Study of Valproic Acid Liposomes for Delivery into the Brain through an Intranasal Route

Formulation and characterization of transfersomes for ocular delivery of tonabersat

Transfersomes (TFS) are deformable vesicles, known for their ability to enhance transdermal drug penetration. This study aimed to evaluate whether TFS can also enhance ocular delivery of poorly soluble tonabersat. TFS were prepared using Phospholipon® 90G with Tween® 80 as the edge activator. The effect of formulation parameters (edge activator and cryoprotectant concentrations) on TFS characteristics were evaluated using a full factorial design. The optimized TFS eyedrop was characterized for particle size, zeta potential, deformability, entrapment efficiency (EE), drug content, pH, osmolality and TFS stability over 3 months at different storage conditions. Furthermore, drug penetration into the cornea, conjunctiva, eyelid, and sclera-choroid after topical application was studied ex vivo using a tonabersat solution in medium chain triglycerides as the control. The optimized TFS formed spherical unilamellar vesicles with a mean diameter <130 nm, EE >80%, and were stable at -20 and 5 ± 3 °C for up to 3 months. The TFS eyedrop resulted in significantly greater ocular penetration than the control without affecting the barrier properties of the tested tissues. Drug penetration into different ocular tissues was compared, shedding light on the penetration mechanism of TFS. Overall, this study demonstrates that TFS provide a promising alternative for the ocular delivery of tonabersat.

Intranasal administration of antiseizure drugs using new formulation trends: one step closer to reach clinical trials

INTRODUCTION

Although there are numerous options for epilepsy treatment, its effective control continues unsatisfactory. Thus, search for alternative therapeutic options to improve the efficacy/safety binomial of drugs becomes very attractive to investigate. In this context, intranasal administration of antiseizure drugs formulated on state-of-the-art nanosystems can be a promising strategy.

AREAS COVERED

This work gives a comprehensive overview of different intranasal nanosystems for antiseizure drug administration developed and evaluated on preclinical studies over the last 10 years and published in 'PubMed' and 'Web of Science' databases. Additionally, it highlights their pharmaceutical critical quality attributes and in vivo pharmacological outputs that might infer possible results when transposing to clinical trials.

EXPERT OPINION

Research into optimized nanosystems encapsulating antiseizure drugs to enhance direct nose-to-brain delivery has increased over the last years. Particularly, the interest in formulating first- and second-generation antiseizure drugs in nanoparticles is here highlighted, having demonstrated its in vivo safety and improvement on pharmacokinetic and efficacy outputs. Still, none of them were brought to clinical trials. Thus, considering the existing barriers between preclinical and clinical trials, if supported by robust and targeted quality by design approaches, intranasal drug delivery can be presented as a valid and superior alternative for epilepsy treatment.

Nose-to-brain Drug Delivery System: An Emerging Approach to Chemotherapy-induced Cognitive Impairment

The rise in global cancer burden, notably breast cancer, emphasizes the need to address chemotherapy-induced cognitive impairment, also known as chemobrain. Although chemotherapy drugs are effective against cancer, they can trigger cognitive deficits. This has triggered the exploration of preventive strategies and novel therapeutic approaches. Nanomedicine is evolving as a promising tool to be used for the mitigation of chemobrain by overcoming the blood-brain barrier (BBB) with innovative drug delivery systems. Polymer and lipid-based nanoparticles enable targeted drug release, enhancing therapeutic effectiveness. Utilizing the intranasal route of administration may facilitate drug delivery to the central nervous system (CNS) by circumventing first-pass metabolism. Therefore, knowledge of nasal anatomy is critical for optimizing drug delivery via various pathways. Despite challenges, nanoformulations exhibit the potential in enhancing brain drug delivery. Continuous research into formulation techniques and chemobrain mechanisms is vital for developing effective treatments. The intranasal administration of nanoformulations holds promise for improving therapeutic outcomes in chemobrain management. This review offers insights into potential future research directions, such as exploring novel drug combinations, investigating alternative delivery routes, or integrating emerging technologies to enhance the efficacy and safety of nanoformulations for chemobrain management.

Targeted non-invasive Metformin-Curcumin co-loaded nanohyaluosomes halt osteoarthritis progression and improve articular cartilage structure: A preclinical study

Osteoarthritis (OA) is a degenerative disease that affects the quality of life in elderly and young populations. Current therapies using corticosteroids and non-steroidal anti-inflammatory drugs via parenteral or oral routes show limited ability to retard progression of the disease and achieve long term effectiveness and safety. Herein, the potential of MT-Cur combinatorial nano-formulations in OA management was explored for the first time. MT-Cur loaded nanohyaluosomes (MT-Cur-HL1) were designed for topical administration of the combined therapy in OA. The optimized MT-Cur-HL1 showed particle size 247.7 ± 3.7 nm, zeta potential -37.3 ± 0.4 mV; and entrapment efficiency (%EE) 70.22 %±0.303 and 76.7 %±0.077 for MT and Cur, respectively. MT-Cur-HL1 exhibited sustained drug release over 24 h and were stable over 3 months at 4 °C in terms of P.S., ZP and %EE. A detailed preclinical study, using MIA-induced osteoarthritis rat model, revealed the most significant anti-arthritic effect and halted OA progression of MT-Cur-HL1. This was proved to be mainly through the potentiation of p-AMPK signaling that ultimately led to suppression of its downstream TLR4/ NF-κB signaling pathway with subsequent reduction in MMP13 and ADAMTS5 induced chondrocytes degeneration. This study proved that this trajectory effectively promotes a significant improvement in the articular cartilage structure and reinforcement of joint mobility with an efficient antinociceptive effect. In conclusion, the novel MT-Cur coloaded nanohyaluosomes offer a promising non-invasive approach for the local management of OA.

Technological Strategies Applied to Pharmaceutical Systems for Intranasal Administration of Drugs Intended for Neurological Treatments: A Review

The complexity of treating neurological diseases has meant that new strategies have had to be developed to deliver drugs to the brain more efficiently and safely. Intranasal drug delivery is characterized by its ease of administration, safety, and rapid delivery directly from the nose to the brain. Several strategies have been developed to improve the delivery of drugs to the brain via nasal administration. These include the use of mucoadhesive and thermoresponsive polymers and their combination into polymer blends, as well as the use of liposomes, niosomes, and nano- and microemulsions. Therefore, this review focuses on technologies for developing pharmaceutical systems aimed at delivery via the nose to the brain, contributing to new treatments for difficult neurological disorders. Some of the most common and difficult-to-treat neurological conditions, the intranasal route of administration, and the anatomy of the nasal cavity have been discussed, as well as factors that may influence the absorption of drugs administered into the nose. The types of intranasal formulations and the devices that can be used to administer these products are also discussed in this review. Strategies for improving the transport of bioactive agents and increasing bioavailability are highlighted. The technologies discussed in this review can facilitate the development of formulations with improved properties, such as drug release and mucoadhesiveness, which have several advantages for patients requiring complex neurological treatments.

Design of experiment (DoE) of mucoadhesive valproic acid-loaded nanostructured lipid carriers (NLC) for potential nose-to-brain application

Epilepsy is a highly prevalent neurological disease and valproic acid (VPA) is used as a first-line chronic treatment. However, this drug has poor oral bioavailability, which requires the administration of high doses, resulting in adverse effects. Alternative routes of VPA administration have therefore been investigated, such as the nose-to-brain route, which allows the drug to be transported directly from the nasal cavity to the brain. Here, the use of nanostructured lipid carriers (NLC) to encapsulate drugs administered in the nasal cavity has proved advantageous. The aim of this work was to optimise a mucoadhesive formulation of VPA-loaded NLC for intranasal administration to improve the treatment of epilepsy. The Design of Experiment (DoE) was used to optimise the formulation, starting with component optimisation using Mixture Design (MD), followed by optimisation of the manufacturing process parameters using Central Composite Design (CCD). The optimised VPA-loaded NLC had a particle size of 76.1 ± 2.8 nm, a polydispersity index of 0.190 ± 0.027, a zeta potential of 28.1 ± 2.0 mV and an encapsulation efficiency of 85.4 ± 0.8%. The in vitro release study showed VPA release from the NLC of 50 % after 6 h and 100 % after 24 h. The in vitro biocompatibility experiments in various cell lines have shown that the optimised VPA-loaded NLC formulation is safe up to 75 µg/mL, in neuronal (SH-SY5Y), nasal (RPMI 2650) and hepatic (HepG2) cells. Finally, the interaction of the optimised VPA-loaded NLC formulation with nasal mucus was investigated and mucoadhesive properties were observed. The results of this study suggest that the use of intranasal VPA-loaded NLC may be a promising alternative to promote VPA targeting to the brain, thereby improving bioavailability and minimising adverse effects.

Recent Advances in Intranasal Administration for Brain-Targeting Delivery: A Comprehensive Review of Lipid-Based Nanoparticles and Stimuli-Responsive Gel Formulations

Addressing disorders related to the central nervous system (CNS) remains a complex challenge because of the presence of the blood-brain barrier (BBB), which restricts the entry of external substances into the brain tissue. Consequently, finding ways to overcome the limited therapeutic effect imposed by the BBB has become a central goal in advancing delivery systems targeted to the brain. In this context, the intranasal route has emerged as a promising solution for delivering treatments directly from the nose to the brain through the olfactory and trigeminal nerve pathways and thus, bypassing the BBB. The use of lipid-based nanoparticles, including nano/microemulsions, liposomes, solid lipid nanoparticles, and nanostructured lipid carriers, has shown promise in enhancing the efficiency of nose-to-brain delivery. These nanoparticles facilitate drug absorption from the nasal membrane. Additionally, the in situ gel (ISG) system has gained attention owing to its ability to extend the retention time of administered formulations within the nasal cavity. When combined with lipid-based nanoparticles, the ISG system creates a synergistic effect, further enhancing the overall effectiveness of brain-targeted delivery strategies. This comprehensive review provides a thorough investigation of intranasal administration. It delves into the strengths and limitations of this specific delivery route by considering the anatomical complexities and influential factors that play a role during dosing. Furthermore, this study introduces strategic approaches for incorporating nanoparticles and ISG delivery within the framework of intranasal applications. Finally, the review provides recent information on approved products and the clinical trial status of products related to intranasal administration, along with the inclusion of quality-by-design-related insights.

GastroPlus- and HSPiP-Oriented Predictive Parameters as the Basis of Valproic Acid-Loaded Mucoadhesive Cationic Nanoemulsion Gel for Improved Nose-to-Brain Delivery to Control Convulsion in Humans

Oral and parenteral delivery routes of valproic acid (VA) are associated with serious adverse effects, high hepatic metabolism, high clearance, and low bioavailability in the brain. A GastroPlus program was used to predict in vivo performance of immediate (IR) and sustained release (SR) products in humans. HSPiP software 5.4.08 predicted excipients with maximum possible miscibility of the drug. Based on the GastroPlus and HSPiP program, various excipients were screened for experimental solubility, nanoemulsions, and respective gel studies intended for nasal-to-brain delivery. These were characterized by size, size distribution, polydispersity index, zeta potential, morphology, pH, % transmittance, drug content, and viscosity. In vitro drug release, ex vivo permeation profile (goat nasal mucosa), and penetration studies were conducted. Results showed that in vivo oral drug dissolution and absorption were predicted as 98.6 mg and 18.8 mg, respectively, from both tablets (IR and SR) at 8 h using GastroPlus. The predicted drug access to the portal vein was substantially higher in IR (115 mg) compared to SR (82.6 mg). The plasma drug concentration-time profile predicted was in good agreement with published reports. The program predicted duodenum and jejunum as the prime sites of the drug absorption and no effect of nanonization on Tmax for sustained release formulation. Hansen parameters suggested a suitable selection of excipients. The program recommended nasal-to-brain delivery of the drug using a cationic mucoadhesive nanoemulsion. The optimized CVE6 was associated with the optimal size (113 nm), low PDI (polydispersity index) (0.26), high zeta potential (+34.7 mV), high transmittance (97.8%), and high strength (0.7% w/w). In vitro release and ex vivo permeation of CVE6 were found to be substantially high as compared to anionic AVE6 and respective gels. A penetration study using confocal laser scanning microscopy (CLSM) executed high fluorescence intensity with CVE6 and CVE6-gel as compared to suspension and ANE6. This might be attributed to the electrostatic interaction existing between the mucosal membrane and nanoglobules. Thus, cationic nanoemulsions and respective mucoadhesive gels are promising strategies for the delivery of VA to the brain through intransal administration for the treatment of seizures and convulsions.

Nanoemulsion curcumin injection showed significant anti-inflammatory activities on carrageenan-induced paw edema in Sprague-Dawley rats

Medicinal plants are candidates for the discovery of potential new anti-inflammatory agents. Curcumin is the active compound found in turmeric root, which has high anti-inflammatory activity. One of the limitations of curcumin as a therapeutic agent is its low solubility in water and extensive first-pass effect metabolism. The aim of this study was to formulate curcumin nanoemulsion for parenteral injection. We prepared curcumin nanoemulsions with a homogenizer using three surfactant concentrations (1.8%; 2.4%; and 3%) and two curcumin concentrations (1% and 3%). Formulas were evaluated for droplet diameter, polydispersity index, zeta potential, viscosity, pH, entrapment efficiency (EE), osmolality, sterility, and morphology. The nanoemulsion containing 1% curcumin and 3% surfactant (F3) demonstrated good stability. Curcumin nanoemulsions at 20 and 40 mg/kg doses showed anti-inflammatory activity on carrageenan-induced paw edema in male Sprague-Dawley rats. These two doses inhibited paw edema by 33% and 56% respectively at 5 h after carrageenan induction. Inhibition of edema volume by curcumin nanoemulsion at a dose of 40 mg/kg did not show a significant difference (P > 0.05) compared to the activity of the standard drug ketorolac at a dose of 2.7 mg/kg. We conclude that curcumin nanoemulsion has anti-inflammatory activity and can be a promising anti-inflammatory agent.

Thin film hydration versus modified spraying technique to fabricate intranasal spanlastic nanovesicles for rasagiline mesylate brain delivery: Characterization, statistical optimization, and in vivo pharmacokinetic evaluation

Rasagiline mesylate (RM) is a monoamine oxidase inhibitor that is commonly used to alleviate the symptoms of Parkinson's disease. However, it suffers from low oral bioavailability due to its extensive hepatic metabolism in addition to its hydrophilic nature which limits its ability to pass through the blood-brain barrier (BBB) and reach the central nervous system where it exerts its pharmacological effect. Thus, this study aims to form RM-loaded spanlastic vesicles for intranasal (IN) administration to overcome its hepatic metabolism and permit its direct delivery to the brain. RM-loaded spanlastics were prepared using thin film hydration (TFH) and modified spraying technique (MST). A 2³ factorial design was constructed to study and optimize the effects of the independent formulation variables, namely, Span type, Span: Brij 35 ratio, and sonication time on the vesicles᾽ characteristics in each preparation technique. The optimized system prepared using MST (MST 2) has shown higher desirability factor with smaller PS and higher EE%; thus, it was selected for further in vivo evaluation where it revealed that the extent of RM distribution from the intranasally administered spanlastics to the brain was comparable to that of the IV drug solution with significantly high brain-targeting efficiency (458.47%). These results suggest that the IN administration of the optimized RM-loaded spanlastics could be a promising, non-invasive alternative for the efficient delivery of RM to brain tissues to exert its pharmacological activities without being dissipated to other body organs which subsequently may result in higher pharmacological efficiency and better safety profile.

Recent Advances in Intranasal Liposomes for Drug, Gene, and Vaccine Delivery

Liposomes are safe, biocompatible, and biodegradable spherical nanosized vesicles produced from cholesterol and phospholipids. Recently, liposomes have been widely administered intranasally for systemic and brain delivery. From the nasal cavity, liposome-encapsulated drugs and genes enter the systemic circulation primarily via absorption in the respiratory region, whereas they can be directly transported to the brain via the olfactory pathway. Liposomes can protect drugs and genes from enzymatic degradation, increase drug absorption across the nasal epithelium, and prolong the residence time in the nasal cavity. Intranasal liposomes are also a potential approach for vaccine delivery. Liposomes can be used as a platform to load antigens and as vaccine adjuvants to induce a robust immune response. With the recent interest in intranasal liposome formulations, this review discusses various aspects of liposomes that make them suitable for intranasal administration. We have summarized the latest advancements and applications of liposomes and evaluated their performance in the systemic and brain delivery of drugs and genes administered intranasally. We have also reviewed recent advances in intranasal liposome vaccine development and proposed perspectives on the future of intranasal liposomes.