Sanofi’s Neovascular Age-Related Macular Degeneration Gene Therapy SAR402663 Garners FDA Fast Track Designation

Sanofi’s SAR402663, an investigational gene therapy, has received fast track designation from the FDA for the treatment of neovascular age-related macular degeneration, also known as wet AMD.¹

SAR402663 comprises a one-time intravitreal treatment and is intended to inhibit vascular endothelial growth factor (VEGF) by providing a gene for soluble FLT01. Inhibition of abnormal blood vessel growth, a decrease in vascular leakage, and minimization of retina damage, and a lowering of treatment burden are among the intended effects of SAR402663.

The gene therapy is currently being assessed in a phase 1/2 clinical trial (NCT06660667). The study, which consists of dose escalation and dose expansion portions, is expected to enroll 66 patients in total. According to the clinicaltrials.gov page, which was most recently updated on July 4, 2025, it is currently recruiting patients aged 50 to 90 years at a number of sites in the United States. The estimated primary completion date for the trial is May 18, 2027.

SAR402663 is among several gene therapy products for AMD currently being developed by various companies. Notably, earlier this year Ocugen’s OCU410, which is under evaluation for the treatment of vision loss due to geographic atrophy associated with dry AMD, received a positive opinion from the European Medicines Agency and its Committee for Advanced Therapies.²

In addition, REGENXBIO is developing ABBV-RGX-314, an investigational adeno-associated virus (NAV AAV8) vector-based gene therapy intended to treat wet AMD.³ In October 2024, the company announced results from a phase 2 substudy (NCT03999801) that demonstrate the therapy’s ability to reduce the need for standard of care antiVEGF injections in patients with bilateral wet AMD who received treatment with the gene therapy in their fellow eye after previous treatment in an initial eye.

"The majority of our patients with wet AMD eventually have bilateral disease and face a substantial treatment burden with frequent lifelong injections in both eyes,” Arshad Khanani, MD, the director of clinical research and director of Fellowship at Sierra Eye Associates, said in an October 2024 statement.¹ “This leads to suboptimal real-world vision outcomes with current standard of care. The fellow eye dosing data with ABBV-RGX-314 is a milestone for the field of gene therapy for common retinal diseases, as this is the first time we have performed bilateral treatment for wet AMD patients. These results, combined with the durable treatment effect up to 4 years shown in long-term follow up, highlight the potential of ABBV-RGX-314 as a one-time effective treatment option for patients with wet AMD."

Another advanced therapeutic currently under development for wet AMD is HuidaGene Therapeutics’ HG202, an investigational CRISPR/Cas13 RNA-editing therapy.⁴ The therapy was cleared by the FDA for a phase 1 clinical trial in November of last year.

“This open investigational new drug application for HG202 by the United States FDA – the first regulator to have cleared CRISPR/Cas13 for clinical development – represents an important milestone for HuidaGene and the entire CRISPR gene-editing field of RNA editing,” Alvin Luk, PhD, MBA, CCRA, the cofounder and chief executive officer of HuidaGene, said in a November 2024 statement.¹ “We chose to go to the FDA because HG202 demonstrated good results in the invitro, in vivo preclinical studies and first-in-human ‘SIGHT-I’ trial. In September 2023, we dosed the world’s first novel CRISPR/Cas13 RNA-editing therapy in humans, and we recently presented preliminary data at the ARVO, ASGCT, EURETINA, and ESGCT this year. The rigor of our clinical data in China using a nonreceptor binding pathway approach through Cas13 RNA editor to partially knock down the mRNA expression of VEGFA brings the potential to AMD patients.”

REFERENCES
1. Sanofi’s SAR402663 earns fast track designation in the US for neovascular age-related macular degeneration. News release. Sanofi. September 11, 2025. Accessed September 17, 2025. https://www.sanofi.com/en/media-room/press-releases/2025/2025-09-11-05-00-00-3148313
2. Ocugen Announces Positive Opinion of EMA’s Committee for Advanced Therapies for ATMP Classification for Novel Modifier Gene Therapy Candidate OCU410 for Geographic Atrophy and OCU410ST for Stargardt Disease. Ocugen. Press release. Published March 3, 2025. Accessed September 17, 2025. https://www.globenewswire.com/fr/news-release/2025/03/03/3035695/0/en/Ocugen-Announces-Positive-Opinion-of-EMA-s-Committee-for-Advanced-Therapies-for-ATMP-Classification-for-Novel-Modifier-Gene-Therapy-Candidate-OCU410-for-Geographic-Atrophy-and-OCU4.html
3. REGENXBIO presents positive data from the phase II study of subretinal ABBV-RGX-314 in patients with bilateral wet AMD at AAO 2024. News release. REGENXBIO Inc. October 21, 2024. Accessed September 17, 2025. https://ir.regenxbio.com/news-releases/news-release-details/regenxbio-presents-positive-data-phase-ii-study-subretinal-abbv
4. HuidaGene therapeutics receives the first-ever FDA clearance of CRISPR/Cas13 RNA-editing HG202 for macular degeneration. News release.HuidaGene Therapeutics. November 4, 2024. Accessed September 17, 2025. https://www.huidagene.com/new/news/70