Wilmott, RW; Whitsett, JA; Trapnell, B; Wert, S; Baughman, R; Cuppoletti, J; Tolstohev, P; ,
The purpose of this study is to evaluate the safety and efficacy of gene therapy of cystic fibrosis with a replication-deficient, Delta E1, Delta E3 deleted adenoviral vector that directs expression of the normal CFTR mRNa and CFTR protein in mammalian cells. The virus, Av1Cf2, will be administered to the upper (nasal) and lower (lobar bronchial) respiratory tract of patients with cystic fibrosis. This protocol is designed to demonstrate (1) the expression of normal CFTR mRNA in vivo, (2) the synthesis of CFTR protein, and (3) the correction of epithelial cell cAMP-dependent Cl- permeability associated with cystic fibrosis. Potential toxic effects of Av1Cf2 will be monitored by measuring clinical, radiographic, physiologic, and biochemical parameters. The pharmacokinetics or longevity of expression with Av1Cf2 will be determined. Systemic and local immunologic consequences of Av1Cf2 infection, the time of viral survival, and the potential for recombination or complementation of the virus to produce a replicating virus will be monitored in assessing the safety of the AV1Cf2 recombinant virus. The safety and potential risks of exposure of personnel and cohorts of the patients after Av1Cf2 administration will be assessed.Consenting male or female patients of age 18 or greater with forced expiratory volume in one second (FEV(1)) >40% and genetically proven cystic fibrosis will be recruited from the Cystic Fibrosis Center at Children's Hospital Medical Center, Cincinnati. Patients enrolled in the study will undergo an initial screening evaluation and will then be admitted to the Research Center, Children's Hospital. They will undergo a two-week period of intensive pulmonary toilet including antibiotics, postural drainage, aerosols, mucolytics, and/or DNAse therapy (pending FDA approval of DNAse). Pulmonary function tests will be evaluated pre- and post-''cleanout.'' Av1Cf2 will then be administered to specific regions of the nose with each patient group receiving 1 x 10(6), 3.3 x 10(6), 1.0 x 10(7), 3.3 x 10(7), or 1 x 10(8) pfu to defined areas of the nasal epithelium. CFTR mRNA, CFTR protein, and Cl- permeability will be assessed in nasal epithelial cells. Two days later, the patient will receive the Av1Cf2 in the airways of the right or left lower lobe during bronchoscopic examination. Patient groups will receive 1 x 10(6), 3.3 x 10(6), 1 x 10(7), 3.3 x 10(7), or 1 x 10(8) pfu per dose in the lung. Clinical, radiographic, physiologic, and cellular evidence of efficacy and toxicity will be assessed post administration. Viral clearance and replication will be assessed, and the patient discharged when clear of infectious Av1Cf2 virus.The virus, Av1Cf2, was constructed by Genetic Therapy, Inc., Gaithersburg, Maryland, from genetic material obtained from the adenovirus serotype 5. In Av1Cf2, human CFTR mRNA synthesis is driven by the RSV (Rous sarcoma promoter-enhancer) and terminates with SV40 poly A signals. The virus harbors deletions in the E1 (Delta E1) and E3 regions (Delta E3) to block replication and to provide insert space for the incoming cDNA, respectively. Similar adenoviral constructs have been used to transfer cDNAs for a variety of genes to various mammalian cells in vitro and to lung epithelial tissues in vivo by this laboratory and by others. It is hoped that these studies will demonstrate the biologic expression in vivo and the safety of the Av1Cf2 vector as a phase I study and support the long-term goal of CFTR gene transfer that will lead to physiologically, and ultimately clinically, relevant reconstitution of the abnormalities that cause pulmonary disease in cystic fibrosis.