Nonclinical pharmacology and toxicology of the first biosimilar insulin glargine drug product (BASAGLAR®/ABASAGLAR®) approved in the European Union.

Basaglar®/Abasaglar® (Lilly insulin glargine [LY IGlar]) is a long-acting human insulin analogue drug product granted marketing authorisation as a biosimilar to Lantus® (Sanofi insulin glargine [SA IGlar]) by the European Medicines Agency. We assessed the similarity of LY IGlar to the reference drug product, European Union-sourced SA IGlar (EU-SA IGlar), using nonclinical in vitro and in vivo studies. No biologically relevant differences were observed for receptor binding affinity at either the insulin or insulin-like growth factor-1 (IGF-1) receptors, or in assays of functional or de novo lipogenic activity. The mitogenic potential of LY IGlar and EU-SA IGlar was similar when tested in both insulin- and IGF-1 receptor dominant cell systems. Repeated subcutaneous daily dosing of rats for 4 weeks with 0, 0.3, 1.0, or 2.0 mg/kg LY IGlar and EU-SA IGlar produced mortalities and clinical signs consistent with severe hypoglycaemia. Glucodynamic profiles of LY IGlar and EU-SA IGlar in satellite animals showed comparable dose-related hypoglycaemia. Severe hypoglycaemia was associated with axonal degeneration of the sciatic nerve; the incidence and severity were low and did not differ between LY IGlar and EU-SA IGlar. These results demonstrated no biologically relevant differences in toxicity between LY IGlar and EU-SA IGlar.

The Rat microRNA body atlas; Evaluation of the microRNA content of rat organs through deep sequencing and characterization of pancreas enriched miRNAs as biomarkers of pancreatic toxicity in the rat and dog.

BACKGROUND: MicroRNAs (miRNA) are ~19-25 nucleotide long RNA molecules that fine tune gene expression through the inhibition of translation or degradation of the mRNA through incorporation into the RNA induced silencing complex (RISC). MicroRNAs are stable in the serum and plasma, are detectable in a wide variety of body fluids, are conserved across veterinary species and humans and are expressed in a tissue specific manner. They can be detected at low concentrations in circulation in animals and humans, generating interest in the utilization of miRNAs as serum and/or plasma based biomarkers of tissue injury. MicroRNA tissue profiling in rodents has been published, but sample an insufficient number of organs of toxicologic interest using microarray or qPCR technologies for miRNA detection. Here we impart an improved rat microRNA body atlas consisting of 21 and 23 tissues of toxicologic interest from male and female Sprague Dawley rats respectively, using Illumina miRNA sequencing. Several of the authors created a dog miRNA body atlas and we collaborated to test miRNAs conserved in rat and dog pancreas in caerulein toxicity studies utilizing both species. RESULTS: A rich data set is presented that more robustly defines the tissue specificity and enrichment profiles of previously published and undiscovered rat miRNAs. We generated 1,927 sequences that mapped to mature miRNAs in rat, mouse and human from miRBase and discovered an additional 1,162 rat miRNAs as compared to the current number of rat miRNAs in miRBase version 21. Tissue specific and enriched miRNAs were identified and a subset of these miRNAs were validated by qPCR for tissue specificity or enrichment. As an example of the power of this approach, we have conducted rat and dog pancreas toxicity studies and examined the levels of some tissue specific and enriched miRNAs conserved between rat and dog in the serum of each species. The studies demonstrate that conserved tissue specific/enriched miRs-216a-5p, 375-3p, 148a-3p, 216b-5p and 141-3p are candidate biomarkers of pancreatic injury in the rat and dog. CONCLUSIONS: A microRNA body atlas for rat and dog was useful in identifying new candidate miRNA biomarkers of organ toxicity in 2 toxicologically relevant species.

In Vivo and In Vitro Characterization of Basal Insulin Peglispro: A Novel Insulin Analog.

The aim of this research was to characterize the in vivo and in vitro properties of basal insulin peglispro (BIL), a new basal insulin, wherein insulin lispro was derivatized through the covalent and site-specific attachment of a 20-kDa polyethylene-glycol (PEG; specifically, methoxy-terminated) moiety to lysine B28. Addition of the PEG moiety increased the hydrodynamic size of the insulin lispro molecule. Studies show there is a prolonged duration of action and a reduction in clearance. Given the different physical properties of BIL, it was also important to assess the metabolic and mitogenic activity of the molecule. Streptozotocin (STZ)-treated diabetic rats were used to study the pharmacokinetic and pharmacodynamic characteristics of BIL. Binding affinity and functional characterization of BIL were compared with those of several therapeutic insulins, insulin AspB10, and insulin-like growth factor 1 (IGF-1). BIL exhibited a markedly longer time to maximum concentration after subcutaneous injection, a greater area under the concentration-time curve, and a longer duration of action in the STZ-treated diabetic rat than insulin lispro. BIL exhibited reduced binding affinity and functional potency as compared with insulin lispro and demonstrated greater selectivity for the human insulin receptor (hIR) as compared with the human insulin-like growth factor 1 receptor. Furthermore, BIL showed a more rapid rate of dephosphorylation following maximal hIR stimulation, and reduced mitogenic potential in an IGF-1 receptor-dominant cellular model. PEGylation of insulin lispro with a 20-kDa PEG moiety at lysine B28 alters the absorption, clearance, distribution, and activity profile receptor, but does not alter its selectivity and full agonist receptor properties.

A phase I dose-escalation study to a predefined dose of a transforming growth factor-ß1 monoclonal antibody (TßM1) in patients with metastatic cancer.

Transforming growth factor ß (TGF-ß) plays an important role in cancer. Monoclonal antibodies (mAb) designed to specifically block the TGF-ß ligands, are expected to inhibit tumor progression in patients with metastatic cancer. TßM1 is a humanized mAb optimized for neutralizing activity against TGF-ß1. The objective of this clinical trial was to assess the safety and tolerability of TßM1 in patients with metastatic cancer. In this phase I, uncontrolled, non-randomized, dose-escalation study, 18 eligible adult patients who had measurable disease per RECIST and a performance status of ≤ 2 on the ECOG scale were administered TßM1 intravenously over 10 min at doses of 20, 60, 120 and 240 mg on day 1 of each 28-day cycle. Safety was assessed by adverse events (as defined by CTCAE version 3.0) and possible relationship to study drug, dose-limiting toxicities and laboratory changes. Systemic drug exposure and pharmacodynamic (PD) parameters were assessed. TßM1 was safe when administered once monthly. The pharmacokinetic (PK) profile was consistent with a mAb with a mean elimination half-life approximately 9 days. Although anticipated changes in PD markers such as serum VEGF, bFGF and mRNA expression of SMAD7 were observed in whole-blood, suggesting activity of TßM1 on the targeted pathway, these changes were not consistent to represent a PD effect. Additionally, despite the presence of an activated TGF-ß1 expression signature in patients' whole blood, the short dosing duration did not translate into significant antitumor effect in the small number of patients investigated in this study.

Deciphering ADME genetic data using an automated haplotype approach.

OBJECTIVE: To investigate the utility of statistical tools in translating Affymetrix Drug Metabolizing Enzyme and Transporter (DMET) Assay single-nucleotide polymorphisms (SNPs) into common consensus star alleles. METHODS: DMET SNP data from clinical trials in different ethnicities were pooled for analyses. Three different statistical methods, PHASE, Bayesian, and expectation-maximization (EM), were first assessed by comparing the consistency of calling CYP2D6 alleles among 1108 Asians and 55 Caucasians. Subsequently, the performance of EM in deriving haplotype calls was evaluated against the Affymetrix Translation Table for CYPs 2B6, 2C19, 2C9, and 3A4/5 in 582 Asians, 296 Caucasians, and 369 Africans. Selected DNA samples were sequenced to verify the EM-predicted haplotype calls. RESULTS: PHASE, Bayesian, and EM methods showed a similar CYP2D6 star allele call rate. The EM method, with a 0.99 posterior probability cutoff, was chosen for further evaluation because of its low false-positive call rate. Haplotype calls obtained with the EM method were consistent with the Affymetrix Translation Table more than 95% of the time for all five CYPs, except for the CYP2B6 calls in the African descents (83%). In addition, the EM method was superior to the Translation Table-only approach in resolving complex haplotype patterns, identifying novel haplotypes in CYP2B6 and CYP3A5, and determining genotype calls in the presence of missing SNP data. CONCLUSION: A statistical method such as EM could be used to augment the translation of DMET assay SNP data into star alleles, especially for complex genes, to facilitate full utilization and interpretation of clinical pharmacogenetics data.

Quantitative measurement of cell-free plasma DNA and applications for detecting tumor genetic variation and promoter methylation in a clinical setting.

An elevated cell-free DNA (cfDNA) level is often reported in patients with advanced cancer and is thought to represent nuclear material from a distant inaccessible tumor. cfDNA can become a valuable source to monitor tumor dynamics and evaluate genetic markers for predictive, prognostic, and diagnostic testing. DNA extraction and quantification were optimized with plasma collected from 20 patients with advanced cancer and 16 healthy controls. Plasma cfDNA from patients with advanced cancer was evaluated for TP53 genetic variation and methylation status of CpG islands in several promoters of known disease-related genes. Tumor biopsy and corresponding plasma specimens were collected from study participants to determine whether the same genetic variations were present in both samples. The cfDNA isolation method provided a lower DNA detection limit of 144 pg, equivalent to DNA from approximately 24 cells. Normal pooled human plasma cfDNA averaged 110 copies/mL of the ACTB gene. Extracted cfDNA was suitable for gene-specific variant detection, sequencing, and promoter methylation analysis. DNA extracted from tumor biopsy and corresponding plasma specimens from two patients with advanced cancer revealed an identical, nonsynonymous variant present in both samples. Immunohistochemical analysis confirmed the TP53 mutant phenotype in the tumor specimens. Quantitative measurement of cfDNA represents a useful biomarker to follow treatment outcome and is a valuable tool with which to characterize specific genetic alterations for both patient selection and personalized treatment.

Haplotype-based pharmacogenetic analysis for longitudinal quantitative traits in the presence of dropout.

We propose a variety of methods based on the generalized estimation equations to address the issues encountered in haplotype-based pharmacogenetic analysis, including analysis of longitudinal data with outcome-dependent dropouts, and evaluation of the high-dimensional haplotype and haplotype-drug interaction effects in an overall manner. We use the inverse probability weights to handle the outcome-dependent dropouts under the missing-at-random assumption, and incorporate the weighted L(1) penalty to select important main and interaction effects with high dimensionality. The proposed methods are easy to implement, computationally efficient, and provide an optimal balance between false positives and false negatives in detecting genetic effects.

Genetic variation in metabolizing enzyme and transporter genes: comprehensive assessment in 3 major East Asian subpopulations with comparison to Caucasians and Africans.

The advent of high-throughput technologies has proven valuable in the assessment of genetic differences and their effects on drug activation, metabolism, disposition, and transport. However, most studies to date have focused on a small number of genes or few alleles, some of which are rare and therefore observed infrequently or lacked rigorous ethnic characterization, thus reducing the ability to extrapolate within and among populations. In this study, the authors comprehensively assessed the allele frequencies of 165 variants comprising 27 drug-metabolizing enzyme and transporter (DMET) genes from 2188 participants across 3 major ethnic populations: Caucasians, Africans, and East Asians. This sample size was sufficiently large to demonstrate genetic differences among these major ethnic groups while concomitantly confirming similarities among East Asian subpopulations (Korean, Han Chinese, and Japanese). A comprehensive presentation of allele and genotype frequencies is included in the online supplement, and 3 of the most widely studied cytochrome P450 (CYP) genes, CYP2D6, CYP2C19, and CYP2C9; 2 non-CYP enzymes, NAT1 and TMPT; and 2 transporter genes, SLCO1B1 and SLCO2B1, are presented herein according to ethnic classification.

Genetic association study of treatment response with olanzapine/fluoxetine combination or lamotrigine in bipolar I depression.

OBJECTIVE: To evaluate common genetic variations for association with symptomatic improvement in bipolar I depression following treatment with olanzapine/fluoxetine combination (OFC) or lamotrigine. METHOD: Symptom improvement was assessed in 88 OFC-treated and 85 lamotrigine-treated white patients with bipolar I depression in the 7-week acute period of a randomized, double-blind study comparing OFC (6/25, 6/50, 12/25, or 12/50 mg/d [olanzapine/fluoxetine]) with lamotrigine (titrated to 200 mg/d). The original study was conducted from November 2003 to August 2004. Single nucleotide polymorphisms (SNPs) were genotyped in a set of 19 candidate genes corresponding to known sites of activity for olanzapine and fluoxetine or previously associated with antidepressant or antipsychotic response. Primary outcome was the reduction in Montgomery-Asberg Depression Rating Scale (MADRS) total score as assessed by the difference by genotype from baseline to week 7 from a mixed-effects repeated measures analysis with terms for visit, genotype, genotype-by-visit interaction, and baseline MADRS score as a covariate. RESULTS: SNPs within the dopamine D(3) receptor and histamine H(1) receptor (HRH1) genes were significantly associated with response to OFC. SNPs within the dopamine D(2) receptor, HRH1, dopamine beta-hydroxylase, glucocorticoid receptor, and melanocortin 2 receptor genes were significantly associated with response to lamotrigine. CONCLUSIONS: SNPs in specific candidate genes were associated with symptomatic improvement in a treatment-specific fashion. These results suggest the importance of dopaminergic effects in the treatment of patients with bipolar I depression and the potential utility of genotyping in selection of pharmacologic treatments for bipolar depression.

Dopamine receptor D3 genotype association with greater acute positive symptom remission with olanzapine therapy in predominately caucasian patients with chronic schizophrenia or schizoaffective disorder.

OBJECTIVE: To test association of dopamine receptor D3 (DRD-3) gene polymorphisms with olanzapine response in genetic samples from a registration phase clinical trial. METHODS: Eighty-eight acutely ill patients with schizophrenia or schizoaffective disorder were genotyped for ser-9-gly (rs6280) and 23 other polymorphisms within the DRD-3 gene. Allelic association of clinical response (mean baseline- to-endpoint reduction in Positive and Negative Syndrome Scale [PANSS] total and subscores) over 6 weeks of olanzapine treatment was assessed using repeated measures analysis of variance. RESULTS: Ser-9-gly genotypes were associated with differences in PANSS total score improvement from baseline to 6 weeks (p = 0.021). This association was most notable for improvement in positive symptoms (p = 0.0001), with patients with gly/gly genotype significantly more responsive. More patients with the gly/gly genotype had greater positive symptom remission (endpoint rating of minimal or none on all PANSS positive items, 39.1%) compared with patients with gly/ser and ser/ser genotypes (13.8%; p = 0.033). DRD-3 polymorphisms in disequilibrium with ser-9-gly were also significantly associated with greater positive symptom improvement (p = 0.0009-0.021), and one not in complete linkage disequilibrium, with lesser improvement (p = 0.027). CONCLUSIONS: Gly/gly DRD-3 genotype predicted statistically and clinically significantly better acute positive symptom reduction compared with other ser-9-gly genotypes in patients treated with olanzapine.

Multiplex assay for comprehensive genotyping of genes involved in drug metabolism, excretion, and transport.

BACKGROUND: Drug metabolism is a multistep process by which the body disposes of xenobiotic agents such as therapeutic drugs. Genetic variation in the enzymes involved in this process can lead to variability in a patient's response to medication. METHODS: We used molecular-inversion probe technology to develop a multiplex genotyping assay that can simultaneously test for 1227 genetic variants in 169 genes involved in drug metabolism, excretion, and transport. Within this larger set of variants, we performed analytical validation of a clinically defined core set of 165 variants in 27 genes to assess accuracy, imprecision, and dynamic range. RESULTS: In a test set of 91 samples, genotyping accuracy for the core set probes was 99.8% for called genotypes, with a 1.2% no-call (NC) rate. The majority of the core set probes (133 of 165) had < or = 1 genotyping failure in the test set; a subset of 12 probes was responsible for the majority of failures (mainly NC). Genotyping results were reproducible upon repeat testing with overall within- and between-run variation of 1.1% and 1.4%, respectively-again, primarily NCs in a subset of probes. The assay showed stable genotyping results over a 6-fold range of input DNA. CONCLUSIONS: This assay generates a comprehensive assessment of a patient's metabolic genotype and is a tool that can provide a more thorough understanding of patient-to-patient variability in pharmacokinetic responses to drugs.

The minimum significant ratio: a statistical parameter to characterize the reproducibility of potency estimates from concentration-response assays and estimation by replicate-experiment studies.

The authors show by illustration that procedures used to validate the reliability of single-concentration high-throughput screens such as the signal window and Z' factor do not ensure sufficient reliability in potency estimates from concentration response assays. They develop the minimum significant ratio as a statistical parameter to characterize the fold change between 2 compounds run in the same experiment that can be considered a real difference and use this parameter to characterize the reliability of the assay. They adapt methods described by Bland and Altman to develop a simple set of 2 experiments to estimate the minimum significant ratio and show that this protocol can identify assays that lack reproducibility. The methods are then extended to validate the equivalency of the same assay run by multiple laboratories.

Precision profiling and components of variability analysis for Affymetrix microarray assays run in a clinical context.

Although gene expression profiling using microarray technology is widely used in research environments, adoption of microarray testing in clinical laboratories is currently limited. In an attempt to determine how such assays would perform in a clinical laboratory, we evaluated the analytical variability of Affymetrix microarray probesets using two generations of human Affymetrix chips (U95Av2 and U133A). The study was designed to mimic potential clinical applications by using multiple operators, machines, and reagent lots, and by performing analyses throughout a period of several months. A mixed model analysis was used to evaluate the relative contributions of multiple factors to overall variability, including operator, instrument, run, cRNA/cDNA synthesis, and changes in reagent lots. Under these conditions, the average probeset coefficient of variation (CV) was relatively low for present probesets on both generations of chips (mean coefficient of variation, 21.9% and 27.2% for U95Av2 and U133A chips, respectively). The largest contribution to overall variation was chip-to-chip (residual) variability, which was responsible for between 40 to 60% of the total variability observed. Changes in individual reagent lots and instrumentation contributed very little to the overall variability. We conclude that the approach demonstrated here could be applied to clinical validation of Affymetrix-based assays and that the analytical precision of this technique is sufficient to answer many biological questions.

Post-transcriptional regulation of macrophage ABCA1, an early response gene to IFN-gamma.

Interferon-gamma (IFN-gamma) down-regulates receptors associated with reverse cholesterol transport including ABCA1. In the present study, the kinetics and mechanism of ABCA1 down-regulation were determined in mouse peritoneal macrophages. IFN-gamma decreased ABCA1 mRNA 1h following IFN-gamma addition and was maximally reduced by 3h. Down-regulation was protein synthesis dependent and involved post-transcriptional processes. ABCA1 message had a T(1/2) of 115 min in actinomycin treated cells that was reduced to a T(1/2) of 37 min by IFN-gamma. The decrease in message stability was also associated with a rapid loss of ABCA1 protein, significant 3h following IFN-gamma addition. The kinetics of ABCA1 message and protein decrease was consistent with the early IFN-gamma-induced changes in Stat1 phosphorylation and nuclear translocation observed in these cells. Therefore, ABCA1 can be considered as an early response gene to macrophage activation by IFN-gamma with down-regulation occurring by message destabilization.

A four component coupling strategy for the synthesis of D-phenylglycinamide-derived non-covalent factor Xa inhibitors.

A novel isonitrile derivative was synthesized and used in an Ugi four component coupling reaction to explore aryl group substitution effects on inhibition of the coagulation cascade serine protease factor Xa.

Synergistic antiviral activity of human interferon combinations in the hepatitis C virus replicon system.

The use of type I interferon (IFN), in combination with ribvirin, to treat chronic hepatitis C virus (HCV) infection has many drawbacks that prevent widespread application, ultimately leading to a significant unmet clinical need. Potential improvements in IFN therapy through targeted delivery, molecular alteration, and combination with other agents are ongoing in an attempt to decrease adverse effects and increase efficacy. In this report, the HCV replicon cell culture system was used to assess potential synergistic antiviral effects of multiple IFN species when administered in combination. Quantitative analysis of HCV replicon RNA by TaqMan (PE Applied Biosystems, Foster City, CA) and qualitative analysis of HCV protein expression were used to measure the antiviral efficacy of individual and combination IFN treatments, and synergistic responses of IFN combinations were determined through statistical analysis of the TaqMan results. We found that when administered simultaneously, type I/II IFN combinations (IFN-alpha2b + IFN-gamma or IFN-beta + IFN-gamma) resulted in dramatic antiviral synergy, whereas a type I/I combination (IFN-alpha2b + IFN-beta) demonstrated a slightly antagonistic profile. The synergistic effect is likely due to differential cell surface receptors and signaling pathways employed by types I and II IFNs. Conversely, all type I IFN species bind the same receptor and signal through similar pathways, possibly accounting for the nearly additive response observed. In support of this hypothesis, IFN treatment resulted in differential induction of Stat1 phosphorylation at Tyr 701. In conclusion, simultaneous type I/II IFN combination treatment may allow an overall decreased effective IFN dose, which may reduce the side effect profiles that hinder current therapy.