Control of myopia using diffusion optics spectacle lenses: 4-year results of a multicentre randomised controlled, efficacy and safety study (CYPRESS)

• Published in: BMJ open ophthalmology 2024-10, Vol.9 (1), p.e001790
• Main Authors: Laughton, Deborah, Hill, Jennifer S, McParland, Marcella, Tasso, Vanessa, Woods, Jill, Zhu, Xiaoying, Young, Graeme, Craven, Ruth, Hunt, Chris, Neitz, Jay, Neitz, Maureen, Chalberg, Thomas W, Jones, Deborah, Wolffsohn, James S
• Format: Article
• Language: English
• Subjects: Age; Axial Length, Eye; Child; Child health (paediatrics); Clinical Trial; Clinical trials; COVID-19; COVID-19 - epidemiology; COVID-19 - prevention & control; Demographics; Disease transmission; Double-Blind Method; Eyeglasses; Female; Follow-Up Studies; Global health; Humans; Male; Myopia; Myopia - therapy; Optics; Original Research; Public health; Refraction, Ocular - physiology; Treatment Outcome; Visual Acuity
• ISSN: 2397-3269; 2397-3269
• DOI: 10.1136/bmjophth-2024-001790

AimsTo evaluate the myopia control efficacy of Diffusion Optics Technology (DOT) spectacle lenses in children over a 4-year treatment period.MethodsCYPRESS Part 1 (NCT03623074) was a 3-year multicentre, randomised, controlled, double-masked trial comparing two investigational spectacle lens DOT designs (Test 1, Test 2) and standard single vision Control lenses in 256 North American children aged 6–10 years. Children completing Part 1 (n=200) were invited to enrol in CYPRESS Part 2 (NCT04947735) for an additional 1-year period. In Part 2, Test 1 (n=35) and Control groups (n=42) continued with their original lens assignment and the Test 2 group (n=21) were crossed over to Test 1 (DOT 0.2) lenses. The co-primary endpoints were change from baseline in axial length (AL) and cycloplegic spherical equivalent refraction (cSER).ResultsTest 1 spectacle lenses demonstrated superiority to the Control in both co-primary endpoints: with a difference between means (Test 1−Control) of −0.13 mm for AL (p=0.018) and 0.33 D for cSER (p=0.008) in Part 1 and −0.05 mm for AL (p=0.038) and 0.13 D for cSER (p=0.043) in Part 2. Comparing treatment effects in Part 1 and 2 suggests that COVID-19 public health restrictions negatively impacted treatment efficacy in study years 2 and 3.ConclusionDOT 0.2 spectacle lenses are safe and effective at reducing myopia progression, with additional benefit evident in year 4 of wear. These results support the hypothesis that a mild reduction in retinal contrast can slow myopia progression in young children. The unprecedented disruption in participant schooling and lifestyle during the COVID-19 pandemic may have depressed treatment efficacy in Part 1.