Preparation and characterisation of poly(vinyl alcohol)/cyclodextrin microspheres as matrix for inclusion and separation of drugs

Locoregional Therapies for Primary and Secondary Hepatic Malignancies

Management of hepatic malignancies is a multidisciplinary task with the involvement of hepatologists, medical/surgical/radiation oncologists, transplant surgeons, and interventional radiologists. Patients should be selected for a specific targeted therapy after multidisciplinary consensus. Interventional oncology, with image-guided locoregional cancer therapies, can decrease systemic toxicity without compromising tumoricidal effect.

Bisphenol A Adsorption on Silica Particles Modified with Beta-Cyclodextrins

This study presents the synthesis of silica particles bearing two beta-cyclodextrin (BCD) (beta-cyclodextrin-BCD-OH and diamino butane monosubstituted beta-cyclodextrin-BCD-NH2). The successful synthesis of the BCD-modified silica was confirmed by FT-IR and TGA. Using contact angle measurements, BET analysis and SEM characterization, a possible formation mechanism for the generation of silica particles bearing BCD derivatives on their surface was highlighted. The obtained modified silica displayed the capacity to remove bisphenol A (BPA) from wastewater due to the presence of the BCD moieties on the surface of the silica. The kinetic analysis showed that the adsorption reached equilibrium after 180 min for both materials with qe values of 107 mg BPA/g for SiO2-BCD-OH and 112 mg BPA/g for SiO2-BCD-NH2. The process followed Ho's pseudo-second-order adsorption model sustaining the presence of adsorption sites with different activities. The fitting of the Freundlich isotherm model on the experimental results was also evaluated, confirming the BCD influence on the materials' adsorption properties.

Characterization and Evaluation of Ternary Complexes of Ascorbic Acid with γ-Cyclodextrin and Poly(vinyl Alcohol)

Ascorbic acid (AA) is a general antioxidant used in aqueous pharmaceutical formulations. However, in aqueous solutions, AA is unstable and easily oxidized when exposed to air, light and/or heat. Cyclodextrins are well known for their ability to form inclusion complexes with various compounds to improve their solubility and stability. Previous studies demonstrate that cyclodextrins preserve the antioxidant capacity of AA but data for γ-cyclodextrin (γCD) have not been reported. Poly(vinyl alcohol) (PVA) is a hydrophilic polymer widely used as a drug matrix in various pharmaceutical fields, but its application for drug stabilization is limited. This study aimed to investigate the protective ability of γCD on AA through the formation of ternary complexes with PVA. Binary (i.e., AA/γCD, AA/PVA and γCD/PVA) and ternary (i.e., AA/γCD/PVA) complexes were first confirmed. It was reported that those complexes were formed through interactions between the heterocyclic ring of AA, hydroxyl group of PVA and hydrophobic cavity of γCD. The hydrodynamic diameter of complexes was then studied. It was found that the diameter of γCD/PVA complexes increased with respect to the concentration of γCD. Higher γCD concentrations also resulted in increasing hydrodynamic diameters of the ternary complex. The presence of AA in ternary complexes interfered with the aggregation tendency of γCD/PVA binary complexes. Furthermore, the antioxidant capacity of AA in binary and ternary complexes was investigated. It was found that the presence of γCD preserved the antioxidant activity of AA, whereas PVA showed a contrasting effect. The influence of γCD and PVA concentration on antioxidant capacity was then studied through central composite design (CCD). Even though the concentration of γCD significantly affected the inhibition efficiency of the ternary complex, the insignificant influence of PVA could not be ignored. A promising protective ternary complex should consist of an optimized concentration of PVA and a high concentration of γCD.

Intra-arterial embolotherapy for intrahepatic cholangiocarcinoma: update and future prospects

Intrahepatic cholangiocarcinoma (ICC) is a rare disease and carries a poor prognosis with surgery remaining the only curative treatment option. However, due to the late presentation of symptoms and close proximity of the tumors to central hepatic structures, only about 30% of patients are classified eligible to resection. As for palliative approaches, ICC constitutes a possible indication for loco-regional therapies (LRT). As such, intra-arterial therapies (IAT) are reported to be feasible, safe and effective in inducing tumor response in unresectable ICC. The paradigm of IAT is premised on the selective delivery of embolic, chemotherapeutic agents to the tumor via its feeding arteries, thus allowing dose escalation within the carcinoma and reduction of systemic toxicity. Conventional transcatheter arterial chemoembolization (cTACE) so far remains the most commonly used IAT modality. However, drug-eluting beads (DEB)-TACE was initiated with the idea of more selective targeting of the tumor owing to the combined embolizing as well as drug-eluting properties of the microspheres used in this setting. Moreover, radioembolization is performed by intra-arterial administration of very small spheres containing β-emitting yttrium-90 (Y90-RE) to the site of the tumor. Clinical evidence exists in support of survival benefits for IAT in the palliative treatment of ICC compared to surgery and systemic chemotherapy. As for combination regimens, cTACE, DEB-TACE and Y90-RE are reported to achieve conversion of patients to surgery in a sequential treatment planning and simultaneous IAT combinations may provide a therapeutic option for treatment escalation. Regarding the current status of literature, controlled randomized prospective trials to compare different IAT techniques and combination therapies as well as treatment recommendations for different IAT modalities are needed.

Locoregional Therapies for Primary and Secondary Hepatic Malignancies

Management of hepatic malignancies is a multidisciplinary task with the involvement of hepatologists, medical/surgical oncologists, transplant surgeons, and interventional radiologists. The patients should be selected for a specific targeted therapy after multidisciplinary consensus. Interventional oncology has established its role in the management of hepatic malignancies. Image-guided locoregional therapies decrease the rate of systemic toxicity without compromising tumoricidal effect.

Tuning stiffness of cell-laden hydrogel via host–guest interactions

We report a dynamic hydrogel system with on-demand tunable matrix stiffness.

Combination of intra-arterial therapies and sorafenib: is there a clinical benefit?

Intra-arterial therapies (IATs) play a major role in the treatment of patients with unresectable hepatocellular carcinoma. Over the last three decades, multiple loco-regional approaches such as transarterial chemoembolization or radioembolization were shown to effectively achieve local tumor control, offering significant survival benefits for selected patients with intermediate to advanced-stage disease (Barcelona Clinic Liver Cancer stage B and C). These therapies provide a dual benefit of safely delivering a highly cytotoxic payload directly to the tumor while reducing systemic toxicity. This capability maintained the advantage of IATs over conventional systemic chemotherapy. The introduction of sorafenib as a systemically applicable drug, the first of its kind to provide survival benefits by means of oral monotherapy, contributed to a paradigm change. The idea of combining this novel agent with IATs seemed intriguing, and a variety of national and international clinical trials were initiated to explore the potential benefits of this exciting new option. A plethora of preliminary data has been made available throughout the last 5 years, and the interpretation of the inhomogeneously designed protocols proved difficult. In this review, we will provide a brief state-of-the-art update on the most frequently used intra-arterial modalities and discuss the molecular mechanism, potential biomarkers as well as the safety profile of sorafenib. Furthermore, we will discuss the role of the sequence of administration in combined therapies. Finally, this review will examine the evidence for clinical outcomes for the combination of different IATs with sorafenib.

Intraarterial therapies for primary liver cancer: state of the art

Image-guided intraarterial therapies play an important role in the treatment of patients with hepatic malignancies. These therapies provide the dual benefit of reduced systemic toxicity and effective local tumor control. As a result, procedures such as transarterial chemoembolization have been included in the official treatment guidelines for hepatocellular carcinoma (HCC) and are fully accepted for the treatment of patients with intermediate stage disease. In this review, we will describe the scientific rationale for intraarterial therapies and discuss the available clinical evidence for primary liver cancer. Finally, we will touch on the current trends consisting of combining intraarterial approaches with systemically administered targeted agents.

Chemoembolization and radioembolization for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) continues to represent a major worldwide problem. Although treatments such as resection, transplantation, and ablation may provide a chance for a cure, these options are often precluded because of advanced disease presentation. Palliative treatments include transarterial embolization and systemic therapies. This review will summarize the state of the science for embolic therapies in HCC (conventional and drug-eluting chemoembolization, radioembolization) as well as discuss related topics including HCC staging, assessment of response, and ongoing clinical trials.

Formulation optimization of sustained-release ammonio methacrylate copolymer microspheres. Effects of log p and concentration of polar cosolvents, and role of the drug/copolymer ratio

The objectives of this work were the formulation optimization of the preparation process parameters and to evaluate spray-dried sustained-release microspheres using ammonio methacrylate copolymer (AMC) as a polymer matrix. The effects of log P and the concentrations of the cosolvents (acetone, methyl ethyl ketone and n-butyl acetate) and different drug/copolymer ratios as independent variables on the physicochemical parameters (the W1/O emulsion viscosity, the microsphere production yield, the average particle size, the encapsulation efficiency) and the cumulative in vitro drug release as dependent variables were studied. The optimization was carried out on the basis of the 33 factorial design study. The optimization process results showed that addition of polar cosolvents proved effective, linear relationships were observed between the independent and the dependent variables. The best conditions were achieved by microspheres prepared by using a low/medium cosolvent log P, cosolvent concentration of 25-50% v/v and a drug/copolymer ratio of 1:16. The microspheres ensured sustained release with Nernst and Baker-Lonsdale release profiles.

Formulation and drying of alginate beads for controlled release and stabilization of invertase

Several alternatives to the conventional alginate beads formulation were studied for encapsulation of invertase. Pectin was added to the alginate/enzyme solution while trehalose and β-cyclodextrin were added to the calcium gelation media. The effect of composition changes, freezing, drying methods (freeze, vacuum, or air drying), and thermal treatment were evaluated on invertase stability and its release kinetics from beads. The enzyme release mechanism from wet beads depended on pH. The addition of trehalose, pectin, and β-cyclodextrin modified the bead structure, leading in some cases to a release mechanism that included the relaxation of the polymer chains, besides Fickian diffusion. Enzyme release from vacuum-dried beads was much faster than from freeze-dried beads, probably due to their higher pore size. The inclusion of β-cyclodextrin and especially of pectin prevented enzyme activity losses during bead generation, and trehalose addition was fundamental for achieving adequate invertase protection during freezing, drying, and thermal treatment. Present results showed that several alternatives such as drying method, composition, as well as pH of the relese medium can be managed to control enzyme release.

Chemoembolization agents for cancer treatment

Chemoembolization has been used in the field of interventional oncology. Although practiced widely, it has only recently been demonstrated that the use of transarterial chemoembolization (TACE) provides a survival benefit based on randomized controlled trials. TACE combines the effect of targeted chemotherapy with the effect of ischemic necrosis induced by arterial embolization. Most of the TACE procedures have been based on iodized oil utilizing its microembolic and drug-carrying characteristics. Recently, there have been efforts to improve the delivery of chemotherapeutic agents to a tumor, which leads to the development of drug-eluting particles. In this review, we will describe the properties and efficacy of some chemoembolization agents which are commercially available and/or currently under clinical investigations. The potential and future of this new form of transcatheter arterial therapy for liver cancer will be discussed.

Transcatheter intraarterial therapies: rationale and overview

Transcatheter intraarterial therapies have proved valuable in the battle against primary and secondary hepatic malignancies. The unique aspects of all such therapies are their reduced toxicity profiles and highly effective tumor responses. These unique characteristics coupled with their minimally invasive nature provide an attractive therapeutic option in patients who may have previously had few alternatives. The concept of all catheter-based intraarterial therapies is to selectively deliver anticancer treatment to tumor(s). These therapies, which include transarterial embolization, intraarterial chemoinfusion, transarterial chemoembolization with or without drug-eluting beads, and radioembolization with use of yttrium 90, inflict lethal insult to tumors while preserving normal hepatic parenchyma. This is possible because hepatic neoplasms preferentially derive their blood supply from an arterial source while the majority of noncancerous liver is supplied by the portal vein. As part of the interventional oncology review series, in this article we describe the rationale behind each of these transcatheter therapies and provide a review of the existing medical literature.

Surface modified activated carbon with β-cyclodextrin--Part I. Synthesis and characterization

Surface functional groups produced from oxidation (carboxylic acid, lactone, quinine, phenol, and nitro groups), reduction (alcohol and amine groups), and grafting (imine and hemi-acetal) reactions were characterized (using surface analysis and chemical methods) and compared with unmodified activated carbon (AC) materials. The untreated, surface-modified, and grafted activated carbon materials were characterized by various surface sensitive methods: Diffuse Reflectance Infrared Fourier Transform Spectroscopy, Scanning Electron Microscopy, Raman spectroscopy, thermogravimetry analysis, and Matrix Assisted Laser Desorption Ionization Time of Flight (MALDI-TOF) mass spectrometry. A chemical method (Boehm titration) was used for estimating the amount of surface bound acidic and basic functional groups. Nitrogen porosimetry was used to analyze the surface area (95-1350 m²/g) and pore volume (0-0.31 cm³/g) characteristics of AC, surface modified AC, and AC materials grafted with β-cyclodextrin.

Poly(vinyl alcohol) microspheres with pH- and thermosensitive properties as temperature-controlled drug delivery

One of the most important inconveniences of the pH- and temperature-sensitive hydrogels is the loss of thermosensitivity when relatively large amounts of a pH-sensitive monomer are co-polymerized with N-isopropylacrylamide (NIPAAm). In order to overcome this drawback, we propose here a method to prepare thermosensitive poly(vinyl alcohol) (PVA) microspheres with a higher content of carboxylic groups that preserve thermosensitive properties. Moreover, PVA possesses excellent mechanical properties, biocompatibility and non-toxicity. PVA microspheres were obtained by suspension cross-linking of an acidified aqueous solution of the polymer with glutaraldehyde. Poly(N-isopropylacrylamide-co-N-hydroxymethyl acrylamide) (poly(NIPAAm-co-HMAAm)), designed to have a lower critical solution temperature (LCST) corresponding to that of the human body, was grafted onto PVA microspheres in order to confer them with thermosensitivity. Then, the pH-sensitive functional groups (COOH) were introduced by reaction between the un-grafted OH groups of PVA and succinic anhydride. The pH- and temperature-sensitive PVA microspheres display a sharp volume transition under physiological conditions around the LCST of the linear polymer. The microspheres possess good drug-loading capacity without losing their thermosensitive properties. Under simulated physiological conditions, the release of drugs is controlled by temperature.

PVA hydrogels containing beta-cyclodextrin for enhanced loading and sustained release of ocular therapeutics

The purpose of this work is to develop poly(vinyl alcohol) (PVA) hydrogels incorporating large amounts of beta-cyclodextrin (beta-CD) in order to improve ocular drug loading and to sustain drug release. First, the mono-methacrylated-beta-CD monomer (MA-beta-CD) and the methacrylated-PVA macromer (PVAMA), with a substitution degree of 7%, are synthesized and characterized. Then, the poly(methacrylated-PVA-co-mono-methacrylated-beta-cyclodextrin) (pPVA-beta-CD) hydrogels are prepared by UV-induced polymerization of MA-beta-CD and PVAMA. The highest amount of beta-CD incorporated into the hydrogels is 30 wt%. The hydrogels are further characterized by transmittance, FT-IR, equilibrium swelling ratio (ESR), tensile tests and protein deposition. The results show that pPVA-beta-CD hydrogels possess good transmittance, while the incorporation of beta-CD in the hydrogels improves the tensile strength and decreases the ESR and protein deposition. Finally, puerarin and acetazolamide are used as models to evaluate the drug loading and in vitro release behavior of the pPVA-beta-CD hydrogels. The results indicate that the amount of drug loaded into the pPVA-beta-CD hydrogels progressively increases, while the release rate decreases with increasing beta-CD content. In particular, incorporation of beta-CD efficiently decreases the initial burst release of acetazolamide, while the release, which is almost linear, is sustained for 15 days. The pPVA-beta-CD hydrogels have potential applications as biomedical devices for sustained release of ocular drugs.

Chemoembolization for primary and metastatic liver cancer

Transcatheter arterial chemoembolization (TACE) is one of the most commonly performed procedures in interventional radiology and is currently used for the palliative treatment of primary and metastatic hepatic malignancies. A new type of TACE is TACE with drug-eluting microspheres, which is currently gaining wide acceptance worldwide. In this article, we will review some technical components, patient selection, current results, and future directions of TACE and TACE with drug-eluting microspheres for primary and metastatic liver cancer.

Intra-arterial therapies for hepatocellular carcinoma: where do we stand?

PURPOSE AND DESIGN

Intra-arterial therapies for unresectable hepatocellular carcinoma (HCC) consist of a catheter-based group of treatments where therapeutic and/or embolic agents are intra-arterially directed to target tumors. Here we review these therapies, which may be classified into embolotherapy/chemotherapy-based and radiotherapy-based treatments. Embolotherapy/chemotherapy-based treatments include transcatheter arterial embolization, transarterial chemoembolization, transcatheter arterial chemoeinfusion, and chemoembolization with drug-eluting beads. Radiotherapy-based treatments include radioembolization with yttrium-90 and injection of iodine-131-labeled lipiodol.

RESULTS AND CONCLUSION

Interpretation of the results of clinical trials as well as implementation of meta-analyses involving the efficacy of intra-arterial therapies for unresectable HCC has been challenging and difficult to perform. The levels of evidence for treatment recommendations in oncology provide a common framework to understand the current status of intra-arterial therapies for HCC. Here we use an evidence-based approach to critically review and comprehend the current role and future potential of intra-arterial therapies in unresectable HCC.

Embolotherapy in the management of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) ranks fifth in frequency of cancers worldwide. The incidence of HCC in the United States is rising, primarily due to the number of patients who were infected by hepatitis in the 1960s and 1970s coupled with the rising migrant population from Asia, where hepatitis is widely prevalent. Up to 80% of the patients present with multicentric HCC and advanced liver disease or comorbidities that restrict the option of resection or liver transplantation. The dual blood supply (arterial and portal) to the liver with predominantly arterial supply to the tumor has made embolotherapy a cornerstone in the management of inoperable HCC. The techniques have become refined not only due to the development of microcatheter angiographic capabilities, but also in the ability to deliver a wide variety of therapeutic agents to these tumors. This article reviews the fundamental principles of bland embolization, chemoembolization, and radioembolization in the management of HCC.

Transcatheter and ablative therapeutic approaches for solid malignancies

The purpose of this article is to present in a concise manner an overview of the most widely used locoregional transcatheter and ablative therapies for solid malignancies. An extensive MEDLINE search was performed for this review. Therapies used for liver cancer were emphasized because these therapies are used most commonly in the liver. Applications in pulmonary, renal, and bone tumors were also discussed. These approaches were divided into catheter-based therapies (such as transcatheter arterial chemoembolization, bland embolization, and the most recent transcatheter arterial approach with drug-eluting microspheres), ablative therapies (such as chemical [ethanol or acetic acid injection]), and thermal ablative therapies (such as radiofrequency ablation, laser induced thermotherapy, microwave ablation, cryoablation, and extracorporeal high-intensity focused ultrasound ablation). A brief description of each technique and analysis of available data was reported for all therapies. Locoregional transcatheter and ablative therapies continue to be used mostly for palliation, but have also been used with curative intent. A growing body of evidence suggests clear survival benefit, excellent results regarding local tumor control, and improved quality of life. Clinical trials are underway to validate these results. Image-guided transcatheter and ablative approaches currently play an important role in the management of patients with various types of cancer-a role that is likely to grow even more given the technological advances in imaging, image-guidance systems, catheters, ablative tools, and drug delivery systems. As a result, the outcomes of patients with cancer undoubtedly will improve.

Technology insight: Image-guided therapies for hepatocellular carcinoma--intra-arterial and ablative techniques

Locoregional techniques have become the mainstay of therapy for patients with unresectable hepatocellular carcinoma (HCC). Such image-guided interventions include catheter-based approaches (transarterial chemoembolization and yttrium-90 radiotherapy) and locoregional ablative techniques, either chemical (percutaneous ethanol injection), or thermal (radiofrequency ablation, laser ablation, microwave ablation and cryoablation). These therapies are mainly utilized for palliation, but have also been used with curative intent. In selected cases, percutaneous interventional treatments have shown good results (5-year survival 40-50%), but, even when chosen as first-line treatment, have not been able to achieve the response rates and outcomes achieved by surgical options (resection or transplantation). New promising image-guided therapies are continuously emerging, as we attempt to improve tumor targeting, minimize hepatic toxicity and ultimately improve quality of life and survival of patients with HCC. With new technologies in imaging and drug delivery becoming available, it is likely that, in the future, patients with HCC will be best treated by a multidisciplinary team approach, utilizing a combination of techniques to improve patient survival. This review outlines the current status of the most commonly used image-guided locoregional interventions in the treatment of patients with HCC, and describes recent research and advances related to image-guided interventions for liver cancer.

Retarded dissolution of ibuprofen in gelatin microcapsule by cross-linking with glutaradehyde

Ibuprofen-loaded gelatin microcapsule, a solid form of microcapsules simultaneously containing ethanol and ibuprofen in water-soluble gelatin shell was previously reported to improve the dissolution of drug. In this study, to retard the initial high dissolution of ibuprofen from gelatin microcapsule, the ibuprofen-loaded cross-linked gelatin microcapsule was prepared by treating an ibuprofen-loaded gelatin microcapsule with glutaraldehyde and its dissolution was evaluated compared to ibuprofen powder and gelatin microcapsule. The ibuprofen-loaded cross-linked microcapsule treated with glutaraldehyde for 10 and 60 sec gave significantly higher dissolution rates than did ibuprofen powder. Furthermore, the dissolution rate of ibuprofen from the cross-linked microcapsule treated for 10 sec was similar to that from gelatin microcapsule. However, the dissolution rate of ibuprofen from the cross-linked microcapsule treated for 60 sec decreased significantly compared to gelatin microcapsule, suggesting that the treatment of gelatin microcapsule with glutaraldehyde for 60 sec could cross-link the gelatin microcapsule. Furthermore, the cross-linking of gelatin microcapsule markedly retarded the release rate of ibuprofen in pH 1.2 simulated gastric fluid compared to gelatin microcapsule. However, the cross-linking of gelatin microcapsule with glutaraldehyde hardly changed the size of gelatin microcapsules, ethanol and ibuprofen contents encapsulated in gelatin microcapsule. Thus, the ibuprofen-loaded cross-linked gelatin microcapsule could retard the initial high dissolution of poorly water-soluble ibuprofen.

Effects of conditions for preparing nanoparticles composed of aminoethylcarbamoyl-β-cyclodextrin and ethylene glycol diglycidyl ether on trap efficiency of a guest molecule

Nanoparticles comprising copolymers of aminoethylcarbamoyl-beta-cyclodextrin (AEC-beta-CD) and ethylene glycol diglycidyl ether (EGDGE) are prepared by an interfacial polyaddition reaction in a miniemulsion system. Polymers are formed in a W/O emulsion containing 0.25-10.0% (w/w) water and 5.0% (w/w) surfactant (MO-3S, tetraglycerin monoester, HLB 8.8), where simple particles are predominantly obtained when the water content is 1.0% and 5.0%. Notably, nano-size small particles (diameter: 0.3 microm) are formed under the condition of 5.0% water and 5.0% surfactant, which have the highest beta-CD contents (75.5 wt.%) and the most positive zeta-potential (53.6 mV). The zeta-potential measurement indicates that the obtained particles have positive charge due to protonation of their amino groups below around pH 10. Actually, uptake of 8-anilino-1-naphthalenesulfonic acid (ANS) bearing negative charge (SO(3)(-)) and moderate hydrophobicity depends on the magnitude of zeta-potential of the particles; viz., the particles with zeta-potential of 53.6 mV show the highest efficiency of uptake. The diameter and the beta-CD contents are closely related with the water/surfactant ratio, and the zeta-potentials are dependent on both the diameter and the beta-CD contents. Inclusion of ANS into the CD cavity of EGDGE/AEC-beta-CD particles can be controlled by electrostatic interaction between ANS (negatively charged) and the particle (positively charged). Namely, synergistic effect of cavity-inclusion and electrostatic interaction can dominate the uptake of guest molecules by the particles.

Cyclodextrins in drug delivery: an updated review

The purpose of this review is to discuss and summarize some of the interesting findings and applications of cyclodextrins (CDs) and their derivatives in different areas of drug delivery, particularly in protein and peptide drug delivery and gene delivery. The article highlights important CD applications in the design of various novel delivery systems like liposomes, microspheres, microcapsules, and nanoparticles. In addition to their well-known effects on drug solubility and dissolution, bioavailability, safety, and stability, their use as excipients in drug formulation are also discussed in this article. The article also focuses on various factors influencing inclusion complex formation because an understanding of the same is necessary for proper handling of these versatile materials. Some important considerations in selecting CDs in drug formulation such as their commercial availability, regulatory status, and patent status are also summarized. CDs, because of their continuing ability to find several novel applications in drug delivery, are expected to solve many problems associated with the delivery of different novel drugs through different delivery routes.