M.J. Welsh and A.E. Smith, RAC Application 
Ad2-ORF6/PGK-CFTR 
Item 5 - Clinical Protocol 
ADENOVIRUS-MEDIATED GENE TRANSFER FOR CYSTIC FIBROSIS: 
Part A. Safety of Dose and Repeat Administration in the Nasal Epithelium 
Part B. Clinical Efficacy in the Maxillary Sinus 
Investigator : 
Coinvestigators : 
Michael J. Welsh, M.D. 
Joseph Zabner, M.D. and Scott M. Graham, M.D. 
INTRODUCTION 
Cystic fibrosis (CF) is a common lethal autosomal recessive disease of Caucasians (1-3) caused by 
mutadons in the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR) (4-6). 
CFTR is a chloride channel which is regulated by phosphorylation and by intracellular nucleoddes (7). 
Mutadons in the CFTR gene cause a loss of funcdon of the CFTR chloride channel and thus contribute to 
the hallmark of the disease: defective electrolyte transport by affected epithelia (1,8). Although there are a 
variety of clinical manifestations, lung disease is the major cause of morbidity, and despite current 
standard therapy the median survival rate is only 26 years. Recently obtained knowledge of the gene that 
encodes CFTR, an understanding of the function and biochemistry of the protein product, and insight into 
the molecular basis of the disease (3,7,9,10), suggest that gene transfer could represent an important 
advance in treatment. 
The feasibility of gene transfer to lung cells was initially demonstrated by our finding that expression of 
the cDNA for wild-type CFTR corrected the chloride channel defect in cultured CF airway epithelia (11). 
In collaboration with Dr. Alan E. Smith and his colleagues at Genzyme Corp., we constructed and tested 
recombinant adenovirus vectors to deliver CFTR cDNA to airway epithelial cells in cell culture models 
and in animals; papers describing the results of those studies are included as Appendices 7.5, 7.6, and 
7.7. 
Based upon the results of those studies and additional work, we received approval from the University of 
Iowa IRB and IBC, the NIH RAC, and the FDA for a single dose nasal application of an adenovirus- 
based vector encoding CFTR to three patients with CF. We have now completed that study and a 
manuscript describing the results is included as Appendix 7.8. We found that administration of an 
adenovirus vector corrected the chloride transport defect that is the hallmark of CF-affected epithelia. We 
have also received IRB and IBC approval for the study of three additional patients under an addendum to 
that protocol; approval of the NIH RAC and the FDA is pending. 
We are now requesting approval for a study that is designed to address two of the most pressing issues 
regarding the use of adenovirus vectors for the treatment of CF airway disease. 
In Part A, we address the safety of dose and repeat administration to the nasal epithelium. There are 
two main issues: a) Is repetitive administration safe? Because adenovirus rarely integrates, gene therapy 
for CF will require repeated vector administration, b) Is administration of increased doses safe? In our 
initial study (Appendix 7.8), we used low doses of vector, but transfer of CFTR cDNA to the 
intrapulmonary epithelium will require higher doses. 
In Part B, we ask whether delivery of the an adenoviral vector encoding CFTR is of clinical efficacy. 
We will deliver AD2-ORF6/PGK-CFTR to the sinus mucosa of five to ten CF patients to learn if Ad2- 
ORF6/PGK-CFTR can treat CF clinical disease in the maxillary sinus. We have chosen the maxillary 
sinuses because the morphology, function, and clinical abnormalities are similar to those found in the 
intrapulmonary airways. The study will also allow us to determine if repeat administration of an 
adenovirus vector is safe. The proposal is designed to answer these questions in a way that minimizes 
risk to the patients, yet provides guidance for the future direction of gene therapy to treat CF. 
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