Genzyme Corporation Ad2/CFTR-2 Gene Transfer Protocol: Single 
One Kendall Square, Cambridge, MA 02139 Aerosol Administration to the Lung of CF Patients 
Study Summary 
This study will evaluate the safety of the administration of Ad2/CFTR-2 to the pulmonary airway of patients with CF. A 
total of 16 patients with mild to moderate disease will be enrolled in the study. There will be 8 study groups of 2 patients 
each, with each patient within a group receiving the same dose of Ad2/CFTR-2. The study treatment doses range from 
8 x 10 6 to 2.5 x 10 10 IU and slowly increase from the lowest dose to the highest dose in half log increments. This 
protocol is an extension of a protocol for bronchoscopic administration of Ad2/CFTR-2 to a lobe of the lung of CF 
patients. We intend to conduct these protocols simultaneously. We will maximize safety in this protocol by evaluating 
lobar administrations of the lowest dose and the next higher dose of Ad2/CFTR-2 to a total of 6 patients prior to initiating 
the aerosol protocol. We have timed these two protocols such that prior to advancing to the next higher aerosol dose, 
an equal dose and the next higher dose will have been administered by bronchoscope to a lobe of the lung. We will 
have evaluated the equal dose for two months and the next higher dose for one month. No patient will receive an 
aerosolized dose of Ad2/CFTR-2 to the whole lung until the following, higher dose group has begun localized 
administration. This provides an additional measure of safety to the entire protocol by lengthening the observation 
period before aerosolization begins. (Please refer to the protocol flow sheet on page 17 for an illustration.) 
Each patient will be followed for 21 days prior to treatment, then they will be treated and closely monitored for 28 days 
post treatment. This post-treatment monitoring includes 3 days as an inpatient, with discharge on the fourth day, and 
then 24 days as an outpatient. Each patient will be assessed for evidence of an adverse systemic, immune, 
inflammatory or respiratory response to Ad2/CFTR-2. Patient specimens will also be examined throughout the study for 
any evidence of Ad2/CFTR-2 viral shedding. Subsequently, patients will be monitored on a monthly basis for 6 months 
and then at least every 3 months for 1 year. The patients will be followed for ten years by annual query. 
At post treatment day 7 of the study, each patient will undergo bronchoscopy during which a brushing will be performed 
using a lobe which was likely to have been exposed to the vector. Specimens from the brushing will be evaluated for 
biochemical efficacy. Specifically, analysis of gene expression by RNA template-specific PCR (RS-PCR) will be 
performed. BAL specimens from a control and treated lobe will be obtained in the concurrent lobar protocol. 
Background and Rationale 
In our previous RAC approved protocol using Ad2/CFTR-1 (ORDA #9212-036) we provided a discussion of CF and CF 
lung disease as background and provided references as documentation. We will not repeat that here. The major points 
are: a) Cystic fibrosis is a common genetic disease [1]. b) Although there are a variety of clinical manifestations, 
severe chronic lung disease is the major cause of morbidity and mortality, c) Although improvements have been made, 
no treatment is directed at the underlying defect. As a result CF remains a chronic, terminal and incurable illness with 
approximately 50% survival at age 30 years (CF Foundation Patient Registry). 
Considerations for Gene Therapy of CF 
Target Tissue for Gene Transfer : It is unlikely that any gene therapy protocol will correct 100% of the airway epithelial 
cells that normally express CFTR. Our data in cultured cell models and that of other investigators suggest that 
correction of a fraction of the cells may be sufficient to at least partially correct the chloride transport defect [8] . 
Although the safety of overexpressing CFTR is not known with certainty, current data suggest that there may be a 
reasonably wide therapeutic index. 
Adenovirus Vectors for Gene Transfer to Patients with CF : Adenoviruses are widespread in the human population. 
Viral infection, especially with the Ad2 and Ad5 serotypes of subgenus C, is generally not associated with serious 
disease [9, 10]. Infection usually results in mild respiratory tract symptoms. Exposure to the virus is widespread with 
the majority of adults being seropositive for serotype C adenoviruses. Engineered adenovirus offers an attractive 
means by which gene therapy for cystic fibrosis might be achieved [11-13] . The advantages and potential 
disadvantages of using an engineered adenovirus have been extensively reviewed in our previous RAC applications. 
Adenoviruses have an impressive safety profile in terms of the toxicity of wild-type infections, their use in vaccines, their 
lack of oncogenicity in humans, and our initial trials in humans. Adenovirus also has some potential disadvantages; the 
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Recombinant DNA Research, Volume 20 
