Abstract
Abstract: :
Introduction: Pirenzepine (PIR) is a relatively selective M1–muscarinic antagonist which has been previously reported to inhibit myopic progression in children in two separate studies of one year duration (Siatkowski et al, ARVO Abstracts, Abs 4778, 2003 and Tan et al, ARVO Abstracts, Abs 801. 2003). We now report the 2–year safety and efficacy data of PIR 2% gel in the U.S. population. Methods: In a multi–centered (n=13), randomized, controlled clinical trial, children with myopia (–0.75D to –4.00D SEQ), aged 8–12 years, were assigned on a 2:1 basis to receive either PIR 2% gel (n=117) or placebo (PLC, n=57) b.i.d. for 1 year. The primary outcome measure, spherical equivalent refraction, was determined by cycloplegic autorefraction. Of these children, 84 (53 PIR vs. 31 PLC) elected to remain in the study for a second year. Results: The proportion of patients with ≥ 0.75D increase in myopia at 24 months was 37% (17/46) for PIR and 68% (19/28) for PLC (p < 0.01). Mean myopic progression over 24 months was –0.58 ± 0.53 D for PIR and –0.99 ± 0.68 D for PLC (p = 0.008). Over two years, 12% of PIR subjects and 0% of PLC subjects withdrew for adverse events. Common adverse events were eyelid gel residue, blurred near vision, and asymptomatic conjunctival reactions. Discussion: PIR 2% gel used bid in moderately myopic children reduced the rate of myopic progression over 2 years. The safety profile was acceptable and no study–related serious adverse events occurred. Thus, PIR appears to be an effective pharmacologic treatment for myopia.
Keywords: myopia • pharmacology • clinical (human) or epidemiologic studies: treatment/prevention assessment/controlled clinical trials