Population pharmacokinetics of eptinezumab in paediatric patients with migraine and dose selection for phase 3 paediatric migraine studies.

This population pharmacokinetics (PopPK) analysis of eptinezumab used data from a paediatric study and a prior adult PopPK model to compare eptinezumab pharmacokinetics between adult and paediatric populations to determine dose recommendations for the phase 3 paediatric studies in migraine. The data consisted of 16 adolescents and 12 children with migraine, with corresponding demographics and 278 plasma concentrations in total. PopPK analysis was performed through nonlinear mixed effect modelling and with prior knowledge taken from a previous PopPK model in adults. A two-compartment model-adjusted for body weight impact on clearances and volumes of distributions and scaled to the power of 0.75 and 1.0, respectively-was found to adequately describe the paediatric pharmacokinetic data. The simulated population showed overlap in area under the plasma concentration-time curve and maximum plasma concentration between the paediatric and adult populations, with paediatric exposures within 10%-15% above adult levels on average. To provide comparable exposure to the approved adult doses, weight-based dosing adjustments are recommended for paediatric patients weighing ≤40 kg, while no adjustments are needed for patients weighing >40 kg. These results support the dosing strategy being used in the ongoing efficacy and safety studies with eptinezumab in children and adolescents with migraine.

Pharmacokinetics and Safety of Eptinezumab in Healthy Chinese Participants: A Randomized Clinical Trial.

BACKGROUND AND OBJECTIVE: Most evidence suggests that the pharmacokinetics of monoclonal antibodies (mAbs) are not meaningfully altered by patient characteristics, including racial/ethnic differences. Nevertheless, the pharmacokinetic profile of eptinezumab has not been evaluated in a Chinese population. This study was designed to confirm the hypothesis that the pharmacokinetic profile of the anti-calcitonin gene-related peptide mAb, eptinezumab, is similar in healthy Chinese individuals to that of healthy non-Asian individuals and non-Asian patients with migraine. METHODS: Over a study period of 12 weeks, healthy adult Chinese participants (N = 20) were randomized (1:1) to receive a single intravenous dose of eptinezumab 100 mg (n = 10) or 300 mg (n = 10) in a prospective, single-site, open-label parallel-group trial. Blood samples for the evaluation of plasma eptinezumab concentrations were obtained over 84 days, and standard pharmacokinetic parameters were derived. RESULTS: Mean maximum plasma concentrations (Cmax) of eptinezumab occurred 1.0-1.5 h post start of infusion, were similar between the 100 mg and 300 mg dose groups, and slowly declined in a biphasic manner. Cmax and area under the drug concentration-time curve (AUC) increased in a dose-proportional manner. Volume of distribution and clearance were similar between the 100 mg and 300 mg dose groups, and half-life was 22.5-28.1 days. Eptinezumab was generally well tolerated with no new safety signals identified. Only one participant, randomized to the 100 mg dose group, was positive for eptinezumab anti-drug antibodies, but negative for neutralizing antibodies, with no impact on pharmacokinetics. CONCLUSION: The pharmacokinetic profile of eptinezumab in healthy Chinese individuals was generally similar to that reported for non-Asian populations with migraine, and eptinezumab was generally well tolerated. Evaluation of immunogenicity showed no evidence of an impact of anti-drug antibodies or neutralizing antibodies on safety profiles. This supports the globally approved doses of 100 mg and 300 mg as being appropriate for Chinese patients with episodic migraine or chronic migraine.

Neutralizing Antibody Validation Testing and Reporting Harmonization.

Evolving immunogenicity assay performance expectations and a lack of harmonized neutralizing antibody validation testing and reporting tools have resulted in significant time spent by health authorities and sponsors on resolving filing queries. A team of experts within the American Association of Pharmaceutical Scientists' Therapeutic Product Immunogenicity Community across industry and the Food and Drug Administration addressed challenges unique to cell-based and non-cell-based neutralizing antibody assays. Harmonization of validation expectations and data reporting will facilitate filings to health authorities and are described in this manuscript. This team provides validation testing and reporting strategies and tools for the following assessments: (1) format selection; (2) cut point; (3) assay acceptance criteria; (4) control precision; (5) sensitivity including positive control selection and performance tracking; (6) negative control selection; (7) selectivity/specificity including matrix interference, hemolysis, lipemia, bilirubin, concomitant medications, and structurally similar analytes; (8) drug tolerance; (9) target tolerance; (10) sample stability; and (11) assay robustness.

Immunogenicity and safety of a proposed pegfilgrastim biosimilar MSB11455 versus the reference pegfilgrastim Neulasta® in healthy subjects: A randomized, double-blind trial.

MSB11455 is a proposed biosimilar to the currently licensed reference pegfilgrastim (Neulasta® ). This study was designed primarily to compare the immunogenicity of MSB11455 and Neulasta® . As secondary objectives, the safety and tolerability of MSB11455 and Neulasta® were also compared. Healthy adult subjects were randomized to either MSB11455 or Neulasta® , stratified by antipolyethylene glycol (PEG) antibody status at screening and study site. Subjects received a single subcutaneous dose of MSB11455 or Neulasta® (both 6 mg/0.6 mL) on day 1 of each of two study periods (same product in both periods), separated by a washout of 28-35 days. Immunogenicity samples were taken predose and up to day 84 post-first dose. Noninferiority was confirmed if the upper limit of the exact one-sided adjusted 95% confidence interval (CI) for the difference in antidrug antibody (ADA)-positive rates was < 10%. Safety was assessed throughout the study. Overall, 336 subjects were randomized and treated (N = 168 in each group). Noninferiority of MSB11455 over Neulasta® was demonstrated for immunogenicity; the difference in confirmed treatment-induced ADA-positive rate between MSB11455 and Neulasta® was -0.6% (upper limit of the exact one-sided adjusted 95% CI: 6.25%). ADAs were mostly directed against the PEG moiety of pegfilgrastim. No filgrastim-specific neutralizing antibodies were detected in either treatment group. Safety and tolerability were as expected for pegfilgrastim, and comparable between treatments. This study supports and strengthens the available evidence for the biosimilarity of MSB11455 to Neulasta® .

EBF recommendation on practical management of critical reagents for antidrug antibody ligand-binding assays.

Immunogenicity assays are required to measure antidrug antibodies that are generated against biotherapeutic modalities. As for any ligand-binding assays, critical reagents (CR) play a crucial role in immunogenicity assays, as the robustness and reliability of an assay are defined by the quality and long-term availability of these reagents. The current regulatory guidelines do not provide clear directions on how to implement and verify lot-to-lot changes of CR during an assay life cycle, or the acceptance criteria that should be used when implementing new lots of CR. These aspects were extensively discussed within the European Bioanalysis Forum community. In this paper, CR for immunogenicity assays are identified and the minimum requirements for introducing new lots of CR in immunogenicity assays are described.

Demonstrating biosimilar and originator antidrug antibody binding comparability in antidrug antibody assays: a practical approach.

Biosimilar drug development has brought new challenges to bioanalytical ligand-binding assays used to determine drug concentration, antidrug antibodies and neutralizing antibodies. One particular challenge is how to demonstrate that the antidrug antibody assay can adequately detect antibodies against both biosimilar and originator. In this paper, we review the current guidelines and literature for practical recommendations and present a gap analysis. Case examples of antibody binding comparability testing are presented, and the challenges and implications are discussed. Based on the lessons learned from our biosimilar assay applications, we recommend a bioanalytical comparability testing approach that is outlined and discussed.

EBF recommendation for stability testing of anti-drug antibodies; lessons learned from anti-vaccine antibody stability studies.

Long- and short-term stability testing of the analyte is one of the key parameters in bioanalytical method validation in support of pharmacokinetics. However, for immunogenicity testing, the scientific rationale for long- and short-term stability testing on quality control samples most often spiked with polyclonal antibody raised in a different species should be questioned. Therefore, the European Bioanalysis Forum (EBF) formed a Topic Team to discuss the scientific rationale for stability testing of anti-drug antibodies (ADAs). A review of EBF member companies' experience on ADA stability and on anti-vaccine antibodies from vaccine projects was the basis of this discussion. EBF recommends to perform short-term stability testing of the positive control, but not to perform long-term stability testing of ADAs in nonclinical and clinical studies.

Male circumcision and serologically determined human papillomavirus infection in a birth cohort.

Circumcision has been reported to protect against infection with human papillomavirus (HPV) in men, but results have been inconsistent. We followed males in a birth cohort born in Dunedin, New Zealand, in 1972 and 1973 from age 3 to 32 years. Seropositivity at age 32 years for the oncogenic types HPV-16 and 18, and the nononcogenic types 6 and 11, was studied in relation to maternal reports of circumcision status at age 3 for 450 men. Seropositivity to any of these types was associated with lifetime number of sexual partners (P = 0.03), and lower moral-religious emphasis of the family of origin (P < 0.001). Circumcision was not found to be protective, with the adjusted odds ratio (95% confidence interval) for HPV6/11/16/18 seropositivity among the circumcised compared with the uncircumcised being 1.4 (0.89-2.2).