Beneficial effects of a retinoic acid analog, CBS-211 A, on an experimental model of keratoconjunctivitis sicca.

We report the effects of CBS-211 A, a synthetic retinoic acid analog, on a previously described experimental model of keratoconjunctivitis sicca (KCS) in the rabbit. A 9-week topical treatment with 0.02% CBS-211 A in aqueous vehicle significantly increased the conjunctival goblet cell density (P less than 0.01, impression cytology counting), stopped the evolution of the corneo-conjunctival surface alteration (P less than 0.05, rose bengal test), and restored a basically normal mucosecretory product quality in goblet cells (lectin histochemistry) compared to vehicle treatment. The results assess the efficacy of this compound in reversing KCS pathology in a relevant model different from general vitamin A deficiency models, and strongly support the rationale for using such a well-tolerated retinoid in dry eye treatment.