One-time Gene Therapy RGX-181 Wins FDA Rare Pediatric Disease Designation

The U.S. Food and Drug Administration has granted rare pediatric disease designation to Regenxbio’s one-time gene therapy RGX-181 for the treatment of late-infantile neuronal ceroid lipofuscinosis type 2 (CLN2) disease, one of the most common forms of Batten disease.

Regenxbio plans to submit an investigational new drug (IND) to the FDA in the second half of 2019 to test RGX-181 in a first human clinical trial.

RGX-181 was designed to deliver a healthy copy of the TPP1 gene — mutations in this gene are the underlying cause of late infantile Batten disease, or CLN2 — to cells of the central nervous system (brain and spinal cord) using a viral carrier called adeno-associated virus 9 (AAV9).

Regenxbio’s NAV Technology Platform contains several of these non-replicating viral delivery vehicles, meaning they are unable to cause disease. Moreover, these AAVs do not attract the attention of the immune system, avoiding an unwanted immune response.

The FDA’s decision is preceded by an orphan drug designation granted in November 2018, which provides a special status for a drug or biological product to treat a rare disease, defined as those affecting fewer than 200,000 people in the U.S.

“There is an urgent need for treatment options for CLN2 disease, a serious and life-threatening disease, which is emphasized by RGX-181 receiving Rare Pediatric Disease Designation, in addition to Orphan Drug Designation,” Kenneth T. Mills, president and CEO of Regenxbio, said in a press release.

If a new biologics license application for RGX-181 is approved, Regenxbio could become eligible to receive a priority review voucher from the FDA, which can then be used for any subsequent marketing application. This program is intended to encourage the development of therapies to prevent and treat rare pediatric diseases.

Preclinical data using animal models of CLN2 disease showed that a single injection of RGX-181 led to a wide expression of the TPP1 enzyme throughout the cells of the central nervous system. The therapy significantly improved animals’ neuro-behavior and extended their survival.

“We believe that RGX-181 administered as a one-time treatment can potentially correct the underlying genetic condition and halt the progression of this devastating disease. We look forward to filing an IND with the FDA for the first-in-human clinical trial in the second half of 2019,” Mills said.