Gene Therapy Explained

In gene therapy for achromatopsia, an AAV vector containing a normal CGB3 or CGA3 gene is designed to provide instructions for normal protein production, thereby restoring cone photoreceptor function. By introducing a functional gene copy, gene therapy corrects the genetic defect causing the disease. The functional gene delivered by the AAV vector is expected to remain stable for many years, suggesting potential for long-lasting clinical benefits from a single administration.

AGTC possesses a strong intellectual property portfolio and expertise in the design, formulation, manufacture, and physical delivery of gene therapy products. For more information, visit www.agtc.com.

AGTC utilizes gene therapy to develop long-lasting treatments for severe diseases, primarily focusing on ophthalmology. Genetic defects in over 200 genes are linked to poor vision. Genes guide protein production; mutations lead to abnormal or absent proteins, causing disease. Gene therapy delivers a functional gene copy into a patient's cells to produce correct proteins, potentially reversing the disease.

Gene therapy employs engineered viruses called viral vectors to deliver genes into cells. Adeno-associated virus (AAV) vectors are ideal for retinal diseases due to their small size, weak immune response, and lack of disease causation in humans. In gene therapy, native AAV genes are replaced with a functional gene and a promoter, flanked by inverted terminal repeats for packaging.

AAV vectors are delivered to retinal cells via ophthalmic methods such as intravitreal or subretinal injection. Once administered, they enter the patient's cells and deliver the functional gene to the nucleus. This functional gene enables the production of normal proteins, correcting the underlying cause of the disease and potentially providing long-term therapeutic benefits for vision loss or blindness.

AGTC is developing gene therapies for rare inherited retinal diseases like achromatopsia, which currently lack treatment. Achromatopsia, present from birth, causes significantly reduced visual acuity, extreme light sensitivity (day blindness), and complete loss of color vision. This condition results from cone photoreceptors in the retina being unable to convert light into electrical signals, often due to mutations in the CGB3 and CGA3 genes.