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Purpose: To characterize faricimab ocular and systemic pharmacokinetics (PK) in patients with neovascular age-related macular degeneration (nAMD) or diabetic macular edema (DME) and to assess the effect of faricimab ocular exposure on clinical endpoints., Methods: A population PK (popPK) model was developed using pooled data from phase 1 to 3 studies in patients with nAMD/DME. The dataset included 1095 faricimab aqueous humor (AH) concentrations from 284 patients and 8372 faricimab plasma concentrations from 2246 patients., Results: Following intravitreal administration, faricimab PK was accurately described by a linear three-compartment model with sequential vitreous humor (VH), AH, and plasma compartments. Faricimab VH elimination to AH is the slowest process, with an estimated half-life (t1/2) of 7.5 days. Due to flip-flop kinetics, plasma, AH, and VH concentrations declined in parallel. Disease had no effect on faricimab PK. Plasma exposure was ∼6000-fold lower than VH exposure. Age, anti-drug antibodies, body weight, and sex statistically significantly influenced PK parameters but had no clinically meaningful effect on ocular and systemic exposure. VH t1/2 alone could not explain faricimab dosing frequency. Exposure-response analyses showed similar gains in best-corrected visual acuity across faricimab exposure ranges and dosing regimens., Conclusions: Faricimab ocular and systemic pharmacokinetics were quantified and accurately described by the popPK model, developed using a large dataset from patients with nAMD/DME. Exposure-response analyses suggest that faricimab phase 3 dosing algorithms are appropriate to select the most suitable dosing regimen., Translational Relevance: The popPK analysis suggested that faricimab dosing frequency was influenced by several factors and not by VH t1/2 alone.

Purpose: Evaluate the ocular pharmacodynamics (PD) of intravitreal faricimab, a bispecific inhibitor of angiopoietin-2 (Ang-2) and vascular endothelial growth factor-A (VEGF-A), in patients with neovascular age-related macular degeneration (nAMD) or diabetic macular edema (DME)., Methods: Aqueous humor (AH) samples (1025 free Ang-2 concentrations and 1345 free VEGF-A concentrations) were collected from approximately 300 faricimab-treated patients with nAMD or DME in phase 2/3 trials. A population pharmacokinetic pharmacodynamic (popPKPD) model was developed to describe the dynamic effect of faricimab on free AH Ang-2 and VEGF-A., Results: Mean baseline Ang-2 concentrations were 8.1 and 13.4 pg/mL in patients with nAMD and DME, respectively. The corresponding mean baseline VEGF-A concentrations were 58 and 135 pg/mL, respectively. Overall, approximately 79% of Ang-2 (84% within 8 weeks postdose and 55% beyond 12 weeks postdose) and 7% of VEGF-A postdose observations were below the lower limit of quantification. Model-derived Ang-2 and VEGF-A concentration-time profiles for patients on every 4-week/every 8-week dosing were predicted to maintain greater than 50% suppression of Ang-2 concentrations for the entire dosing period. Patients on every 12-week/16-week dosing were predicted to have greater than 50% Ang-2 suppression for 12 or more weeks, whereas 50% VEGF-A suppression was maintained for 9 to 10 weeks. At 8 weeks postdose, the median Ang-2 concentrations remained suppressed by approximately 80%. At 16 weeks postdose, the median VEGF-A concentrations returned to baseline, but median Ang-2 levels remained below baseline., Conclusions: A popPKPD analysis demonstrated faricimab's rapid and sustained suppression of AH Ang-2 and VEGF-A., Translational Relevance: A popPKPD analysis suggested that sustained suppression of ocular Ang-2 contributes to faricimab's extended durability, observed in clinical trials.

Background: Objectively measuring Parkinson's disease (PD) signs and symptoms over time is critical for the successful development of treatments aimed at halting the disease progression of people with PD., Objective: To create a clinical trial simulation tool that characterizes the natural history of PD progression and enables a data-driven design of randomized controlled studies testing potential disease-modifying treatments (DMT) in early-stage PD., Methods: Data from the Parkinson's Progression Markers Initiative (PPMI) were analyzed with nonlinear mixed-effect modeling techniques to characterize the progression of MDS-UPDRS part I (non-motor aspects of experiences of daily living), part II (motor aspects of experiences of daily living), and part III (motor signs). A clinical trial simulation tool was built from these disease models and used to predict probability of success as a function of trial design., Results: MDS-UPDRS part III progresses approximately 3 times faster than MDS-UPDRS part II and I, with an increase of 3 versus 1 points/year. Higher amounts of symptomatic therapy is associated with slower progression of MDS-UPDRS part II and III. The modeling framework predicts that a DMT effect on MDS-UPDRS part III could precede effect on part II by approximately 2 to 3 years., Conclusions: Our clinical trial simulation tool predicted that in a two-year randomized controlled trial, MDS-UPDRS part III could be used to evaluate a potential novel DMT, while part II would require longer trials of a minimum duration of 3 to 5 years underscoring the need for innovative trial design approaches including novel patient-centric measures.

Aims: RO5459072, a cathepsin-S inhibitor, Biopharmaceutics Classification System class 2 and P-glycoprotein substrate, exhibited complex, nonlinear pharmacokinetics (PK) while fasted that seemed to impact both the absorption and the disposition phases. When given with food, all nonlinearities disappeared. Physiologically based PK (PBPK) modelling attributed those nonlinearities to dose-dependent solubilisation and colonic absorption. The objective of this population PK analysis was to complement the PBPK analysis., Methods: PK profiles in 39 healthy volunteers after first oral dosing (1-600 mg) while fasted or fed in single and multiple ascending dose studies were analysed using population compartmental modelling., Results: The PK of RO5459072 while fed was characterized by a 1-compartmental PK model with linear absorption and elimination. The nonlinearities while fasted were captured using dose dependent bioavailability and 2 sequential first-order absorption phases: one following drug administration and one occurring 11 hours later and only for doses >10 mg. The bioavailability in the first absorption phase increased between 1 and 10 mg and then decreased with dose, in agreement with in vitro dissolution and solubility studies. The remaining fraction of doses to be absorbed by the second absorption phase was found to have a bioavailability similar to that in the first absorption phase., Conclusion: The population PK model supported that dissolution- and solubility-limited absorption from the proximal and distal intestine alone explains the nonlinear PK of RO5459072 in fasted state and the linear PK in fed state. This work, together with the PBPK analysis, raised our confidence in the understanding of this complex PK., (© 2021 The Authors. British Journal of Clinical Pharmacology published by John Wiley & Sons Ltd on behalf of British Pharmacological Society.)

Purpose: What are the patient characteristics predictive of response to ranibizumab treatment?, Methods: Model-based characterization of best-corrected visual acuity (BCVA) time profiles of patients with neovascular age-related macular degeneration under ranibizumab or sham treatment based on 24-month observations of BCVA in 2419 patients from randomized multicenter phase 3 trials of ranibizumab: ANCHOR, MARINA, PIER, and HARBOR. Goodness-of-fit plots and precision of parameter estimates were used for measure of accuracy., Results: The model incorporates a long-term effect on disease progression and an additive and more potent short-term effect of ranibizumab. Response to ranibizumab treatment and progression of the disease were found to be a function of seven baseline characteristics (visual acuity, age, leakage size, central retinal lesion thickness, presence or absence of cyst, type of choroidal neovascularization (CNV), and size of pigment epithelium detachment). A composite score of these seven baseline characteristics was derived and used to categorize response to ranibizumab treatment. The ranibizumab treatment arms of two proof-of-concept studies held out from the model development were used to validate the methodology., Conclusions: A composite score based on seven patient characteristics prior to treatment could be used to discriminate patients with predicted insufficient response to anti-vascular endothelial growth factor treatment., Translational Relevance: The method could be used to create a virtual ranibizumab treatment arm in clinical trials or to reduce the size of a ranibizumab active control arm.

Aims: Codrituzumab (GC33) is a recombinant, humanized mAb that binds to glypican-3 (GPC3), an oncofetal protein highly expressed in hepatocellular carcinoma (HCC). This investigation aimed to identify clinically relevant factors that may affect the overall survival (OS) in HCC patients treated with codrituzumab and to quantitatively annotate their effects., Methods: Codrituzumab exposure was estimated by a population pharmacokinetics model with a nonlinear elimination pathway. Analysis of OS was performed using a time-to-event model in 181 patients with advanced HCC. The model was tested with the addition of various covariates, including levels of immune biomarkers, such as CD16 (measured in terms of molecules of equivalent soluble fluorophore; CD16 MESF ) and CD4, codrituzumab exposure and potential prognostic biomarkers of HCC such as baseline tumour size and soluble GPC3., Results: The time-to-event model estimated a prolonged OS (>3 months) in patients with codrituzumab exposure of ≥230 μg ml -1 and high CD16 MESF level (>5.26 × 10 5 MESF at least). The Weibull model was selected as the base hazard model. The baseline tumour size was included in the hazard model as a parameter independent of the drug effect. A logistic model was applied to explain the effects of drug exposure and CD16 MESF level., Conclusions: The final model indicates that adequate drug exposure plus a favourable immune environment are associated with prolonged OS. This quantitative model should be further validated with emerging data so as to guide study design in future clinical trials., (© 2018 The British Pharmacological Society.)

Aims: This study aimed at identifying pharmacological factors such as pharmacogenetics and drug exposure as new predictive biomarkers for delayed graft function (DGF), acute rejection (AR) and/or subclinical rejection (SCR)., Methods: Adult renal transplant recipients (n = 361) on cyclosporine-based immunosuppression were followed for the first 6 months after transplantation. The incidence of DGF and AR were documented as well as the prevalence of SCR at 6 months in surveillance biopsies. Demographic, transplant-related factors, pharmacological and pharmacogenetic factors (ABCB1, CYP3A5, CYP3A4, CYP2C8, NR1I2, PPP3CA and PPP3CB) were analysed in a combined approach in relation to the occurrence of DGF, AR and prevalence of SCR at month 6 using a proportional odds model and time to event model., Results: Fourteen per cent of the patients experienced at least one clinical rejection episode and only DGF showed a significant effect on the time to AR. The incidence of DGF correlated with a deceased donor kidney transplant (27% vs. 0.6% of living donors). Pharmacogenetic factors were not associated with risk for DGF, AR or SCR. A deceased donor kidney and acute rejection history were the most important determinants for SCR, resulting in a 52% risk of SCR at 6 months (vs. 11% average). In a sub-analysis of the patients with AR, those treated with rejection treatment including ATG, significantly less frequent SCR was found in the 6-month biopsy (13% vs. 50%)., Conclusions: Transplant-related factors remain the most important determinants of DGF, AR and SCR. Furthermore, rejection treatment with depleting antibodies effectively prevented SCR in 6-month surveillance biopsies., (© 2016 The British Pharmacological Society.)

Aim: Recent publications indicate a strong interest in applying Bayesian adaptive designs in first time in humans (FTIH) studies outside of oncology. The objective of the present work was to assess the performance of a new approach that includes Bayesian adaptive design in single ascending dose (SAD) trials conducted in healthy volunteers, in comparison with a more traditional approach., Methods: A trial simulation approach was used and seven different scenarios of dose-response were tested., Results: The new approach provided less biased estimates of maximum tolerated dose (MTD). In all scenarios, the number of subjects needed to define a MTD was lower with the new approach than with the traditional approach. With respect to duration of the trials, the two approaches were comparable. In all scenarios, the number of subjects exposed to a dose greater than the actual MTD was lower with the new approach than with the traditional approach., Conclusions: The new approach with Bayesian adaptive design shows a very good performance in the estimation of MTD and in reducing the total number of healthy subjects. It also reduces the number of subjects exposed to doses greater than the actual MTD., (© 2014 The British Pharmacological Society.)