Acucela has reported new safety, tolerability and effectiveness data on ACU-4429, an investigational therapy for dry age-related macular degeneration.

According to Acucela, study participants tolerated ACU-4429 well in single-dose tests conducted with healthy volunteers aged 55–80.

Acucela CEO and founder Ryo Kubota said: “Many companies have worked diligently to find a successful treatment for this devastating disease. Our early data shows that ACU-4429 has the potential to be a breakthrough treatment.”

Using ERG as a biomarker to measure rod-mediated retinal activity and function, inhibition of the b-wave followed administration of ACU-4429 and exposure to full-field bleach. This effect was seen on the day of dosing. All ERG measurements returned to baseline levels by day seven after dosing.

Preclinical data indicated that ACU-4429 slows the rod visual cycle, resulting in decreased accumulation of a toxic byproduct that is the precursor of lipofuscin. The chronic accumulation of lipofuscin has been implicated in pathological mechanisms that lead to degenerative retinal diseases.

ACU-4429’s mechanism of action is an indication of its potential therapeutic effect on these disorders, which include dry age-related macular degeneration (AMD) and Stargardt’s disease.

Acucela is developing ACU-4429 as a single-dose daily oral treatment for dry AMD, the most common form of the disease. Currently, there is no approved medicinal therapeutic treatment for dry AMD. Data shows ACU-4429 may potentially slow or halt the progression of dry AMD. ACU-4429 is in Phase I trials, and a Phase II trial is expected to begin later in 2009.