FDA Grants Orphan Drug Status to AAVB-081 for Usher Syndrome Type 1B Retinitis Pigmentosa

AAVantgarde Bio, an innovative clinical-stage biotechnology company based in Italy, recently achieved a significant milestone. On Dec. 02, 2024, the U.S. Food and Drug Administration (FDA) granted Orphan Drug Designation to AAVantgarde's leading program, AAVB-081, aimed at treating Usher Syndrome Type 1B (USH1B) retinitis pigmentosa.

Dr. Natalia Misciattelli, the Chief Executive Officer of AAVantgarde, highlighted the urgent need for therapies addressing the progressive vision loss associated with USH1B, which often leads to blindness. She emphasized that the FDA's designation underscores the critical necessity for such treatments and marks a vital step forward in developing their specific program.

The FDA's Orphan Drug Designation is a program that provides special status to drugs and biologics intended for rare diseases meeting particular criteria. This designation comes with several incentives such as tax credits for qualified clinical trials, exemption from certain user fees, and potentially up to seven years of market exclusivity following approval.

AAVB-081 is a groundbreaking intra-retinal product based on the AAV8 vector. This dual hybrid product targets Usher syndrome (USH1B) related to MYO7A genes. The technology behind AAVantgarde's dual hybrid platform involves two AAV8 vectors, each carrying half of an expression cassette for the Myo7A gene. Within the cell nucleus, these halves recombine into a complete transgene, producing therapeutically significant protein levels. This innovative approach has shown promising results in animal models.

Usher syndrome type 1B (Usher1B) is a genetic disorder affecting both the retina and the inner ear, resulting from mutations in the MYO7A gene. The therapeutic gene for Usher1B is notably large, measuring 6.7 kb, and cannot fit inside a standard AAV vector. In the U.S. and Europe, approximately 20,000 individuals suffer from Usher1B. Children with this condition are born deaf, experience balance issues, and begin losing their vision progressively from an early age. While surgical interventions exist to address hearing loss, no current treatments can halt the progression of vision loss leading to blindness.

AAVantgarde Bio stands out in the biotech industry with its development of two proprietary Adeno-Associated Viral (AAV) vector platforms designed to overcome the gene therapy cargo capacity limitations inherent in standard AAV vectors. These platforms can deliver large genes to various tissues, both ocular and non-ocular. Initially, AAVantgarde is focusing on inherited retinal diseases with significant unmet needs, with Usher syndrome type 1B being their leading clinical program.