Topical Losartan in Ophthalmology: Rationale, Experimental and Clinical Evidence, and Emerging Clinical Applications

Corneal fibrosis remains a major cause of visual morbidity, with transforming growth factor-β (TGF-β) signaling playing a central role in this process. Losartan, an angiotensin II type 1 receptor blocker widely used systemically for cardiovascular indications, has recently attracted interest in ophthalmology due to its antifibrotic properties through indirect inhibition of TGF-β signaling. In recent years, increasing experimental and early clinical evidence has suggested that topical ophthalmic formulations of losartan may attenuate corneal fibrosis following diverse injuries such as descemetorhexis, alkali burns, and photorefractive keratectomy-related injury. Topical losartan represents a promising, non-cytotoxic antifibrotic strategy in ophthalmology, although human evidence is limited and further randomized controlled clinical trials are required to define its clinical efficacy, optimal indications, timing, posology, formulations, and long-term safety. This review summarizes the biological rationale for the use of topical losartan in ophthalmology, including its molecular mechanisms of action, pharmacologic considerations, and safety profile. We critically review preclinical studies in corneal models, as well as emerging clinical applications.