HDDS™, Acusphere's Hydrophobic Drug Delivery System
Broad Applications for the Delivery of Hydrophobic Drugs.
We have developed a proprietary formulation technology called HDDS™ that converts drugs that do not dissolve well in water, or hydrophobic drugs, into microparticles or nanoparticles of the drug embedded in small microspheres, such that the drug can more rapidly dissolve in water. Formulation of hydrophobic drugs is often challenging since the human body is primarily composed of water. Therefore, hydrophobic drugs do not dissolve well in the body, which can limit the effectiveness of these drugs.
Many promising drugs never make it to market because they are difficult to dissolve or have less than ideal formulations. Drug programs have been abandoned after significant investment because suitable formulations for these insoluble drugs are elusive. Developing intravenous formulations of hydrophobic drugs is particularly difficult. Additionally, intravenous formulations can expand the market for the oral dosage formulation because physicians typically prefer to discharge patients on the oral formulation of the intravenous formulation administered to the patient while in the hospital.
Many hydrophobic drugs are comprised of particles that are relatively large and therefore have a limited surface area available for interaction with water. These hydrophobic drugs are often formulated in less than ideal ways in order to make them dissolve. It is possible to increase the dissolution rate of some hydrophobic drugs by increasing their aggregate surface area. To accomplish this, many pharmaceutical companies use a process called micronization, which entails grinding hydrophobic drugs into smaller microspheres. However, the drug particles produced by micronization are often still not small enough to adequately improve dissolution, or to be administered intravenously. Alternatively, oils like Cremophor® are used as solvents. However, these solvents are often-times not well tolerated and can require prolonged infusion rather than rapid injections to minimize potential adverse side effects. Sometimes development of hydrophobic drugs must be terminated because no suitable formulation can be found.
We have demonstrated in pre-clinical studies that our HDDS™ technology may improve the dissolution rate of a variety of hydrophobic drugs, achieving up to 30-fold increases in dissolution rates that are well tolerated. We believe that these drug formulations would be suitable for all routes of administration without resorting to the use of unsafe or less than ideal additives to formulate the drug. Acusphere's initial clinical human proof of HDDS™ Concept is AI-850™, a reformulation of the hydrophobic drug paclataxel. AI-850™ appears to be bioequivalent to Abraxis Bioscience’s Abraxane®, a leading cancer drug that some analysts expect will reach peak sales of $1 billion a year. Acusphere has licensed its HDDS technology for oncology therapeutics applications, as well as the rights to AI-850™, to Cephalon Inc.