Clinical-stage biotechnology company HuidaGene Therapeutics announced that the FDA has granted orphan drug designation (ODD) to HG004, its lead gene replacement therapy, for the treatment of inherited retinal dystrophies (IRD) linked to RPE65 mutations.
Refresh me on what orphan drug designation is.
Orphan drug designation (ODD) is given to certain orphan drugs that show promise for treating, preventing, or diagnosing orphan diseases (rare serious or life-threatening diseases or conditions that affect >200,000 patients in the United States).
Drugs in this category go through the same scientific review process as any other drug seeking approval for licensing. Through ODD, a drug qualifies for:
- Tax credits for qualified clinical trials
- Exemption from user fees
- Potential 7 years of market exclusivity following approval
Now HG004.
HG004 is a novel ophthalmic injection designed to treat RPE65 retinopathies such as Leber Congenital Amaurosis 2 (LCA2), severe early childhood-onset retinal dystrophy (SECORD), early-onset severe retinal dystrophy (EOSRD), and retinitis pigmentosa (RP). The FDA cleared the therapy in January 2023 for an investigational new drug (IND) application to support the launch of a multinational trial assessing HG004 for IRDs.
Any supporting clinical data already available?
A head-to-head, preclinical study compared equal dosages of HG004 and adeno-associated virus serotype 2 (AAV2). Retinal function recovery was found to increase by 67.6% for HG004 and 35.8% for AAV2 products when assessed using an RPE65 gene knockout murine disease model.
Click here to find out more on how its performance compares to AAV2.
So what will this new trial include?
The multinational, multi-center, multiple-cohort, dose-finding study will evaluate adult and pediatric patients with RPE65 retinopathies using one master protocol.
Safety, tolerability, efficacy, and long-term clinical durability of one HG004 injection is being assessed for up to 52 weeks, with primary endpoints including adverse events, ophthalmic examinations, and certain laboratory measures.
When is it launching?
HuidaGene plans on launching the trial within the next few months in multiple countries.