title: A 90-day study of the efficacy and side effects of 0.25% and 0.5% apraclonidine vs 0.5% timolol. Apraclonidine Primary Therapy Study Group.
abstract: OBJECTIVE
  To compare long-term intraocular pressure (IOP)-lowering efficacy of 0.25% and 0.5% apraclonidine hydrochloride with 0.5% timolol maleate.
  
  
  METHODS
  Multicenter, randomized, double-masked trial. Adult patients of either sex diagnosed as having open-angle glaucoma or ocular hypertension were enrolled following appropriate washout from all ocular hypotensive medications. Morning IOPs of 22 to 35 mm Hg were required for entry. Patients received 0.25% or 0.5% apraclonidine 3 times a day or 0.5% timolol twice a day for 90 days. Intraocular pressure was measured at 8 AM (before morning dosing) and at 4 PM (8 hours after dosing) on days 1, 30, and 90, and only at 8 AM on day 14.
  
  
  RESULTS
  All 3 medications significantly reduced IOP from baseline at all observation times (P < .001): 0.5% apraclonidine reduced IOP more than 0.25% apraclonidine; no significant difference was observed between 0.5% apraclonidine and 0.5% timolol 8 hours after dosing on days 1, 30, and 90; and a significant difference (P < .05) in favour of 0.5% timolol over 0.25% apraclonidine was observed 8 hours after dosing on day 30. At all morning visits following evening dosing, 0.5% timolol significantly reduced IOP more than both concentrations of apraclonidine.
  
  
  CONCLUSIONS
  Both 0.25% and 0.5% apraclonidine significantly reduce IOP when used as primary ocular hypotensive medication. Although 0.25% and 0.5% apraclonidine reduce IOP to a similar degree as 0.5% timolol 8 hours after morning dosing, neither concentration is as effective for reducing morning IOP after evening dosing.
authors.affiliation: Pharmaceutical Research Corporation, Charleston, SC, USA.
authors.forename: W C
authors.initials: WC
authors.lastname: Stewart
authors.forename: R
authors.initials: R
authors.lastname: Laibovitz
authors.forename: B
authors.initials: B
authors.lastname: Horwitz
authors.forename: R H
authors.initials: RH
authors.lastname: Stewart
authors.forename: R
authors.initials: R
authors.lastname: Ritch
authors.forename: M
authors.initials: M
authors.lastname: Kottler
mesh_terms: D000287:Administration, Topical; D000316:Adrenergic alpha-Agonists / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D003000:Clonidine / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000627:therapeutic use; D004311:Double-Blind Method; D005260:Female; D005902:Glaucoma, Open-Angle / Q000188:drug therapy*; D006801:Humans; D007429:Intraocular Pressure / Q000187:drug effects; D008297:Male; D008875:Middle Aged; D009798:Ocular Hypertension / Q000188:drug therapy*; D009883:Ophthalmic Solutions; D013999:Timolol / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*
chemical_list: D000316:Adrenergic alpha-Agonists; D000319:Adrenergic beta-Antagonists; D009883:Ophthalmic Solutions; D013999:Timolol; C016986:apraclonidine; D003000:Clonidine