Self-emulsifying drug delivery systems (SEDDS) represent an innovative approach to improving the solubility and bioavailability of poorly water-soluble drugs, addressing significant challenges associated with oral drug delivery. This review highlights the advancements and applications of SEDDS, including their transition from liquid to solid forms, while addressing the formulation strategies, characterization techniques, and future prospects in pharmaceutical sciences. The review systematically analyzes existing studies on SEDDS, focusing on their classification into liquid and solid forms and their preparation methods, including spray drying, hot-melt extrusion, and adsorption onto carriers. Characterization techniques such as droplet size analysis, dissolution studies, and solid-state evaluations are detailed. Additionally, emerging trends, including 3D printing, hybrid systems, and supersaturable SEDDS (Su-SEDDS), are explored. Liquid SEDDS (L-SEDDS) enhance drug solubility and absorption by forming emulsions upon contact with gastrointestinal fluids. However, they suffer from stability and leakage issues. Transitioning to solid SEDDS (S-SEDDS) has resolved these limitations, offering enhanced stability, scalability, and patient compliance. Innovations such as personalized 3D-printed SEDDS, biologics delivery, and targeted systems demonstrate their potential for diverse therapeutic applications. Computational modeling and in silico approaches further accelerate formulation optimization. SEDDS have revolutionized drug delivery by improving bioavailability and enabling precise, patient-centric therapies. While challenges such as scalability and excipient toxicity persist, emerging technologies and multidisciplinary collaborations are paving the way for next-generation SEDDS. Their adaptability and potential for personalized medicine solidify their role as a cornerstone in modern pharmaceutical development.

Quetiapine fumarate (QTF) was approved for the treatment of schizophrenia and acute manic episodes. QTF can also be used as an adjunctive treatment for major depressive disorders. QTF oral bioavailability is limited due to its poor aqueous solubility and pre-systemic metabolism. The objective of the current investigation was the formulation development and manufacturing of solid self-nanoemulsifying drug delivery system (S-SNEDDS) formulation through a single-step continuous hot-melt extrusion (HME) process to address these drawbacks. In this study, Capmul^® MCM, Gelucire^® 48/16, and propylene glycol were selected as oil, surfactant, and co-surfactant, respectively, for the preparation of S-SNEDDS. Soluplus^® and Klucel™ EF (1:1) were selected as the solid carrier. Response surface methodology in the form of central composite design (CCD) was utilized in the current experimental design to develop the S-SNEDDS formulations via a continuous HME technology. The developed formulations were evaluated for self-emulsifying properties, particle size distribution, thermal behavior, crystallinity, morphology, physicochemical incompatibility, accelerated stability, and in vitro drug release studies. The globule size and emulsification time of the optimized SNEDDS formulation was 92.27 ± 3.4 nm and 3.4 ± 3.38 min. The differential scanning calorimetry (DSC) and powder X-ray diffraction (PXRD) studies revealed the amorphous nature of the drug within the formulation. There were no drug-excipient incompatibilities observed following the Fourier transform infrared (FTIR) spectroscopy. The optimized formulation showed an extended-release profile for 24 h. The optimized formulation was stable for three months (last time-point tested) at 40 °C/75% RH. Therefore, the developed S-SNEDDS formulation could be an effective oral delivery platform for QTF and could lead to better therapeutic outcomes.

Background/Objectives: This study evaluates the efficacy of twin screw melt granulation (TSMG), and hot-melt extrusion (HME) techniques in enhancing the solubility and dissolution of simvastatin (SIM), a poorly water-soluble drug with low bioavailability. Additionally, the study explores the impact of binary polymer blends on the drug’s miscibility, solubility, and in vitro release profile. Methods: SIM was processed with various polymeric combinations at a 30% w/w drug load, and a 1:1 ratio of binary polymer blends, including Soluplus^® (SOP), Kollidon^® K12 (K12), Kollidon^® VA64 (KVA), and Kollicoat^® IR (KIR). The solid dispersions were characterized using modulated differential scanning calorimetry (M-DSC), powder X-ray diffraction (PXRD), and Fourier-transform infrared spectroscopy (FTIR). Dissolution studies compared the developed formulations against a marketed product. Results: The SIM-SOP/KIR blend showed the highest solubility (34 µg/mL), achieving an approximately 5.5-fold enhancement over the pure drug. Dissolution studies showed that SIM-SOP/KIR formulations had significantly higher release profiles than the physical mixture (PM) and pure drug (p < 0.01). Additionally, their release was similar to a marketed formulation, with 100% drug release within 30 min. In contrast, the SIM-K12/KIR formulation exhibited strong miscibility, but limited solubility and slower release rates, suggesting that high miscibility does not necessarily correlate with improved solubility. Conclusions: This study demonstrates the effectiveness of TSMG, and HME as effective continuous manufacturing technologies for improving the therapeutic efficacy of poorly water-soluble drugs. It also emphasizes the complexity of polymer–drug interactions and the necessity of carefully selecting compatible polymers to optimize the quality and performance of pharmaceutical formulations.

Background/Objectives: This study aimed to develop and evaluate taste-masked theophylline pellets using hot-melt extrusion (HME) technology. Additionally, the study evaluates the efficacy of various taste-masking polymers by comparing three pH-dependent polymers, Kollicoat^® Smartseal 100P, Eudragit^® EPO, and Kollicoat^® MAE 100-55, in masking taste and optimizing drug release. Methods: Formulations were designed with varying drug loads (10%, 20%, and 30%) and plasticizer concentrations (20% and 30% PEG 1500). Lead formulations were characterized using differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), bitter threshold level, and in vitro release testing. Stability was assessed under accelerated conditions (40 °C ± 2 °C and 75% ± 5% RH) for three months. Results: DSC confirmed homogenous dispersion of the drug within the polymer matrix. The optimized formulation comprising 20% theophylline, 20% PEG 1500, and 60% Kollicoat^® Smartseal 100P demonstrated effective taste masking, releasing only 1.1% of the drug in simulated salivary fluid (SSF) within two minutes, significantly lower than the pure drug (29.5%, p < 0.05), Kollicoat^® MAE 100-55 (2.8%, p < 0.05), and comparable to Eudragit^® EPO (2.1%, p > 0.05). Solubility studies further confirmed that theophylline release from the lead formulations remained well below its reported bitter threshold, which could prevent taste perception and mitigate bitterness. In gastric fluid, complete drug release was achieved from Kollicoat^® Smartseal 100P and Eudragit^® EPO, while Kollicoat^® MAE 100-55 exhibited limited release. Stability studies showed that the Kollicoat^® Smartseal 100P formulation maintained its texture, taste-masking efficacy, and dissolution profile under accelerated conditions. Conclusions: The study demonstrates the novel exploration of Kollicoat^® Smartseal 100P for HME application, and its effectiveness in achieving robust taste masking for theophylline, improving patient compliance, particularly in pediatric and geriatric populations.

Background/Objectives: This study aimed to develop a novel amorphous solid dispersion (ASD) platform using poly(2-ethyl-2-oxazoline) (PEtOx) for the solubility enhancement of poorly water-soluble drugs. Fenofibrate (FB), a Biopharmaceutics Classification System (BCS) Class II drug, was selected as the model drug. The novelty of this work lies in the formulation of dual-matrix systems by blending PEtOx of varying molecular weights (50 kDa, 200 kDa, 500 kDa) with solubility-enhancing polymers, Soluplus^® and Kollidon^® VA64, to investigate component compatibility, synergistic solubility enhancement, and the influence of PEtOx molecular weight on drug release. Methods: ASDs were prepared via hot-melt extrusion (HME) and characterized using differential scanning calorimetry (DSC), scanning electron microscopy (SEM), powder X-ray diffraction (PXRD), and Fourier transform–infrared spectroscopy (FTIR) to confirm FB amorphization and evaluate drug–polymer interactions. In vitro dissolution testing was performed to assess drug release performance, and stability studies were conducted at ambient conditions for one month to evaluate physical stability. Results: DSC, PXRD, and FTIR confirmed the successful amorphization of FB and good miscibility between PEtOx and the selected excipients. In vitro dissolution studies showed an 8–12-fold increase in FB release from ASDs compared to crystalline drug. Lower-molecular-weight PEtOx grades yielded faster release profiles, while binary blends with Soluplus^® or Kollidon^® VA64 enabled tailored drug release. Stability testing indicated that all formulations maintained their amorphous state over one month. Conclusions: PEtOx-based ASDs represent a versatile platform for enhancing the solubility and dissolution of poorly water-soluble drugs. By adjusting polymer molecular weight and combining with complementary excipients, release profiles can be optimized to achieve improved performance and stability.