Recent Patents on Drug Delivery & Formulation (v.5, #1)

Recent Advances in Intraocular Drug Delivery Systems by Tsutomu Yasukawa, Yasuhiko Tabata, Hideya Kimura, Yuichiro Ogura (1-10).
Vitreoretinal diseases are refractory to both topical and systemic pharmacological approaches because of specific environment of the eye. That is, the cornea, the sclera, nasolacrimal drainage of tears, frontward stream of aqueous humor, blood-aqueous barrier, and blood-retinal barrier strictly limit penetration and diffusion of drug into the retina. However, recent advances in intraocular drug delivery systems (DDS) have enabled drug to be delivered effectively into the eye. Clinically successful or promising cases involve non-biodegradable implants and inserts, biodegradable inserts and microparticles, intravitreal or sub-Tenon's injection of triamcinolone acetonide, and a photodynamic therapy (PDT) with verteporfin, a photosensitizer. More recently, a variety of pharmacological challenges to treat exudative age-related macular degeneration and macular edema are proceeding into clinical trials, as soon as antivascular endothelial growth factor (anti-VEGF) therapies have been proved to be effective by repeated intravitreal injections. In the near future, DDS must be required not only to develop a new treatment modality but also to improve efficacy and/or reduce injection numbers of currently available drugs. Here we introduce controlled release of drug and discussion of recent patents with biodegradable or non-biodegradable implants and drug targeting by modification of systemically administered drug.

Review of Patents on Microneedle Applicators by Thakur R.R. Singh, Nicholas J. Dunne, Eoin Cunningham, Ryan F. Donnelly (11-23).
Transdermal drug delivery offers certain advantages over conventional oral or parenteral administration. However, transdermal delivery is not available to many promising therapeutic agents, especially high molecular weight hydrophilic compounds. This is due to the excellent barrier property of the superficial skin layer, the stratum corneum (SC). Only drugs with very specific physicochemical properties (molecular weight andlt; 500 Da, adequate lipophilicity, and low melting point) can be successfully administered transdermally. Of the several active approaches used to enhance the transport of drugs through the SC, the use of microneedles (MNs) has recently been shown to be very promising and has attracted considerable attention by researchers from both industry and academia. MNs, when used to puncture skin, will by-pass the SC and create transient aqueous transport pathways of micron dimensions and enhance the transdermal permeability. However, for effective performance of these MNs in drug delivery applications, irrespective of the type, material, height and density, it is imperative that they penetrate into the skin with the greatest possible accuracy and reproducibility. Due to the inherent elasticity and irregular surface topography of the skin, it remains a major challenge to the reproducibility of MN penetration. Therefore, in order to achieve uniform and reproducible MN penetration into skin, an external source of assistance could be very useful. Accordingly, this review deals with various innovative applicator designs developed by industry and research centres in the context of effective application of MN arrays for transdermal drug delivery, as disclosed in the recent patent literature.

Self-Assembling Peptides: Implications for Patenting in Drug Delivery and Tissue Engineering by Pradeep Kumar, Viness Pillay, Girish Modi, Yahya E. Choonara, Lisa C. du Toit, Dinesh Naidoo (24-51).
In this paper, a comprehensive review of recent patents concerning the molecular self-assembly of peptides, peptide amphiphiles and peptidomimetics into molecules through nanoarchitectures to hydrogels is provided. Their potential applications in the field of drug delivery and tissue engineering have been highlighted. The design rules of this rapidly growing field are centered mainly on the construction of peptides in the form of peptide amphiphiles, aromatic short peptide derivatives, all-amino acid peptide amphiphiles, lipidated peptides with single and multiple alkyl chains and peptide-based block copolymers and polymer peptide conjugates. The interest in patenting of self-assembling peptides is also driven by their type (I, II, III and IV) and their ability to form well-regulated highly-ordered structures such as and#946;- sheets/and#946;-hairpins, and#945;-helices/coiled coils and to hierarchically self-organize into supra-molecular structures. The applicability of these systems in cell culture scaffolds for tissue engineering, drug and gene delivery and as templates for nanofabrication and biomineralization has inspired various groups over the globe. This resulted in development of selfassembling peptides as synthetic replacements of biological tissues, designing materials for specific medical applications, and materials for new applications such as diagnostic technologies. Furthermore, biologically derived and commercially available systems are also discussed herein along with a brief account of various awarded and pending patents in the past 10 years. An overview of the diversity of the patent applications is also provided for self-assembling systems based on nano- and/or micro-scale such as fibers, fibrils, gels, hydrogels, vesicles, particles, micelles, bilayers and scaffolds.

Recent Patents on Oral Combination Drug Delivery and Formulations by Praveen S. Hiremath, Shrikant A. Bhonsle, Sridhar Thumma, Viswatej Vemulapalli (52-60).
Oral combination drug delivery systems have been proven to be highly beneficial and vital in the treatment of several dreadful diseases such as cancer, HIV (AIDS) and tuberculosis. Further, pharmaceutical companies have often explored the strategy of combination drug therapy for treating diseases such as diabetes (Type 2), cardiovascular diseases, central nervous system (CNS) disorders, and for treating several other microbial infections. Patenting combination drug delivery systems and formulations has been proven to be very beneficial for the sustainment and growth of pharmaceutical industry. Several pharmaceutical companies have explored this opportunity in extending the life cycle of their blockbuster molecules, and providing additional sources of revenues when the new chemical entity (NCE) discovery is scarce. The article reviews some recent combination formulation patents and patent publications, particularly the US patents and patent applications, relevant to oral delivery of pharmaceuticals. Examples of some oral combination products on the US and worldwide market are presented. Patents and patent applications on combination oral formulations relevant to analgesics (including anti-inflammatory and antipyretics), cardiovascular system (CVS) products, antibacterial and antiviral, and central nervous system (CNS) products are briefly discussed.

Pelletization Processes for Pharmaceutical Applications: A Patent Review by Stavros N. Politis, Dimitrios M. Rekkas (61-78).
Pellets exhibit major therapeutic and technical advantages which have established them as an exceptionally useful dosage form. A plethora of processes and materials is available for the production of pellets, which practically allows inexhaustible configurations contributing to the flexibility and versatility of pellets as drug delivery systems. The scope of this review is to summarize the recent literature on pelletization processes for pharmaceutical applications, focusing on the awarded and pending patents in this technical field. The first part of the article provides an overview of innovation in pelletization processes, while the second part evaluates their novel applications.

Patent Selections: by Bentham Science Publishers (79-81).
The patents annotated in this section have been selected from various patent databases. These recent patents are relevant to the articles published in this journal issue, categorized by therapeutic areas/targets and therapeutic agents related to drug delivery and formulations.