Study indicates for the first time that latanoprost eye drops preserve vision in patients with open-angle glaucoma. Treatment with latanoprost reduces intraocular pressure, and attenuates loss of vision.
Increased pressure in the eye (intraocular pressure) can lead to optic nerve damage, resulting in glaucoma and permanent loss of vision. The most common form of glaucoma, open-angle glaucoma, is associated with high intraocular pressure. Progressive nerve damage is caused by this increased pressure, which causes gradual loss of vision beginning from the mid-peripheral visual field and spreading to the central visual field. Treatments aimed at reducing intraocular pressure are therefore used to treat glaucoma. Latanoprost is a prostaglandin analog that acts by increasing the fluid drainage inside the eye, thereby reducing intraocular pressure.
A recent study, The United Kingdom Glaucoma Treatment Study (UKGTS), aimed to determine the extent of vision preservation achieved in study participants who were treated with latanoprost compared to those given placebo treatment. The study enrolled 516 patients across 10 centres in the UK and randomly assigned them to receive either latanoprost eye drops once daily in both eyes, or placebo drops once daily in both eyes.
Results of the study demonstrated that treatment with latanoprost significantly reduced intraocular pressure, and increased the time to vision deterioration in the treatment group when compared with the placebo group. While 25% of participants in the placebo group had reached the visual deterioration endpoint at 24 months, only 15% of participants in the treatment group reached deterioration in the same period of time. This study was the first to demonstrate attenuation of vision loss due to glaucoma in patients treated with latanoprost.
Generic Version of Latanoprost (NCT02047630)
A generic version of latanoprost is currently being evaluated for effectiveness and tolerability compared with brand-name latanoprost at the Centre Hospitalier Universitaire de Quebec, CHU de Quebec, in Canada. Participants with open-angle glaucoma who are 18 years or older with primary open angle glaucoma are currently being recruited to the phase 4 study; participants must have an intraocular eye pressure of more than 21mmHg. The primary outcome of the study will be a change in intraocular pressure and participants will undergo two study periods of 8 weeks each. In the first 8 weeks the participants will use brand-name latanoprost in one eye and the generic version in the other eye. During the second eight week period the participants will switch from one eye to the other. Participants will be followed up for a period of 4 months.
Slow Release Version of Latanoprost (NCT02129673)
A phase 1 and 2 clinical trial assessing the safety and effectiveness of a slow release version of latanoprost is also currently recruiting participants. VS101 is a subconjunctival latanoprost insert that lasts for 3 months. The study is being conducted at the Specialty Eyecare Centre, Bellevue, Washington, United States, and is recruiting participants who are at least 18 years old and have open-angle glaucoma or ocular hypertension.
Latanoprost (Xalatan) Information Sheet. Available from: http://www.xalatan.com/high-eye-pressure-glaucoma Last Accessed Jan 7, 2015.
Garway-Heath, DF,Crabb, DP,Bunce, C,Lascaratos, G,Amalfitano, F,Anand, NAzuara-Blanco, A Bourne, RR, Broadway, DC,Cunliffe, IA, Diamond, JP, Fraser, SG, Ho, TA, Martin, KR,McNaught, AI, Negi, A, Patel, K, Russell, RA,Shah, A,Spry, PG,Suzuki, K,White, ET,Wormald, RP. “Latanoprost for open-angle glaucoma (UKGTS): a randomised, multicentre, placebo-controlled trial” The Lancet December 2014. doi:10.1016/S0140-6736(14)62111-5
Clinicaltrials.gov “Efficacy of the Brand-name Latanoprost and One of Its Generic Version in Primary Open Angle Glaucoma and Ocular Hypertension” Available from: https://www.clinicaltrials.gov/ct2/show/NCT02047630?term=latanoprost&recr=Open&no_unk=Y&rank=1Last Accessed: Jan 7, 2015.
Clinicaltrials.gov “A Phase 1/2 Multicenter, Randomized, Study to Evaluate the Safety and Efficacy of VS101 SubconjunctivalLatanoprostInsert in Subjects With Open-Angle Glaucoma or Ocular Hypertension” Available from: https://www.clinicaltrials.gov/ct2/show/NCT02129673?term=latanoprost&recr=Open&no_unk=Y&rank=2 Last Accessed: Jan 7, 2015.
Image courtesy of renjith krishnan at FreeDigitalPhotos.net
Written by Deborah Tallarigo, PhD