A Drug Delivery Platform for Targeting Intracellular Pathogens
For Information, Contact:
Dario Valenzuela
Senior Commercialization Manager, Life Sciences
Web Published:
Iowa State University researchers have developed an improved method for delivering antibiotics inside infected cells for more effective treatment.

Development Stage:
Co-localization of the polyanhydride particles with the intracellular pathogen M. paratuberculosis in tissue culture cells has been demonstrated, and ISU is seeking partners interested in commercializing this technology.

Bioerodible polymers have been researched for potential biomedical applications like drug or vaccine delivery for a number of years.  For example, polyesters such as poly(lactic-co-glycolic acid) (PLGA) have been FDA approved for some applications; however, their suitability for others, such as vaccine delivery, is limited by factors that affect the stability of protein immunogens, such as producing a low pH milieu or inducing protein aggregation as well as acidic compartmentalization that is detrimental to the effectiveness of most antibiotics. In contrast, polyanhydrides have a number of potential advantages for biomedical applications, including chemistry-dependent surface erosion and payload release, a moderate pH microenvironment, and better protein stabilization; polyanhydrides have been used for delivery of plasmid DNA, small molecular weight compounds, and vaccine components.  In addition, polyanhdride microspheres and nanospheres (PAparticles) elicit unique cellular responses from immune cells that stimulate internalization, direct intracellular trafficking and degrade slowly within the cells.  Varying the chemistry of the particle affects particle degradation and alters the fate of the particle within cells. This characteristic can be exploited to target intracellular pathogens which evade host defenses by adapting themselves to the environment within cells and escape killing by antibiotics.  ISU researchers have now developed PAparticles with modified surface chemistries that are capable of entering host cells and delivering antibiotics in the same microenvironment as that of an intracellular pathogen.  Loading of the antibiotics onto the PAparticles does not chemically modify the antibiotics or negate their antimicrobial function. This highly effective targeting of the intracellular environment has to potential to reduce the amount of antibiotic needed to treat such an infection and also provide delayed release, thus improving the bioavailablity of the drug.

• Enhanced uptake compared to PLGA particles
• Targets more favorable intracellular compartments
• Potential for longer bioavailability of encapsulated antibiotics
• Provides greater encapsulation of hydrophobic antibiotics compared to PLGA particles
Drug delivery

Patent Information:
*To see the full version of the patent(s), follow the link below, then click on "Images" button.
Country Serial No. Patent No. Issued Date
United States 12/940,872 8,449,916* 5/28/2013
United States 13/866,520 8,927,024* 1/6/2015

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