Translation of Monoclonal Antibodies Pharmacokinetics from Animal to Human Using Physiologically Based Modeling in Open Systems Pharmacology (OSP) Suite: A Retrospective Analysis of Bevacizumab.

Interspecies translation of monoclonal antibodies (mAbs) pharmacokinetics (PK) in presence of target-mediated drug disposition (TMDD) is particularly challenging. Incorporation of TMDD in physiologically based PK (PBPK) modeling is recent and needs to be consolidated and generalized to provide better prediction of TMDD regarding inter-species translation during preclinical and clinical development steps of mAbs. The objective of this study was to develop a generic PBPK translational approach for mAbs using the open-source software (PK-Sim® and Mobi®). The translation of bevacizumab based on data in non-human primates (NHP), healthy volunteers (HV), and cancer patients was used as a case example for model demonstration purpose. A PBPK model for bevacizumab concentration-time data was developed using data from literature and the Open Systems Pharmacology (OSP) Suite version 10. PK-sim® was used to build the linear part of bevacizumab PK (mainly FcRn-mediated), whereas MoBi® was used to develop the target-mediated part. The model was first developed for NHP and used for a priori PK prediction in HV. Then, the refined model obtained in HV was used for a priori prediction in cancer patients. A priori predictions were within 2-fold prediction error (predicted/observed) for both area under the concentration-time curve (AUC) and maximum concentration (Cmax) and all the predicted concentrations were within 2-fold average fold error (AFE) and average absolute fold error (AAFE). Sensitivity analysis showed that FcRn-mediated distribution and elimination processes must be accounted for at all mAb concentration levels, whereas the lower the mAb concentration, the more significant the target-mediated elimination. This project is the first step to generalize the full PBPK translational approach in Model-Informed Drug Development (MIDD) of mAbs using OSP Suite.

Determination of the Optimal Single Dose Treatment for Acoziborole, a Novel Drug for the Treatment of Human African Trypanosomiasis: First-in-Human Study.

BACKGROUND AND OBJECTIVES: Acoziborole is a novel boron-containing candidate developed as an oral drug for the treatment of human African trypanosomiasis (HAT). Results from preclinical studies allowed progression to Phase 1 trials. We aimed to determine the best dose regimen for all stages of HAT. METHODS: Acoziborole was assessed in 128 healthy adult males of sub-Saharan African origin living in France. The study included a single oral administration of a 20- to 1200-mg dose in a randomised double-blind study in cohorts of 8 (6 active, 2 placebo) to assess safety, tolerability, and pharmacokinetics. In three additional open cohorts of 6 participants, the effect of activated charcoal was evaluated, bioequivalence of capsules versus tablets was assessed, and safety in the 960-mg tablet cohorts was monitored. RESULTS: Acoziborole was well tolerated at all doses tested; no dose-related adverse events were observed. The drug appeared rapidly in plasma (at 1 h), reached tmax between 24 and 72 h, and remained stable for up to 96 h, after which a slow decrease was quantifiable until 14 weeks after dosing. Charcoal had little impact on the enterohepatic recirculation effect, except for the 20-mg dose. Bioequivalence between capsule and tablet formulations was demonstrated. The therapeutic single dose for administration under fasted conditions was fixed to 960 mg. The maximum administered dose was 1200 mg. CONCLUSIONS: This study showed that acoziborole could be safely assessed in patients as a potential single-dose oral cure for both stages of gambiense HAT. TRIAL REGISTRATION: The study was registered with ClinicalTrials.gov: NCT01533961.

Review of the Existing Translational Pharmacokinetics Modeling Approaches Specific to Monoclonal Antibodies (mAbs) to Support the First-In-Human (FIH) Dose Selection.

The interest in therapeutic monoclonal antibodies (mAbs) has continuously growing in several diseases. However, their pharmacokinetics (PK) is complex due to their target-mediated drug disposition (TMDD) profiles which can induce a non-linear PK. This point is particularly challenging during the pre-clinical and translational development of a new mAb. This article reviews and describes the existing PK modeling approaches used to translate the mAbs PK from animal to human for intravenous (IV) and subcutaneous (SC) administration routes. Several approaches are presented, from the most empirical models to full physiologically based pharmacokinetic (PBPK) models, with a focus on the population PK methods (compartmental and minimal PBPK models). They include the translational approaches for the linear part of the PK and the TMDD mechanism of mAbs. The objective of this article is to provide an up-to-date overview and future perspectives of the translational PK approaches for mAbs during a model-informed drug development (MIDD), since the field of PK modeling has gained recently significant interest for guiding mAbs drug development.

Absence of QTc prolongation in a thorough QT study with imeglimin, a first in class oral agent for type 2 diabetes mellitus.

PURPOSE: Imeglimin is the first in a new class of oral antidiabetic agents, the glimins, currently in development to improve glycemic control in patients with type 2 diabetes mellitus. A thorough QT study was conducted to establish electrophysiological effects of therapeutic and supratherapeutic doses of imeglimin on cardiac repolarization. METHODS: In this randomized, double-blind, four-period, placebo and active controlled crossover study, healthy subjects were administered a single dose of imeglimin 2250 mg, imeglimin 6000 mg, moxifloxacin 400 mg, and placebo. 12-Lead Holter ECGs were recorded from 1 h before dosing until at least 24 h after each dose. This study was performed at a single-center inpatient clinical pharmacology unit. RESULTS: The upper bound of the two-sided 90% confidence interval for time-matched, placebo-subtracted, baseline-adjusted QTc intervals (ΔΔQTcF) did not exceed the regulatory threshold of 10 ms in any of the imeglimin dose groups. There were no QTcF values above 500 ms nor changes from pre-dose in QTcF above 60 ms in the imeglimin groups. Imeglimin did not exert a relevant effect on heart rate and PR or QRS intervals. Assay sensitivity was demonstrated by the effect of moxifloxacin 400 mg, with a lower bound two-sided 90% confidence interval for ΔΔQTcF of 10.6 ms. CONCLUSION: This thorough QT study demonstrated that therapeutic and supratherapeutic exposures of imeglimin did not induce a QT/QTc prolongation with a strong confidence as evidenced by the assay sensitivity. TRIAL REGISTRATION NUMBER/DATE: NCT02924337/ October 5, 2016.

Randomized study of the effect of gadopiclenol, a new gadolinium-based contrast agent, on the QTc interval in healthy subjects.

AIMS: We investigated the effect of gadopiclenol, a new gadolinium-based contrast agent, on the QTc interval at clinical and supraclinical dose, considering the relative hyperosmolarity of this product. METHODS: This was a single centre, randomized, double-blind, placebo- and positive-controlled, 4-way crossover study. Forty-eight healthy male and female subjects were included to receive single intravenous (i.v.) administrations of gadopiclenol at the clinical dose of 0.1 mmol kg-1 , standard for current gadolinium-based contrast agents, the supraclinical dose of 0.3 mmol kg-1 , placebo and a single oral dose of 400 mg moxifloxacin. RESULTS: The largest time-matched placebo-corrected, mean change from-baseline in QTcF (ΔΔQTcF) was observed 3 hours after administration of 0.1 mmol kg-1 gadopiclenol (2.39 ms, 90% confidence interval [CI]: 0.35, 4.43 ms) and 5 minutes after administration of 0.3 mmol kg-1 (4.81 ms, 90%CI: 2.84, 6.78 ms). The upper limit of the 90% CI was under the threshold of 10 ms, demonstrating no significant effect of gadopiclenol on QTc interval. From 1.5 to 4 hours postdose moxifloxacin, the lower limit of the 90% CI of ΔΔQTcF exceeded 5 ms demonstrating assay sensitivity. Although there was a positive slope, the concentration-response analysis estimated that the values of ΔΔQTcF at the maximal concentration of gadopiclenol at 0.1 and 0.3 mmol kg-1 were 0.41 and 2.23 ms, respectively, with the upper limit of the 90% CI not exceeding 10 ms. No serious or severe adverse events or treatment discontinuations due to adverse events were reported. CONCLUSION: This thorough QT/QTc study demonstrated that gadopiclenol did not prolong the QT interval at clinical and supraclinical doses and was well tolerated in healthy volunteers. The positive slope of the QTc prolongation vs concentration relationship suggests that hyperosmolarity could be associated with QTc prolongation. However, the amplitude of this effects is unlikely to be associated with proarrhythmia.

Evaluation of the effects on the QT-interval of 4 artemisinin-based combination therapies with a correction-free and heart rate-free method.

Several antimalarial drugs are known to prolong ventricular repolarization as evidenced by QT/QTc interval prolongation. This can lead to Torsades de Pointes, a potentially lethal ventricular arrhythmia. Whether this is the case with artemisinin-based combination therapies (ACTs) remains uncertain. Assessment of the extent of QTc prolongation with antimalarials is hampered by important variations of heart rate during malaria crises and previous studies have reported highly variable values of QTc prolongations with ACTs. We assessed QTc prolongation with four ACTs, using high quality ECG recording and measurement techniques, during the first episode of malaria in 2,091 African patients enrolled in the WANECAM study which also monitored clinical safety. Using an original and robust method of QTc assessment, independent from heart rate changes and from the method of QT correction, we were able to accurately assess the extent of mean maximum QTc prolongation with the four ACTs tested. There was no evidence of proarrhythmia with any treatment during the study although dihydroartemisinin-piperaquine, artesunate-amodiaquine and artemether-lumefantrine significantly prolonged QTc. The extent of prolongation of ventricular repolarization can be accurately assessed in studies where heart rate changes impede QTc assessment.

Effects of Dihydroartemisinin-Piperaquine Phosphate and Artemether-Lumefantrine on QTc Interval Prolongation.

QT/QTc interval prolongation reflects delayed cardiac repolarization which can lead to Torsade de Pointes and sudden death. Many antimalarial drugs prolong QT/QTc interval. However, due to confounding factors in patients with malaria, the precise extent of this effect has been found to be highly variable among studies. We compared the effects of dihydroartemisinin-piperaquine phosphate (DHA-PQP) and artemether-lumefantrine (A-L) on QT interval duration in healthy volunteers. In this randomized, parallel groups, active moxifloxacin- and placebo-controlled study, prolongation of the QT/QTc interval following treatment with DHA-PQP in fasted and fed condition and A-L in fed state was investigated in healthy subjects (n = 287; Clinicaltrials.gov: NCT01103830). DHA-PQP resulted in significant mean (95% confidence interval (CI)) maximum increases in QTc Fridericia (QTcF) of 21.0 ms (15.7, 26.4) for DHA-PQP fasted, 35.9 ms (31.1, 40.6) for DHA-PQP high-fat/low-caloric and 46.0 ms (39.6, 52.3) for DHA-PQP high-fat/high-caloric breakfast. For A-L, the largest difference from baseline relative to placebo was 9.9 ms (95% CI: 6.8, 12.9). Increases in QTcF related to maximum plasma concentrations of piperaquine. Moxifloxacin demonstrated assay sensitivity. Increases in QTcF following DHA-PQP and A-L were clinically relevant. Food increased piperaquine exposure and QTcF interval prolongation emphasizing the need to administer DHA-PQP in the fasting state.

A Pharmacokinetics, Efficacy, and Safety Study of Gadoterate Meglumine in Pediatric Subjects Aged Younger Than 2 Years.

OBJECTIVES: The primary objective of this study was to investigate the pharmacokinetic profile of gadoterate meglumine in pediatric patients younger than 2 years; the secondary objectives were to document its efficacy and safety. MATERIAL AND METHODS: This was a Phase IV open-label, prospective study conducted in 9 centers (4 countries). Forty-five patients younger than 2 years with normal estimated glomerular filtration rate and scheduled to undergo routine gadolinium-enhanced magnetic resonance imaging (MRI) of any organ were included and received a single intravenous injection of gadoterate meglumine (0.1 mmol/kg). To perform the population pharmacokinetics analysis, 3 blood samples per subject were drawn during 3 time windows at time points allocated by randomization. RESULTS: Gadoterate meglumine concentrations were best fitted using a 2-compartmental model with linear elimination from central compartment. The median total clearance adjusted to body weight was estimated at 0.06 L/h per kg and increased with estimated glomerular filtration rate according to a power model. The median volume of distribution at steady state (Vss) adjusted to body weight was estimated at 0.047 L/kg. Estimated median terminal half-life (t1/2ß) was 1.35 h, and the median systemic exposure (area under the curve) was 1591 µmol h/L. Efficacy was assessed by comparing precontrast +postcontrast images to precontrast images in a subset of 28 subjects who underwent an MRI examination of brain, spine, and associated tissues. A total of 28 lesions were identified and analyzed in 15 subjects with precontrast images versus 30 lesions in 16 subjects with precontrast + postcontrast images. Lesion visualization was improved with a mean (SD) increase in scores at subject level of 0.7 (1.0) for lesion border delineation, 0.9 (1.6) for internal morphology, and 3.1 (3.2) for contrast enhancement. Twenty-six adverse events occurred postinjection in 13 subjects (28.9%), including 3 serious reported in 1 subject (2.2%). One subject (2.2%) experienced 1 rash of moderate intensity considered as related to gadoterate meglumine. CONCLUSIONS: The pharmacokinetic profile of gadoterate meglumine after a single intravenous injection of 0.1 mmol/kg was appropriately described in newborns and infants younger than 2 years, for whom no dose adjustment is required. The improved efficacy of gadoterate meglumine for contrast-enhanced MRI examination of brain, spine, and associated tissues, as well as its good safety profile, was also demonstrated in this population.

Determination of an optimal dosing regimen for fexinidazole, a novel oral drug for the treatment of human African trypanosomiasis: first-in-human studies.

BACKGROUND AND OBJECTIVES: Fexinidazole is a 5-nitroimidazole recently included in a clinical efficacy trial as an oral drug for the treatment of human African trypanosomiasis (HAT). Preclinical studies showed it acts as a pharmacologically active pro-drug with two key active metabolites: sulfoxide and sulfone (the most active metabolite). The present studies aimed to determine the best dose regimen for the treatment of stage 2 sleeping sickness patients, which could eventually also treat stage 1 patients. METHODS: Fexinidazole was assessed in 154 healthy adult male subjects of sub-Saharan African origin. Three initial first-in-human studies and two additional studies assessed a single ascending dose and multiple ascending doses (both under fasted conditions), tablet versus suspension formulation and food effect (fasted vs. high-fat meal and field-adapted food), and multiple ascending doses with a loading dose regimen under fed conditions. RESULTS: Fexinidazole was well-tolerated in a single dose from 100 to 3,600 mg, with quick absorption of the parent drug and rapid metabolism into sulfoxide [time to maximum concentration (t max) 2-5 h] and sulfone (t max 18-24 h). The tablet formulation was approximately 25 % less bioavailable than the suspension, and food intake increased drug absorption and plasma concentrations of fexinidazole and its two metabolites by approximately 200 %. Fourteen-day multiple ascending dosing administered up to 3,600 mg/day in fasted conditions showed that fexinidazole was generally well-tolerated (mild to moderate, spontaneously reversible drug-related adverse events). Following the high-fat food effect finding, another study was conducted to evaluate the impact of a low-fat regimen closer to that of the target population, showing that the type of meal does not influence fexinidazole absorption. The last study showed that a loading dose of 1,800 mg/day for 4 days followed by a 1,200 mg/day regimen for 6 days with a normal meal provided the desired exposure of fexinidazole and its metabolites, particularly sulfone, with good tolerability. Based on preclinical evidence from a chronic infection mouse model, systemic drug concentrations obtained are expected to be clinically effective in stage 2 HAT. CONCLUSIONS: These studies show that fexinidazole can be safely assessed in patients as a potential oral cure for both stages of HAT.

Mutations associated with virological response to darunavir/ritonavir in HIV-1-infected protease inhibitor-experienced patients.

OBJECTIVE: The aim of the study was to identify a pattern of protease gene mutations associated with the virological response to darunavir/ritonavir-based regimens. PATIENTS AND METHODS: We analysed 153 treatment-experienced patients receiving a darunavir/ritonavir salvage regimen as a sole protease inhibitor (PI). Virological response was defined as an HIV-1 RNA load of <200 copies/mL at month 3. The impact of individual protease gene mutations on the virological response to darunavir/ritonavir was examined, and the combination of mutations most strongly associated with the virological response was identified. RESULTS: The baseline median HIV RNA level was 4.7 log(10) copies/mL and the median CD4 cell count was 142 cells/mm(3). At month 3, 55% of patients had a virological response and the median fall in viral load from baseline was 1.7 log(10) copies/mL. All the patients had detectable darunavir concentrations at month 3. Cochran-Armitage procedure identified eight mutations with a negative impact on the virological response, namely K14R, K20I, E34Q, I47V, I54M, K55R, T74P and I84V; and two mutations (E35D and V82A) with a positive impact. In multivariate analyses, our genotypic scores were highly predictive of the virological response at month 3, along with the baseline plasma viral load and enfuvirtide co-prescription to enfuvirtide-naive patients. CONCLUSIONS: Among the eight mutations with a negative impact on the virological response, I47V, I54M, T74P and I84V were previously described as darunavir resistance-associated mutations. Some PI resistance mutations had a positive impact on the virological response. These findings might help to explain the potency of darunavir/ritonavir on PI-resistant HIV.