Drug discovery is generally considered as a costly affair and it takes approximately 15 years to reach a new chemical entity into the market. Among the recent potent drug molecules with most effective pharmacological properties, very few reached for Phase I clinical trial in humans. Unfortunately, the historical average reveals an almost 90% overall attrition rate in clinical trials. The solubility and permeability of a drug are the critical factors influencing the success of a drug. Oral drug delivery systems still continue to exist as the most favored, simplest and easiest administration route. A huge number of potential clinical candidates won’t make it to the market or accomplish their maximum capacity except if their solubility and oral bioavailability are enhanced by formulation. The solubility of drugs will continue to exist as important aspects of formulation development. With the emergence of synthetic methods for new molecule synthesis in chemistry and better screening methods, the number of poorly water soluble compounds has dramatically expanded in the last few years. Solid dispersion is one of the most important techniques as it can be prepared by several methods. It is mostly prepared with a drug having poor water solubility and it explores hydrophilic polymers either individually or in combination for the enhancement of solubility. In comparison to the conventional formulations such as tablets or capsules, there are different methods with which solid dispersions can be prepared and also have many benefits over conventional drug delivery approaches. Solid dispersion systems are potential for increasing the solubility, oral absorption and bioavailability of drugs and the significance of the solid dispersion technology is constantly increasing. The main focus of this review is to present recent advancements in the area of solid dispersion. This review also includes an account of recent patents on solid dispersion and clinical status of solid dispersion based formulations.
The oral route is the most preferred delivery route for drug administration due to its advantages such as lower cost, improved patient compliance, no need for trained personnel and the drug reactions are generally less severe. The major problem with new molecules in the drug discovery pipeline is poor solubility and dissolution rate that ultimately results in low oral bioavailability. Numerous techniques are available for solubility and bioavailability (BA) enhancement, but out of all, solid dispersion (SD) is proven to be the most feasible due to the least issues in manufacturing, processing, storage, and transportation. In the past few years, SD had been extensively applied to reinforce the common issues of insoluble drugs. Currently, many hydrophobic and hydrophilic polymers are used to prepare either immediate release or controlled release SDs. Therefore, the biological behavior of the SDs is contingent upon the use of appropriate polymeric carriers and methods of preparation. The exploration of novel carriers and methodologies in SD technology leads to improved BA and therapeutic effectiveness. Moreover, the clinical applicability of SD-based formulations has been increased with the discovery of novel polymeric carriers. In this review, emphasis is laid down on the present status of recent generations of SDs (i.e., surfactant and controlled release polymer-based SD) and their application in modifying the physical properties of the drug and modulation of pharmacological response in different ailments.
A redox-responsive macromolecular prodrug of tacrolimus, HA-ss-Tac, was constructed by conjugation of tacrolimus (TAC, FK506) through its succinate ester to cystamine-modified hyaluronic acid (HA-Cys), and its physicochemical properties and immunosuppressive activity were studied. The synthesized HA-ss-TAC was determined to contain 8% of chemically loaded TAC with significantly enhanced water solubility. The release study showed a sustained release of drug through slow degradation of linker−drug bonds. In vitro inhibition of proliferation of T-and B-lymphocytes was almost comparable to that of TAC, implying that the biologically active compound could be released from the conjugate. The polymeric prodrug lacks obvious cytotoxicity on Raw 264.7 macrophages and significantly suppressed the production of inflammatory cytokines IL-2 and IL-1β by LPS-activated cells. Additionally, the cellular uptake study of the FITC-labeled conjugate confirmed the HA receptor-mediated internalization of the conjugate into targeted cells, thus avoiding systemic side effects. Taken together, the HA-ss-TAC prodrug could be an optimal prodrug for intravenous administration based on this preliminary data and can be expected to have improved therapeutic efficacy.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.