Concentration-QT modelling shows no evidence of clinically significant QT interval prolongation with capivasertib at expected therapeutic concentrations.

Pharmacokinetics-matched digital electrocardiogram data (n = 503 measurements from 180 patients) collected in a first-in-human, multi-part, dose-escalation (from 80 to 800 mg) and dose expansion (at 480 mg) phase 1 study in patients with advanced solid malignancies, were used to assess potential risk of QT prolongation associated with the AKT inhibitor capivasertib. The relationship between plasma drug concentrations and baseline-adjusted Fridericia-corrected QT (ΔQTcF) values was estimated using a prespecified linear mixed-effects model. The model provided an unbiased reproduction of the experimental data set, estimating a small but positive correlation between capivasertib concentration and ΔQTcF. At the expected therapeutic dose (400 mg twice daily) the predicted mean ΔQTcF at the steady state maximum concentration was 3.97 ms with an upper limit of the 90% CI of 5.07 ms; below the 10 ms limit proposed by ICH E14 guidance. This analysis suggests that capivasertib is not expected to present a clinically significant risk for QT prolongation that is associated with pro-arrhythmic effects.

Population Pharmacokinetics of Semaglutide for Type 2 Diabetes.

INTRODUCTION: The aim of the present analysis was to characterise the absorption, distribution and elimination of semaglutide by means of population pharmacokinetic (PK) models using data from nine clinical pharmacology trials conducted in both healthy subjects and those with type 2 diabetes. METHODS: Data were obtained from trials with subcutaneous and intravenous administration of semaglutide that utilised frequent PK sampling and included a total of 353 subjects with 10,573 concentration values. RESULTS: Semaglutide PK properties across trials, drug product strengths and populations were well characterised by a two-compartment model with first-order absorption and elimination. For a typical subject with type 2 diabetes, clearance was estimated to be 0.0348 L/h [95% confidence interval (CI) 0.0327-0.0369 L/h], and the central and peripheral volumes were estimated to be 3.59 L (95% CI 3.28-3.90 L) and 4.10 L (95% CI 3.78-4.42 L), respectively (i.e. a total volume of distribution of 7.7 L). Interindividual variation was low (~ 15%) for both clearance and volumes of distribution, with low residual error (< 5%). Clearance and the total volume of distribution were approximately proportional to body weight. Minor differences were identified between healthy subjects and subjects with type 2 diabetes with respect to clearance and absorption rate, and between injection sites with respect to bioavailability. CONCLUSIONS: A novel two-compartment model was developed to provide the general characteristics of semaglutide absorption following subcutaneous administration, and of distribution and elimination across administration routes. Semaglutide PK was shown to be predictable across populations and administration routes and within subjects, and was primarily influenced by body weight. FUNDING: Novo Nordisk, Bagsværd, Denmark.

Concizumab restores thrombin generation potential in patients with haemophilia: Pharmacokinetic/pharmacodynamic modelling results of concizumab phase 1/1b data.

INTRODUCTION: Concizumab enhances thrombin generation (TG) potential in haemophilia patients by inhibiting tissue factor pathway inhibitor (TFPI). In EXPLORER3 (phase 1b), a dose-dependent pharmacokinetic/pharmacodynamic (PK/PD) relationship was confirmed between concizumab dose, free TFPI and TG potential. AIM: Determine the association between concizumab exposure, PD markers (free TFPI; peak TG) and bleeding episodes to establish the minimum concizumab concentration for achieving sufficient efficacy. METHODS: Free TFPI predictions were generated using an estimated concizumab-free TFPI exposure-response (Emax ) model based on concizumab phase 1/1b data for which simultaneously collected concizumab and free TFPI samples were available. Concizumab concentration at the time of a bleed was predicted using a PK model, based on available data for concizumab doses >50 µg/kg to ≤9 mg/kg. Peak TG vs concizumab concentration analyses and an Emax model were constructed based on EXPLORER3 observations. RESULTS: The Emax model showed a tight PK/PD relationship between concizumab exposure and free TFPI; free TFPI decreased with increasing concizumab concentration. A strong correlation between concizumab concentration and peak TG was observed; concizumab >100 ng/mL re-established TG potential to within the normal reference range. Estimated EC50 values for the identified concizumab-free TFPI and concizumab-TG potential models were very similar, supporting free TFPI as an important biomarker. A correlation between bleeding episode frequency and concizumab concentration was indicated; patients with a concizumab concentration >100 ng/mL experienced less frequent bleeding. The PK model predicted that once-daily dosing would minimize within-patient concizumab PK variability. CONCLUSION: Concizumab phase 2 trials will target an exposure ≥100 ng/mL, with a once-daily regimen.