Statistics from Altmetric.com
Editor,—Latanoprost 0.005% is a prostaglandin analogue that causes reduction of the intraocular pressure (IOP) by increasing the uveoscleral outflow of aqueous humour through the ciliary muscle region to the suprachoroidal space and the episcleral veins.12 Initial studies on latanoprost demonstrated reductions of 20% to 40% in the IOP of normotensive volunteers, patients with ocular hypertension, and glaucoma patients.3-10 The efficacy of latanoprost 0.005% in lowering the intraocular pressure (IOP) in different glaucoma populations, especially when added to anti-glaucoma medications already being used, however, is not well established. The effectiveness of latanoprost in lowering the IOP in glaucomatous eyes with uncontrolled IOP that were already receiving maximal tolerated medical treatment was evaluated.
All patients who used latanoprost as compassionate treatment at Wills Eye Hospital/Jefferson Medical College in 1995 and 1996 and had at least 1 month of follow up were evaluated (n = 24). In patients treated with latanoprost in both eyes, only the right eye was chosen for this study. Criteria for success were defined before data collection. Complete success was defined as a reduction of the IOP >20%; relative success was defined as any reduction of the IOP. Kaplan–Meier analysis and Student’s t test were used for data analysis.
Twenty four patients were evaluated with a mean age of 77.9 (SD 9.3) years. There were 14 (58.3%) females and 10 (41.7%) males, most of them being (n=19, 79.1%) white. The most frequent diagnosis (n=17, 70.8%) was primary open angle glaucoma (POAG). Most patients (n=18, 75.0%) were using two or more anti-glaucoma medications. Baseline IOP (21.4 (SD 5.6) mm Hg) was reduced after 1 and 3 months to 16.5 (3.8) mm Hg (p<0.001) and 16.4 (3.7) mm Hg (p<0.001), respectively. The probabilities of complete and relative success at 3 months’ follow up were 26.7% and 87.0%, respectively (Figs 1 and 2). Latanoprost was discontinued in three patients (12.5%) because of problems that appeared after the treatment was started—bronchitis, throat irritation, and myocardial infarction. The first two cases may have been related to local irritation from the medication.
This report suggests that the use of latanoprost slightly lowers the IOP in most glaucomatous patients already receiving maximal tolerated medical treatment. However, the reduction reaches a target level of > 20% less than the baseline IOP in fewer cases, approximately 1/4 of patients.
Each author states that s/he has no proprietary interest in the development or marketing of this or a competing drug.