The Solution - The AVT Gene Transfer Technology
The AVT core technology consists of a state-of-the-art gene transfer vector with outstanding efficacy and safety features. A vector is a vehicle that transfers therapeutic genes into target cells. The AVT vector efficiently transfers genes into animal and human cells. The vector is particularly effective in transferring genes into the retinal cells of the eye.
The AVT vector is derived from an animal lentivirus that does not cause human disease. All of the viral genes have been removed. Importantly, the AVT gene transfer system incorporates extensive safety features that equal or exceed those of all other similar vector systems.
The Therapeutic Strategy Via Gene Therapy
The AVT strategy is one in which a single administration of the gene transfer vector to the eye will provide sustained delivery of a therapeutic protein to the retina. The AVT vector, encoding the therapeutic gene, will be injected into a peripheral region of the retina. Cells at the injection site will internalize the therapeutic gene and begin to secrete the therapeutic protein. The genetically-modified cells will remain highly localized at the injection site while the therapeutic protein they secrete will diffuse throughout the back of the eye and constantly bathe the entire retina (Figure 2). The genetically-modified cells will continue to secrete the therapeutic protein for years, thereby providing sustained therapy with a single treatment.
Figure 2. The AVT gene transfer technology. The AVT product will be administered to a peripheral portion of the retina. Cells at the injection site (blue circle) will continuously secrete the therapeutic protein (green arrow), which will spread throughout the retina.
AVT is pioneering products with two types of therapeutic genes. The first product will produce proteins that eliminate the new blood vessels that cause wet age-related macular degeneration (Figure 3). AVT has obtained proof of concept with this strategy. The lead therapeutic protein for AVT's first product (AVT-1) is Kininostatin. Kininostatin is a potent anti-angiogenic protein that will block the growth of defective new blood vessels irrespective of the angiogenic stimulus. AVT-1 will prevent the development of new blood vessels, block the conversion from dry to wet age-related macular degeneration and therefore, prevent the rapid deterioration of vision typical of wet age-related macular degeneration.
Figure 3. AVT's first product, AVT-1, will deliver a therapeutic protein that will inhibit new blood vessel growth and will block the conversion from dry to wet age-related macular degeneration. Compare to Figure 1.
AVT's second product (AVT-2) will produce proteins that are designed to nurture the retina and prolong the life of the photoreceptors (Figure 4). The lead therapeutic for AVT-2 is Rod-derived Cone Viability Factor (RdCVF), which will function to protect the photoreceptors in the retina and slow down the degeneration process typical of dry age-related macular degeneration and retinitis pigmentosa.
Figure 4. AVT's second product, AVT-2, will protect the photoreceptors (PR) in the retina and slow down the degeneration process typical of dry age-related macular degeneration.