The RAC on Friday unanimously approved two protocols for delivering genes directly intopatients.
One of the two in vivo DNA transfers is aimed at cancer immunotherapy; the otherat correcting a hereditary disease, cystic fibrosis. Before the Phase I clinicals canbegin, the FDA must add its own green light to RAC's authorizations.
The cancer trial, sponsored by Vical Inc. of San Diego will take place at the MayoClinic's Comprehensive Cancer Center. Vical Inc. will supply the antigen-encoding DNA,wrapped in its proprietary “cytofectin“ phospholipid vector, to oncologist JohnKovach, who directs Mayo's cancer center. The trial will enroll 15 patients whosecolorectal tumors have spread to their liver. The study will test both single-dose andmultidose escalations to evaluate safety and immune stimulation.
Vical's vice president and chief financial officer, Martha Demski, told BioWorldthat the company's sponsorship of the impending studies involves designing the protocoland paying for the clinical work and the physician's time.
The cystic fibrosis study at the University of Alabama, under clinician Eric Sorscher,will administer the gene for transmembrane conductance factor, missing in cystic fibrosispatients, via intranasal inhalation. Sorscher's study is sponsored by Genzyme Corp. ofCambridge, Mass which has an option to use Vical's cytofectins, and will supply its owngene construct to Sorscher, Demski said.
This marks the second time that RAC has permitted human trials of gene therapy bydirect injection of DNA into a patient, rather than via a conventional indirect vector,such as a retroviral vehicle. Its first authorization, in February 1992, allowedUniversity of Michigan molecular biologist Gary Nabel to inject the tumors of end-stagemelanoma patients with antigenic proteins.
Nabel reported success with this approach in the Dec.1 issue of the Proceedings ofthe National Academy of Sciences. The University of Michigan licensed Vical to employNabel's pioneering methods in developing its own in vivo technology, and Nabel sitson the company's scientific advisory board.
-- David N. Leff