24-hour Control of Intraocular Pressure (IOP) in Ocular Hypertension
Condition: Ocular Hypertension
MeSH terms: Ocular Hypertension; Glaucoma; Hypertension
Study type: Interventional
Phase: Phase 4

Summary: 
      This study was designed to compare the 24-hour efficacy on intra ocular pressure (IOP) of
      drugs acting either on aqueous humor production ("inflow drugs") or on aqueous humor outflow
      ("outflow drugs") in human eyes affected by ocular hypertension and virgin to treatment. The
      enrolled patients will be exposed, in a cross-over design, to n = 2 aqueous suppressants and
      n= 3 uveoscleral outflow enhancers, and 24 hr IOP will be measured. It is hypothesised that
      outflow drugs may offer a better and more stable control of IOP through the 24 hours.
    

Detailed description: 
      (a) study design: Prospective, open label, investigator-masked clinical trial, with
      cross-over design, both eyes treated, OD chosen for analysis; (b) study population: patients,
      showing ocular hypertension, who were never exposed to hypotensive treatment (see inclusion
      and exclusion criteria for details). (c) study drugs: Timolol and dorzolamide will be chosen
      as inflow drugs. The three prostaglandin analogues (PGA) Latanoprost, travoprost and
      bimatoprost will be chosen as outflow drugs. (d) study flow-chart: upon enrollment, patients
      will be initiated to the following schedule: 60 days timolol 0.5% bid, 60 days washout, 60
      days timolol 0.5%-dorzolamide 2% fixed combination bid, 60 days washout, 60 days PGA1, 60
      days washout, 60 days PGA2, 60 days washout, 60 days PGA3. Patients were assigned to the PGAs
      according to a sequence (L-T-B) randomly generated. Data will be collected at baseline and at
      the and of each study phase (i.e. active treatment and washout)(e) main efficacy outcome:
      change in the mean IOP (with respect to baseline) at the end of each study phase and change
      of IOP (with respect to baseline) at the different time points of the 24-hour phasing. IOP
      will be measured at 8 a.m., 11 a.m., 3 p.m., 6 p.m. and 9 p.m. by means of Goldmann
      applanation tonometry at the slit lamp. At midnight, 2 a.m. and 6 a.m. the Tonopen in supine
      position will be used. (f) statistics: the analysis of co-variance (ANCOVA) for paired
      samples with Bonferroni correction will be adopted. A minimum sample size of 51 patients is
      needed for a minimal expected difference in mean IOP between inflow and outflow drugs = 2.5
      mmHg, with an estimated pooled variance = 4 , a power = 90% and an alpha probability = 5%.
    

Intervention name(s): 0.5% timolol; timolol-dorzolamide fixed combination; Latanoprost; Travoprost; Bimatoprost
Intervention type(s): Drug; Drug; Drug; Drug; Drug
Other intervention name(s): timoptol (MSD); cosopt (MSD); xalatan (pfizer); travatan (Alcon); lumigan (Allergan)
Intervention MeSH terms: Timolol; Bimatoprost; Travoprost; Dorzolamide; Latanoprost
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Double (Investigator, Outcomes Assessor)
Primary purpose: Treatment
Keywords: glaucoma; 24-hour IOP; outflow drugs; inflow drugs