Preclinical pharmacokinetic/pharmacodynamic/efficacy relationships for alisertib, an investigational small-molecule inhibitor of Aurora A kinase

Synergy of EGFR and AURKA Inhibitors in KRAS-mutated Non-small Cell Lung Cancers

The most common oncogenic driver mutations for non-small cell lung cancer (NSCLC) activate EGFR or KRAS. Clinical trials exploring treatments for EGFR- or KRAS-mutated (EGFRmut or KRASmut) cancers have focused on small-molecule inhibitors targeting the driver mutations. Typically, these inhibitors perform more effectively based on combination with either chemotherapies, or other targeted therapies. For EGFRmut NSCLC, a combination of inhibitors of EGFR and Aurora-A kinase (AURKA), an oncogene commonly overexpressed in solid tumors, has shown promising activity in clinical trials. Interestingly, a number of recent studies have indicated that EGFR activity supports overall viability of tumors lacking EGFR mutations, and AURKA expression is abundant in KRASmut cell lines. In this study, we have evaluated dual inhibition of EGFR and AURKA in KRASmut NSCLC models. These data demonstrate synergy between the EGFR inhibitor erlotinib and the AURKA inhibitor alisertib in reducing cell viability and clonogenic capacity in vitro, associated with reduced activity of EGFR pathway effectors, accumulation of enhanced aneuploid cell populations, and elevated cell death. Importantly, the erlotinib-alisertib combination also synergistically reduces xenograft growth in vivo. Analysis of signaling pathways demonstrated that the combination of erlotinib and alisertib was more effective than single-agent treatments at reducing activity of EGFR and pathway effectors following either brief or extended administration of the drugs. In sum, this study indicates value of inhibiting EGFR in KRASmut NSCLC, and suggests the specific value of dual inhibition of AURKA and EGFR in these tumors.

SIGNIFICANCE

The introduction of specific KRAS G12C inhibitors to the clinical practice in lung cancer has opened up opportunities that did not exist before. However, G12C alterations are only a subtype of all KRAS mutations observed. Given the high expression of AURKA in KRASmut NSCLC, our study could point to a potential therapeutic option for this subgroup of patients.

Nanogel enhances the efficacy of MLN8237 in treating hepatocellular carcinoma

MLN8237, a specific inhibitor of Aurora-A kinase, is proved to be a potential treatment strategy for hepatocellular carcinoma (HCC). Nanogels improve the efficacy of doxorubicin. Therefore, this study aims to investigate the increase in the effect of nanogels on MLN8237 in inhibiting HCC. Doxorubicin or MLN8237 was used as an anti-tumor drug models which were packaged by organic solvent volatilization method to obtain the doxorubicin-loaded nanogel and the MLN8237-loaded nanogel. Subsequently, CCK8 assay, cell cycle assay, apoptosis assay, real-time PCR, western blotting assay and animal experiments were used to detect the effects of MLN8237 nanogel on the proliferation, cell cycle, apoptosis, tumor growth, mRNA and protein levels of aurora-A and PUMA, and AKT phosphorylation levels in HCC cell lines. The results show that the nanogels can realize pH-regulated hydrophobicity reversal, have certain stability, and can realize lysosomal escape. Moreover, the MLN8237-loaded nanogel has a stronger ability to inhibit HCC cell proliferation, block cell cycle, promote apoptosis and inhibit tumor growth than free MLN8237 by suppressing aurora-A and AKT phosphorylation. In short, nanogel can enhance the efficacy of MLN8237.

Opportunities for Quantitative Translational Modeling in Oncology

A 2-day meeting was held by members of the UK Quantitative Systems Pharmacology Network () in November 2018 on the topic of Translational Challenges in Oncology. Participants from a wide range of backgrounds were invited to discuss current and emerging modeling applications in nonclinical and clinical drug development, and to identify areas for improvement. This resulting perspective explores opportunities for impactful quantitative pharmacology approaches. Four key themes arose from the presentations and discussions that were held, leading to the following recommendations: Evaluate the predictivity and reproducibility of animal cancer models through precompetitive collaboration. Apply mechanism of action (MoA) based mechanistic models derived from nonclinical data to clinical trial data. Apply MoA reflective models across trial data sets to more robustly quantify the natural history of disease and response to differing interventions. Quantify more robustly the dose and concentration dependence of adverse events through mathematical modelling techniques and modified trial design.

MLN8237 treatment in an orthoxenograft murine model for malignant peripheral nerve sheath tumors

OBJECTIVE

Malignant peripheral nerve sheath tumors (MPNSTs) are soft-tissue sarcomas arising from peripheral nerves. MPNSTs have increased expression of the oncogene aurora kinase A, leading to enhanced cellular proliferation. This makes them extremely aggressive with high potential for metastasis and a devastating prognosis; 5-year survival estimates range from a dismal 15% to 60%. MPNSTs are currently treated with resection (sometimes requiring limb amputation) in combination with chemoradiation, both of which demonstrate limited effectiveness. The authors present the results of immunohistochemical, in vitro, and in vivo analyses of MLN8237 for the treatment of MPNSTs in an orthoxenograft murine model.

METHODS

Immunohistochemistry was performed on tumor sections to confirm the increased expression of aurora kinase A. Cytotoxicity analysis was then performed on an MPNST cell line (STS26T) to assess the efficacy of MLN8237 in vitro. A murine orthoxenograft MPNST model transfected to express luciferase was then developed to assess the efficacy of aurora kinase A inhibition in the treatment of MPNSTs in vivo. Mice with confirmed tumor on in vivo imaging were divided into 3 groups: 1) controls, 2) mice treated with MLN8237, and 3) mice treated with doxorubicin/ifosfamide. Treatment was carried out for 32 days, with imaging performed at weekly intervals until postinjection day 42. Average bioluminescence among groups was compared at weekly intervals using 1-way ANOVA. A survival analysis was performed using Kaplan-Meier curves.

RESULTS

Immunohistochemical analysis showed robust expression of aurora kinase A in tumor cells. Cytotoxicity analysis revealed STS26T susceptibility to MLN8237 in vitro. The group receiving treatment with MLN8237 showed a statistically significant difference in tumor size compared with the control group starting at postinjection day 21 and persisting until the end of the study. The MLN8237 group also showed decreased tumor size compared with the doxorubicin/ifosfamide group at the conclusion of the study (p = 0.036). Survival analysis revealed a significantly increased median survival in the MLN8237 group (83 days) compared with both the control (64 days) and doxorubicin/ifosfamide (67 days) groups. A hazard ratio comparing the 2 treatment groups showed a decreased hazard rate in the MLN8237 group compared with the doxorubicin/ifosfamide group (HR 2.945; p = 0.0134).

CONCLUSIONS

The results of this study demonstrate that MLN8237 is superior to combination treatment with doxorubicin/ifosfamide in a preclinical orthoxenograft murine model. These data have major implications for the future of MPNST research by providing a robust murine model as well as providing evidence that MLN8237 may be an effective treatment for MPNSTs.

Development of new agents for peripheral T-cell lymphoma

INTRODUCTION

Peripheral T-cell lymphoma (PTCL) is a relatively rare, heterogeneous group of mature T-cell neoplasms generally associated with poor prognosis, partly because of refractoriness against conventional cytotoxic chemotherapies. To improve the outcome of patients with PTCL, the clinical development of several novel agents is currently under investigation.

AREAS COVERED

Since the first approval of pralatrexate (dihydrofolate reductase inhibitor) by the US Food and Drug Administration, belinostat, romidepsin (histone deacetylase inhibitors), and brentuximab vedotin (anti-CD30 antibody-drug conjugate) have been approved in the US, and many other countries. In addition, mogamulizumab (anti-CC chemokine receptor 4 antibody), chidamide (histone deacetylase inhibitor), and forodesine (purine nucleoside phosphorylase inhibitor) have been approved in Asian countries, including China, and Japan. In this review, we have summarized the available data regarding these approved agents and new agents currently under development for PTCL.

EXPERT OPINION

Novel agents will be a promising therapeutic option in selected patients with relapsed/refractory PTCL and will change the daily clinical practice in the treatment of PTCL. However, these are not a curative option when used as a single agent. Further clinical developments are expected, comprising 1) combination therapies of new agents with cytotoxic chemotherapies; 2) 'novel-novel' combinations; 3) immune therapies, including chimeric antigen receptor T-cell therapy; and 4) predictive marker analysis.

Quantitative translational modeling to facilitate preclinical to clinical efficacy & toxicity translation in oncology

Significant scientific advances in biomedical research have expanded our knowledge of the molecular basis of carcinogenesis, mechanisms of cancer growth, and the importance of the cancer immunity cycle. However, despite scientific advances in the understanding of cancer biology, the success rate of oncology drug development remains the lowest among all therapeutic areas. In this review, some of the key translational drug development objectives in oncology will be outlined. The literature evidence of how mathematical modeling could be used to build a unifying framework to answer these questions will be summarized with recommendations on the strategies for building such a mathematical framework to facilitate the prediction of clinical efficacy and toxicity of investigational antineoplastic agents. Together, the literature evidence suggests that a rigorous and unifying preclinical to clinical translational framework based on mathematical models is extremely valuable for making go/no-go decisions in preclinical development, and for planning early clinical studies.

Alisertib: a review of pharmacokinetics, efficacy and toxicity in patients with hematologic malignancies and solid tumors

INTRODUCTION

Aurora kinases are essential mediators in cell mitosis. Amplification of these kinases can lead to the development of malignancy and may be associated with inferior survival. Alisertib is an oral aurora kinase inhibitor which has been shown to induce cell-cycle arrest and apoptosis in preclinical studies. It is currently under investigation for a wide variety of malignancies including hematologic (specifically Non-Hodgkin's lymphoma) and solid tumors. Areas covered: A PubMed search was performed to identify clinical studies reporting outcomes with alisertib. Promising results are notable in patients with peripheral T cell lymphoma in particular, forming the basis for the first phase 3 randomized trial of alisertib. Although it did show encouraging response rates, it failed to demonstrate superiority over the comparator arm at an interim analysis, halting further enrollment. Expert opinion: Despite disappointing early results, alisertib remains under investigation in a number of cancer types both as monotherapy and in combination with traditional cytotoxic chemotherapy, with encouraging results. Most common toxicities in early trials include myelosuppression alopecia, mucositis and fatigue. The relatively manageable toxicity profile of alisertib along with ease of dosing may allow it to be combined with other oral agents or traditional chemotherapy across a wide variety of malignancy types.

A simple and rapid UHPLC-MS/MS method for the quantitation of the dual aurora kinase A/B inhibitor SCH-1473759 in murine plasma

The Aurora kinase family facilitates cell division through various processes and is overexpressed in a wide variety of human cancers, leading to aneuploidy. For that reason, these enzymes are currently targets of a rising class of anticancer drugs, with some molecules already in therapeutic use. In this study, a new UHPLC-MS/MS method was developed and validated to quantitate a new pan Aurora kinase inhibitor still in preclinical development, SCH-1473759. This bioanalytical method employed a liquid-liquid extraction from plasma using ethyl acetate before evaporation. Calibration range encompassed 0.5-2500ng/mL. The inter- and intra-day accuracy and precision were assessed over five quality control levels; all within limits required by the FDA guidelines. Assay applicability was demonstrated in a first-in-animals study with oral administration, where the maximum plasma concentration (34ng/mL) occurred at 1h, the half-life (1h) was consistent with a previous IV study, and oral bioavailability was poor (F=0.002).

Enhancing value of clinical pharmacodynamics in oncology drug development: An alliance between quantitative pharmacology and translational science

Clinical pharmacodynamic evaluation is a key component of the "pharmacologic audit trail" in oncology drug development. We posit that its value can and should be greatly enhanced via application of a robust quantitative pharmacology framework informed by biologically mechanistic considerations. Herein, we illustrate examples of intersectional blindspots across the disciplines of quantitative pharmacology and translational science and offer a roadmap aimed at enhancing the caliber of clinical pharmacodynamic research in the development of oncology therapeutics.

Aurora A Kinase Inhibition Selectively Synergizes with Histone Deacetylase Inhibitor through Cytokinesis Failure in T-cell Lymphoma

PURPOSE

Aurora A kinase (AAK) is expressed exclusively during mitosis, and plays a critical role in centrosome duplication and spindle formation. Alisertib is a highly selective AAK inhibitor that has demonstrated marked clinical activity of alisertib across a spectrum of lymphomas, though particularly in patients with T-cell lymphoma (TCL). We sought to compare and contrast the activity of alisertib in preclinical models of B-cell lymphoma (BCL) and TCL, and identify combinations worthy of clinical study. High-throughput screening of pralatrexate, the proteasome inhibitor (ixazomib), and the histone deacetylase (HDAC) inhibitor (romidepsin) revealed that only romidepsin synergized with alisertib, and only in models of TCL. We discovered that the mechanism of synergy between AAK inhibitors and HDAC inhibitors appears to be mediated through cytokinesis failure.

EXPERIMENTAL DESIGN

A high-throughput screening approach was used to identify drugs that were potentially synergistic in combination with alisertib. Live-cell imaging was used to explore the mechanistic basis for the drug: drug interaction between alisertib and romidepsin. An in vivo xenograft TCL model was used to confirm in vitro results.

RESULTS

In vitro, alisertib exhibited concentration-dependent cytotoxicity in BCL and TCL cell lines. Alisertib was synergistic with romidepsin in a T-cell-specific fashion that was confirmed in vivo. Live-cell imaging demonstrated that the combination treatment resulted in profound cytokinesis failure.

CONCLUSIONS

These data strongly suggest that the combination of alisertib and romidepsin is highly synergistic in TCL through modulation of cytokinesis and merits clinical development.

The role of alisertib in treatment of peripheral T-cell lymphomas

Peripheral T-cell lymphomas are aggressive lymphomas with poor outcomes for which novel treatments are urgently needed. Alisertib (MLN8237) is a second-generation oral Aurora A kinase inhibitor. Treatment with alisertib results in an accumulation of cells with abnormal mitotic spindles, leading to decreased proliferation and apoptosis in a range of human tumor cell lines. Alisertib has shown single-agent antitumor activity in animal xenograft models and promising antitumor activity alone or in combination with other agents in patients with solid and hematologic cancers, and T-cell lymphomas in particular. It is currently being tested in randomized controlled Phase III trials in relapsed/refractory peripheral T-cell lymphoma.

Inhibition of the Aurora A kinase augments the anti-tumor efficacy of oncolytic measles virotherapy

Oncolytic measles virus (MV) strains have demonstrated broad spectrum preclinical anti-tumor, including breast cancer. Aurora A kinase controls mitotic spindle formation and plays a critical role in malignant transformation. We hypothesized that, by causing mitotic arrest, the Aurora A kinase inhibitor MLN8237 (alisertib) can increase MV oncolytic effect and efficacy. Alisertib enhanced MV oncolysis in vitro and significantly improved outcome in vivo against breast cancer xenografts. In a disseminated MDA-231-lu-P4 lung metastatic model, the MV/alisertib combination treatment markedly increased median survival to 82.5 days with 20% of the animals being long term survivors vs. 48 days median survival for the control animals. Similarly, in a pleural effusion model of advanced breast cancer, the MV/alisertib combination significantly improved outcome with a 74.5 day median survival versus the single agent groups (57 and 40 days respectively). Increased viral gene expression and IL-24 upregulation were demonstrated, representing possible mechanisms for the observed increase in antitumor effect. Inhibiting Aurora A kinase with alisertib represents a novel approach to enhance measles virus-mediated oncolysis and antitumor effect. Both oncolytic MV strains and alisertib are currently tested in clinical trials, this study therefore provides the basis for translational applications of this combinatorial strategy in the treatment of patients with advanced breast cancer.

Combining an Aurora Kinase Inhibitor and a Death Receptor Ligand/Agonist Antibody Triggers Apoptosis in Melanoma Cells and Prevents Tumor Growth in Preclinical Mouse Models

PURPOSE

Preclinical studies show that inhibition of aurora kinases in melanoma tumors induces senescence and reduces tumor growth, but does not cause tumor regression. Additional preclinical models are needed to identify agents that will synergize with aurora kinase inhibitors to induce tumor regression.

EXPERIMENTAL DESIGN

We combined treatment with an aurora kinase A inhibitor, MLN8237, with agents that activate death receptors (Apo2L/TRAIL or death receptor 5 agonists) and monitored the ability of this treatment to induce tumor apoptosis and melanoma tumor regression using human cell lines and patient-derived xenograft (PDX) mouse models.

RESULTS

We found that this combined treatment led to apoptosis and markedly reduced cell viability. Mechanistic analysis showed that the induction of tumor cell senescence in response to the AURKA inhibitor resulted in a decreased display of Apo2L/TRAIL decoy receptors and increased display of one Apo2L/TRAIL receptor (death receptor 5), resulting in enhanced response to death receptor ligand/agonists. When death receptors were activated in senescent tumor cells, both intrinsic and extrinsic apoptotic pathways were induced independent of BRAF, NRAS, or p53 mutation status. Senescent tumor cells exhibited BID-mediated mitochondrial depolarization in response to Apo2L/TRAIL treatment. In addition, senescent tumor cells had a lower apoptotic threshold due to decreased XIAP and survivin expression. Melanoma tumor xenografts of one human cell line and one PDX displayed total blockage of tumor growth when treated with MLN8237 combined with DR5 agonist antibody.

CONCLUSIONS

These findings provide a strong rationale for combining senescence-inducing therapeutics with death receptor agonists for improved cancer treatment.

Phase II Intergroup Trial of Alisertib in Relapsed and Refractory Peripheral T-Cell Lymphoma and Transformed Mycosis Fungoides: SWOG 1108

PURPOSE

Aurora A kinase (AAK) is upregulated in highly proliferative lymphomas, suggesting its potential as a therapeutic target. Alisertib is a novel oral AAK inhibitor without adverse safety signals in early-phase studies that demonstrated preliminary activity in T-cell lymphoma. This phase II study was conducted to further investigate the efficacy of alisertib in relapsed or refractory peripheral T-cell non-Hodgkin lymphoma (PTCL).

PATIENTS AND METHODS

Eligible patients with histologically confirmed relapsed/refractory PTCL or transformed Mycosis fungoides (tMF) received alisertib 50 mg twice a day for 7 days on 21-day cycles.

RESULTS

Of 37 eligible patients, the histologic subtypes enrolled included PTCL not otherwise specified (n = 13), angioimmunoblastic T-cell lymphoma (n = 9), tMF (n = 7), adult T-cell lymphoma/leukemia (n = 4), anaplastic large-cell lymphoma (n = 2), and extranodal natural killer/T-cell lymphoma (n = 2). Grade 3 and 4 adverse events in ≥ 5% of patients included neutropenia (32%), anemia (30%), thrombocytopenia (24%), febrile neutropenia (14%), mucositis (11%), and rash (5%). Treatment was discontinued most commonly for disease progression. Among the PTCL subtypes, the overall response rate was 30%, whereas no responses were observed in tMF. Aurora B kinase was more commonly overexpressed than AAK in tumor specimens. Analysis of AAK, Aurora B kinase, MYC, BCL-2, phosphatidylinositol 3-kinase γ, and Notch1 expression revealed no association with response.

CONCLUSION

Alisertib has antitumor activity in PTCL, including heavily pretreated patients. These promising results are being further investigated in an ongoing international, randomized phase III trial comparing alisertib with investigator's choice in PTCL.

Optimizing oncology therapeutics through quantitative translational and clinical pharmacology: challenges and opportunities

Despite advances in biomedical research that have deepened our understanding of cancer hallmarks, resulting in the discovery and development of targeted therapies, the success rates of oncology drug development remain low. Opportunities remain for objective dose selection informed by exposure-response understanding to optimize the benefit-risk balance of novel therapies for cancer patients. This review article discusses the principles and applications of modeling and simulation approaches across the lifecycle of development of oncology therapeutics. Illustrative examples are used to convey the value gained from integration of quantitative clinical pharmacology strategies from the preclinical-translational phase through confirmatory clinical evaluation of efficacy and safety.

Dose selection for the investigational anticancer agent alisertib (MLN8237): Pharmacokinetics, pharmacodynamics, and exposure-safety relationships

We report population pharmacokinetic, pharmacodynamic, and pharmacokinetic-safety analyses to support phase II/III dose/regimen selection of alisertib, a selective Aurora A kinase (AAK) inhibitor. Phase I studies in adult cancer patients evaluated dosing on Days 1-7 in 21-day cycles or Days 1-21 in 35-day cycles, with corresponding maximum tolerated doses of 50 mg twice daily (BID) and 50 mg QD, respectively. Population pharmacokinetic analyses supported dose- and time-linear pharmacokinetics without identification of clinically meaningful covariates. Exposure-related increases in skin mitotic index and decreases in chromosomal alignment/spindle bipolarity in tumor mitotic cells confirmed AAK inhibition. Exposures in the 7-day schedule at or near 50 mg BID are expected to result in tumor AAK inhibition based on pharmacodynamic assessment in patient tumors. Exposure-safety analyses of data from patients receiving doses of 5-200 mg/day in the 7-day schedule support a low (∼7%) predicted incidence of dose-limiting toxicity at 50 mg BID. Taken together, these analyses support a pharmacologically active and acceptably tolerated dose range of alisertib for future clinical development.

Aurora kinase inhibitor patents and agents in clinical testing: an update (2011 - 2013)

INTRODUCTION

Aurora kinase A, B and C, members of serine/threonine kinase family, are key regulators of mitosis. As Aurora kinases are overexpressed in many of the human cancers, small-molecule inhibitors of Aurora kinase have emerged as a possible treatment option for cancer.

AREAS COVERED

In 2009 and 2011, the literature pertaining to Aurora kinase inhibitors and their patents was reviewed. Here, the aim is to update the information for Aurora kinase inhibitors in clinical trials and the patents filed between the years 2011 and 2013. Pubmed, Scopus®, Scifinder®, USPTO, EPO and www.clinicaltrials.gov databases were used for searching the literature and patents for Aurora kinase inhibitors.

EXPERT OPINION

Even though both Aurora sub-type selective as well as pan-selective inhibitors show preclinical and clinical efficacy, so far no Aurora kinase inhibitor has been approved for clinical use. Particularly, dose-limiting toxicity (neutropenia) is a key issue that needs to be addressed. Preliminary evidence suggests that the use of selective Aurora A inhibitors could avoid Aurora B-mediated neutropenia in clinical settings. Also, use of adjunctive agents such as granulocyte stimulating factor to overcome neutropenia associated with Aurora B inhibition could be an answer to overcome the toxicity and bring Aurora inhibitors to market in the future.