Xiaolan Chen1,2, Sujin Lee1, Tianyi Zhang1, Tianying Duan1, Neel D Pasricha3, Julie M Schallhorn3, Marc H Levin4, Vuk Koprivica5, Alan S Verkman1. 1. Department of Medicine and Physiology and University of California, San Francisco, California. 2. Jiangsu Agri-Animal Husbandry Vocational College, Taizhou, China. 3. Department of Ophthalmology, University of California, San Francisco, California. 4. Department of Ophthalmology, Palo Alto Medical Foundation, Palo Alto, California. 5. Vanda Pharmaceuticals, Inc., Washington, District of Columbia.
Abstract
Purpose: Dry eye disorders are a major health care burden. We previously reported the identification of N-methyl-N-phenyl-6-(2,2,3,3-tetrafluoropropoxy)-1,3,5-triazine-2,4-diamine [cystic fibrosis transmembrane conductance regulator (CFTR)act-K267], which activated human wild-type CFTR chloride conductance with EC50 ∼ 30 nM. Here, we report in vivo evidence for CFTRact-K267 efficacy in an experimental mouse model of dry eye using a human compatible ophthalmic vehicle. Methods: CFTR activation in mice in vivo was demonstrated by ocular surface potential difference (OSPD) measurements. Ocular surface pharmacodynamics was measured in tear fluid samples obtained at different times after topical administration of CFTRact-K267. Dry eye was produced by lacrimal duct cautery (LDC) and corneal epithelial injury and was assessed by Lissamine green (LG) staining. Results: OSPD measurements demonstrated a hyperpolarization of -8.6 ± 3 mV (standard error of the mean, 5 mice) in response to CFTRact-K267 exposure in low chloride solution that was reversed by a CFTR inhibitor. Following single-dose topical administration of 2 nmol CFTRact-K267, tear fluid CFTRact-K267 concentration was >500 nM for more than 6 h. Following LDC, corneal surface epithelial injury, as assessed by LG staining, was substantially reversed in 10 of 12 eyes receiving 2 nmol CFTRact-K267 3 times daily starting on day 2, when marked epithelial injury had already occurred. Improvement was seen in 3 of 12 vehicle-treated eyes. Conclusion: These studies provide in vivo evidence in mice for the efficacy of a topical, human use compatible CFTRact-K267 formulation in stimulating chloride secretion and reversing corneal epithelial injury in dry eye.
Purpose: Dry eye disorders are a major health care burden. We previously reported the identification of N-methyl-N-phenyl-6-(2,2,3,3-tetrafluoropropoxy)-1,3,5-triazine-2,4-diamine [cystic fibrosis transmembrane conductance regulator (CFTR)act-K267], which activated human wild-type CFTRchloride conductance with EC50 ∼ 30 nM. Here, we report in vivo evidence for CFTRact-K267 efficacy in an experimental mouse model of dry eye using a human compatible ophthalmic vehicle. Methods:CFTR activation in mice in vivo was demonstrated by ocular surface potential difference (OSPD) measurements. Ocular surface pharmacodynamics was measured in tear fluid samples obtained at different times after topical administration of CFTRact-K267. Dry eye was produced by lacrimal duct cautery (LDC) and corneal epithelial injury and was assessed by Lissamine green (LG) staining. Results: OSPD measurements demonstrated a hyperpolarization of -8.6 ± 3 mV (standard error of the mean, 5 mice) in response to CFTRact-K267 exposure in low chloride solution that was reversed by a CFTR inhibitor. Following single-dose topical administration of 2 nmol CFTRact-K267, tear fluid CFTRact-K267 concentration was >500 nM for more than 6 h. Following LDC, corneal surface epithelial injury, as assessed by LG staining, was substantially reversed in 10 of 12 eyes receiving 2 nmol CFTRact-K267 3 times daily starting on day 2, when marked epithelial injury had already occurred. Improvement was seen in 3 of 12 vehicle-treated eyes. Conclusion: These studies provide in vivo evidence in mice for the efficacy of a topical, human use compatible CFTRact-K267 formulation in stimulating chloride secretion and reversing corneal epithelial injury in dry eye.
Authors: Jennifer P Craig; Kelly K Nichols; Esen K Akpek; Barbara Caffery; Harminder S Dua; Choun-Ki Joo; Zuguo Liu; J Daniel Nelson; Jason J Nichols; Kazuo Tsubota; Fiona Stapleton Journal: Ocul Surf Date: 2017-07-20 Impact factor: 5.033
Authors: William Stevenson; Yihe Chen; Sang-Mok Lee; Hyun Soo Lee; Jing Hua; Thomas Dohlman; Tina Shiang; Reza Dana Journal: Cornea Date: 2014-12 Impact factor: 2.651
Authors: Neel D Pasricha; Alex J Smith; Marc H Levin; Julie M Schallhorn; Alan S Verkman Journal: Transl Vis Sci Technol Date: 2020-10-15 Impact factor: 3.283