Novel Technique for IV Injection of Hydrophobic Drugs
Overview
Intravenous delivery is the quickest, most reliable means of distributing drugs throughout the body. Injected materials, however, are normally cleared over the course of mere hours via organs such as the liver, spleen, and kidney and, more generally, by the mononuclear phagocytic system. Our novel technique for IV injection of hydrophobic drugs is based on the idea that hydrogel microparticles can be injected safely, and will persist longest in circulation, when their size and stiffness closely align with those of white blood cells.
Market Opportunity
The use of micro/nanoparticles for drug delivery has become common, as it protects the encapsulated molecules and allows for controlled release. Like other foreign materials, however, these particles are rapidly cleared from the blood. While normally a good thing, rapid clearance from the blood is a problem when longer persistence times are needed for medicinal reasons. Though nanoparticles have garnered much attention, they generally have short circulation times and, because of their small volumes, are not ideal for achieving days-long release. Larger microparticles can encapsulate more drug for longer release times but face the additional challenge of vascular persistence, as they become lodged in capillaries.
Innovation and Meaningful Advantages
Our novel technique for IV injection of hydrophobic drugs is based on the idea that hydrogel microparticles can be injected safely, and will persist longest in circulation, when their size and stiffness closely align with those of white blood cells (~10 μm, <0.5 kPa). We are identifying the optimal characteristics for hyper-compliant microparticles (HCMPs) that are large enough to encapsulate substantial amounts of drug yet deformable enough to pass through even the smallest constrictions in the circulatory system and evade uptake by phagocytic cells. Such particles are expected to extend vascular persistence from hours to days.
Many current methods of preparing hydrophobic drugs (and other agents) require multiple processing steps. In medicine, these can cause loss of bioactivity, particles that are too large or of inconsistent size, low yields, and problems with drug delivery. We have developed a method of encapsulating hydrophobic agents that uses a set of solvents and solutions to micronize the agent, giving it enhanced properties and greater bioavailability. This method allows the formation of particles with an average size of less than 1 micron. Advantages of micronized drugs in encapsulated delivery include enhanced bioactivity and bioavailability. In addition, the final product can contain less than 5% polymer carrier, if any, and be surfactant-free.
Collaboration Opportunity
We are interested in exploring 1) research collaborations with leading pharmaceutical companies to develop this method of drug delivery; 2) startup opportunities with investors in the drug delivery space; and 3) licensing opportunities for drug delivery.
Principal Investigator
Eric Darling, PhD
Associate Professor of Medical Science, Engineering and Orthopaedics
Brown University
eric_darling@brown.edu
https://vivo.brown.edu/display/ed12
Edith Mathiowitz, PhD
Professor of Medical Science
Professor of Engineering
Brown University
edith_mathiowitz@brown.edu
https://vivo.brown.edu/display/emathiow
IP Information
2004-06-08;US6746635B2; Issued.
2013-09-03;US8524829B2; Issued.
Brown Tech ID #1429
Publications
Azagury A, Fonseca VC, Cho DY, Perez-Rogers J, Baker CM, Steranka E, Goldenshtein V, Calvao D, Darling EM, Mathiowitz E. Single Step Double-walled Nanoencapsulation (SSDN). Journal of Controlled Release. 2018 June 08;280;11-19. doi.org/10.1016/j.jconrel.2018.04.048.
Labriola N, Mathiowitz E, Darling E. Fabricating polyacrylamide microbeads by inverse emulsification to mimic the size and elasticity of living cells. Biomaterials Science. 2017;5;41-45. doi: 10.1039/C6BM00692B.