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Pharmacodynamics-Immunogenicity Approach for Bioanalysis of Biological Drugs

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Pharmacodynamics-Immunogenicity Approach for Bioanalysis of Biological Drugs An integrated pharmacokinetics- pharmacodynamics-immunogenicity approach for bioanalysis of biological drugs Andrea Kiessling – Principal Scientist PK/PD Bioanalytics II Preclinical Safety / Biologics Safety & Disposition EBF 3rd Open Conference, 2 December 2010 Outline of the presentation PK-PD models for monoclonal antibodies - ligand binding models for soluble and cell surface targets - typical PK-PD behavior Integrated bioanalytical strategy: PK-PD and immunogenicity (IG) - ELISA formats to characterize PK and PD (soluble and cell surface targets) - impact of immunogenicity Examples - Example 1: soluble target; effect of immunogenicity on PK and PD - Example 2: cell surface target; detection of neutralizing immunogenicity from PK assay format - Example 3: cell surface target; effect of PK on PD Summary 2 | EBF 3rd Open Conference| Andrea Kiessling | 02 December 2010 A simple mAb-ligand PK-PD model input ligand mAb “A” + ligand “B” mAb – ligand complex “C” dose elimination elimination elimination mAb ligand mAb – ligand complex 3 | EBF 3rd Open Conference| Andrea Kiessling | 02 December 2010 mAb-ligand PK-PD binding model(s) Soluble target: Cellular target: mAb-ligand complex “tends” to mAb-ligand complex “tends” to take on the elimination take on the elimination characteristics of the mAb characteristics of the ligand - accumulation of “total” - TMDD apparent (PD marker) (inactive) ligand (PD marker) Lowe PJ et al: On setting the first dose in man: Quantitating biotherapeutic drug- target binding through PK and PD models Basic & Clin Pharmacology & Toxicology 2009; 106: 195-209 4 | EBF 3rd Open Conference| Andrea Kiessling | 02 December 2010 “Typical” PK-PD behavior – cellular target anti-CD11a mAb – Raptiva (efalizumab) mAb complex ligand increasing dose: change in IgG kinetics increasing dose: increases duration of effect Joshi et al An overview of the pharmacokinetics and pharmacodynamics of efalizumab: a monoclonal antibody approved for use in psoriasis J Clin Pharmacol 2006; 46: 10-20 5 | EBF 3rd Open Conference| Andrea Kiessling | 02 December 2010 “Typical” PK-PD behavior – soluble target anti-IL1 mAb – Ilaris (canakinumab) simulation 0.1, 0.3, 1, 3 and 10 mg/kg mAb complex ligand increasing dose: increasing dose: no change in IgG kinetics increases duration of effect 10 mg/kg 0.1 mg/kg 3 mg/kg 0.3 mg/kg 1 mg/kg 1 mg/kg 0.3 mg/kg 3 mg/kg 0.1 mg/kg 10 mg/kg 6 | EBF 3rd Open Conference| Andrea Kiessling | 02 December 2010 Outline of the presentation PK-PD models for monoclonal antibodies - ligand binding models for soluble and cell surface targets - typical PK-PD behavior Integrated bioanalytical strategy: PK-PD and immunogenicity (IG) - ELISA formats to characterize PK and PD (soluble and cell surface targets) - impact of immunogenicity Examples - Example 1: soluble target; effect of immunogenicity on PK and PD - Example 2: cell surface target; detection of neutralizing immunogenicity from PK assay format - Example 3: cell surface target; effect of PK on PD Summary 7 | EBF 3rd Open Conference| Andrea Kiessling | 02 December 2010 Bioanalytical strategy – Immunogenicity (IG) labelled drug labelled secondary antibody Anti-drug antibody Anti-drug antibody drug drug Plate based Plate Bridging format Sandwich format Anti-drug antibody Anti-drug antibody drug Protein G drug BIAcore Protein G format Direct format 8 | EBF 3rd Open Conference| Andrea Kiessling | 02 December 2010 Bioanalytical strategy – immunogenicity (IG) Initial screening assays for immunogenicity do not differentiate non-neutralizing vs neutralizing immunogenicity Immunogenicity to Fc region Neutralising immunogenicity mAb (drug) – labeled AHA mAb (drug) Biacore Bridging ELISA Biacore Bridging ELISA increase in clearance of mAb increase in clearance of mAb no effect on target binding decrease in capacity for target binding influence on PK and/or PD assays? 9 | EBF 3rd Open Conference| Andrea Kiessling | 02 December 2010 Bioanalytical strategy – pharmacokinetics (PK) Free-”bioactive” mAb labeled drug anti-human IgG labeled target drug drug drug anti-id or or anti-id or target or target target Sandwich ELISA Competitive ELISA Bridging assay Total mAb anti-human IgG drug target anti-human IgG Sandwich ELISA 10 | EBF 3rd Open Conference| Andrea Kiessling | 02 December 2010 Bioanalytical strategy – PK Impact of neutralizing (nIG) and non-neutralizing (non-nIG) immunogenicity neutralizing AHA non-neutralizing AHA anti-human IgG mAb (drug) nIG and non-nIG may interfere in the PK assay; detected as decrease in exposure ligand (short PK t½) sandwich ELISA mAb (drug) ligand nIG may intefere in the PK assay; mAb (drug) detected as either an increase or ligand ligand decrease in exposure (see example later) competitive ELISA bridging ELISA anti-human IgG non-nIG may interfere in the total PK mAb (drug) assay (pre-clinical); although nIG should not interfere in this assay sandwich ELISA 11 | EBF 3rd Open Conference| Andrea Kiessling | 02 December 2010 Bioanalytical strategy – PD (soluble ligand) total ligand (target capture) free ligand ligand –endogenous anti ligand Ab2 mAb (drug) ligand – endogenous anti ligand Ab4 mAb (drug) binding protein binding protein + + anti ligand Ab1 anti ligand Ab3 sandwich ELISA sandwich ELISA Technically challenging Technically very challenging . capture and detection reagents for . detection of free ligand ligand are selected which bind in (decreasing) in the presence of presence of mAb (drug) and increasing concentrations of total endogenous binding protein ligand (if relevant) . specificity and sensitivity (LLOQ) 12 | EBF 3rd Open Conference| Andrea Kiessling | 02 December 2010 Bioanalytical strategy – PD (soluble ligand) Impact of neutralizing (nIG) and non-neutralizing (non-nIG) immunogenicity total ligand (target capture) free ligand ligand –endogenous anti ligand Ab2 mAb (drug) ligand – endogenous anti ligand Ab mAb (drug) binding protein binding protein + + anti ligand Ab1 anti ligand Ab3 sandwich ELISA sandwich ELISA Immunogenicity to mAb (drug) should not directly interfere with PD assay format for either total or free ligand per se if appropriate reagents can be identified (i.e. different binding epitope(s) to drug) However: nIG may lead to decreased ligand capture and therefore a decrease in total ligand but also directly interfere with the PD assay if the drug is used for detection (see example) more rapid clearance of mAb (drug) from nIG and/or non-nIG will also lead to decreased ligand capture and a more rapid return to baseline free ligand 13 | EBF 3rd Open Conference| Andrea Kiessling | 02 December 2010 Outline of the presentation PK-PD models for monoclonal antibodies - ligand binding models for soluble and cell surface targets - typical PK-PD behavior Integrated bioanalytical strategy: PK-PD and immunogenicity (IG) - ELISA formats to characterize PK and PD (soluble target) - impact of immunogenicity Examples - Example 1: soluble target; effect of immunogenicity on PK and PD - Example 2: cell surface target; detection of neutralizing immunogenicity from PK assay format - Example 3: cell surface target; effect of PK on PD Summary 14 | EBF 3rd Open Conference| Andrea Kiessling | 02 December 2010 Example 1: background fully human IgG1 mAb; high affinity against soluble target target ligand can be measured in the systemic circulation at baseline high expression, high turnover? mAb acts as a “capture system” increase in mAb-ligand complex (detected in serum) is a “biomarker” for suppression of free ligand in interstitial space via a PK/PD model 15 | EBF 3rd Open Conference| Andrea Kiessling | 02 December 2010 Example 1: pre-clinical bioanalytical strategy neutralizing AHA non-neutralizing AHA PK assay: total mAb PD assay: total target (target capture) TMB substrate goat anti-mouse IgG HRP mouse anti-human IgG anti-human IgG mAb (drug) – add saturating amount mAb (drug) ligand anti-ligand Ab anti-human IgG sandwich ELISA sandwich ELISA 16 | EBF 3rd Open Conference| Andrea Kiessling | 02 December 2010 Example 1: PK-PD data (4wk DRF study cynomolgus monkey) 50 mg/kg mAb - days 0, 7, 14, 21 50 mg/kg mAb - days 0, 7, 14, 21 100000 100000 Total mAb Total mAb (t½ 4 days) 10000 10000 1000 1000 100 100 Concentration (nM) Concentration Concentration (nM) Concentration Total ligand Total ligand 10 10 1 1 0 7 14 21 28 0 7 14 21 28 Time (days) Time (days) NB One animal excluded from plot ... evidence of IG from PK and PD data after the third dose; confirmed on Biacore 17 | EBF 3rd Open Conference| Andrea Kiessling | 02 December 2010 Example 1: Conclusion In this example, mAb(drug)-ligand complex appears to be eliminated more rapidly than typical human IgG in cynomolgus monkey Immunogenicity apparent in both, PK and PD behavior No information about neutralizing capacity of the immune response; although PK-PD suggest that pre-dose on day 14 less target was captured as compared to the other two animals slight indication for neutralizing anti-drug antibodies at least at the beginning of the response 18 | EBF 3rd Open Conference| Andrea Kiessling | 02 December 2010 Example 2: background Fully human IgG1 mAb; high affinity against cell surface target At low concentrations, mAb (drug) is expected to be cleared by target mediated disposition (TMDD) No PD (receptor occupancy) as target cells present only at low level in serum 19 | EBF 3rd Open Conference| Andrea Kiessling | 02 December 2010 Example 2: pre-clinical bioanalytical strategy neutralizing AHA non-neutralizing AHA PK assay format 1: free “bioactive” mAb Immunogenicity assay: mAb (drug) AHA mAb (drug) ligand competitive ELISA Biacore PK assay format 2: free “bioactive” mAb ligand mAb (drug) ligand bridging ELISA 20 | EBF 3rd Open Conference| Andrea Kiessling | 02 December 2010 Example 2: PK and IG data (cynomolgus monkey) Three doses 100 mg/kg i.v. days 0, 7, 14 (n=3 animals) 10000 400 PK assay 350 1000 ligand /ml] 300 [RU] ug [ mAb (drug) 250 100 Untis ligand 200 bridging ELISA 10 150 Response 100 Rel Serum concentrationSerum 1 50 Immunogenicity 0 0 0 20 40 60 80 100 120 AHA Days mAb (drug) Biacore 21 | EBF 3rd Open Conference| Andrea Kiessling | 02 December 2010 Example 2: PK and IG data (cynomolgus monkey) Single dose 10 mg/kg i.v.
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