A recent study published in Molecular Therapy has provided compelling preclinical evidence supporting the use of ADVM-062 (now BGTF-027) as a gene therapy for blue cone monochromacy (BCM). BCM is characterized by the congenital absence of functional L- and M-opsins, resulting in poor visual acuity and severe color discrimination deficits.
Historically, experimental ocular gene therapies have relied on subretinal injections. However, this delivery method poses significant risks to the fragile central retinal structure, particularly the fovea, in BCM patients. To address this, researchers developed ADVM-062, an adeno-associated virus (AAV.7m8) vector optimized for intravitreal delivery and cone-specific expression of human L-opsin.
The preclinical evaluation involved testing the therapy in Mongolian gerbils, which naturally lack L-opsin, and non-human primates. In gerbils, a single intravitreal administration of ADVM-062 successfully transduced cone photoreceptors and produced a de novo response to long-wavelength stimuli.
Further studies in non-human primates confirmed that the therapy achieved meaningful foveal cone transduction at well-tolerated doses. Specifically, doses of 3 × 10^10 vector genomes per eye resulted in the transduction of 18% to 85% of foveal cones. These findings suggest that an intravitreal approach can safely and effectively target the necessary cells without the risks associated with subretinal surgery.
These promising preclinical results pave the way for future clinical trials, offering hope for a one-time, less invasive treatment option for individuals living with BCM.
Medical Disclaimer: This information is for educational purposes only and does not constitute medical advice. Genetic testing and clinical management should be performed by qualified healthcare professionals.