The FDA has granted the MeiraGTx Rare Pediatric Disease Designation (RPDD) for its AAV8-RK-RetGC program for the treatment of patients with Leber congenital amaurosis due to GUCY2D mutations (LCA1). Mutations in the GUCY2D gene coding for guanylate cyclase lead to severe retinal diseases in humans, with 88% of cases causing autosomal recessive Leber congenital amaurosis type 1 (LCA1) while heterozygous missense mutations cause autosomal dominant cone-rod dystrophy (CRD), the company explained in a press release.

In LCA1, photoreceptor function loss and blindness emerge very early in life. In CRD, degeneration starts in the cones and leads to loss of the central visual field due to the high presence of cones in the macula. CRD can lead to complete blindness when degeneration of rods follows those of cones.

MeiraGTx noted that this is the fourth RPDD it has received in the last 3 months, including AAV8-RK-AIPL1 for the treatment of LCA4 retinal dystrophy, AAV8-RK-BBS10 for the treatment of Bardet-Biedl syndrome due to BBS10 mutations and AAV5-RDH12 for the treatment of RDH12 associated retinal dystrophy.

“Receiving Rare Pediatric Disease Designation for an additional program in our ophthalmology pipeline represents another regulatory milestone for the company and demonstrates the groundbreaking therapeutic potential of our technology to address these severe childhood blinding conditions,” said Alexandria Forbes, PhD, MeiraGTx’s president and chief executive officer, in the press release. 

RPDDs may be granted by the FDA to drugs and biologics intended to treat certain orphan diseases affecting fewer than 200,000 patients in the United States, the serious or life-threatening manifestations of which primarily affect individuals aged 18 years or younger, MeiraGTx explained in its press release. Under the FDA’s Rare Pediatric Disease Priority Review Voucher program, a sponsor that receives approval for a biologics license application for a rare pediatric disease may be eligible to receive a voucher for a priority review of a subsequent marketing application for a different product.