plus chemotherapy with idarubicin and cytarabine in patients with relapsed or refractory acute myeloid leukemia and high-risk myelodysplastic syndrome

Patients with relapsed/refractory (R/R) acute myeloid leukemia (AML) have poor outcomes and hematopoietic cell transplantation (HCT) is the only curative treatment. New targeted therapies improved survival in select patients with specific mutations, however management of patients without these molecular alterations is an unmet need. We conducted a phase one study of lenalidomide in combination with cytarabine/idarubicin salvage chemotherapy in patients with R/R AML and high‐risk myelodysplastic syndromes. A total of 33 patients were enrolled in the study (30 AML, 3 MDS), and treated at three dose levels with 3 + 3 design. Dose‐limiting toxicity (DLT) was seen in eight patients, including four hematologic DLTs. The most commonly observed non‐hematologic serious adverse events were febrile neutropenia, rash, sepsis and renal injury. Dose level −1, consisting of 25 mg/d lenalidomide D1‐21, 1 g/m² cytarabine D5‐8, and 8 mg/m² idarubicin D5‐7 was determined to be the maximum tolerated dose. Note, 15/33 (45%) of patients were able to receive pre‐planned 21 days of lenalidomide. Overall, 18 patients achieved complete remission (CR) (n = 14) or CR with incomplete count recovery (CRi) (n = 4) with total CR/CRi rate of 56%. The 1‐year and 2‐year overall survival (OS) were 24% and 10%, respectively. Among responders, 10/18 underwent allogeneic HCT and had a 1‐year OS of 40%. There was no molecular pattern associated with response. These data demonstrate that the combination had clinical activity in R/R AML. This regimen should be further investigated for patients who relapsed after HCT, and as a bridge therapy to HCT. (ClinicalTrials.gov identifier: NCT01132586).

Immunomodulatory Drugs in Acute Myeloid Leukemia Treatment

Immunomodulatory drugs (IMiDs) are analogs of thalidomide. They have immunomodulatory, antiangiogenic and proapoptotic properties and exert a role in regulating the tumor microenvironment. Recently IMiDs have been investigated for their pleiotropic properties and their therapeutic applications in both solid tumors (melanoma, prostate carcinoma and differentiated thyroid cancer) and hematological malignancies. Nowadays, they are applied in de novo and relapsed/refractory multiple myeloma, in myelodysplastic syndrome, in del5q syndrome with specific use of lenalidomide and B-cell lymphoma. Several studies have been conducted in the last few years to explore IMiDs possible use in acute myeloid leukemia treatment. Here we report the mechanisms of action of IMiDs in acute myeloid leukemia and their potential future therapeutic application in this disease.

Maintenance therapy in AML: The past, the present and the future

Curative treatment in acute myeloid leukemia (AML) depends on successful induction therapy to achieve a complete remission (CR), and subsequent post-remission therapy to prevent relapse. High relapse rates after consolidation therapy and after allogeneic stem cell transplant contribute to suboptimal outcomes in AML patients, and continue to represent a difficult challenge. Effective maintenance therapy could play an important role in prolonging the remission interval in the post-consolidation setting, especially in high risk AML patients. Maintenance treatment approaches based on conventional chemotherapy, immunotherapy, hypomethylating agents, and targeted small molecules have been explored in this setting, but no data so far have been convincing enough to establish this approach as the standard of care. However, ongoing and future studies including novel targeted therapies may demonstrate promising efficacy that could facilitate incorporation of maintenance therapy into clinical practice. In this review we summarize previous and ongoing approaches of maintenance therapy in AML and discuss the most promising strategies.

A systematic review and metaanalysis of the efficacy and adverse events of azacitidinepluslenalidomide treatment for patients with acute myeloid leukemia, myelodysplastic syndromes and chronic myelomonocytic leukemia 1

OBJECTIVES

The addition of lenalidomide (LEN) to azacitidine (AZA) may further improve the outcomes of acute myeloid leukemia (AML) patients as well as patients with high-risk myelodysplastic syndrome (MDS) and chronic myelomonocytic leukemia (CMML) patients although the evidence for this combination treatment is still relatively limited. This meta-analysis aimed to evaluate efficacy and adverse effects of AZA plus LEN for the treatment of patients with high-risk MDS, AML or CMML.

METHODS

The current study systematically identified all cohort studies of patients with AML and/or MDS and/or CMML who received AZA in combination with LEN that reported the overall complete remission (CR) rate and/or overall response rate (ORR). A DerSimonian-d random-effects model with double arcsine transformation was used for the pooled rates and 95% confidence interval (CI) of the all outcomes.

RESULTS

A total of 10 studies with 406 patients were identified and included into the meta-analysis. The pooled CR rate after the treatment with AZA-plus-LEN regimen was 33.0% (95% CI, 27.7%-38.7%, I² = 18%) while the pooled ORR was 49.9% (95% CI, 38.4%-61.5%, I² = 72%). Nonetheless, adverse events including grade 3-4 neutrophil toxicity events, platelet toxicity events and febrile neutropenia were common with AZA-plus-LEN regimen.

CONCLUSIONS

The current study may serve as a preliminary data to suggest that the addition of LEN may offer incremental benefit to patients with high-risk MDS, AML and CMML. However, randomized-controlled studies that directly compare the efficacy and adverse events of AZA-plus-LEN regimen versus AZA monotherapy are still needed.

Characteristics and outcomes of therapy-related myeloid neoplasms after peptide receptor radionuclide/chemoradionuclide therapy (PRRT/PRCRT) for metastatic neuroendocrine neoplasia: a single-institution series

PURPOSE

Peptide receptor radionuclide/chemoradionuclide therapy (PRRT/PRCRT) is an effective therapy for metastatic neuroendocrine neoplasia (NEN), but therapy-related myeloid neoplasms (t-MN) remain of concern. The study reviewed the clinicopathological features and outcomes of patients who developed t-MN.

METHODS

Retrospective analysis of all patients diagnosed with t-MN by 2016 WHO classification, from a cohort of 521 patients who received PRRT/PRCRT over a 12-year period. Molecular next-generation sequencing using an in-house 26-gene panel was performed.

RESULTS

Twenty-five of 521 (4.8%) patients were diagnosed with t-MN, including six acute myeloid leukaemia (AML) and 19 myelodysplastic syndrome (MDS). The median time from first cycle PRRT/PRCRT to diagnosis of t-MN was 26 months (range 4-91). Twenty-two of 25 (88%) patients had grade 1-2 pancreatic or small bowel NEN with moderate metastatic liver burden. Six patients (24%) had prior chemotherapy. Median number of PRRT cycles = 5 (22/25 (88%) with concomitant radiosensitising chemotherapy). All 25 patients achieved disease stabilisation (68%) or partial response (32%) on RECIST 1.1 at 3 months post-PRRT. At t-MN diagnosis, all patients presented with thrombocytopenia (median nadir 33 × 10⁹/L, range 3-75) and 17 (68%) remained NEN progression-free. Marrow genetic analysis revealed unfavourable karyotype in 16/25 (66%) patients with tumour protein 53 (TP53) mutation in nine (36%). Azacitidine therapy was utilised in ten eligible patients, while four received induction chemotherapy for AML. The median overall survival from first PRRT was 62 months (19-94), but from t-MN diagnosis was only 13 months (1-56), with death due primarily to haematological disease progression.

CONCLUSIONS

The diagnosis of t-MN after PRRT/PRCRT is an infrequent but serious complication with poor overall survival. Most patients present with thrombocytopenia; unfavourable genetic mutations have a poor response to t-MN treatment. Prospective data are needed to explore potential pre-existing genetic factors and predictive biomarkers to minimise the risk of t-MN.

Sequential azacitidine and lenalidomide for patients with relapsed and refractory acute myeloid leukemia: Clinical results and predictive modeling using computational analysis

BACKGROUND

Patients with relapsed and refractory (R/R) acute myeloid leukemia (AML) have limited treatment options. Genomically-defined personalized therapies are only applicable for a minority of patients. Therapies without identifiable targets can be effective but patient selection is challenging. The sequential combination of azacitidine with high-dose lenalidomide has shown activity; we aimed to determine the efficacy of this genomically-agnostic regimen in patients with R/R AML, with the intention of applying sophisticated methods to predict responders.

METHODS

Thirty-seven R/R AML/myelodysplastic syndrome patients were enrolled in a phase 2 study of azacitidine with lenalidomide. The primary endpoint was complete remission (CR) and CR with incomplete blood count recovery (CRi) rate. A computational biological modeling (CBM) approach was applied retrospectively to predict outcomes based on the understood mechanisms of azacitidine and lenalidomide in the setting of each patients' disease.

FINDINGS

Four of 37 patients (11%) had a CR/CRi; the study failed to meet the alternative hypothesis. Significant toxicity was observed in some cases, with three treatment-related deaths and a 30-day mortality rate of 14%. However, the CBM method predicted responses in 83% of evaluable patients, with a positive and negative predictive value of 80% and 89%, respectively.

INTERPRETATION

Sequential azacitidine and high-dose lenalidomide is effective in a minority of R/R AML patients; it may be possible to predict responders at the time of diagnosis using a CBM approach. More efforts to predict responses in non-targeted therapies should be made, to spare toxicity in patients unlikely to respond and maximize treatments for those with limited options.

FLT3 inhibitor design using molecular docking based virtual screening for acute myeloid leukemia

Acute Myeloid Leukaemia (AML) is a blood cancer, which affects the red blood cells in the bone marrow. Of the possible proteins that are affected in AML, fms-like tyrosine kinase 3 (FLT3) has long been recognized as a potential therapeutic target as it affects the other signaling pathways and leads to a cascade of events. First-generation inhibitors sorafenib and midostaurin, as well as secondgeneration agents such as quizartinib and crenolanib are known. It is of interest to identify new compounds against FLT3 with improved activity using molecular docking and virtual screening. Molecular docking of existing inhibitors selected a top scoring bestestablished candidate Quizartinib having PubChem CID: 24889392. Similarity searching resulted in compound XGIQBUNWFCCMASUHFFFAOYSA-NPubChemCID: 44598530 which shows higher affinity scores. A comparative study of both the compounds using a drug-drug comparison, ADMET studies, boiled egg plot and pharmacophore parameters and properties confirmed the result and predicted the ligand to be an efficient inhibitor of FLT3.

Treatment of Lymphoid and Myeloid Malignancies by Immunomodulatory Drugs

Thalidomide and its derivatives (lenalidomide, pomalidomide, avadomide, iberdomide hydrochoride, CC-885 and CC-90009) form the family of immunomodulatory drugs (IMiDs). Lenalidomide (CC5013, Revlimid®) was approved by the US FDA and the EMA for the treatment of multiple myeloma (MM) patients, low or intermediate-1 risk transfusion-dependent myelodysplastic syndrome (MDS) with chromosome 5q deletion [del(5q)] and relapsed and/or refractory mantle cell lymphoma following bortezomib. Lenalidomide has also been studied in clinical trials and has shown promising activity in chronic lymphocytic leukemia (CLL) and non-Hodgkin lymphoma (NHL). Lenalidomide has anti-inflammatory effects and inhibits angiogenesis. Pomalidomide (CC4047, Imnovid® [EU], Pomalyst® [USA]) was approved for advanced MM insensitive to bortezomib and lenalidomide. Other IMiDs are in phases 1 and 2 of clinical trials. Cereblon (CRBN) seems to have an important role in IMiDs action in both lymphoid and myeloid hematological malignancies. Cereblon acts as the substrate receptor of a cullin-4 really interesting new gene (RING) E3 ubiquitin ligase CRL4CRBN. This E3 ubiquitin ligase in the absence of lenalidomide ubiquitinates CRBN itself and the other components of CRL4CRBN complex. Presence of lenalidomide changes specificity of CRL4CRBN which ubiquitinates two transcription factors, IKZF1 (Ikaros) and IKZF3 (Aiolos), and casein kinase 1α (CK1α) and marks them for degradation in proteasomes. Both these transcription factors (IKZF1 and IKZF3) stimulate proliferation of MM cells and inhibit T cells. Low CRBN level was connected with insensitivity of MM cells to lenalidomide. Lenalidomide decreases expression of protein argonaute-2, which binds to cereblon. Argonaute-2 seems to be an important drug target against IMiDs resistance in MM cells. Lenalidomide decreases also basigin and monocarboxylate transporter 1 in MM cells. MM cells with low expression of Ikaros, Aiolos and basigin are more sensitive to lenalidomide treatment. The CK1α gene (CSNK1A1) is located on 5q32 in commonly deleted region (CDR) in del(5q) MDS. Inhibition of CK1α sensitizes del(5q) MDS cells to lenalidomide. CK1α mediates also survival of malignant plasma cells in MM. Though, inhibition of CK1α is a potential novel therapy not only in del(5q) MDS but also in MM. High level of full length CRBN mRNA in mononuclear cells of bone marrow and of peripheral blood seems to be necessary for successful therapy of del(5q) MDS with lenalidomide. While transfusion independence (TI) after lenalidomide treatment is more than 60% in MDS patients with del(5q), only 25% TI and substantially shorter duration of response with occurrence of neutropenia and thrombocytopenia were achieved in lower risk MDS patients with normal karyotype treated with lenalidomide. Shortage of the biomarkers for lenalidomide response in these MDS patients is the main problem up to now.

Efficacy and safety of lenalidomide for the treatment of acute myeloid leukemia: a systematic review and meta-analysis

Background

Lenalidomide is effective for the treatment of low-risk myelodysplastic syndromes with deletion 5q abnormalities. However, whether lenalidomide leads to a significant improvement in treatment response and overall survival (OS) in cases of acute myeloid leukemia (AML) remains controversial. A systematic review and a meta-analysis were performed to evaluate the efficacy and safety of lenalidomide in the treatment of AML.

Methods

Clinical studies were identified from the Cochrane Central Register of Controlled Trials, PubMed, Embase, and ClinicalTrials.gov. Efficacy outcomes included overall response rate (ORR), complete remission (CR), and OS. Safety was evaluated based on the incidence of grade 3 and 4 treatment-related adverse events (AEs).

Results

Eleven studies were included in our meta-analysis; collectively these studies featured 407 AML patients. Pooled estimates for overall ORR and CR were 31% (95% CI: 26%–36%) and 21% (95% CI: 16%–27%), respectively. Thrombocytopenia, anemia, neutropenia, and infection were the most common grade 3 and 4 AEs.

Conclusion

Lenalidomide may have some clinical activity in AML, but the population that would benefit from lenalidomide and incorporating lenalidomide into combination drug strategies need to be better defined.

Durable remission in a patient of mixed phenotype acute leukemia with Philadelphia chromosome-positive treated with nilotinib and lenalidomide: A case report

RATIONALE

Philadelphia chromosome-positive mixed phenotype acute leukemia (Ph+ MPAL) is a rare type of leukemia with poor prognosis. Tyrosine kinase inhibitors (TKIs) in combination with chemotherapy have significantly improved its remission rate. However, relapse remains the major obstacle to achieve long survival. Lenalidomide is a second-generation oral immunomodulatory drug that has been broadly applied in the treatment of various hematological malignancies.

PATIENT CONCERNS

A 54-year-old Chinese male patient who complained of chest pain and fatigue for 20 days. Bone marrow aspirate examination revealed hypercellularity with 70% blast cells. Flow cytometry analysis revealed that the blast cells exhibit both myeloid and lymphoid lineage antigens. Chromosomal analysis reveals t(9;22)(q34;q11) translocation. Minor BCR-ABL fusion gene was positive.

DIAGNOSIS

Philadelphia chromosome-positive mixed phenotype acute leukemia.

INTERVENTIONS

After relapsed from routine chemotherapy plus imatinib, the therapy was switched to oral therapy with nilotinib and lenalidomide due to his feeble condition.

OUTCOMES

He successfully achieved long survival after oral therapy with nilotinib and lenalidomide.

LESSONS

Combination of TKIs with lenalidomide may be an effective maintenance treatment regimen for Ph+ MPAL patients with minimal side effect.

A phase I study of lenalidomide plus chemotherapy with mitoxantrone, etoposide, and cytarabine for the reinduction of patients with acute myeloid leukemia

Patients with relapsed AML have a poor prognosis and limited responses to standard chemotherapy. Lenalidomide is an immunomodulatory drug that may modulate anti-tumor immunity. We performed a study to evaluate the safety and tolerability of lenalidomide with mitoxantrone, etoposide and cytarabine (MEC) in relapsed/refractory AML. Adult patients with relapsed/refractory AML were eligible for this phase I dose-escalation study. We enrolled 35 patients using a "3 + 3" design, with a 10 patient expansion cohort at the maximum tolerated dose (MTD). Lenalidomide was initially given days 1-14 and MEC days 4-8; due to delayed count recovery, the protocol was amended to administer lenalidomide days 1-10. The dose of lenalidomide was then escalated starting at 5 mg/d (5-10-25-50). The primary objective was tolerability and MTD determination, with secondary outcomes including overall survival (OS). The MTD of lenalidomide combined with MEC was 50 mg/d days 1-10. Among the 35 enrolled patients, 12 achieved complete remission (CR) (34%, 90%CI 21-50%); 30-day mortality was 6% and 60-day mortality 13%. The median OS for all patients was 11.5 months. Among 17 patients treated at the MTD, 7 attained CR (41%); the median OS was not reached while 12-month OS was 61%. Following therapy with MEC and lenalidomide, patient CD4+ and CD8+ T-cells demonstrated increased inflammatory responses to autologous tumor lysate. The combination of MEC and lenalidomide is tolerable with an RP2D of lenalidomide 50 mg/d days 1-10, yielding encouraging response rates. Further studies are planned to explore the potential immunomodulatory effect of lenalidomide and MEC.

Acute myeloid leukemia in the elderly: therapeutic options and choice

Acute myeloid leukemia (AML) therapies are rapidly evolving with novel targeted therapies showing high-level responses in a notoriously difficult to treat group of patients - the elderly and unfit. This review will examine the outcomes of older AML patients (>60 years old) with conventional induction strategies, and published literature on risks of pursuit of induction. Low-intensity combination therapy response rates appear to be approaching that of induction regimens, and with lower toxicity, low-intensity therapy likely represents the future standard approach in this age group. Lastly, allogeneic transplant appears to have a role in increasing durable remissions regardless of age and should be considered in patients with limited comorbidities.

Randomized study of continuous high-dose lenalidomide, sequential azacitidine and lenalidomide, or azacitidine in persons 65 years and over with newly-diagnosed acute myeloid leukemia

Therapy of acute myeloid leukemia in older persons is associated with poor outcomes because of intolerance to intensive therapy, resistant disease and co-morbidities. This multi-center, randomized, open-label, phase II trial compared safety and efficacy of three therapeutic strategies in patients 65 years or over with newly-diagnosed acute myeloid leukemia: 1) continuous high-dose lenalidomide (n=15); 2) sequential azacitidine and lenalidomide (n=39); and 3) azacitidine only (n=34). The efficacy end point was 1-year survival. Median age was 76 years (range 66–87 years). Thirteen subjects (15%) had prior myelodysplastic syndrome and 41 (47%) had adverse cytogenetics. One-year survival was 21% [95% confidence interval (CI): 0, 43%] with high-dose lenalidomide, 44% (95%CI: 28, 60%) with sequential azacitidine and lenalidomide, and 52% (95%CI: 35, 70%) with azacitidine only. Lenalidomide at a continuous high-dose schedule was poorly-tolerated resulting in a high rate of early therapy discontinuations. Hazard of death in the first four months was greatest in subjects receiving continuous high-dose lenalidomide; hazards of death thereafter were similar. These data do not favor use of continuous high-dose lenalidomide or sequential azacitidine and lenalidomide over the conventional dose and schedule of azacitidine only in patients aged 65 years or over with newly-diagnosed acute myeloid leukemia. (clinicaltrials.gov identifier: 01358734).

The management and treatment of acute leukemias in the elderly population

INTRODUCTION

Treatment of elderly patients with acute leukemia is challenging. Older age is associated with increased risk of treatment-related toxicity. Currently, no consensus exists regarding optimal therapy in this patient population. Areas covered: The following review is a comprehensive summary of various therapeutic options reported over the past few years in elderly patients with acute leukemia. Expert commentary: While evidences can guide identification of frail older patients, sensitive assessment strategies are required to identify fit and vulnerable patients regardless of chronologic age. Individualized treatments may take into account not only an increase in survival, but also the maintenance or improvement in terms of quality of life, the management of symptoms, and a maximization of time outside of hospital care. In this setting, comprehensive geriatric assessments have been shown to improve routine assessment. Molecular abnormalities provide the genomic footprint for the development of targeted therapies. The addition of new monoclonal antibodies to conventional treatments also demonstrated promising primary results. Ongoing clinical trials testing the activity of these new agents may reshape treatment strategies in the elderly patient population.

Low-dose lenalidomide plus cytarabine in very elderly, unfit acute myeloid leukemia patients: Final result of a phase II study

Outcome for elderly patients with acute myeloid leukemia (AML) is extremely poor. Intensive induction chemotherapy is often unsuitable. Sixty-six newly diagnosed AML patients (median age: 76years), ineligible for standard therapy, were consecutively treated with low-dose lenalidomide (10mg/day orally, days 1-21) plus 10mg/m² low-dose cytarabine, subcutaneously, twice a day (days 1-15) every six weeks, up to 6 cycles. Complete remission (CR) rate was 36.3% according to intention-to-treat. Responding patients had a longer median overall survival than non-responders (517 vs. 70days, P<0.001). The achievement of CR was not predicted by bone marrow blast count, cytogenetics, molecular markers, prior MDS, white blood cell count. Conversely, by studying the global gene expression profile, we identified a molecular signature, including 309 genes associated with clinical response (CR versus no CR). Based on the expression of a minimal set of 16 genes, we developed an algorithm to predict treatment response, that was successfully validated by showing an overall accuracy of 88%. We met the primary endpoint of the study, by beating the estimated successful CR rate (P1) fixed at 30%. Moreover, CR induced by this 2-drug combo was efficiently predicted by genetic profiling, identifying a biomarker that warrants validation in independent series.

Targeting the cancer epigenome: synergistic therapy with bromodomain inhibitors

Epigenetic and genomic alterations regulate the transcriptional landscape of cells during cancer onset and progression. Recent clinical studies targeting the epigenetic 'readers' (bromodomains) for cancer therapy have established the effectiveness of bromodomain (BRD) and extraterminal (BET) inhibitors in treating several types of cancer. In this review, we discuss key mechanisms of BET inhibition and synergistic combinations of BET inhibitors with histone deacetylase inhibitors (HDACi), histone methyltransferase inhibitors (HMTi), DNA methyltransferase inhibitors (DNMTi), kinase, B-cell lymphoma 2 (Bcl-2) and proteosome inhibitors, and immunomodulatory drugs for cancer therapy. We also highlight the potential of such combinations to overcome drug resistance, and the evolving approaches to developing novel BET inhibitors.

Treatment of Elderly Patients With Acute Myeloid Leukemia

OPINION STATEMENT

There is no standard of care for older patients with acute myeloid leukemia (AML) unfit for intensive chemotherapy. AML in older patients remains an area of significant unmet need necessitating novel therapeutic strategies. In older patients with normal cytogenetics, molecular variables can be helpful in refining risk. This molecular revolution has promoted a shift in the treatment paradigm of AML. Open new questions concern the necessity of an individualized therapy that may take into account not only an increase in survival but also the maintenance or improvement in terms of quality of life, the management of symptoms, and a maximization of time outside of hospital care. Molecular abnormalities provide the genomic footprint for the development of targeted therapies. Clinical trials testing the activity of these new agents are ongoing and may reshape treatment strategies for these patients. One promising strategy is to combine low-intensity treatments with novel agents.

Azacitidine in adult patients with acute myeloid leukemia

Azacitidine is recommended front-line treatment for older patients with acute myeloid leukemia (AML) who are not candidates for intensive treatment regimens, and was recently granted approval in the European Union for treatment of adult AML. Reviewed here is azacitidine experience in AML, including: mechanistic and pharmacokinetic data; safety and efficacy in controlled trials; treatment effects in AML subpopulations defined by disease characteristics; experience in unselected patients treated in the community setting; clinical outcomes relative to other approved AML therapies; and experience with azacitidine-based combination treatment regimens. Collectively, these data suggest that (a) azacitidine may prolong overall survival to a similar or greater extent than do other approved AML treatments, but with less toxicity, (b) azacitidine may be the preferred treatment option for older patients with unfavorable cytogenetics, and (c) experience and outcomes with azacitidine in the clinic are similar to those seen in clinical trials. Continued investigation of combination regimens on an azacitidine backbone is warranted.

Azacitidine front-line in 339 patients with myelodysplastic syndromes and acute myeloid leukaemia: comparison of French-American-British and World Health Organization classifications

BACKGROUND

The MDS-IWG and NCCN currently endorse both FAB and WHO classifications of MDS and AML, thus allowing patients with 20-30 % bone marrow blasts (AML20-30, formerly MDS-RAEB-t) to be categorised and treated as either MDS or AML. In addition, an artificial distinction between AML20-30 and AML30+ was made by regulatory agencies by initially restricting approval of azacitidine to AML20-30. Thus, uncertainty prevails regarding the diagnosis, prognosis and optimal treatment timing and strategy for patients with AML20-30. Here, we aim to provide clarification for patients treated with azacitidine front-line.

METHODS

The Austrian Azacitidine Registry is a multicentre database (ClinicalTrials.gov: NCT01595295). For this analysis, we selected 339 patients treated with azacitidine front-line. According to the WHO classification 53, 96 and 190 patients had MDS-RAEB-I, MDS-RAEB-II and AML (AML20-30: n = 79; AML30+: n = 111), respectively. According to the FAB classification, 131, 101 and 111 patients had MDS-RAEB, MDS-RAEB-t and AML, respectively.

RESULTS

The median ages of patients with MDS and AML were 72 (range 37-87) and 77 (range 23-93) years, respectively. Overall, 80 % of classifiable patients (≤30 % bone marrow blasts) had intermediate-2 or high-risk IPSS scores. Most other baseline, treatment and response characteristics were similar between patients diagnosed with MDS or AML. WHO-classified patients with AML20-30 had significantly worse OS than patients with MDS-RAEB-II (13.1 vs 18.9 months; p = 0.010), but similar OS to patients with AML30+ (10.9 vs 13.1 months; p = 0.238). AML patients that showed MDS-related features did not have worse outcomes compared with patients who did not (13.2 vs 8.9 months; p = 0.104). FAB-classified patients with MDS-RAEB-t had similar survival to patients with AML30+ (12.8 vs 10.9 months; p = 0.376), but significantly worse OS than patients with MDS-RAEB (10.9 vs 24.4 months; p < 0.001).

CONCLUSIONS

Our data demonstrate the validity of the WHO classification of MDS and AML, and its superiority over the former FAB classification, for patients treated with azacitidine front-line. Neither bone marrow blast count nor presence of MDS-related features had an adverse prognostic impact on survival. Patients with AML20-30 should therefore be regarded as having 'true AML' and in our opinion treatment should be initiated without delay.

The safety of treatment options for elderly people with acute myeloid leukemia

INTRODUCTION

Life expectancy in elderly patients with acute myeloid leukemia (AML) is a function of age, disability, and co-morbidity, combined with leukemia characteristics. There is currently no consensus regarding the optimal therapeutic strategy for older adults with AML. Although selected older adults with AML can benefit from intensive therapies, recent evidence supports the use of lower-intensity therapies in most patients and emphasizes the importance of tolerability and quality of life.

AREAS COVERED

Results of the current clinical trials and safety data are reviewed.

EXPERT OPINION

Treatment recommendations for elderly patients with AML need to be individualized. In order to avoid toxicities, hematologists should collaborate more with geriatricians to identify clues of vulnerability in elderly patients through the study of functional physical, physiological, cognitive, social, and psychological parameters.

Low Dose Cytosine Arabinoside and Azacitidine Combination in Elderly Patients with Acute Myeloid Leukemia and Refractory Anemia with Excess Blasts (MDS-RAEB2)

Only one-third of elderly (>60 years) AML and MDS-RAEB2 patients may receive intensive chemotherapy treatment alternatives that are limited in this patient group due to the potential of severe toxicity. Previous studies have shown that azacitidine and low dose cytarabine treatments may be a beneficial treatment option for these patients. In this study, we aimed to good results with low toxicity in elderly patients. We retrospectively analyzed the AML and MDS-RAEB2 patients who received azacitidine monotherapy and azacitidine and LDL-ara-c combination therapy for a comparison of their response to therapy, survival rates, and toxicity rates and for determining the factors that could affect their overall survival. A total of 27 patients who were diagnosed with de novo AML and MDS-RAEB2 and who received at least four cycles of chemotherapy were included in the study, and the data were evaluated retrospectively. When monotherapy and combination therapy groups were compared, the pretreatment bone marrow blast count was observed to be greater in the combination therapy group. A statistically significant difference was not detected between the groups regarding the response to therapy ratios (p = 0.161) (42.9 and 57.1 %, respectively). No difference was detected between the groups regarding therapy-related toxicity. Infections were the most common complication. Progression-free survival was 30.3 % for the azacitidine monotherapy group and 66.7 % for the combination (azacitidine + LD-ara-c) group. The factors influencing the overall survival rate were determined based on the response to the first-line therapies, more than a grade 2 infection, fever, and relapse in a multi-variance analysis. The combination therapy may be a well-tolerated treatment option for the elderly, vulnerable AML patients whose blast count is high in response to therapy rates, overall survival rates, and toxicities are not different, although the pre-treatment bone marrow blast count was greater in the combination therapy groups compared with the monotherapy group.

Novel immunotherapeutic approaches for the treatment of acute leukemia (myeloid and lymphoblastic)

There have been major advances in our understanding of the multiple interactions between malignant cells and the innate and adaptive immune system. While the attention of immunologists has hitherto focused on solid tumors, the specific immunobiology of acute leukemias is now becoming defined. These discoveries have pointed the way to immune interventions building on the established graft-versus-leukemia (GVL) effect from hematopoietic stem-cell transplant (HSCT) and extending immunotherapy beyond HSCT to individuals with acute leukemia with a diversity of immune manipulations early in the course of the leukemia. At present, clinical results are in their infancy. In the coming years larger studies will better define the place of immunotherapy in the management of acute leukemias and lead to treatment approaches that combine conventional chemotherapy, immunotherapy and HSCT to achieve durable cures.

Are we curing more older adults with acute myeloid leukemia with allogeneic transplantation in CR1?

PURPOSE OF REVIEW

Despite the fact that acute myeloid leukemia (AML) is most common in older adults aged at least 60 years, curative therapy remains elusive in this population. Here we examine the data for predicting which patients are candidates for 'curative therapy', available therapeutic options, and the utilization of reduced intensity allogeneic stem cell transplantation in first remission.

RECENT FINDINGS

Incorporation of geriatric assessment tools to assess patient frailty, in addition to evaluation of comorbid conditions, improves patient selection for intense therapy. The majority of patients eligible for and treated with induction chemotherapy achieve complete remission, and overall survival in the older AML population is superior after allogeneic stem cell transplant. However, population-based studies continue to demonstrate the undertreatment or lack of treatment of older AML patients.

SUMMARY

New patient assessment tools, ability to offer more successful outcomes after induction chemotherapy, and improved survival after allogeneic transplantation has not yet translated to increased 'curative' treatment on a population level of older AML patients. It is critical that the tools and therapies available be put into practice while older patient enrollment in well designed therapeutic clinical trials which include the option of allogeneic transplantation is increased.

Hypomethylation of TET2 Target Genes Identifies a Curable Subset of Acute Myeloid Leukemia

BACKGROUND

Acute myeloid leukemia (AML) is curable in a subset of cases. The DNA methylation regulator TET2 is frequently mutated in AML, and we hypothesized that studying TET2-specific differentially methylated CpGs (tet2-DMCs) improves AML classification.

METHODS

We used bisulfite pyrosequencing to analyze the methylation status of four tet2-DMCs (SP140, MCCC1, EHMT1, and MTSS1) in a test group of 94 consecutive patients and a validation group of 92 consecutive patients treated with cytarabine-based chemotherapy. Data were analyzed with hierarchical clustering, Cox proportional hazards regression, and Kaplan-Meier analyses. All statistical tests were two-sided.

RESULTS

In the test cohort, hierarchical clustering analysis identified low levels of tet2-DMC methylation in 31 of 94 (33%) cases, and these had markedly longer overall survival (median survival 72+ vs 14 months, P = .002). Similar results were seen in the validation cohort. tet2-DMC-low status was shown to be an independent predictor of overall survival (hazard ratio = 0.29, P = .0002). In The Cancer Genome Atlas (TCGA) dataset where DNA methylation was analyzed by a different platform, tet2-DMC-low methylation was also associated with improved outcome (median survival = 55 vs 15 months, P = .0003) and was a better predictor of survival than mutations in TET2, IDH1, or IDH2, individually or combined.

CONCLUSIONS

Low levels of tet2-DMC methylation define a subgroup of AML that is highly curable and cannot be identified solely by genetic and cytogenetic analyses.

Sequential azacitidine plus lenalidomide in previously treated elderly patients with acute myeloid leukemia and higher risk myelodysplastic syndrome

The outcome of sequential azacitidine with lenalidomide has not been reported in previously treated patients with acute myeloid leukemia (AML) and higher risk myelodysplastic syndrome (MDS). This study describes a phase 2 study evaluating the safety and efficacy of this combination in elderly patients with AML and MDS with prior hypomethylating agent (HMA) and/or immunomodulatory agent exposure. Patients were treated on a 42-day cycle with azacitidine at 75 mg/m2 SQ/IV daily on days 1-7, followed by lenalidomide 50 mg orally daily on days 8-28. The median number of treatment cycles on study was two (range = 1-11). Of 32 evaluable patients, the overall response rate was 25%. Neutropenic fever was the most common serious adverse event, but overall the combination was well-tolerated. The median overall survival (OS) for responders vs non-responders was 9.8 vs 4.0 months, respectively (HR = 0.36, p = 0.016). In conclusion, this combination demonstrated modest clinical activity in this poor risk population.

Acute Myeloid Leukemia in the Elderly Patient: New Strategies

Although selected older adults with acute myeloid leukemia can benefit from intensive therapies, recent evidences support the use of lower-intensity therapies (hypomethylating agents or low-dose cytarabine) in most of these patients and emphasize the importance of tolerability and quality of life. Individualized approaches to treatment decision-making beyond consideration of chronologic age alone should therefore be considered. One promising strategy is to combine low-intensity treatments with novel agents.

International phase 3 study of azacitidine vs conventional care regimens in older patients with newly diagnosed AML with >30% blasts

This multicenter, randomized, open-label, phase 3 trial evaluated azacitidine efficacy and safety vs conventional care regimens (CCRs) in 488 patients age ≥65 years with newly diagnosed acute myeloid leukemia (AML) with >30% bone marrow blasts. Before randomization, a CCR (standard induction chemotherapy, low-dose ara-c, or supportive care only) was preselected for each patient. Patients then were assigned 1:1 to azacitidine (n = 241) or CCR (n = 247). Patients assigned to CCR received their preselected treatment. Median overall survival (OS) was increased with azacitidine vs CCR: 10.4 months (95% confidence interval [CI], 8.0-12.7 months) vs 6.5 months (95% CI, 5.0-8.6 months), respectively (hazard ratio [HR] was 0.85; 95% CI, 0.69-1.03; stratified log-rank P = .1009). One-year survival rates with azacitidine and CCR were 46.5% and 34.2%, respectively (difference, 12.3%; 95% CI, 3.5%-21.0%). A prespecified analysis censoring patients who received AML treatment after discontinuing study drug showed median OS with azacitidine vs CCR was 12.1 months (95% CI, 9.2-14.2 months) vs 6.9 months (95% CI, 5.1-9.6 months; HR, 0.76; 95% CI, 0.60-0.96; stratified log-rank P = .0190). Univariate analysis showed favorable trends for azacitidine compared with CCR across all subgroups defined by baseline demographic and disease features. Adverse events were consistent with the well-established safety profile of azacitidine. Azacitidine may be an important treatment option for this difficult-to-treat AML population. This trial was registered at www.clinicaltrials.gov as #NCT01074047.

Expanding role of lenalidomide in hematologic malignancies

Lenalidomide is an immunomodulatory agent that has been approved by the US Food and Drug Administration for treatment of multiple myeloma, deletion 5q myelodysplastic syndrome, and mantle cell lymphoma. In addition, it has clinical activity in lymphoproliferative disorders and acute myeloid leukemia. The mode of action includes immunomodulatory, anti-inflammatory, antiangiogenic, and antiproliferative mechanisms. The antitumor effect is a result of direct interference of key pathways in tumor cells and indirect modulation of the tumor microenvironment. There has been no recent collective review on lenalidomide in multiple myeloma, myelodysplastic syndrome/acute myeloid leukemia, and lymphoma. This review summarizes the results of current clinical studies of lenalidomide, alone and in combination with other agents, as a therapeutic option for various hematologic malignancies.

Azacitidine and lenalidomide as an alternative treatment for refractory acute myeloid leukemia: a case report

CONTEXT

Refractory acute myeloid leukemia (AML) is a difficult disease to control with second or third-line chemotherapy regimens. In this report, we describe using azacitidine in combination with lenalidomide as salvage therapy.

CASE REPORT

52-year-old female was diagnosed with refractory AML and high-risk cytogenetics: complex monosomal karyotype consisting of t (3, 3) in association with monosomy 7 and del 5q. Morphological remission associated with maintenance of the cytogenetic abnormality of chromosome 3 and disappearance of the abnormalities relating to chromosomes 5 and 7 was achieved after three cycles of combination therapy with azacitidine and lenalidomide.

CONCLUSION

Azacitidine plus lenalidomide can be a therapeutic option for patients with refractory AML, as illustrated in this case.

Sequential azacitidine and lenalidomide in patients with high-risk myelodysplastic syndromes and acute myeloid leukaemia: a single-arm, phase 1/2 study

BACKGROUND

The standard of care for myelodysplastic syndromes is hypomethylating agents such as azacitidine. However, responses to azacitidine are generally temporary, and outcomes after hypomethylating agent failure are dismal. Therefore, the development of more effective treatments is crucial to improve outcomes in patients with myelodysplastic syndromes. We aimed to assess azacitidine and lenalidomide in patients with high-risk myelodysplastic syndromes and acute myeloid leukaemia.

METHODS

We did this single-arm phase 1/2 study at the University of Texas MD Anderson Cancer Center, TX, USA. Patients of any age were eligible for phase 1 and 2a if they had relapsed or refractory acute myeloid leukaemia or myelodysplastic syndrome with bone marrow blasts more than 10%. For phase 2b, eligible participants were previously untreated with myelodysplastic syndrome with an International Prognostic Scoring System (IPSS) score of intermediate-1 or higher with up to 30% blasts. All participants received 75 mg/m(2) azacitidine once a day for days 1-5 for each 28 day cycle. We gave patients oral lenalidomide for 5 or 10 days starting on day 6. We assessed seven lenalidomide doses in a 3 + 3 phase 1 design (n=28). The primary endpoint in phase 1 was the maximum tolerated dose, and the primary endpoint in phase 2 was overall survival. Outcome analyses were by intention to treat. This study is registered with ClinicalTrials.gov, number NCT01038635.

FINDINGS

Between Dec 30, 2009, and June, 17, 2013, we enrolled 88 patients (28 in phase 1 and 60 in phase 2). One patient unexpectedly died in the phase 1 study at the highest dose level, six more patients were recruited with no further serious adverse events. We recorded no dose-limiting toxic effects, and the maximum tolerated dose of lenalidomide in combination with azacitidine in patients with acute myeloid leukaemia and myelodysplastic syndrome was initially established at 50 mg per day for 10 days. In the first 20 patients in phase 2, we noted a high rate of myelosuppression and myelosuppression-related toxic effects; therefore, we amended the lenalidomide dose to 25 mg per day for 5 days. We also adjusted the inclusion criteria to include patients with less than 30% blasts to focus mainly on patients with myelodysplastic syndromes. Median overall survival was 75 weeks (IQR 25-not reached) for the 40 patients in phase 2b. The most common grade 3-4 adverse events overall were neutropenic fever (n=27) and pneumonia (n=18).

INTERPRETATION

We have identified a safe and active sequential treatment combination of azacitidine and lenalidomide for patient with myelodysplastic syndrome and have preliminary evidence that this dose is also safe for patients with acute myeloid leukaemia.

FUNDING

MD Anderson Cancer Center and Celgene.

Finding the optimal combination therapy for the treatment of newly diagnosed AML in older patients unfit for intensive therapy

There is no standard of care for older patients with newly diagnosed acute myeloid leukemia (AML) unfit for intensive therapy, and prognosis with currently recommended low-intensity therapies (decitabine, azacitidine, and low-dose cytarabine [LDAC]) remains poor. One promising strategy is to combine low-intensity treatments with novel agents. Gemtuzumab ozogamicin, tipifarnib, and barasertib have been investigated in phase 2/3 or 3 trials combined with LDAC, and phase 3 trials are currently investigating sapacitabine plus decitabine, and volasertib plus LDAC in AML. This review discusses current treatment recommendations and the development of combination therapies for older patients unfit for intensive therapy.

Alternative novel therapies for the treatment of elderly acute myeloid leukemia patients

With a median age at diagnosis of approximately 65-70 years, acute myeloid leukemia (AML) represents a major therapeutic challenge in the elderly. Only 30-35% of elderly patients with AML are considered eligible for intensive chemotherapy and do actually receive it. However, the long-term benefit associated with intensive chemotherapy remains marginal, and the overall outcome for this population remains poor. The remaining 60-65% of elderly AML patients receives supportive care only. Nevertheless, several studies have indicated that patients who receive any therapy had a better outcome if compared with patients who receive supportive care only. Thus, the development of novel, less toxic, targeted agents is offering new options to older AML patients who are unfit for intensive approaches. In the present review, we will report on the results achieved using intensive chemotherapy and novel agents, and will describe some of the new strategies under development for treating older AML patients.