Negative Food Effect of Danirixin: Use of PBPK Modelling to Explore the Effect of Formulation and Meal Type on Clinical PK.

PURPOSE: To use physiologically-based pharmacokinetic (PBPK) modelling to explore the food effect of different DNX hydrobromide (HBr) hemihydrate salt tablet formulations using biorelevant dissolution. METHODS: Compendial dissolution using a paddle method and TIM-1 biorelevant dissolution were performed and incorporated into a previously reported PBPK model. A two-part clinical study evaluated tablet formulations in the fasted/fed (high fat) state (Part A), and the impact of food (fasted/normal/high fat) and Proton Pump Inhibitor (PPI) co-administration for a selected formulation; as well as a formulation containing DNX HBr in the monohydrate state (Part B). RESULTS: TIM-1 data showed that the fed state bioaccessibility of DNX was significantly decreased compared to the fasted state with no significant differences between formulations. Dosed with normal/high fat food the selected formulation showed comparable exposure and a modest increase in DNX systemic PK was observed with PPI dependent on meal type. Under fed conditions DNX systemic exposure was comparable for the monohydrate and hemihydrate formulations. The integration of biorelevant TIM-1 data into the PBPK model led to the successful simulation of a DNX negative food effect. CONCLUSIONS: Interactions between DNX and food components are the likely the source of the negative food effect via micellar entrapment, ion pairing and/or meal induced viscosity changes.

Translation of Inhaled Drug Optimization Strategies into Clinical Pharmacokinetics and Pharmacodynamics Using GSK2292767A, a Novel Inhaled Phosphoinositide 3-Kinase δ Inhibitor.

This study describes the pharmacokinetic (PK) and pharmaco-dynamic (PD) profile of N-(5-(4-(5-(((2R,6S)-2,6-dimethylmorpholino)methyl)oxazol-2-yl)-1H-indazol-6-yl)-2-methoxypyridin-3-yl)methanesulfonamide (GSK2292767A), a novel low-solubility inhaled phosphoinositide 3-kinase delta (PI3Kδ) inhibitor developed as an alternative to 2-(6-(1H-indol-4-yl)-1H-indazol-4-yl)-5-((4-isopropylpiperazin-1-yl)methyl)oxazole (nemiralisib), which is a highly soluble inhaled inhibitor of PI3Kδ with a lung profile consistent with once-daily dosing. GSK2292767A has a similar in vitro cellular profile to nemiralisib and reduces eosinophilia in a murine PD model by 63% (n = 5, P < 0.05). To explore whether a low-soluble compound results in effective PI3Kδ inhibition in humans, a first time in human study was conducted with GSK2292767A in healthy volunteers who smoke. GSK2292767A was generally well tolerated, with headache being the most common reported adverse event. PD changes in induced sputum were measured in combination with drug concentrations in plasma from single (0.05-2 mg, n = 37), and 14-day repeat (2 mg, n = 12) doses of GSK2292767A. Trough bronchoalveolar lavage (BAL) for PK was taken after 14 days of repeat dosing. GSK2292767A displayed a linear increase in plasma exposure with dose, with marginal accumulation after 14 days. Induced sputum showed a 27% (90% confidence interval 15%, 37%) reduction in phosphatidylinositol-trisphosphate (the product of phosphoinositide 3-kinase activation) 3 hours after a single dose. Reduction was not maintained 24 hours after single or repeat dosing. BAL analysis confirmed the presence of GSK2292767A in lung at 24 hours, consistent with the preclinical lung retention profile. Despite good lung retention, target engagement was only present at 3 hours. This exposure-response disconnect is an important observation for future inhaled drug design strategies considering low solubility to drive lung retention.