S.T.O.P kit for Myopia Control: Stage 1 results from a randomized controlled clinical trial in Chinese children.

Purpose: The S.T.O.P kit provides a dynamic optical cue utilizing optical films on single vision (SV) spectacles. The study assessed the efficacy of two S.T.O.P kits (tests: Kit 1 and Kit 2) in reducing myopia progression against single vision spectacles without optical films (control).

Design: Prospective, multi-site, parallel-group, double-masked, randomized controlled trial.

Participants And Controls: 155 participants completed the study (n = 50, 52, and 53, in Kit 1, Kit 2, and control, respectively).

Methods: One hundred sixty eligible children aged 6-14 years with myopia between -0.75D and -5.00D and ≤1.50D astigmatism were enrolled at the Fudan University Eye & ENT Hospital and Tianjin Eye Hospital between December 2023 and February 2025. Participants were randomly assigned to wear Kit 1, Kit 2, or control. Axial length (AL) was measured at baseline, dispensing and at 1, 4 and 6 months after dispensing. Cycloplegic autorefraction was measured at baseline and after 6 months after dispensing. Differences between control and each test for changes in AL and cycloplegic M were analyzed using linear mixed models on the intention-to-treat population. Differences in visual acuity (VA) and subjective ratings were also assessed.

Main Outcome Measures: Change in AL from dispensing to the 6-month visit and change in cycloplegic M from baseline to the 6-month visit.

Results: After 6 months, both S.T.O.P kits showed significantly less change in AL than control (observed mean [standard error]: Kit 1: 0.083 [0.014] mm; Kit 2: 0.095 [0.014] mm; control: 0.169 [0.014] mm). The estimated least-square mean (LSM) differences (95% confidence intervals) compared with control were Kit 1: -0.091 mm (-0.131, -0.051); Kit 2: -0.090 mm (-0.130, -0.050). Both S.T.O.P kits also showed significantly less change in M than control (Kit 1: -0.189 [0.042] D; Kit 2: -0.214 [0.041] D; control: -0.315 [0.041] D). LSM difference: Kit 1: 0.135 (0.003, 0.268) D; Kit 2: 0.134 (0.001, 0.267) D. There were no significant differences between groups for VA or any subjective rating.

Conclusions: Both S.T.O.P kits showed significantly less myopia progression compared to control while maintaining good visual performance. The S.T.O.P kit's dynamic approach represents a promising strategy for myopia management.