title: Clinical performance of a mid-viscosity artificial tear for dry eye treatment.
abstract: OBJECTIVE
  We report the results of 3 studies conducted to evaluate the performance of a 1.0% carboxymethylcellulose (CMC) mid-viscosity artificial tear compared to currently marketed low-viscosity tears.
  
  
  METHODS
  First, a single-center, double-masked, randomized, crossover study was performed to compare the effect on the Ocular Protection Index (OPI) of the mid-viscosity tear compared to low-viscosity tears in 39 subjects with mild to moderate dry eye. Second, a 1-month, 2-arm, parallel, randomized double-masked clinical study assessed objective signs and subjective symptoms of dry eye in 103 subjects with mild to moderate dry eye. Third, in a 1-month home-use test, 465 artificial tear users compared the mid-viscosity tear or a current low-viscosity tear to their current artificial tear.
  
  
  RESULTS
  The OPI study showed prolonged tear breakup time and improved OPI for at least 20 minutes after instillation of the mid-viscosity tear. The low-viscosity tears showed improvements for 5 to 10 minutes. The 1-month clinical study showed a significant reduction in staining and dry eye symptoms after 1 week of treatment, with a further reduction in staining after 1 month in the mid-viscosity group. Subjects provided more reports of blur with the mid-viscosity tear than with a low-viscosity tear, but equivalent overall acceptability. The home use test showed general acceptability of the mid-viscosity tear, including more subjects indicating that it was needed less frequently than their prior low-viscosity tear.
  
  
  CONCLUSIONS
  This 1% CMC mid-viscosity tear showed protection of the ocular surface after instillation and significant reduction in signs and symptoms of dry eye. Improvements were greater than with low-viscosity tears. The mid-viscosity artificial tear was rated well in comfort, duration of benefit, and general acceptability.
authors.affiliation: Eye Care Research and Development, Allergan LLC, Irvine, CA 92612 , USA. simmons_peter@allergan.com
authors.forename: Peter A
authors.initials: PA
authors.lastname: Simmons
authors.forename: Joseph G
authors.initials: JG
authors.lastname: Vehige
mesh_terms: D002266:Carboxymethylcellulose Sodium / Q000008:administration & dosage* / Q000737:chemistry; D018592:Cross-Over Studies; D004311:Double-Blind Method; D015352:Dry Eye Syndromes / Q000188:drug therapy* / Q000503:physiopathology; D005260:Female; D006801:Humans; D065347:Hypromellose Derivatives; D008297:Male; D008747:Methylcellulose / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000737:chemistry; D008875:Middle Aged; D009883:Ophthalmic Solutions / Q000008:administration & dosage* / Q000737:chemistry; D011795:Surveys and Questionnaires; D013666:Tears / Q000502:physiology*; D014783:Viscosity
chemical_list: D009883:Ophthalmic Solutions; D065347:Hypromellose Derivatives; D008747:Methylcellulose; D002266:Carboxymethylcellulose Sodium