The purpose of this study is to determine if there are side effects from administering this 
virus (AAV-CFTR) carrying a normal copy of the CFTR gene to the nose and lungs of 
adult patients with CF. Although this genetically engineered virus is designed to 
supplement the gene that is defective in lung cells of CF patients, t his is not expected to be 
a one-time cure for CF. and no medical benefit is expected for the subjects in this initial 
trial . 
WHAT IS KNOWN ABOUT THE AAV VIRUS? 
The virus that is being used as a carrier for the normal CFTR gene is called adeno- 
associated virus or AAV. This is a naturally occurring human virus which is fairly 
common, with about 2/3 of adults having been exposed at some time in their lives. It 
probably enters the body through the nose and mouth, but unlike most other viruses, AAV 
does not cause an illness. In fact, it usually requires another "helper" virus to multiply 
itself. When AAV infects cells by itself it tends to go "latent", by silently inserting its DNA 
into the DNA of the host cell. It may remain dormant there for years, but can later re- 
emerge if the host cell is infected with a helper virus. In the latent stage, AAV does not 
appear to harm the host cell at all. When it is present with the helper virus, it does not alter 
the helper virus infection in any way. 
Because of AAV's unique properties, being a harmless virus that is designed to insert its 
DNA into host cells, scientists have been working to devise a way to use AAV to insert 
other genes into cells. In the current study, AAV-DNA has been altered so that it will carry 
along a normal, functioning version of the CFTR gene into cells of the nose and lung. 
AAV viruses altered in this way have been tested extensively in cells in culture, and in 
experimental animals. In those settings, the altered AAV carrying the CFTR gene will, in 
fact, insert the CFTR DNA into the target cells. If this can be successfully done with cells 
in the nose and lung of CF patients, we would hope that we could correct the functioning 
of those cells, and possibly treat or prevent illness due to the disease. 
Since this AAV virus has been altered, however, it is not entirely clear whether it will still 
be as harmless as the naturally-occurring virus. It is possible that the removal of some of 
AAV's own DNA could affect the safety of the procedure or alter the way the AAV DNA 
interacts with the host cell DNA. It is also possible that patients possess antibodies of AAV 
from previous exposures which could decrease the effectiveness of the altered AAV virus 
or lead to adverse reactions. 
WHICH PATIENTS CAN PARTICIPATE IN THE STUDY? 
Adult persons over the age of 18 with diagnosed cystic fibrosis and certain abnormalities in 
their CFTR gene will be considered for this study. Patients will be eligible if they meet 
ALL the following criteria. Patients must: 
1) have relatively mild lung disease; 
2) be able to understand what is required to take part in the study, and be able to 
understand the risks and potential benefits of being part of the study; 
3) be willing to use effective contraception for the one year duration of the study; 
4) NOT be pregnant or breast feeding; 
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