Aliskiren Hemifumarate Proliposomes for Improved Oral Drug Delivery: Formulation Development, In Vitro and In Vivo Permeability Testing.

The objective of this study was to develop proliposomal formulations for a poorly bioavailable drug, aliskiren hemifumarate (AKH). A solvent evaporation method was used to prepare proliposomes using different lipids. The lipids of selection were soy phosphatidylcholine (SPC), dimyristoylphosphatidylcholine (DMPC), and dimyristoylphosphatidylglycerol sodium (DMPG Na), stearylamine, and cholesterol in various ratios. Proliposomes were evaluated for particle size, zeta potential, in vitro drug release, in vitro permeability, and in vivo pharmacokinetics upon hydration with aqueous phase. In vitro drug release studies were conducted in 0.01 N hydrochloric acid using USP type II dissolution apparatus. Parallel artificial membrane permeation assay (PAMPA) and Caco-2 cell line models were used to study the in vitro drug permeation. Male Sprague-Dawley (SD) rats were used to conduct in vivo pharmacokinetic studies. Among different formulations, proliposomes with drug/DMPC/cholesterol/stearylamine in the ratio of 1:5:0.025:0.050 (w/w/w/w) demonstrated the desired particle size, higher zeta potential, and higher encapsulation efficiency. The PAMPA and Caco-2 cell line experiments showed a significantly higher permeability of AKH with proliposomes as compared to pure AKH. In animal studies, the optimized formulation of proliposomes showed significant improvement in the rate and extent of absorption of AKH. Specifically, following a single oral administration, the relative bioavailability of AKH proliposome formulation was 230% when compared to pure AKH suspension.

Formulation of Dronedarone Hydrochloride-Loaded Proliposomes: In Vitro and In Vivo Evaluation Using Caco-2 and Rat Model.

The objective of the present study was to develop a proliposomal formulation to increase the oral bioavailability of dronedarone hydrochloride (dronedarone HCl) by enhancing solubility, dissolution, and/or intestinal absorption. Proliposomes were prepared by using solvent evaporation method. In this process, different ratios of drug, phospholipids, such as soy phosphatidylcholine (SPC), Phospholipon 90H, hydrogenated egg phosphatidylcholine (HEPC), and dimyristoyl phosphatidylglycerol (DMPG), and cholesterol were used. Physical characterization and in vitro dissolution studies were evaluated for the prepared formulations. In vitro transport across the membrane was carried out using Caco-2 cells. Among all the formulations, the amount of drug released in dissolution was higher with DPF8 formulation (drug:DMPG Na:cholesterol:::1:2:0.2) compared to the pure drug. Also, Caco-2 cell permeability studies resulted in 2.6-fold increase in apparent permeability. Optimized formulation was evaluated in vivo in male Sprague-Dawley rats. After single oral administration of optimized formulation (DPF8), a relative bioavailability of 148.36% was achieved compared to the pure drug. Improved oral bioavailability of dronedarone could be provided by an optimized proliposomal formulation with enhanced solubility, permeability, and oral absorption.