chitosan-N-acetylcysteine

Chitosan-N-acetylcysteine (C-NAC) is a thiolated polymer derivative developed for the treatment of dry eye syndrome. It consists of a chitosan backbone chemically modified with N-acetylcysteine (NAC) moieties, which enables the polymer to exhibit strong mucoadhesive properties. This is achieved through the formation of covalent disulfide bonds between the thiol groups of the polymer and the cysteine-rich subdomains of mucins within the tear film. This interaction significantly increases the corneal residence time of the lubricant compared to standard ophthalmic solutions, providing long-lasting hydration and a protective barrier on the ocular surface. Clinical research led by Gerhard Garhofer at the Medical University of Vienna has evaluated its efficacy in stabilizing the tear film and reducing symptoms in patients with dry eye. The product is commercialized by Croma-Pharma and is often classified as a medical device in the European Union due to its primarily physical mode of action.

Brand names

Lacrimera

Other names

thiolated chitosanN-acetylcysteine-chitosan conjugateN-acetylcysteine-grafted chitosan