Estimating the Oral Absorption from Self-Nanoemulsifying Drug Delivery Systems Using an In Vitro Lipolysis-Permeation Method

The aim of this study was to design an in vitro lipolysis-permeation method to estimate drug absorption following the oral administration of self-nanoemulsifying drug delivery systems (SNEDDSs). The method was evaluated by testing five oral formulations containing cinnarizine (four SNEDDSs and one aqueous suspension) from a previously published pharmacokinetic study in rats. In that study, the pharmacokinetic profiles of the five formulations did not correlate with the drug solubilization profiles obtained during in vitro intestinal lipolysis. Using the designed lipolysis-permeation method, in vitro lipolysis of the five formulations was followed by in vitro drug permeation in Franz diffusion cells equipped with PermeaPad® barriers. A linear in vivo–in vitro correlation was obtained when comparing the area under the in vitro drug permeation–time curve (AUC0–3h), to the AUC0–3h of the plasma concentration–time profile obtained from the in vivo study. Based on these results, the evaluated lipolysis-permeation method was found to be a promising tool for estimating the in vivo performance of SNEDDSs, but more studies are needed to evaluate the method further.

The impact of emulsion droplet size on in vitro lipolysis rate and in vivo plasma uptake kinetics of triglycerides and vitamin D3 in rats

Emulsions with smaller droplets are more rapidly lipolyzed in the intestine, resulting in increased uptake to plasma of triglycerides. However, the uptake of vitamin D3 from the same emulsions is not significantly affected by droplet size.

Role of Biorelevant Media in Estimation of in vitro Lipolysis and Food Impact on Self-emulsifying Drug Delivery Systems.

: Self-emulsifying drug delivery systems (SEDDS) includes self-micro emulsifying drug delivery system (SMEDDS) and self-nano emulsifying drug delivery system (SNEDDS) whose major benefits is reduction of inter/intra subject variability and food effect which may alter the pharmacological response of the drug. Oral intake of these formulations triggers the digestion process because of pancreatic lipase which emulsify/digest the lipidic ingredients of the formulation resulting into precipitation of the drug. As a tool to foresee in vivo medicament precipitation, in vitro lipolysis models are established. Biorelevant media play an important role to study the effect of in vitro lipolysis and food impact on the bioavailability of SEDDS formulations. It is vital to generate composition of fluids for both fed and fasting conditions of gastric, small intestine and colon to investigate the impact of in vitro lipolysis and food effect on the release behavior of drug from SEDDS. Fed/Fasted state simulated gastric fluid (Fe/FaSSGF), Fed/Fasted state simulated gastric fluid (Fe/FaSSIF) (Phosphate buffers) are first generation while Fa/FeSSIF-V2 (maleate) are second generation biorelevant media utilized for these studies. FaSSIF-V3 belongs to third generation which differs from other generations in the composition and source of bile salts. With updates in physiological data, it is vital to incorporate changes in the dissolution media to make it more biorelevant. This review paper mainly laid emphasis on the compositions of biorelevant media of gastric and small intestine for both fed and fasting conditions. In addition to these, applications of biorelevant to investigate effect of in vitro lipolysis and food on SEDDS are discussed with some recent research reports.

Supersaturated Lipid-Based Formulations to Enhance the Oral Bioavailability of Venetoclax

Increasing numbers of beyond Rule-of-Five drugs are emerging from discovery pipelines, generating a need for bio-enabling formulation approaches, such as lipid-based formulations (LBF), to ensure maximal in vivo exposure. However, many drug candidates display insufficient lipid solubility, leading to dose-loading limitations in LBFs. The aim of this study was to explore the potential of supersaturated LBFs (sLBF) for the beyond Rule-of-Five drug venetoclax. Temperature-induced sLBFs of venetoclax were obtained in olive oil, Captex® 1000, Peceol® and Capmul MCM®, respectively. A Peceol®-based sLBF displayed the highest drug loading and was therefore evaluated further. In vitro lipolysis demonstrated that the Peceol®-based sLBF was able to generate higher venetoclax concentrations in the aqueous phase compared to a Peceol®-based suspension and an aqueous suspension. A subsequent bioavailability study in pigs demonstrated for sLBF a 3.8-fold and 2.1-fold higher bioavailability compared to the drug powder and Peceol®-based suspension, respectively. In conclusion, sLBF is a promising bio-enabling formulation approach to enhance in vivo exposure of beyond Rule-of-Five drugs, such as venetoclax. The in vitro lipolysis results correctly predicted a higher exposure of the sLBF in vivo. The findings of this study are of particular relevance to pre-clinical drug development, where maximum exposure is required.

Hot Melt Coating of Amorphous Carvedilol

The use of amorphous drug delivery systems is an attractive approach to improve the bioavailability of low molecular weight drug candidates that suffer from poor aqueous solubility. However, the pharmaceutical performance of many neat amorphous drugs is compromised by their tendency for recrystallization during storage and lumping upon dissolution, which may be improved by the application of coatings on amorphous surfaces. In this study, hot melt coating (HMC) as a solvent-free coating method was utilized to coat amorphous carvedilol (CRV) particles with tripalmitin containing 10% (w/w) and 20% (w/w) of polysorbate 65 (PS65) in a fluid bed coater. Lipid coated amorphous particles were assessed in terms of their physical stability during storage and their drug release during dynamic in vitro lipolysis. The release of CRV during in vitro lipolysis was shown to be mainly dependent on the PS65 concentration in the coating layer, with a PS65 concentration of 20% (w/w) resulting in an immediate release profile. The physical stability of the amorphous CRV core, however, was negatively affected by the lipid coating, resulting in the recrystallization of CRV at the interface between the crystalline lipid layer and the amorphous drug core. Our study demonstrated the feasibility of lipid spray coating of amorphous CRV as a strategy to modify the drug release from amorphous systems but at the same time highlights the importance of surface-mediated processes for the physical stability of the amorphous form.