Current Drug Delivery - Volume 14, Issue 5, 2017

Background: According to the US Center for Disease Control, cancer deaths are the second most common cause of mortality in both adults and children. Definitive treatment of solid tumors involves surgical resection with or without systemic chemotherapy and radiation. The advent of local drug delivery presents a unique treatment modality that can offer substantial benefits in cancer management. Three main phases in solid tumor management exist for the treating physician: initial diagnosis with tissue biopsy, surgical resection with or without chemotherapy, and management of metastatic disease. Methods: A literature review of both basic science as well as clinical trials using local drug delivery strategies in the management of solid tumors was done on PubMed. These were then further divided into the categories of initial tissue biopsy intervention, surgical resection, and management of metastatic disease. Results: A total of 27 articles were review that included both pre-clinical as well as clinical investigation of local drug delivery therapies in the treatment of solid tumors. Treatments such as MRI guided therapies, FDA approved local therapies for intracranial gliomas as well as local therapy for single site metastatic disease were identified. Conclusion: This review focuses the current state of local drug delivery in the treatment of solid tumors in both the pre-clinical as well as clinical investigation settings. Local drug delivery therapy offers an exciting new treatment modality for solid malignancies.

Background: Squamous cell carcinoma of skin has become an important matter of discussion worldwide due to high number of deaths. Treatment of such cancer involves use of drugs (chemotherapy) along with surgery or radiation therapy. The combination chemotherapy is preferred over single treatment modality may be due to synergistic effect of targeting agent resulting in reduced drug dose, reduced cytotoxic effect and improved efficacy and survival rate. The objective of this work is to provide insight into the squamous cell carcinoma of skin; the various approaches and challenges adapted to surmount the cancer malignancies. Methods: Research evidence shows that nanoparticle based therapeutic delivery to squamous cell carcinoma is equanimous to lead therapeutic approaches for intervention of cancer growth. Active chemotherapeutic approach is one of the leading therapies to such cancer cells due specific selectivity towards the EGFR-receptors over-expressed in tumor cells. Review of numerous research publications revealed innate toxicity of chemotherapeutic agents, and substantiated active receptor mediated drug targeting for therapeutic regime. These actively functionalized nanoparticles have been delivered to the targeted cells with higher selectivity, minimal toxicity and better retention in the cell. Results: Numerous approaches and strategies have been designed till date for successful delivery of drug to cancer cells. The techniques have shown tremendous improvement in getting normalcy of carcinomas but a few have been marketed so far. Conclusion: Indeed, receptor based drug targeting approach through molecular signal transduction pathways involved in skin cancer development will provide insight into squamous carcinoma. Despite of these, other such challenges in drug delivery to squamous cell carcinoma need further clarification.

Background: The success story of liposomes in the treatment of systemic infectious diseases and various carcinomas lead the scientists to the innovation of elastic vesicles to achieve similar success through transdermal route. In this direction, ethosomes and transfersomes were developed with the objective to design the vesicles that could pass through the skin. However, there is a lack of systematic review outlining the principles, method of preparation, latest advancement and applications of ethosomes and transfersomes. This review covers various aspects that would be helpful to scientists in understanding advantages of these vesicular systems and designing a unique nano vesicular delivery system. Methods: Structured search of bibliographic databases for previously published peer-reviewed research papers was explored and data was culminated in terms of principle of these vesicular delivery systems, composition, mechanism of actions, preparation techniques, methods for their characterization and their application. Results: A total of 182 papers including both, research and review articles, were included in this review in order to make the article comprehensive and readily understandable. The mechanism of action and composition of ethosomes and transfersomes was extensively discussed. Various methods of preparation such as, rotary film evaporation method, reverse phase evaporation method, vortex/ sonication method, ethanol injection method, freeze thaw methods, along with their advantages has been discussed. It was also discussed that both these elastic nanocarriers offer unique advantages of ferrying the drug across membranes, sustaining drug release as well as protecting the encapsulated bio actives from external environment. The enhanced bioavailability and skin penetration of ethosomes as compared to conventional vesicular delivery systems is attributed to the presence of ethanol in the bilayers while that for transfersomes accrues due to their elasticity along with their ability to retain their shape because of the presence of edge activators. Successful delivery of synthetic drugs as well as phytomedicines has been extensively reported through these vesicles. Conclusion: Though these vesicular systems offer a good potential for rational drug delivery, a thoughtfully designed process is required to optimize the process variables involved. Industrial scale production of efficacious, safe, cost effective and stable formulations of both these delivery systems appears to be a pre-requisite to ensure their utility as the trans-dermal vehicles.

Background: In the previous study, buccal absorption of ritodrine (RD) hydrochloride was reported in vivo. As a result, buccal dosing of RD solution was found to be useful for the maintenance of effective plasma concentration. However, in order to find out the dosing schedule more clearly, it is important to clarify the in vivo drug behavior. Objective: The biodistributions of RD in oral cavity and buccal mucosal were investigated in order to understand the in vivo drug behavior after the buccal application. Method: The pharmacokinetic parameters for 0 – infinite time and the absorption rate were calculated based on the plasma level-time profiles in the intravenous (1 mg/kg), buccal (10 mg/kg) and intragastric (10 mg/kg) dosings using rats. The drug concentrations in buccal mucosa and the remaining drug amounts in the oral cavity were examined over time after the buccal administration. From those drug distributions and drug absorption rates, the kinetic aspects were discussed. Results: The absolute bioavailabilities of RD were 14.2% and 4.3% in buccal and intragastric (0.043) administrations, respectively. The oral cavity concentration was quickly eliminated within 0.5 h, and then decreased slowly. In both the administration site and distant region, the mucosal RD concentrations were observed at several dozen to approximately 100 μg/g during 0.5-4 h, indicating the rapid diffusion in the oral cavity. For both the mucosal parts, the buccal mucosal level reached a maximal level at 1 h, and then was slowly eliminated. The absorption rates were not related linearly to the buccal mucosal level, suggesting that the other mucosal parts such as sublingual mucosa and tongue ventral surface should be involved considerably in the absorption. Conclusion: The changes in RD concentration in oral cavity and oral mucosa showed the drug behavior in vivo. The present study revealed that RD is not accumulated in the buccal mucosa and transfers relatively fast from the oral mucosa to systemic circulation. It was suggested that the buccal dosing of RD should be acceptable even in the repeated manner as an alternative to the intravenous or oral administration of RD.

Background: Flutamide (FLT) is a non steroidal antiandrogenic drug used to treat prostate cancer. Its poor aqueous solubility and toxicity are the major hindrance for oral drug delivery. The aims of this study are to introduce nanoformulation of flutamide to increase its aqueous solubility thereby improves the therapeutic efficacy of the chemodrug. Methods: Poly (vinyl alcohol) (PVA) coated flutamide nanoparticles (PVA FLT NPs) were formulated by nanoprecipitation method and characterized by DLS, TEM, FTIR, Drug release profile and biological assays. Results: The PVA FLT nanoparticles were about 300nm size and spherical in shape. The PVA coated flutamide nanoparticles were monodispersed and polycrystalline. The FTIR spectra confirmed the encapsulation of flutamide in PVA FLT NPs. The encapsulation efficiency and loading efficiency was found to be about 78% and 15% respectively. The in vitro drug release of nanoparticles was calculated and it showed a sustained release up to 120 hrs at pH 7.4. The in vitro cytotoxicity, colony forming ability and blood compatibility were also investigated. The in vitro cytotoxicity study indicated the dose dependent cytotoxicity of PVA FLT NPs. In vitro clonogenic assay revealed that the PVA FLT NPs treated PC3 cells had less colony forming ability than the untreated PC3 cells. In vitro hemolysis assay and blood aggregation studies confirmed the hemocompatibility of the prepared PVA FLT NPs. Conclusion: We reported PVA coated FLT NPs were prepared by nanoprecipitation were more aqueous soluble than FLT, which increased its therapeutic efficacy for prostate cancer cells.

Purpose: This study aimed to develop a synchronized and sustained-release silymarin dropping pill, and to evaluate its pharmacokinetic characteristics. Method: Polyoxyethylene stearate, glyceryl monostearate, and stearic acid were used to prepare the dropping pills. X-ray powder diffraction, differential scanning calorimetry, and release were used to evaluate its physicochemical properties. The plasma concentration of silybin in beagle dogs after oral administration of silymarin dropping pills and silymarin capsule was determined by RP-HPLC. Results: Synchronized release was achieved with high similarity factor f2 values between every set of two of the five components. Mean plasma concentration-time curves of silymarin after oral administration of dropping pills in beagle dogs were in accordance with first-order absorption and open twocompartment model. The Tmax, Cmax, and AUC0-∞ of dropping pills in beagle dogs were 0.8750±0.13 h, 0.8183±0.07 μgml-1, and 2.274±0.90 μghml-1, respectively. Silymarin dropping pills prolonged in vivo exposure and reduced maximum in vivo concentration, achieving a stable level in the serum. Conclusion: The combination of solid dispersion technique and dropping pill formulation allowed synchronized release of multiple components in herbal medicine, and has potential application in the development of sustained release in herbal medicine.

Background: Antifungal agents incorporated into temporary denture resilient liners as drug carriers and delivery have been suggested as an alternative treatment for denture stomatitis. However, to test the in vivo biocompatibility of this protocol, standardization of an intraoral device for optimal drug delivery is required. Objective: Standardized criteria were produced to adjust an acrylic intraoral device (IOD) for rats feasible for denture stomatitis treatment by sustained drug-delivery based on minimal inhibitory drug concentrations (MICs) of antifungals for Candida albicans biofilm. Method: Adjustments methodological involved diet, impression technique, type of retention device to the palate and histopathological analysis. 115 Wistar rats were tested without IOD, with devices without relining or relined with temporary resilient material (Trusoft) modified or not by drugs at MICs (nystatin-0.032g/mL; chlorhexidine diacetate-0.064g/mL; ketoconazole-0.128g/mL). The animals were sacrificed after 7 or 14 days from the IOD installation. Results: Paste diet enabled the best animal survival conditions. The IODs that most satisfactorily remained in position were those designed only to the posterior palatal mucosa and cement-retained in molars, being all obtained from impressions highly detained and individual. In both periods, Trusoft without/with drugs showed good performance. Only histological samples from hard/soft tissues were considered appropriate for region of interest-RI determination (n=12), which corresponded to the area restricted to the first molars between the palatal neurovascular bundles. Final samples of all groups allowed a standardized descriptive histopathological analysis in both periods. Conclusion: The methodological standardization of this rat model resulted in IODs for optimal antifungal delivery for denture stomatitis treatment.

Background: We have previously reported the synthesis of a novel polyethyleneglycol (PEG) lipid, 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-PEG (DDA-PEG). This study aimed to clarify the anti-metastatic effect and localization of DDA-PEG-modified liposomes on a murine hepatic metastasis model. Methods: M5076 ovarian sarcoma cells were inoculated for hepatic metastasis model mice. The accumulation of liposomes in the tumor and metastatic sites was detected by fluorescent imaging device. In metastasis study, doxorubicin (DOX) loaded DDA-PEG-modified liposome (DDA-LDOX) was injected. Alexa Fluor 790 NHS Ester loaded DDA-PEG-modified liposomes were used to detect fluorescence intensity at metastatic sites when visualized topically using a fluorescence imaging device. Results: DDA-PEG-modified liposomes accumulated at the sites of hepatic metastasis but not in the normal hepatocytes. Furthermore, the DDA-LDOX inhibited metastasis in this model. The survival time of M5076 ovarian sarcoma bearing mice in DDA-LDOX group was longer than those in control, DOX solution and the other PEG-modified liposomal DOX groups, and the survival ratio in DDALDOX group remained 66.7% until 60 days after treatment. Conclusion: It is expected that the DDA-PEG-modified liposomes will extensively contribute in clinical practice as a superior drug carrier because this liposomes proved to be effective against metastasis.

Background: Abstract: The objective of the present work was to prepare and optimize the loteprednoletabonate (LE) loaded poly (D,L-lactide co-glycolide) (PLGA) polymer based nanoparticle carrier. The review on recent patents (US9006241, US20130224302A1, US2012/0028947A1) assisted in the selection of drug and polymer for designing nanoparticles for ocular delivery applications. Methods: The nanoparticles were prepared by solvent evaporation followed by high speed homogenization. Biodegradable polymer PLGA (50:50) grade was utilized to develop various formulations with different drug:polymer ratio. A Box-Behnken design with 33 factorial design was selected for the present study and 17 runs were carried out in totality. The influence of various process variables (viz., polymer concentration, homogenization speed and sonication time) on the characteristics of nanoparticles including the in vitro drug release profile were studied. Results: The nanoparticulate formulations were evaluated for mean spherical diameter, polydispersity index (PDI), zeta potential, surface morphology, drug entrapment and in-vitro drug release profile. The entrapment efficiency, drug loading and mean particle size were found to be 96.31±1.68 %, 35.46±0.35 % and 167.6±2.1 nm respectively. Conclusion: The investigated process and formulation variables were found to have significant effect on the particle size, drug loading (DL), entrapment efficiency (EE), and in vitro drug release profile. A biphasic in vitro drug release profile was apparent from the optimized nanoparticles (NPs) for 24 hours.

Background: Topical local anaesthetic cream was reported to be useful for pain relief for cutaneous procedures such as minor surgery and venipuncture. Objective: The aim of this study was to evaluate the effectiveness of new formulation of lidocaine topical anaesthetic using palm oil base, HAMIN® and to determine how fast this new formulation produces adequate numbness compared to the currently used EMLA cream, in the University of Malaya Medical Centre (UMMC) set-up. Method: The skin permeation test was conducted by using Franz type diffusion cell and pain assessment was carried out in healthy subject by using Verbal Rating Score (VRS) and Visual Analogue Score (VAS) evaluation. Result: Result of permeation test demonstrated that the cumulative amount of lidocaine released from HAMIN® cream was increased with time and slightly higher than EMLA cream. The clinical study showed that HAMIN® single lidocaine cream can produces numbness through venepuncture procedure and comparable with EMLA cream which is a combination therapy for local anaesthetic (lidocaine and prilocaine). Conclusion: It can be concluded that HAMIN® Lidocaine cream is suitable for cream preparation especially for topical application and it can be regarded as an achievement in palm oil and medical industries.

Background: Oxandrolone is a potent synthetic testosterone analogue that possesses strong anabolic property and weak androgenic activity. Apart of their clinical implicances, oral oxandrolone can potentially promote several adverse effects. It is known that the transdermal delivery of drugs may represent a means to avoid or minimize oral adverse effects Thus, the objective of this study was to evaluate the permeability of oxandrolone in human skin on a preliminary basis for possible future determination of the transdermal route as an alternative to oral treatments. Methods: We used a percutaneous absorption assay in Franz diffusion cells coupled with freshly excised human skin. The drug release kinetics were determined to predict the efficiency of this alternative route for the drug. Results: Nearly 236 μg (86.7%, in terms of applied dose) of the product was prevented to permeate due to the barrier function of the stratum corneum (SC); 21.6% reached the receptor medium (RM), and the remaining 4.3% were quantified within viable layers of the skin (in vivo, dermis is vascularized). The total amount of drug able to exert effect is the sum of the drug quantified within remained skin (RS) and RM: then, a total of 247.6 μg of oxandrolone (25.9% of the applied dose) would be able to permeate through a non damaged skin. The accuracy of the data is demonstrated by the calculated mass balance (average recovery = 112.6%). Conclusion: Transdermal oxandrolone could be a viable alternative for traditional oral form, once clinical studies are conducted to prove this hypothesis.

Background: Group A streptococcus (GAS) primarily colonizes the mucosal region of the upper respiratory tract, slowly leading to systemic infections. Thus, GAS-specific antibody responses are desirable at mucosal sites for early prevention against GAS colonization. Methods: Herein, we developed a potent nanoliposomes-based delivery system for mucosally active lipid core peptide (LCP)-based vaccines. Results: Trimethyl chitosan (TMC)-coated liposomes that bore a B-cell epitope derived from GAS Mprotein, stimulated potent epitope-specific mucosal and systemic antibody titres after only one boost following intranasal immunization in Swiss outbred mice. The immune responses were durable even at day 139 post-primary immunization. Conclusion: The enhanced vaccine efficacy, lowered dose, and simple and cost-effective process of producing the coated nanoliposomes should be particularly useful in developing potent peptide-based vaccines to prevent infections at the mucosal sites.

Background: Meloxicam (MLX) is classified as NSAID that is used for the treatment of rheumatoid arthritis and osteoarthritis. Poor water solubility of MLX leads to its slow oral absorption and slow onset. Preparation of solid dispersion (SD) could improve the water solubility of poorly water soluble drugs. It has been demonstrated that orally disintegrating tablets (ODTs) show faster onset of action and could be more appropriate for the treatment of acute pain. Method: The purpose of this study is to improve the solubility of MLX through the preparation of its SD and then decrease the onset of action by preparation of ODTs from prepared SD. MLX SDs were prepared by solvent evaporation method. MLX, polyvinylpyrrolidone k30 (PVP k30), crospovidone and sodium lauryl sulfate (SLS) with different ratios were dispersed in molten menthol as solvent. Menthol was separated by freeze drying. Differential scanning calorimetry (DSC) and X-ray diffraction (XRD) analysis approved amorphous form of MLX in SDs. Result: The optimum SD with highest saturation solubility in water (12.60±1.2 microgram/ml) which consists of MLX, PVP, crospovidone and SLS in a ratio of 1:1:1:0.03 was used for the preparation of MLX ODTs. ODTs were prepared by direct compression method and optimized by 23 factorial design. The effect of the superdisintegrant concentration, mannitol/avicel ratio and the level of compression force was evaluated on the disintegration time, hardness and percent of dissolved MLX after 30 min of prepared MLX ODTs. The optimized ODT formulation contained 10% superdisintegrant, mannitol and avicel a ratio of 2:1 compressed using a high level of compression force. Conclusion: Optimized ODT showed hardness (48±4.3 N) and friability (0.81±0.07%). This formulation provided rapid disintegration in 19±2 seconds of which 77.8±5.1% of drug was released within 30 minutes. The present study demonstrated an effective method for the preparation of suitable dosage form of MLX with improved solubility and onset of action.

Background: Voriconazole (VCZ), a second-generation antifungal with excellent attributes like, broad-spectrum activity, targeted delivery, and tolerability. VCZ loaded microemulsion could be an effective strategy for efficient ocular delivery of the drug. Objective: To perform corneal irritation studies and in vivo delivery of VCZ microemulsion to establish its potential as an efficient ocular delivery system. Methods: Ocular irritancy was performed by HETCAM (Hen's Egg Test Chorio Allantoic Membrane) assay, corneal histopathology and Draize test. Ex vivo and in vivo studies were performed to determine permeation efficiency of VCZ microemulsion. Results: The irritation studies suggested the non-irritant nature of the microemulsion. The ex vivo studies performed on excised cornea displayed significant enhancement in drug permeation/penetration from microemulsion in contrast to the drug suspension. Further, the in vivo study confirmed the higher availability of VCZ (from microemulsion) in aqueous humor with minimal nasolacrimal drainage (lower plasma drug content) when compared with the drug suspension. Conclusion: The non-irritant nature and high corneal permeation of VCZ encourages the role of microemulsion as a potential ocular delivery system.

Background: Sore throat sprays provide targeted relief by delivering the active ingredient directly to the site of pain. Different sprays vary in characteristics, thus affecting delivery of the active ingredient to the throat, which can impact compliance. Objective: The characteristics and performance of FLURBIPROFEN 8.75 mg SPRAY were compared with 12 other sprays. Method: Parameters assessed included spray angle and pattern, droplet size distribution, shot weight uniformity and shot weight throughout life. Results: Among all sprays tested WICK Sulagil Halsspray had the smallest spray angle (46°) and also the smallest diameter spray pattern (X=32.8 mm; Y=34.4 mm). Thiovalone® Buccal Spray Suspension had both the largest spray angle (82°) and largest diameter spray pattern (X=62.6 mm; Y=78.0 mm). Hasco Sept® Aerosol Spray had the smallest droplet size (Dv90=118.4 μm) whereas OKi infiammazione e dolore® 0.16% spray had the largest (Dv90=214.34 μm). In terms of shot weight uniformity, TANTUM® VERDE GOLA 0.25% spray showed the least variation (2% RSD) between shots and UNIBEN Aerosol Spray the most (23.4% RSD). Shot weight throughout life studies showed that FLURBIPROFEN 8.75 mg SPRAY had the least deviation from shot weight (1.77%) whereas OKi infiammazione e dolore® 0.16% spray deviated the most (44.9%). FLURBIPROFEN 8.75 mg SPRAY had the second smallest spray angle/pattern and droplet size distribution and also the least variation in shot weight. Conclusion: Different sore throat sprays vary in different attributes, affecting delivery of the active ingredient. FLURBIPROFEN 8.75 mg SPRAY performed well overall, ranking first among all sprays tested, and providing a dose which is targeted and uniformly delivered throughout the life of the bottle.

Background: Warfarin, commonly used anticoagulant in clinic, has serious shortcomings due to its unsatisfactory pharmacodynamics. One of the efficient ways for the improvement of pharmacological and consumer properties of drugs is the development of optimal drug delivery systems. Objective: The aim of this work is to synthesize novel warfarin – silica composites and to study in vitro the drug release kinetics to obtain the composites with controlled release. Methods: The composites of warfarin with unmodified (UMS) and mercaptopropyl modified silica (MPMS) were synthesized by sol-gel method. The composite formation was confirmed by FTIR spectra. The concentrations of warfarin released to media with pH 1.6, 6.8 and 7.4 were measured using UV spectroscopy. The drug release profiles from the solid composites were described by a series of kinetic models which includes zero order kinetics, first order kinetics, the modified Korsmeyer-Peppas model and Hixson-Crowell model. Results: The synthesized sol-gel composites have different kinetic behavior in the studied media. In contrast to the warfarin composite with unmodified silica, the drug release from the composite with mercaptopropyl modified silica follows zero order kinetics for 24 h irrespective to the release medium pH due to mixed mechanism (duffusion + degradation and/or disintegration of silica matrix). Conclusion: The obtained results showed that warfarin – silica sol-gel composites have a potential application for the development of novel oral formulation of the drug with controlled delivery.