Development of Oral Tablet Formulation Containing Erlotinib: Randomly Methylated-ß-cyclodextrin Inclusion Complex Using Direct Compression Method

Objectives: Erlotinib (ERL) is a tyrosine kinase inhibitor that has been used in the treatment of metastatic non-small cell lung cancer (NSCLC). However, its low aqueous solubility limits its absorption and oral bioavailability. To overcome these pharmacokinetic drawbacks, complexation of ERL can be applied. The aim of this study was to develop and characterize an oral tablet formulation containing ERL: Randomly methylated-ß-cyclodextrin (RAMEB-CD) inclusion complex to enhance solubility and oral bioavailability of ERL. Materials and Methods: An inclusion complex was prepared with RAMEB-CD using co-lyophilization technique. Structural characterization was performed using X-ray diffractometry and fourier-transform infrared spectroscopy. Tablet formulation of ERL: RAMEB-CD inclusion complex were prepared using direct compression technique. Tablet characteristics like hardness, diameter, thickness, friability, weight variability, disintegration and dissolution were evaluated. Flow properties of the powder were also determined. Results: Characterization studies suggested that stable complexes between ERL and RAMEB-CD were obtained with co-lyophilization method. Tablet formulation using inclusion complex of ERL and RAMEB-CD with drug dose equivalent to 25 mg was successfully prepared using direct compression technique. Physical properties of the powder mixture were studied - angle of repose (°): 34.27±1.78; flow time: 2.2±0.4; HR: 1.05±0.02; compressibility index: 14.27±1.55. Moisture content (%) was found to be 0.27±0.05. The thickness, diameter and hardness values were 3.92±0.05 mm, 11.3±0.06 mm and 81.38±2.27 N, respectively. In uniformity of weight test, the average weight was 404.57±1.6 mg, with less than 5% deviation in 20 randomly selected tablets. Friability value was 0.27% and the disintegration time was found to be less than 15 min. Importantly, dissolution study showed that solubility of ERL was increased by complexation with RAMEB-CD. After 60 minutes, 99% of drug was released from the tablet formulation. Conclusion: These results demonstrate that a new tablet formulation of ERL: RAMEB-CD inclusion complex could be an alternative approach to achieve increased dissolution and oral bioavailability of ERL for NSCLC treatment.

Erlotinib complexation with randomly methylated ß-cyclodextrin improves drug solubility, intestinal permeability, and therapeutic efficacy in non-small cell lung cancer.

The purpose of this study was to investigate the impact of anticancer drug erlotinib-randomly methylated-ß-cyclodextrin complex (ERL-RAMEB CD) on drug solubility and dissolution rate. Phase solubility study showed erlotinib displayed maximum solubility in RAMEB CD solution and the stability constant (Kc) was calculated to be 370 ± 16 M-1. The optimal formulation was obtained with ERL-RAMEB CD in a 1:1 molar ratio using the co-lyophilization technique. Differential scanning calorimetry (DSC) and Scanning electron microscopy (SEM) verified the inclusion of complex formation. In vitro dissolution study confirmed ERL-RAMEB CD as a favorable approach to increase drug dissolution with a 1.5-fold increase than free ERL at 1 h. An improved dissolution with ∼88.4% drug release at 1 h was observed, in comparison with Erlotinib with ∼58.7% release in 45 min. The in vitro cytotoxicity results indicated that the ERL-RAMEB CD inclusion complex reduced cell viability than free erlotinib. Caco-2 cell uptake that is indicative of drug intestinal permeability resulted in a 5-fold higher uptake of ERL-RAMEB CD inclusion complex than the ERL solution. Hence, ERL-RAMEB CD complexation displays a strong potential to increase dissolution and permeability of erlotinib leading eventually to enhanced oral bioavailability.

Determination and validation of aprepitant in rat plasma using LC-MS/MS.

Aim: The assessment of efficacy should be paralleled with extensive pharmacokinetic parameters, and a valid bioanalytical method is a pre-condition for accurate plasma concentration. Materials & methods: A simple, specific, rapid and sensitive LC-MS/MS method has been developed for quantitative analysis of aprepitant in rat plasma. A C18 column was used as stationary phase and the mobile phase consisted of a mixture of formic acid in water and formic acid in acetonitrile. Quantification was performed using multiple reaction monitoring mode. Results: The selectivity, linearity, accuracy, precision, robustness and ruggedness of the method were evaluated in accordance with bioanalytical method validation guideline of ICH and all results were within the acceptable range. Conclusion: The validated LC-MS/MS method was found to be useful for the quantitative analysis of aprepitant in rat plasma samples.

Therapeutic efficacy of folate receptor-targeted amphiphilic cyclodextrin nanoparticles as a novel vehicle for paclitaxel delivery in breast cancer.

PURPOSE: The aim of this study is to test folate-conjugated cyclodextrin nanoparticles (FCD-1 and FCD-2) as a vehicle for reducing toxicity and increasing the antitumor efficacy of paclitaxel especially for metastatic breast cancer. METHODS: For the evaluation of PCX-loaded FCD nanoparticles, animal studies were realised in terms of survival rate, tumour size, weight change, metastazis and histopathological examination. RESULTS: FCD-1 displayed significant advantages such as efficient targeting of folate receptor positive breast cancer cells and having considerably lower toxicity compared to that of Cremophor®. When loaded with paclitaxel, FCD-1 nanoparticles, which have smaller particle size, neutral zeta potential, high encapsulation efficiency and better loading capacity for controlled release, emerged as an effective formulation in terms of cytotoxicity and high cellular uptake. In an experimental breast cancer model, anticancer activity of these nanoparticles were compatible with that of paclitaxel in Cremophor® however repeated administrations of FCD-1 nanoparticles were better tolerated by the animals. These nanoparticles were able to localise in tumour site. Both paclitaxel-loaded FCD-1 and FCD-2 significantly reduced tumour burden while FCD-1 significantly improved the survival. CONCLUSIONS: Folate-conjugated amphiphilic cyclodextrin nanoparticles can be considered as promising Cremophor®-free, low-toxicity and efficient active drug delivery systems for paclitaxel.

Nanocapsules for Drug Delivery: An Updated Review of the Last Decade.

BACKGROUND: For the past few decades, there has been considerable research interest in drug delivery strategies using nanoparticulate systems as carriers for a wide range of active pharmaceutical ingredients. OBJECTIVE: It is known that nanoparticulate drug delivery systems comprise a wide variety of dosage forms including nanospheres, micelles, solid lipid nanoparticles, nanoliposomes, dendrimers, magnetic nanoparticles, and nanocapsules. METHODS: This review describes nanocapsule preparation techniques and their applications for the treatment of several diseases using patents and examples from the literature. RESULTS: Nanocapsules are vesicular systems consisting of an inner liquid core (aqueous/oily) surrounded by a polymeric wall that has immense potential as drug carriers because of the many advantages like improving poor aqueous solubility, stabilizing drugs by protecting the molecule from the environment, providing the desired pharmacokinetic profile, allowing controlled release, as well as facilitating oral administration. CONCLUSION: The present study discusses and summarizes patents related to preparation methods of and recent studies from the last 10 years on nanocapsules as drug delivery systems.

Amphiphilic cyclodextrin nanoparticles.

Cyclodextrins are cyclic oligosaccharides obtained by enzymatic digestion of starch. The α-, ß- and γ- cyclodextrins contain respectively 6, 7 and 8 glucopyranose units, with primary and secondary hydroxyl groups located on the narrow and wider rims of a truncated cone shape structure. Such structure is that of a hydrophobic inner cavity with a hydrophilic outer surface allowing to interact with a wide range of molecules like ions, protein and oligonucleotides to form inclusion complexes. Many cyclodextrin applications in the pharmaceutical area have been widely described in the literature due to their low toxicity and low immunogenicity. The most important is to increase the solubility of hydrophobic drugs in water. Chemically modified cyclodextrin derivatives have been synthesized to enhance their properties and more specifically their pharmacological activity. Among these, amphiphilic derivatives were designed to build organized molecular structures, through selfassembling systems or by incorporation in lipid membranes, expected to improve the vectorization in the organism of the drug-containing cyclodextrin cavities. These derivatives can form a variety of supramolecular structures such as micelles, vesicles and nanoparticles. The purpose of this review is to summarize applications of amphiphilic cyclodextrins in different areas of drug delivery, particularly in protein and peptide drug delivery and gene delivery. The article highlights important amphiphilic cyclodextrin applications in the design of novel delivery systems like nanoparticles.

Amphiphilic Cyclodextrin Derivatives for Targeted Drug Delivery to Tumors.

Villiers has extensively studied cyclodextrins, a family of macrocyclic oligosaccharides linked by α-1,4 glycosidic bonds, in different fields since their discovery in 1891. The unique structure enabling inclusion complexation for natural cyclodextrins and cyclodextrin derivatives make them attractive for novel drug delivery systems. Cyclodextrins can be modified with long aliphatic chains to render an amphiphilic property and these different amphiphilic cyclodextrins are able to form nanoparticles without surfactants. In the literature, several different amphiphilic cyclodextrins are reported and applied to drug delivery and targeting especially to tumors. Specificly, folateconjugated amphiphilic cyclodextrin derivatives are used for active tumor targeting of poorly water soluble drugs and improve the efficacy and safety of therapeutic agents. On the other hand, effect of positive surface charge has also been under research in the recent years. Polycationic amphiphilic cyclodextrins have shown promise towards forming small complexes with negatively charged molecules such as drugs or plasmid DNA. Polycationic amphiphilic cyclodextrins enhance interaction with cell membrane due to their net positive surface charge. The scope of this review is to describe potential uses and pharmaceutical applications of tumor-targeted amphiphilic cyclodextrins, with focus on folate-conjugated cyclodextrin derivatives and polycationic cyclodextrin derivatives both studied by our group at Hacettepe University.

Design and optimization of novel paclitaxel-loaded folate-conjugated amphiphilic cyclodextrin nanoparticles.

As nanomedicines are gaining momentum in the therapy of cancer, new biomaterials emerge as alternative platforms for the delivery of anticancer drugs with bioavailability problems. In this study, two novel amphiphilic cyclodextrins (FCD-1 and FCD-2) conjugated with folate group to enable active targeting to folate positive breast tumors were introduced. The objective of this study was to develop and characterize new folated-CD nanoparticles via 3(2) factorial design for optimal final parameters. Full physicochemical characterization studies were performed. Blank and paclitaxel loaded FCD-1 and FCD-2 nanoparticles remained within the range of 70-275nm and 125-185nm, respectively. Zeta potential values were neutral and -20mV for FCD-1 and FCD-2 nanoparticles, respectively. Drug release studies showed initial burst release followed by a longer sustained release. Blank nanoparticles had no cytotoxicity against L929 cells. T-47D and ZR-75-1 human breast cancer cells with different levels of folate receptor expression were used to assess anti-cancer efficacy. Through targeting the folate receptor, these nanoparticles were efficiently engulfed by the breast cancer cells. Additionally, breast cancer cells became more sensitive to cytotoxic and/or cytostatic effects of PCX delivered by FCD-1 and FCD-2. In conclusion, these novel folate-conjugated cyclodextrin nanoparticles can therefore be considered as promising alternative systems for safe and effective delivery of paclitaxel with a folate-dependent mechanism.

Antitumor Efficacy of Bacillus Calmette-Guerin Loaded Cationic Nanoparticles for Intravesical Immunotherapy of Bladder Tumor Induced Rat Model.

For bladder cancer, intravesical chemo/immunotherapy is widely used as adjuvant therapy after surgical transurethral resection. Bacillus Calmette-Guerin (BCG) is a live attenuated Mycobacterium of the same family as tuberculosis, that is capable of inducing a local inflammatory response upon instillation into the bladder. Intravesical therapy with BCG has proved to be more effective in the prophylaxis and treatment of superficial bladder tumors than most chemotherapeutic agents used for the same indication. However, compared to intravesical chemotherapy, BCG immunotherapy provokes more pronounced local and systemic reactions. In addition to the commonly induced granulomatous inflammatory changes in the bladder, which produce irritative symptoms, this therapy may cause systemic side effects varying from mild malaise and fever to, in rare instances, life-threatening or fatal sepsis. Nanoparticles with positive surface charge and mucoadhesive properties were developed to overcome these side effects. Hence, the aim of this study was to optimize and evaluate cationic chitosan (CS) nanoparticles encapsulating BCG in terms of antitumor efficacy after intravesical administration in bladder tumor, induced in rat model. It was found that nanoparticle formulations of 269-375 nm in size can be produced with 42% encapsulation efficiency. The zeta potential was positive and was suitable for intravesical administration. Antitumor efficacy was determined over the parameters of histopathological evaluation, survival rate and mean bladder weight in comparison to treatment with commercial BCG solution. Concerning survival rates, BCG-loaded chitosan nanoparticles resulted in significantly longer survival than BCG commercial product (up to 86 days of survival with no systemic side effects). When compared to healthy bladder weight averages, all groups (especially BCG commercial solution) showed higher bladder weights confirming tumor formation. Histopathological findings confirmed antitumor activity in all treatment groups and optimum findings were observed in groups treated with CS nanoparticles encapsulating BCG. At the same time, significant nanoparticle accumulation in bladder tissues was observed especially for BCG-loaded CS group. In this study, it was clearly observed that cationic CS nanoparticles provide a significantly improved perspective in intravesical immunotherapy of bladder tumors.

Cationic core-shell nanoparticles for intravesical chemotherapy in tumor-induced rat model: safety and efficacy.

Mitomycin C (MMC) has shown potent efficacy against a wide spectrum of cancers and is clinical first choice in superficial bladder tumors. However, intravesical chemotherapy with MMC has been ineffective due to periodical discharge of the bladder and instability of this drug in acidic pH, both resulting in high rate of tumor recurrence and insufficiency to prevent progression. Nanocarriers may be a promising alternative for prolonged, effective and safe intravesical drug delivery due to their favorable size, surface properties and optimum interaction with mucosal layer of the bladder wall. Hence, the aim of this study was to evaluate and optimize cationic core-shell nanoparticles formulations (based on chitosan (CS) and poly-ϵ-caprolactone (PCL)) in terms of antitumor efficacy after intravesical administration in bladder tumor induced rat model. Antitumor efficacy was determined through the parameters of survival rate and nanoparticle penetration into the bladder tissue. Safety of the formulations were evaluated by histopathological evaluation of bladder tissue as well as observation of animals treated with MMC bound to nanoparticles. Results indicated that chitosan coated poly-ϵ-caprolactone (CS-PCL) nanoparticles presented the longest survival rate among all treatment groups as evaluated by Kaplan-Meier plotting. Histopathological evaluation revealed that cationic nanoparticles were localized and accumulated in the bladder tissue. As intravesical chemotherapy is a local therapy, no MMC was quantified in blood after intravesical instillation indicating no systemic uptake for the drug which could have subsequently led to side effects. In conclusion, core-shell type cationic nanoparticles may be effective tools for the intravesical chemotherapy of recurrent bladder tumors.

Prolonged retention and in vivo evaluation of cationic nanoparticles loaded with Mitomycin C designed for intravesical chemotherapy of bladder tumours.

To overcome the recurrence problem in bladder tumours; nanoparticles with positive surface charge may improve interaction with biological membranes for intravesical administration. The aim of this study was to design, develop and evaluate (in vitro-in vivo) cationic nanoparticles based on chitosan, poly-L-lysine or polycaprolactone for the effective intravesical delivery of chemotherapeutic agent MMC in a rat model. Poly-L-lysine-coated polycaprolactone nanoparticles and chitosan-coated polycaprolactone nanoparticles were prepared by the double emulsion technique. Chitosan nanoparticles were prepared by ionic gelation. It was found that nanoparticle formulations of 160-320 nm in size can be produced in 14-35% encapsulation efficiency. Variability in the particle size of nanoparticles depended on the preparation method. Encapsulation was increased by two-fold for CS-PCL as a result of the double emulsion technique. Commercial MMC product in solution form and cationic nanoparticle formulations were compared for in vivo bladder retention properties and effect of formulations on urine volume.