WASHINGTON _ Ashanti de Silva, age nine, is petite proof of the promise of genetherapy. By the age of two, Ashanti, had been ill for most of her young life.She could not eat. She lost weight. She endured an unending succession ofcolds and bouts of flu, her father told a congressional committee Wednesday.

Her illness was severe combined immune deficiency, an incurable conditionstemming from the absence of an enzyme, adenosine deaminase, a building blockof the immune system. Incurable, that is, before doctors at the NationalInstitutes of Health injected her with "gene-corrected" cells. Now, said fatherRaj de Silva, his daughter can lead a normal life.

Gene therapy, the manifestation of human's desire to heal from within, isslowly coming of age _ and promises to provide treatments for a wide range ofdiseases, as several witnesses told the House Committee on Science, Space andTechnology Wednesday.

But few patients have fared as well as Ashanti, the witnesses said.Gene-replacement technology remains in its infancy, and several dauntingtechnical problems must be resolved before gene therapy will take its place asa viable treatment for disease.

"Gene therapy is in its early stages, and it is not likely that commercialproducts will be available for several years," said Nelson Wivel, director ofthe Office of Recombinant DNA Activities at the National Institutes of Healthin Bethesda, Md.

But that is not for a lack of effort, he said.

So far, researchers have embarked upon nearly 100 experiments into potentialgene therapies, the majority for diseases other than the genetic deficiencydiseases that the technique was developed to treat. Sixty-three of theproposals focused on cancer, 10 on cystic fibrosis, six for AIDS and theremainder for a range of illnesses from familial hypercholesterolemia torheumatoid arthritis, Wivel said. Researchers still must develop injectablevectors that can be precisely targeted to carry therapeutic genes to siteswhere they will do the most good; methods for site-specific integration ofgenes; and techniques for regulating gene expression.

Much of the research into these conundrums is being conducted by small biotechfirms whose efforts are threatened by their inability to find secure fundingfor their work, said Jeffrey Swarz, a biotech analyst for CS First Boston.

Health care reform _ and the threat of cutbacks in drug reimbursements _ hashit them hard, Swarz said.

"Although there are over a dozen publicly traded gene therapy companies, mosthave found it very difficult to raise capital in the uncertain climate ofhealth-care reform," he said. "Likewise, because of the early stage of genetherapy, and the long lead time needed to develop and receive FDA approval fora drug, gene therapy companies are viewed as risky investments."

Robert Abbott, president of Viagene Inc., of San Diego, speaking on behalf ofthe Biotechnology Industry Organization, urged the committee to place thefinancing of biotech research high on its legislative agenda.

"In my view," he said, "the current climate in this country, particularly withregard to financing, is incompatible with continued technical leadership ingene therapy. I urge you to provide legislative leadership before we losecontrol over this important field." n

-- Steve Sternberg Special To BioWorld Today

(c) 1997 American Health Consultants. All rights reserved.

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