HuidaGene Therapeutics (HuidaGene) announced that the US. Food and Drug Administration (FDA) has cleared its investigational new drug (IND) application for the planned multi-national clinical trial of HG004 for the treatment of patients suffering from RPE65 mutation-associated inherited retinal dystrophies, a group of genetic diseases caused by the mutations in RPE65 gene affecting the retina and passed on to the children.
"We are thrilled to have received the IND clearance of our HG004 program from US FDA, marking our first IND clearance as a company and our first retinal disorder program to reach clinical development stage," said Xuan Yao, PhD, co-founder and CEO of HuidaGene. "Clearance of this IND is a testament to the in-house pipeline development capabilities and high-quality preclinical data supporting HG004, as well as the strong CMC and analytics capabilities through our partnership with WuXi Advanced Therapies. The goal of the HG004 program is to develop a one-time, non-AAV2 gene replacement therapy to restore, treat, and prevent blindness of children and adults with severe visual impairment or blindness due to RPE65 mutation-associated retinopathies globally."
Investigational HG004 is a novel ophthalmic injection that is being developed to treat RPE65 retinopathies. Based on the head-to-head preclinical comparison study of HG004 and adeno-associated virus serotype 2 (AAV2) at the same dose, the recovery of the retinal functions was increased by 67.6% (HG004) and 35.8% (AAV2 products) when compared to the wild-type mice in the Rpe65 knockout murine model at Week 17 after a single injection. Therefore, HG004 demonstrates better transduction efficiency of the retinal pigment epithelium (RPE) compared with AAV2 and has the potential to lower the total vector doses, which may reduce the risk of AAV vector-associated immunogenicity or ocular adverse events in humans.
"We are excited by the promise of HG004 to offer a potential transformative treatment better than AAV2-mediated gene replacement therapy," said Hui Yang, Ph.D., Co-Founder and Chief Scientific Advisor of HuidaGene. "Our extensive preclinical studies demonstrated superior transduction efficiency and substantial restoration of vision loss at the RPE layer when HG004 compared to AAV2 through our independently-developed Rpe65 gene knockout murine disease model, which is found to mimic the retinal phenotypes and functions of patients with RPE65 mutation-associated inherited retinal dystrophies."
"Our preclinical data supported our planned multi-national clinical trial with a starting effective dose far lower than the approved AAV2-hRPE65 gene therapy product and with less volume need to be injected into the retina," said Dr. Xuan Yao. "We had already enrolled patients at the end of 2022 in our investigator-initiated trial (IIT) in China, and we saw a substantial restoration of vision that were progressing toward complete blindness even with nearly 25-fold lower vector doses of HG004 than the approved AAV2-hRPE65 gene therapy product within seven days after the single-injection of HG004."
About multi-national clinical trial of HG004
HG004 will be evaluated in a multinational, multicenter, multiple-cohort, dose-finding study of adult and pediatric subjects with RPE65 retinopathies under one master protocol in different countries. The purposes of the study are to evaluate the safety, tolerability, efficacy, and long-term clinical durability of a single injection of HG004 for up to 52 weeks. Primary endpoints include adverse events, certain laboratory measures, and ophthalmic examinations. The study will also assess visual function via a multiluminance mobility test (MLMT), where subjects will navigate a mobility course under various light levels. After completing the primary study period, subjects will continue to be assessed in a long-term follow-up study of HG004.
About RPE65 mutation-associated inherited retinal dystrophies
Inherited retinal dystrophies (IRDs) are a group of rare blinding conditions caused by mutations in any 1 of more than 250 genes. Leber's congenital amaurosis (LCA), severe early childhood-onset retinal dystrophy (SECORD), early-onset severe retinal dystrophy (EOSRD), and retinitis pigmentosa (RP), which may all be grouped under the heading of RPE65 mutation-associated inherited retinal dystrophies, are considered to represent a phenotypic continuum of the same disease.
The RPE65 mutation-associated inherited retinal dystrophies with a typical onset between birth and five years of age exhibit several common clinical findings, chiefly night blindness (light staring with profound nyctalopia and nystagmus), progressive loss of visual fields, and loss of central vision. The percentage of patients (with biallelic RPE65 mutations) meeting the World Health Organization (WHO) criteria for blindness increased with age and reached 100% after the age of 40 years.
Given the often severe and early visual loss associated with RPE65 inherited retinal dystrophies, other areas of development, including speech, social skills, and behavior, may also be delayed.
About HuidaGene
HuidaGene Therapeutics is a global clinical-stage biotechnology company focusing on discovering, engineering, and developing CRISPR-based genetic medicine to rewrite the future of genomic medicine.
Based in Shanghai and New Jersey, HuidaGene is committed to addressing patients' needs globally with various preclinical therapeutic programs covering ophthalmology, otology, myology, and neurology. The company's CRISPR-based therapeutics offer the potential to cure patients with life-threatening conditions by repairing the cause of their disease. HuidaGene is committed to transforming the future of genome-editing medicine.