Risarestat (CT-112) is a potent aldose reductase inhibitor and thyroid hormone receptor (TR) antagonist for the treatment of hypoglycemia.

In a dose-dependent manner, Risarestat inhibits the accumulation of dulcitol, with the exception of the 1.0% solution, which exhibits activity comparable to the 0.25% solution[1]. Following instillation, Risarestat peaks in the corneal epithelium, stroma, endothelium, and aqueous humor within 30 minutes, gradually diminishing time-dependently over 24 hours. Risarestat remains detectable in the lens for up to 24 hours, with a peak concentration observed at 2 hours after instillation[2]. In the group treated with Risarestat, the anterior surface area of superficial cells significantly decreases from a mean value of 881 to 728 microns^2. Corneal sensitivity significantly improves from 5.36 to 1.37 g/mm^2[3]. Animals treated with Risarestat show a significant increase in the mean blink response compared to untreated galactose-fed rats, and the response does not differ significantly from controls toward the completion of the 7-month study. However, animals treated topically with Risarestat and untreated galactose-fed rats develop bilateral nuclear cataracts within 3 weeks[3].