Optimization of self-microemulsifying drug delivery system for phospholipid complex of telmisartan using D-optimal mixture design

Solid Self-Microemulsifying Drug Delivery System for Improved Oral Bioavailability of Relugolix: Preparation and Evaluation

Purpose

To improve the oral absorption of relugolix (RLGL), which has low oral bioavailability due to its low solubility and being a substrate of P-glycoprotein (P-gp). A solid self-microemulsifying drug delivery system of relugolix (RLGL-S-SMEDDS) was prepared and evaluated in vitro and in vivo.

Methods

The composition of the solid self-microemulsifying drug delivery system (S-SMEDDS) was selected by solubility study and pseudo-ternary phase diagram, and further optimized by Design-Expert optimization design. The optimized RLGL-S-SMEDDS were evaluated in terms of particle size, zeta potential, morphology analysis, thermodynamic stability, drug release, flow properties, transporter pathways in Caco-2 cells, the influence of excipients on the intestinal transporters, transport within Caco-2 cell monolayers and transport in lymphocyte. In vivo pharmacokinetic study and toxicological study were also conducted.

Results

The optimum formulation for self-microemulsifying drug delivery system (SMEDDS) consists of Ethyl Oleate (26% of the weight), Solutol HS15 (49% of the weight), Transcutol HP (25% of the weight) and loaded relugolix (4.8 mg/g). The S-SMEDDS was then formed by adsorbing 2.4 g of SMEDDS onto 1 g of hydrophilic-200 silica. In phosphate buffered saline (PBS) (pH 6.8) release medium containing 1% tween 80, the vitro release studies showed 86% cumulative drug release for RLGL-S-SMEDDS and 3.6% cumulative drug release for RLGL suspensions. In vitro cellular uptake experiments revealed that the uptake of RLGL-S-SMEDDS by Caco-2 cells was three times higher than that of free RLGL, and that S-SMEDDS can enhance the drug absorption through lymphatic absorption and inhibition of intestinal transporter. In vivo pharmacokinetic evaluation demonstrated that the oral bioavailability of RLGL-S-SMEDDS was 1.9 times higher than that of RLGL-suspensions. There was no apparent cardiac, hepatic, splenic, pulmonary or renal toxicity on the surface discovered by pathological analysis after oral administration.

Conclusion

It is evident that S-SMEDDS may be a safe and effective method to improve oral absorption of drugs with low oral bioavailability.

Valsartan Loaded Solid Self-Nanoemulsifying Delivery System to Enhance Oral Absorption and Bioavailability

Valsartan (VST) is an angiotensin II receptor antagonist with low oral bioavailability. The present study developed a solid self-nanoemulsifying drug delivery system (S-SNEDDS) to enhance the oral absorption and bioavailability of VST. VST-loaded liquid SNEDDS (VST@L-SNEDDS) was prepared by investigating the solubility of VST and constructing the pseudo-ternary phase diagrams. The formulation of VST@S-SNEDDS was obtained by adsorbing VST@L-SNEDDS onto a solid carrier. In vitro studies including drug dissolution, stability, cytotoxicity, and Caco-2 uptake of VST@S-SNEDDS were assessed. An in vivo pharmacokinetic study of VST@S-SNEDDS was employed to evaluate the oral bioavailability of VST. VST@L-SNEDDS, with an average particle size of 19.90 nm and zeta potential of -20.57 mV, consisted of 12.37% VST (drug loading), 21.91% ethyl oleate, 45.50% RH 40, and 20.22% Transcutol HP. VST@S-SNEDDS was prepared using Neusilin® UFL2 as a solid adsorbent, which contained VST@L-SNEDDS at 2.28 ± 0.15 g/g. The in vitro release study demonstrated that VST@S-SNEDDS exhibited rapid release characteristic without affecting by the pH of the media, and dissolution rates exceeded 90% within 60 min in different media. The long-term stability of VST@S-SNEDDS was better than that of VST@L-SNEDDS. These two formulations increased the Caco-2 uptake significantly. The area under the drug concentration-time curve (AUC0-24h) and peak drug concentration in plasma (Cmax) of VST@S-SNEDDS increased by 2.28-fold and 4.86-fold compared to raw VST, respectively. The proposed VST@S-SNEDDS represents a novel approach to enhance the oral absorption and bioavailability of VST, providing a promising avenue for hypertension treatment.

A cochleate formulation optimized by D-optimal mixture design enhances oral bioavailability of Revaprazan

A cochleate formulation was developed to enhance the oral bioavailability of revaprazan (RVP). Dimyristoyl phosphatidylcholine (DMPC) liposome containing dicetyl phosphate (DCP) successfully formed a cochleate after treatment with CaCl2, whereas that containing sodium deoxycholate did not. Cochleate was optimised using a D-optimal mixture design with three independent variables-DMPC (X1, 70.58 mol%), cholesterol (X2, 22.54 mol%), and DCP (X3, 6.88 mol%)-and three response variables: encapsulation efficiency (Y1, 76.92%), released amount of free fatty acid at 2 h (Y2, 39.82%), and released amount of RVP at 6 h (Y3, 73.72%). The desirability function was 0.616, showing an excellent agreement between the predicted and experimental values. The cylindrical morphology of the optimised cochleate was visualised, and laurdan spectroscopy confirmed the dehydrated membrane interface, showing an increased generalised polarisation value (approximately 0.5) over small unilamellar vesicle of RVP (RVP-SUV; approximately 0.1). The optimised cochleate showed greater resistance to pancreatic enzyme than RVP-SUV. RVP was released in a controlled manner, achieving approximately 94% release in 12 h. Following oral administration in rats, the optimised cochleate improved the relative bioavailability of RVP by approximately 274%, 255%, and 172% compared to RVP suspension, a physical mixture of RVP and the cochleate, and RVP-SUV, respectively. Thus, the optimised cochleate formulation might be a good candidate for the practical development of RVP.

Lipid Horizons: Recent Advances and Future Prospects in LBDDS for Oral Administration of Antihypertensive Agents

The lipid-based drug delivery system (LBDDS) is a well-established technique that is anticipated to bring about comprehensive transformations in the pharmaceutical field, impacting the management and administration of drugs, as well as treatment and diagnosis. Various LBDDSs verified to be an efficacious mechanism for monitoring hypertension systems are SEDDS (self-nano emulsifying drug delivery), nanoemulsion, microemulsions, vesicular systems (transferosomes and liposomes), and solid lipid nanoparticles. LBDDSs overcome the shortcomings that are associated with antihypertensive agents because around fifty percent of the antihypertensive agents experience a few drawbacks including short half-life because of hepatic first-pass metabolism, poor aqueous solubility, low permeation rate, and undesirable side effects. This review emphasizes antihypertensive agents that were encapsulated into the lipid carrier to improve their poor oral bioavailability. Incorporating cutting-edge technologies such as nanotechnology and targeted drug delivery, LBDDS holds promise in addressing the multifactorial nature of hypertension. By fine-tuning drug release profiles and enhancing drug uptake at specific sites, LBDDS can potentially target renin-angiotensin-aldosterone system components, sympathetic nervous system pathways, and endothelial dysfunction, all of which play crucial roles in hypertension pathophysiology. The future of hypertension management using LBDDS is promising, with ongoing reviews focusing on precision medicine approaches, improved biocompatibility, and reduced toxicity. As we delve deeper into understanding the intricate mechanisms underlying hypertension, LBDDS offers a pathway to develop next-generation antihypertensive therapies that are safer, more effective, and tailored to individual patient needs.

Design and Evaluation of Ginkgolides Gastric Floating Controlled Release Tablets Based on Solid Supersaturated Self-nanoemulsifying

Ginkgolides are receptor antagonist of platelet activating factor with great clinical prospect, but its application is limited by its low solubility, short half-life and poor alkaline environment stability. It is difficult to solve these problems with a single drug delivery system. In this study, supersaturated self-nanoemulsifying gastric floating tablets of ginkgolides were developed through the combination of solid supersaturated self-nanoemulsifying drug delivery system (solid S-SNEDDS) and gastric retentive floating drug delivery system (GFDDS) to solve these problems of ginkgolides. Solid S-SNEDDS was prepared by D-optimal mixture design, normalization method and single factor experiment. The properties of solid-S-SNEDDS were studied by TEM, PXRD, FT-IR, SEM and in vitro drug release profile. Then, the optimal formulation of stomach floating tablet was obtained through single factor experiment and center composite design, followed by the study of in vitro release, model and mechanism of release, in vitro buoyancy and kinetics of erosion and swelling. PXRD and FT-IR showed that the drug in solid S-SNEDDS existed in an amorphous manner and formed hydrogen bond with excipients. The results showed that the cumulative release of GA and GB in the optimal tablets was 96.12% and 92.57% higher than the simple tablets within 12 h. The release mechanism of the tablet was skeleton erosion and drug diffusion. In 12 h, the optimal tablets can float stably in vitro and release the drug at a constant rate, with a cumulative release of more than 80%. In summary, the combination of SNEDDS and GFDDS is a promising means to solve the problems of ginkgolides.

Quality by Design-Based Development of Solid Self-Emulsifying Drug Delivery System (SEDDS) as a Potential Carrier for Oral Delivery of Lysozyme

For many years, researchers have been making efforts to find a manufacturing technique, as well as a drug delivery system, that will allow for oral delivery of biopharmaceuticals to their target site of action without impairing their biological activity. Due to the positive in vivo outcomes of this formulation strategy, self-emulsifying drug delivery systems (SEDDSs) have been intensively studied in the last few years as a way of overcoming the different challenges associated with the oral delivery of macromolecules. The purpose of the present study was to examine the possibility of developing solid SEDDSs as potential carriers for the oral delivery of lysozyme (LYS) using the Quality by Design (QbD) concept. LYS was successfully ion paired with anionic surfactant, sodium dodecyl sulphate (SDS), and this complex was incorporated into a previously developed and optimized liquid SEDDS formulation comprising medium-chain triglycerides, polysorbate 80, and PEG 400. The final formulation of a liquid SEDDS carrying the LYS:SDS complex showed satisfactory in vitro characteristics as well as self-emulsifying properties (droplet size: 13.02 nm, PDI: 0.245, and zeta potential: -4.85 mV). The obtained nanoemulsions were robust to dilution in the different media and highly stable after 7 days, with a minor increase in droplet size (13.84 nm) and constant negative zeta potential (-0.49 mV). An optimized liquid SEDDS loaded with the LYS:SDS complex was further solidified into powders by adsorption onto a chosen solid carrier, followed by direct compression into self-emulsifying tablets. Solid SEDDS formulations also exhibited acceptable in vitro characteristics, while LYS preserved its therapeutic activity in all phases of the development process. On the basis of the results gathered, loading the hydrophobic ion pairs of therapeutic proteins and peptides to solid SEDDS may serve as a potential method for delivering biopharmaceuticals orally.

Application of Design of Experiments in the Development of Self-Microemulsifying Drug Delivery Systems

Oral delivery has become the route of choice among all other types of drug administrations. However, typical chronic disease drugs are often poorly water-soluble, have low dissolution rates, and undergo first-pass metabolism, ultimately leading to low bioavailability and lack of efficacy. The lipid-based formulation offers tremendous benefits of using versatile excipients and has great compatibility with all types of dosage forms. Self-microemulsifying drug delivery system (SMEDDS) promotes drug self-emulsification in a combination of oil, surfactant, and co-surfactant, thereby facilitating better drug solubility and absorption. The feasible preparation of SMEDDS creates a promising strategy to improve the drawbacks of lipophilic drugs administered orally. Selecting a decent mixing among these components is, therefore, of importance for successful SMEDDS. Quality by Design (QbD) brings a systematic approach to drug development, and it offers promise to significantly improve the manufacturing quality performance of SMEDDS. Furthermore, it could be benefited efficiently by conducting pre-formulation studies integrated with the statistical design of experiment (DoE). In this review, we highlight the recent findings for the development of microemulsions and SMEDDS by using DoE methods to optimize the formulations for drugs in different excipients with controllable ratios. A brief overview of DoE concepts is discussed, along with its technical benefits in improving SMEDDS formulations.

Enhanced oral absorption of insulin: hydrophobic ion pairing and a self-microemulsifying drug delivery system using a D-optimal mixture design

The lipophilicity of a peptide drug can be considerably increased by hydrophobic ion pairing with amphiphilic counterions for successful incorporation into lipid-based formulations. Herein, to enhance the oral absorption of insulin (INS), a self-microemulsifying drug delivery system (SMEDDS) formulation was developed. Prior to optimization, INS was complexed with sodium n-octadecyl sulfate (SOS) to increase the loading into the SMEDDS. The INS–SOS complex was characterized via scanning electron microscopy, Fourier transform infrared spectroscopy, differential scanning calorimetry, and its dissociation behavior. The SMEDDS was optimized using a D-optimal mixture design with three independent variables including Capmul MCM (X₁, 9.31%), Labrasol (X₂, 49.77%), and Tetraglycol (X₃, 40.92%) and three response variables including droplet size (Y₁, 115.2 nm), INS stability (Y₂, 46.75%), and INS leakage (Y₃, 17.67%). The desirability function was 0.766, indicating excellent agreement between the predicted and experimental values. The stability of INS-SOS against gastrointestinal enzymes was noticeably improved in the SMEDDS, and the majority of INS remained in oil droplets during release. Following oral administration in diabetic rats, the optimized SMEDDS resulted in pharmacological availabilities of 3.23% (50 IU/kg) and 2.13% (100 IU/kg). Thus, the optimized SMEDDS is a good candidate for the practical development of oral delivery of peptide drugs such as INS.

Recent Applications of Mixture Designs in Beverages, Foods, and Pharmaceutical Health: A Systematic Review and Meta-Analysis

Design of Experiments (DoE) is a statistical tool used to plan and optimize experiments and is seen as a quality technology to achieve products excellence. Among the experimental designs (EDs), the mixture designs (MDs) stand out, being widely applied to improve conditions for processing, developing, or formulating novel products. This review aims to provide useful updated information on the capacity and diversity of MDs applications for the industry and scientific community in the areas of food, beverage, and pharmaceutical health. Recent works were selected following the Preferred Reporting Items for Systematic Review and Meta-Analyses statement (PRISMA) flow diagram. Data analysis was performed by self-organizing map (SOM) to check and understand which fields of application/countries/continents are using MDs. Overall, the SOM indicated that Brazil presented the largest number of works using MDs. Among the continents, America and Asia showed a predominance in applications with the same amount of work. Comparing the MDs application areas, the analysis indicated that works are prevalent in food and beverage science in the American continent, while in Asia, health science prevails. MDs were more used to develop functional/nutraceutical products and the formulation of drugs for several diseases. However, we briefly describe some promising research fields in that MDs can still be employed.

Optimization of Thymoquinone-Loaded Self-Nanoemulsion for Management of Indomethacin-Induced Ulcer

To improve the water solubility of thymoquinone (TQ), a major constituent of Nigella sativa seed oil, a TQ-loaded self-nanoemulsifying drug delivery system (SNEDDS) was prepared. The SNEDDS formulation was optimized using almond oil (AO) (Oil; X1), tween 80 (surfactant; X2) and polyethylene glycol 200 (PEG 200) (cosurfactant; X3) compounds as independent variables. The results showed that the globule size ranged from 65 to 320 nm. In addition, a strong agreement was reached between the system estimation and the experimental values of globule size. To evaluate the gastroprotective effect of optimized TQ-loaded SNEDDS against indomethacin (Indo.)-induced gastric ulcers in comparison with non-emulsified TQ, the ulcer index and histopathological changes were estimated. Optimized TQ-loaded SNEDDS showed improved gastroprotective activity against Indo.-induced ulcers relative to the non-emulsified TQ. In addition, the gastroprotective index was improved by 2-fold in TQ-loaded SNEDDS as compared to non-emulsified TQ. This is attributed to the strong antioxidant and the cytoprotective activities of the TQ. These results demonstrate enhancement of the efficacy of TQ through the optimized SNEDDS.

Tailoring immediate release FDM 3D printed tablets using a quality by design (QbD) approach

The aims of this work were to produce immediate release printed tablets using fused deposition modelling (FDM) technique and to systematically explore the effects of different compositions on drug release by Quality by Design approach. Screening studies of various drug loadings and excipients were conducted by hot melt extrusion and FDM printing to set up the appropriate limit of each independent factor (critical material attribute, CMA) in Design of Experiment. This study demonstrated that the use of polymeric mixture containing different theophylline loadings (10, 30 and 60% w/w) in combination with multiple pharmaceutical polymers (hydroxy propyl cellulose (HPC), Eudragit® EPO, Kollidon® VA 64) and disintegrant (sodium starch glycolate) were successfully hot melt-extruded and FDM printed with no plasticizer. Rheological measurement was performed to understand the critical process parameters (CPP) while the mechanical property of extrudable and printable filaments was investigated by 3-point test for the formulation development. Surprisingly, HPC were found to be superior as a flexibility modifier in all printable filaments. A range of pharmaceutical characterizations were examined to ensure the critical quality attributes (CQA). Characteristic dissolution profiles were obtained. D-optimal mixture design of 17 formulations suggested that theophylline release was considerably affected by the combined action of different excipients and could predict the optimum formulation with the required quality target product profile (QTPP) in pharmacopoeia (85% release at 30 min). Therefore, this can be a useful platform to develop immediate release products for a specific group of patients commercially.

Improved Pharmacodynamic Potential of Rosuvastatin by Self-Nanoemulsifying Drug Delivery System: An in vitro and in vivo Evaluation

PURPOSE

The purpose of this proposed research was to investigate a nano-formulation developed using self-nanoemulsifying drug delivery system (SNEDDS) to improve the pharmacodynamic potential of rosuvastatin by assisting its transportation through lymphatic circulation.

METHODS

The utilized lipids, surfactants, and co-surfactants for SNEDDS were selected on the basis of solubility studies. The SNEDDS formulation was optimized by implementing a D-optimal mixture design, wherein the effect of concentration of Capmul MCM EP (X1), Tween 20 (X2) and Transcutol P (X3) as independent variables was studied on droplet size (Y1), % cumulative drug release (Y2) and self-emulsification time (Y3) as dependent variables. The optimized formulation was evaluated via in vitro parameters and in vivo pharmacodynamic potential in Wistar rats.

RESULTS

The D-optimal mixture design and subsequent ANOVA application resulted in the assortment of the optimized SNEDDS formulation that exhibited a droplet size of nano range (14.91nm), in vitro drug release of >90% within 30 minutes, and self-emulsification time of 16 seconds. The in vivo pharmacodynamic study carried out using Wistar rats confirmed the better antihyperlipidemic potential of developed formulation in normalizing the lipidic level of serum in contrast to pure drug and marketed tablets.

CONCLUSION

This research reports the application of D-optimal mixture design for successful and systematic development of rosuvastatin-loaded SNEDDS with distinctly enhanced in vitro and in vivo performance in comparison to marketed formulation. Eventually, improved anti-hyperlipidemic efficacy was envisaged which might be attributed to increased drug solubility and absorption. Overall, this study shows the utility of SNEDDS for improving the dissolution rate and bioavailability of poor aqueous-soluble drugs. The present SNEDDS formulation could be a promising approach and alternative to conventional dosage form.

Design and optimization of candesartan loaded self-nanoemulsifying drug delivery system for improving its dissolution rate and pharmacodynamic potential

During the last decades, much attention has been focused on SNEDDS approach to resolve concerns of BCS II class drugs with accentuation on upgrading the solubility and bioavailability. The present hypothesis confirms the theory that SNEDDS can reduce the impact of food on Candesartan solubilization, thereby offering the potential for improved oral delivery without co-administration with meals. The present studies describe quality-by-design-based development and characterization of Candesartan loaded SNEDDS for improving its pharmacodynamic potential. D-optimal mixture design was used for systematic optimization of SNEDDS, which showed globule size of 13.91 nm, more rapid drug release rate of >90% in 30 min and 16 s for self-emulsification. The optimized formulations were extensively evaluated, where an in vitro drug release study indicated up to 1.99- and 1.10-fold enhancement in dissolution rate from SNEDDS over pure drug and marketed tablet. In vivo pharmacodynamic investigation also showed superior antihypertensive potential of SNEDDS in normalizing serum lipid levels as compared to pure drug and marketed tablet that was executed on male Wistar rats. Overall, this paper reports successful systematic development of candesartan-loaded SNEDDS with distinctly improved biopharmaceutical performance. This research work interpreted a major role of SNEDDS for enhancing the rate of dissolution and bioavailability of poorly water soluble drugs.

Supersaturable self-microemulsifying drug delivery system enhances dissolution and bioavailability of telmisartan

To enhance the dissolution and oral bioavailability of telmisartan (TMS), a poorly water-soluble anti-hypertensive drug, a supersaturable self-microemulsifying drug delivery system (SuSMEDDS) was developed. Amorphous alkalinized TMS (AAT) was formulated into a SMEDDS, composed of Capmul® MCM (oil), Cremophor^® RH40 (surfactant), and tetraglycol (co-surfactant). Although the SMEDDS was rapidly dissolved (>80% within 5 min) in a limited condition (500 mL, pH 6.8), drug precipitation was observed over time, resulting in a decrease in dissolution levels. The precipitation was due to drug recrystallization, as determined by differential scanning calorimetry and powder X-ray diffraction analyses. Several polymers, including Soluplus^® (SOL), were screened as precipitation inhibitors; ultimately, SuSMEDDS-SOL was prepared by admixing SOL and the SMEDDS at a 5:100 (w/w) ratio. SuSMEDDS-SOL was superior in terms of dissolution efficiency (>90% over 2 h) and dissolution-retaining time (no precipitation over 2 h). An in vivo pharmacokinetic study in rats revealed that the oral bioavailability of SuSMEDDS-SOL was 4.8-, 1.3-, and 1.2-fold greater than those of the TMS suspension, AAT solution, and SMEDDS, respectively. Therefore, SuSMEDDS-SOL is a promising candidate to enhance the dissolution and oral bioavailability of TMS.

Development and Evaluation of Docetaxel-Phospholipid Complex Loaded Self-Microemulsifying Drug Delivery System: Optimization and In Vitro/Ex Vivo Studies

Docetaxel (DTX) has clinical efficacy in the treatment of breast cancer, but it is difficult to develop a product for oral administration, due to low solubility and permeability. This study focused on preparing a self-microemulsifying drug delivery system (SME) loaded with DTX-phospholipid complex (DTX@PLC), to improve the dissolution and gastrointestinal (GI) permeability of DTX. A dual technique combining the phospholipid complexation and SME formulation described as improving upon the disadvantages of DTX has been proposed. We hypothesized that the complexation of DTX with phospholipids can improve the lipophilicity of DTX, thereby increasing the affinity of the drug to the cell lipid membrane, and simultaneously improving permeability through the GI barrier. Meanwhile, DTX@PLC-loaded SME (DTX@PLC-SME) increases the dissolution and surface area of DTX by forming a microemulsion in the intestinal fluid, providing sufficient opportunity for the drug to contact the GI membrane. First, we prepared DTX@PLC-SME by combining dual technologies, which are advantages for oral absorption. Next, we optimized DTX@PLC-SME with nanosized droplets (117.1 nm), low precipitation (8.9%), and high solubility (33.0 mg/g), which formed a homogeneous microemulsion in the aqueous phase. Dissolution and cellular uptake studies demonstrated that DTX@PLC-SME showed 5.6-fold higher dissolution and 2.3-fold higher DTX uptake in Caco-2 cells than raw material. In addition, an ex vivo gut sac study confirmed that DTX@PLC-SME improved GI permeability of DTX by 2.6-fold compared to raw material. These results suggested that DTX@PLC-SME can significantly overcome the disadvantages of anticancer agents, such as low solubility and permeability.