PYC Therapeutics to develop a new generation of RNA therapeutics to change the lives of patients with inherited diseases. announced that studies in patient-derived cells show that its second drug candidate for Autosomal Dominant Optic Atrophy (ADOA) has rescued the critical functional deficit that causes blindness in patients with this disease5 for background information on ADOA and the functional deficits associated with this disease). ADOA is an orphan disease characterised by loss of vision in both eyes beginning in early childhood and often progressing to legal blindness in adulthood. The majority of ADOA cases are caused by mutations in a gene called Optic Atrophy 1 (OPA1), leading to a deficit of OPA1 protein. The OPA1 protein is crucial for healthy functioning of the cell's powerhouses called mitochondria. The mitochondrial dysfunction in ADOA patients can cause death of the retinal cells that transmit visual signals to the brain. Mitochondrial dysfunction results in decreased levels of ATP, the principal molecule for storing and transferring energy within cells. The decreased ATP levels, in turn, result in greater vulnerability of the Retinal Ganglion Cells (RGCs) and it is RGC death in response to stressful stimuli that represents the underlying cause of blindness in ADOA PYC's drug candidate works by increasing OPA1 protein levels in patient cells. The increase in OPA1 protein rescues mitochondrial function, increases ATP levels and enhances resistance to cell death. This drug candidate therefore has the potential to slow or even halt vision loss in ADOA patients.