Significant improvements in the treatment of cystic fibrosis (CF) have occurred over the past 30 years due to drug delivery via inhalation aerosols. However, the efficacy inhaled therapies is dramatically reduced in CF patients because of the presence of a viscous mucus transport barrier within the airways, extensive degradation and metabolism of inhaled drug prior to exerting its pharmacological action, and the development mucoid Pseudomonas aeruginosa colonies. Often drugs or gene vectors cannot reach the intended target before their activity has been reduced or eliminated. Poor transport efficiencies in drug delivery have lead to the failure of therapies including the inability to attain the relatively low efficiencies required for gene therapy success. Applying the unique transport and active properties of nanoscale systems in drug delivery is a promising strategy for overcoming the biological barriers in CF lung disease. In particular, the ability of nanoparticles systems to exert strong influences on their environment using heat (a nanoknife) and magnetic fields (nano-pullies) are attractive functional attributes for increasing transport and drug distribution in CF lung disease. The long term objectives are to overcome these barriers and achieve critical improvements in CF therapy. The CENTRAL HYPOTHESIS of the proposed research is that novel multifunctional nanoparticles will facilitate significant enhancement of the efficacy of model therapeutic agents due to increased diffusion and penetration through mucus and biofilm barriers in cystic fibrosis when administered as an aerosol. Our preliminary data have demonstrated that (1) marked increases in particle and bulk transport of nanoparticles can be attained during nano-pulley mode, (2) we prove that our nanoparticles can be heated and they act like nanoknives cutting through biopolymers such as DNA that causes CF mucus to be diffusion limiting, (3) we demonstrate also our ability to synthesize a number of different types of magnetic nanoparticles for use in these studies: core-shell composites for use in image studies and surface functionlized particles for drug conjugation (4) we then functionalized these particles, attaching a model drug to the surface using a bio- cleavable conjugation scheme, (5) Drug release could be triggered using magnetic fields, (6) and finally, we then loaded the nanoparticles into inhalable microparticles suitable for aerodynamic lung targeting. These exciting preliminary data strongly support the rationale and feasibility of the proposed approach. Moreover, the interdisciplinary team has a very strong record in each of the critical areas of the project: pulmonary drug delivery, nanoparticles design and engineering, and the molecular genetics and microbiology of CF. The main objective of the proposed research is to develop, synthesize, characterize, and evaluate novel particle systems that simultaneously allow controlled lung deposition and enhanced transport in CF disease. These systems will provide high drug concentrations delivered directly to the site of action and will therefore facilitate significant improvements in drug and gene therapies in CF, prolonging survival and enhancing quality of life. Therefore, the SPECIFIC AIMS of the exploratory R21 phase of the project are (i) Prepare and characterize multifunctional nanoparticles and incorporate them into micro-systems suitable for inhalation via a dry powder aerosolization, (ii) Characterize drug transport and delivery performance of particles for CF therapy in vitro, and (iii) Evaluate in vivo efficacy and safety of the multifunctional nanoparticle pulmonary delivery system versus aerosolized controls. The results of the R21 phase will demonstrate the initial feasibility of this approach. The R33 phase of the proposed work will be focused on optimization of the nanosystems and biocompatibility evaluation. This innovative application of nanotechnologies to CF lung disease will also have potential in other lung diseases where transport barriers to drug delivery exist: tuberculosis, lung cancer, COPD, etc. The proposed studies will fill important gaps in our understanding of the systems of pulmonary drug delivery of nanosystems and subsequently how controlled administration of drug and gene therapies may impact CF treatment strategies.

Public Health Relevance

Cystic Fibrosis (CF) is one of the most common fatal inherited diseases. There is no cure for CF, and most individuals with cystic fibrosis die young - in their 20s and 30s from lung failure. Ultimately, lung transplantation is often necessary as CF worsens. Lung disease results from clogging of airways due to inflammation. Inflammation and infection cause injury to the lungs and structural changes that lead to a variety of symptoms. One of the major reasons for the poor life expectancy is the inability of therapies to overcome barriers within the airways (obstruction, poor penetration through mucus, extensive degradation of therapeutic). Thus new therapeutic options are urgently required that are more efficacious and have improved targeting. We are using CF as a model disease to develop the nanotechnologies described in this application given that this disease: (1) is well studied, (2) has a number of transport barriers to be overcome, (3) relevant in vitro and in vivo models are available. However, the findings of these studies will be directly relevant and applicable to many lung diseases such as TB, COPD, asthma, and chronic lung infections. Moreover, the ability to enhance drug transport through biofilms is widely applicable to many infectious diseases.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Exploratory/Developmental Grants Phase II (R33)
Project #
5R33HL092812-03
Application #
8286084
Study Section
Special Emphasis Panel (ZRG1-CB-N (50))
Program Officer
Buxton, Denis B
Project Start
2010-07-01
Project End
2014-06-30
Budget Start
2012-07-01
Budget End
2013-06-30
Support Year
3
Fiscal Year
2012
Total Cost
$711,169
Indirect Cost
$97,942
Name
University of Texas Austin
Department
Pharmacology
Type
Schools of Pharmacy
DUNS #
170230239
City
Austin
State
TX
Country
United States
Zip Code
78712