Abstract P4-16-14: Meta-analysis of Phase I pharmacokinetic/pharmacodynamic results of proposed biosimilar pegfilgrastim

Background

The long-acting granulocyte colony-stimulating factor (G-CSF) pegfilgrastim is widely used to prevent chemotherapy-induced neutropenia (CIN). Biosimilars could potentially improve sustainability of cancer care. Sandoz proposed biosimilar pegfilgrastim is under development and has been evaluated in Phase I and III studies.1,2 The current meta-analysis uses data from two Phase I studies in healthy volunteers (HVs) comparing pharmacokinetic (PK)/pharmacodynamic (PD) properties of Sandoz proposed biosimilar and EU-reference (Neulasta®) pegfilgrastim.

Methods

Data from two studies were included: a single-dose, double-blind, parallel-group study (study 1, data on file) and a single-dose, double-blind, crossover study (study 2),3 both in HVs randomized to receive proposed biosimilar or reference biologic (PK/PD analysis populations: study 1, n=93 per arm; study 2, n=169 per arm). Primary PK and PD parameters were AUC0–inf, AUC0–last, Cmax and ANC AUEC0–last, ANC Emax, respectively. For each parameter, geometric mean ratios and confidence intervals (CIs) for treatment comparisons (proposed biosimilar vs reference biologic) from the two studies were combined using meta-analytical techniques with a fixed-effects model. The 90% (PK) or 95% (PD) CIs were calculated and PK/PD biosimilarity was demonstrated if all CIs fell within equivalence margins of 80% to 125%. Non-baseline corrected PD parameters were used.

Results

The combined CIs of the geometric mean ratios for primary PK and PD parameters were all contained within the predefined equivalence margins. Safety, tolerability and immunogenicity were found to be similar between proposed biosimilar and EU-reference biologic in HVs (data not shown).

  Combined geometric mean with 90% (PK)/95% (PD) CICombined ratio with 90% (PK)/95% (PD) CI  Proposed biosimilarEU-referenceProposed biosimilar vs EU-referencePK parametersAUC0–last (ng×h/mL)N93+16993+169  Geometric mean 90% CI6823 [6122, 7603]6034 [5404, 6738]1.1385 [1.0606, 1.2221]AUC0–inf (ng×h/mL)N92+168a93+168a  Geometric mean 90% CI6973 [6268, 7757]6183 [5560, 6876]1.1335 [1.0570, 1.2156]Cmax (ng/mL)N93+16993+169  Geometric mean 90% CI196 [178, 216]180 [163, 198]1.0994 [1.0265, 1.1774]PD parametersAUEC0–last (109×h/L)N93+16993+169  Geometric mean 95% CI4986 [4855, 5121]4952 [4816, 5093]1.0119 [0.9959, 1.0281]Emax (109/L)N93+16993+169  Geometric mean 95% CI36.4 [35.3, 37.5]36.2 [35.1, 37.2]0.9981 [0.9790, 1.0175]AUC=area under serum-concentration curve; AUEC=area under effect curve; CI=confidence interval; Cmax=maximum observed serum concentration; Emax=maximum effect attributable to investigational medicinal product; PD=pharmacodynamic; PK=pharmacokinetic. aOne subject in study 2 had AUC0–inf extrapolated >20% and was excluded from AUC0–inf analysis

Conclusions

This meta-analysis of two Phase I studies supports PK/PD similarity of Sandoz proposed biosimilar to EU-reference pegfilgrastim. Also, no clinically meaningful differences in safety, tolerability and immunogenicity were found. Sandoz proposed biosimilar pegfilgrastim presents as a sustainable option to manage CIN in patients with cancer.

References

1Blackwell et al. Oncologist 2016;21:789–94

2Harbeck et al. Future Oncol 2016;12:1359–67

3Nakov et al. Cancer Res 2018;78:P3-14-10

Citation Format: Nakov R, Wang J, Chen Y, Bellon A, Gattu S, Krendyukov A, Li Y. Meta-analysis of Phase I pharmacokinetic/pharmacodynamic results of proposed biosimilar pegfilgrastim [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-16-14.

Safety and dose-dependency of eptacog beta (activated) in a dose escalation study of non-bleeding congenital haemophilia A or B patients, with or without inhibitors

INTRODUCTION

Varying initial doses of activated eptacog beta (recombinant human FVIIa, rhFVIIa) may provide therapeutic options when treating bleeding in patients with congenital haemophilia who have developed inhibitory antibodies to factor VIII (FVIII) or factor IX (FIX). This study evaluated escalated doses of a new rhFVIIa product as a prelude to selecting the doses for clinical efficacy evaluation in haemophilia patients.

AIM

To assess the safety, pharmacokinetics, and laboratory pharmacodynamics of 3 doses of rhFVIIa in non-bleeding patients with congenital haemophilia A or B with or without inhibitors.

METHODS

Adult male patients (18-75 years old) with congenital haemophilia A or B (with or without inhibitors) received infusions of rhFVIIa at doses of 25, 75 or 225 μg/kg body weight. Ten patients were treated at each dose level, and each patient received 2 different dose levels. Descriptive methods were used to analyse the data.

RESULTS

Administration of rhFVIIa at all doses was well tolerated. Pharmacokinetic analyses showed that peak FVIIa plasma levels (C_max ) were approximately proportional to dose and correlated well with peak thrombin generation. Total AUC_0-inf also was approximately dose proportional. Clot formation and duration correlated with FVIIa activity. Repeat doses did not produce an immunological response.

CONCLUSION

In the first dose-escalation study of rhFVIIa to support product registration, eptacog beta at doses of 25, 75, and 225 μg/kg was pharmacodynamically active and well tolerated in non-bleeding patients with congenital haemophilia A or B.

Potassium channel gene associations with joint processing speed and white matter impairments in schizophrenia

Patients with schizophrenia show decreased processing speed on neuropsychological testing and decreased white matter integrity as measured by diffusion tensor imaging, two traits shown to be both heritable and genetically associated indicating that there may be genes that influence both traits as well as schizophrenia disease risk. The potassium channel gene family is a reasonable candidate to harbor such a gene given the prominent role potassium channels play in the central nervous system in signal transduction, particularly in myelinated axons. We genotyped members of the large potassium channel gene family focusing on putatively functional single nucleotide polymorphisms (SNPs) in a population of 363 controls, 194 patients with schizophrenia spectrum disorder (SSD) and 28 patients with affective disorders with psychotic features who completed imaging and neuropsychological testing. We then performed three association analyses using three phenotypes - processing speed, whole-brain white matter fractional anisotropy (FA) and schizophrenia spectrum diagnosis. We extracted SNPs showing an association at a nominal P value of <0.05 with all three phenotypes in the expected direction: decreased processing speed, decreased FA and increased risk of SSD. A single SNP, rs8234, in the 3' untranslated region of voltage-gated potassium channel subfamily Q member 1 (KCNQ1) was identified. Rs8234 has been shown to affect KCNQ1 expression levels, and KCNQ1 levels have been shown to affect neuronal action potentials. This exploratory analysis provides preliminary data suggesting that KCNQ1 may contribute to the shared risk for diminished processing speed, diminished white mater integrity and increased risk of schizophrenia.

Association of Disrupted in Schizophrenia 1 (DISC1) missense variants with ultra-resistant schizophrenia

Three common missense variants of the Disrupted in Schizophrenia 1 (DISC1) gene, rs3738401 (Q264R), rs6675281 (L607F) and rs821616 (S704C), have been variably associated with the risk of schizophrenia. In a case-control study, we examine whether these gene variants are associated with schizophrenia and ultra-resistant schizophrenia (URS) in a population of French Caucasian patients. The URS phenotype is characterized according to stringent criteria as patients who experience no clinical, social and/or occupational remission in spite of treatment with clozapine and at least two periods of treatment with distinct conventional or atypical antipsychotic drugs. We find a significant association between DISC1 missense variants and URS. The association with rs3738401 remains significant after appropriate correction for multiple testing. These results suggest that the DISC1 rs3738401 missense variant is statistically linked with ultra-resistance to antipsychotic treatment.

New genes associated with schizophrenia in neurite formation: a review of cell culture experiments

New genes consistently associated with schizophrenia include NRG1, Akt, DISC-1 and dysbindin-1. Since these genes participate in neurotransmission, neuroplasticity and neurodevelopment it has not been easy to elucidate which of these roles are abnormal in patients with schizophrenia. Neurite formation is identified as a crucial stage in development, and it is proposed that a defect in neurite formation originating from abnormally encoded proteins by these new genes could be at least an in vitro marker that reflects the most consistent molecular and neuroanatomical findings in schizophrenia. A systematic review of the literature linking the process of neurite formation to genes with replicated evidence that supported their association with schizophrenia was conducted. In addition, an outline of the process of neurite formation was included. Neurite formation was shown to be induced by neuregulins, the product of the gene NRG1. The activation of Akt, a serine/threonine kinase, promoted neurite formation in six independent studies. Conversely, two studies found that Akt inhibits neurite outgrowth. Stronger evidence supporting an association with the new genes related to schizophrenia and neurite formation comes from DISC-1. Defects in DISC-1 protein were shown to directly alter the process of neurite formation. Dysbindin-1 has not yet been directly implicated in neurite outgrowth. These findings suggest that the proteins encoded by NRG1, Akt and DISC-1 are implicated in the process of neurite formation in cellular models as well as, at least in part, animal models during development. Abnormalities in this process could have potential etiologic implications for schizophrenia. Direct evidence, however, of abnormal neurite formation in patients with schizophrenia is still missing. Limitations to this model are identified.

Improved conformation-dependent immunoassay: suitability for human prion detection with enhanced sensitivity

The presence of pathogenic prion protein (PrP(Sc)) in lymphoid tissues of variant Creutzfeldt-Jakob disease (vCJD) patients raises questions as to whether prions may be present in bodily fluids as well. Currently, transgenic mice are highly sensitive in vivo tools for the study of prions in tissues or fluids containing high levels of normal prion protein (PrP(C)). We report here an in vitro assay with virtually equivalent sensitivity incorporating a capture antibody into a sandwich conformation-dependent immunoassay (CDI), resulting in 30- to 100-fold increased sensitivity compared with the original, direct CDI. Furthermore, spiking plasma with vCJD prions in different preparations demonstrated that sandwich CDI detects prions with different biophysical properties at high sensitivity, even without proteinase K pretreatment of samples. Thus, sandwich CDI represents a powerful tool to study prions in bodily fluids of CJD/vCJD patients, with a turnaround time of less than 24 h.

Melatonin prevents cytoskeletal alterations and oxidative stress induced by okadaic acid in N1E-115 cells

Progressive loss of neuronal cytoarchitecture is a major event that precedes neuronal death, both in neural aging and in neurodegenerative diseases. Cytoskeleton in neurodegenerative diseases is characterized by hyperphosphorylated tau assembled in neurofibrillary tangles. Tau protein promotes microtubule enlargement and its hyperphosphorylation inhibits tubulin assembly. Okadaic acid (OA) causes oxidative stress, tau hyperphosphorylation, and altered cytoskeletal organization similar to those observed in neurons of patients with dementia. Since melatonin acts by both enlarging microtubules and as a free-radical scavenger, in this work we studied the effects of melatonin on altered cytoskeletal organization induced by OA in N1E-115 neuroblastoma cells. Optic microscopy, morphometric analysis, and tubulin immunofluorescence staining of neuroblastoma cells incubated with 50 nM OA showed an intact microtubule network following the neurite profile similar to that observed in the vehicle-incubated cells when melatonin was added to the incubation media 2 h before OA. The melatonin effects on altered cytoskeletal organization induced by OA were dose-dependent and were not abolished by luzindole, the mt(1) melatonin antagonist receptor. Also, increased lipid peroxidation and augmented apoptosis in N1E-115 cells incubated with 50 nM OA were prevented by melatonin. The results support the hypothesis that melatonin can be useful in the treatment of neurodegenerative diseases.

Differentiation-dependent redistribution of heparan sulfate in epithelial intestinal Caco-2 cells leads to basolateral entry of cytomegalovirus

Human cytomegalovirus (HCMV) causes a broad spectrum of clinical manifestations in immunocompromised patients, including infection of the gastrointestinal tract. To investigate the role of epithelial cells in the gastrointestinal HCMV disease, we used the intestinal epithelial cell line Caco-2, which is permissive for HCMV replication. In differentiated Caco-2 cells, we showed previously that HCMV infection proceeds preferentially from the basolateral membrane, suggesting that receptors for HCMV may be contained predominantly in the basolateral membrane (A. Esclatine et al., 2000, J. Virol. 74, 513-517). Therefore, we examined expression and localization in Caco-2 cells of heparan sulfate (HS) proteoglycan and annexin II, previously implicated in initial events of HCMV infection. We observed that annexin II is expressed in Caco-2 cells, but is not essential for entry of HCMV. We showed that, during the differentiation process, HS, initially present on the entire surface of the membrane of undifferentiated cells, ultimately became sequestered at the basolateral cell surface of fully differentiated cells. We established by biochemical assays that membrane-associated HS proteoglycan mediates both viral attachment to, and subsequent infection of, Caco-2 cells, regardless of the cell differentiation state. Thus, the redistribution of HS is implicated in the basolateral entry of HCMV into differentiated Caco-2 cells.