Recent Advances in Solid Dispersion Technology for Efficient Delivery of Poorly Water-Soluble Drugs

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.