Recent Patents on Nanomedicine - Volume 5, Issue 2, 2015

Hydrophobic drug entities are the major challenges for pharmaceutical scientists to deliver through oral route of administration due to limited drug solubility and bioavailability particularly emerged from combinatorial chemistry and computer aided drug design. Presently, self-emulsifying systems have been employed as the most common approach for delivery of numerous poor aqueous drugs. This unique strategy exploits many lipids, surfactants, co-surfactants and permeation enhancers to form an ideal isotropic mixture in water or gastric fluid by gentle agitation. The chapter attempts to explore components of SEDDS in designing of drug delivery system to accommodate significant amount of poorly soluble drugs, limitations of the system and their rectification, types of SEDDS, evaluation of SEDDS and a short review of research in last decade involved to improve oral bioavailability of drugs. The aim of this chapter is a throughout understanding of lipid based dosage form designing and application in self-emulsifying drug delivery system from enhanced oral bioavailability point of view for drugs possessing water solubility problem. Moreover, the present article would also provide a brief account of the patent instances filed/approved in this domain for providing an updated account of the concept.

Conventional drug delivery systems are related with drug, carrier and the route of administration based limitations as compared to novel drug delivery systems. Presently, nanolipid based carriers are the most appropriate delivery systems for poorly soluble drugs to improve the solubility of drugs and eventually oral bioavailability. Polymeric nanoparticles face some inherent drawback owing to its chemical properties such as limited drug loading, poor stability on prolonged standing and toxicity related issues while chronic treatment. However, nanostructued lipid carriers are the second generation lipid nanoparticles composed of biocompatible, biodegradable, non-toxic and physiologically compatible lipids for oral administration. The system for lipophilic drugs is the excellent and offered several advantages over polymeric carriers. It is well known that lipophilic compound is more soluble in lipid and capable to deliver more significantly across the mucosal membrane through the oral route. This enhances oral bioavailability of these challengeable molecules with lipid based nanostructured lipid carrier as compared to conventional dosage form and others drug delivery system. This carrier employs lipid to incorporate drug (s) in high percent and toxicity concern are minimum in comparison to polymeric carriers. The present chapter aimed to explore the attempts and approaches in order to enhance the solubility of poorly aqueous soluble drug for improved oral BA along-with comparative study of toxicity issues related to drug and carrier in the light of literature reports including select instances of patents for providing an updated account to the pharmaceutical scientists working in the domain of nanostructured lipid carriers.

Lipid-Drug Conjugate (LDC) is an emerging field of nanotechnology which has potential applications in delivery of drugs and targeting them to specific site. Several molecules were supposed as promising and good therapeutic candidates during in vitro studies but they failed during in vivo studies showing the limited oral bioavailability as a major dilemma. LDC technological based approach played a vital role in augmenting bioavailability of such drug candidates. In LDC system, lipids such as fatty acids, diglycerieds, triglycerides and phophoglycerides covalently bind with drug molecule for improved lipophilic character of drug. This could lead to better penetration and absorption through biological membrane which ultimately enhances the bioavailability of the corresponding therapeutic agent. Drugs including phenytoin, beta lactum antibiotics, noscapine, valproic acid, non-steroidal anti-inflammatory drugs (ibuprofen) were successfully linked through covalent bond by different lipid carriers which improved their physicochemical properties, intestinal absorption and target specificity. This chapter extensively reviewed the lipidic and glycolipidic conjugates of various drugs which enhanced the bioavailability compared to free drug solution exploring that such LCD technique can be used for the enhancement of bioavailability of poorly aqueous soluble drugs. The chapter included several patents with informative results which would help for pharmaceutical scientist working this area.

Lipid-based drug delivery systems (LBDDS) are one of the most promising delivery systems for several drugs with poor solubility and bioavailability after administration through oral route and other routes of administration. A variety of drug candidates seek lipid based delivery owing to increased solubility and other benefits as discussed drug-wise in this chapter elsewhere. It is noteworthy that lipid based drug delivery is considered as innovative and acceptable strategy as compared to polymeric nanoparticles in terms of highest drug loading, easy to scale-up on commercial scale in industries, being biocompatible and free from organic solvent in the finished product. Recently, several biological macromolecules are delivered successfully in lipid based formulations to protect them from intestinal enzymatic degradation, to improve solubility, to enhance bioavailability and to commercialize easily. In this chapter, we focused delivery of several therapeutic biological macromolecules which are facing problems in the formulation designing with enhanced efficacy and in vivo performance. These systems consist of diverse group of formulations, each consisting of varying functional and structural properties that are amenable to modifications achieved by varying the composition of lipid excipients and other additives. These systems are basically solid lipid particulate dosage forms, nanoemulsion, nanostructured lipid carrier, and vesicular systems. Thus, this chapter conclusively gives the advances in LBDDS for diverse biological macromolecules. Moreover, the present article would also provide a brief account of the patent instances filed/approved in this domain for providing an updated account of the concept.

A variety of potent lipophilic drugs exhibits low oral bioavailability due to poor water solubility of drugs. These drugs are challenging for the formulation scientists with regard to solubility and bioavailability (BA). Extensive efforts are ongoing to enhance oral BA of these types of drugs to increase clinical efficacies. The most common approach is the use of highly developed lipid-based drug delivery systems. This is a strategy to incorporate drug into the safe and biodegradable lipids (natural, semi-synthetic, vegetable oils or hydrolyzed solid lipids) with improved oral bioavailability. Lipid microparticles (LM) are efficient lipid based drug delivery system which might be prudent attempt to increase the oral bioavailability of poor aqueous soluble drugs. Lipid based systems are recognized as a potential approach for the improved oral absorption which ultimately caused to enhanced BA. Wide variety and range of substances have been reported to be entrapped into lipid microparticles including lipophilic and hydrophilic molecules as well as labile proteins and peptides. Moreover, LM can protect drugs from in vitro and in vivo degradation. Several authors reported numerous techniques and methods to enhance drug solubility by exploiting lipids while formulation development. The use of LM is a novel carrier to enhance oral BA of poor aqueous soluble drug. Lipids are well known to deliver a number of drugs with profound systemic availability either through portal vein or lymphatic absorption from gastro-intestinal tract. These lipids are belonging to triglycerides (short chain, medium chain and long chain) with or without double bond in their hydrocarbon chain length. The present chapter discusses the physico-chemical properties, processing techniques necessary to obtain lipid-based microparticles formulations for oral delivery along with a brief discussion of lipid excipients and their characterization. The chapter provided related patents with valuable informations for pharmaceutical research groups which would be very informative and instructive.

Rheumatoid arthritis (RA) is an immune mediated joint based dreadful inflammatory disorder, which is characterized by joint destruction, swelling, pain and remission; it resulted to shorten lifespan and increased mortality rates. Current treatment approaches and their advancement have gained much attention in the prevention of RA and improvement in the many RA patients life. Despite their significant merits, still major drawbacks remain like requirement of high dose, disease remission and prominent side effects. Emergences of lipid based vesicular nanocarriers, including liposomes, stealth liposomes, transfersomes, ethosomes, and niosomes etc., are designed to deliver anti-rheumatic drug to the specific sites via enhanced permeability and retention (EPR) and active targeting to achieve desirable therapeutic effect. Whereas it avoids systemic and non target associated side effects. In addition to this, several US and others patents on liposomes in RA are also included. Therefore, the present review gives an exhaustive account on recent advancement in lipid containing vesicular nanocarrier’s drug delivery in the treatment of RA.

IBD significantly affects the young population around the globe as the statistical reports worldwide showing the threatening growth in the IBD individuals and patients. The etiology and pathophysiology of the IBD are unclear and the causes of disease are also multifactorial. Identification, maintenance and management of the disease is a challenging aspect. This review focuses on various modern concepts revealed in the treatment of IBD. The drug therapies such as aminosalicylates, Immunomodulators, probiotics, antibiotics are used in the treatment of IBD but the choice of the drug and the combination of the drugs play a crucial role in the successful management of IBD. The various nano drug delivery systems are under extensive research throughout the world since these drug delivery systems are found successful in the treatment of IBD due to their nanosize and targeting to the inflamed sites. In the past one decade, there were several patents that were registered and approved in IBD related issues and the use of drug delivery system in the treatment of IBD. In this article various patents were consolidated in areas such as IBD related issues and nano drug deliveries in the treatment of IBD. The industrial concept and status of drug delivery system are also discussed briefly. Other important factors such as natural remedies, microscopic colitis, upcoming drugs and treatment methods related information are also critically presented in this article.