[Clinical study of silicone hydrogel multifocal soft contact lenses for correction of presbyopia]

Objective: To evaluate the efficacy and safety of a novel silicone hydrogel multifocal soft contact lens for presbyopia correction, and to verify its non-inferiority compared with a conventional hydrogel multifocal contact lens. Methods: This was a prospective, randomized, open-label, parallel-group, multicenter non-inferiority clinical trial. From October 2024 to July 2025, 195 presbyopic subjects aged ≥40 years with near add power of +0.75 to +2.50 D were screened at 5 centers (Eye Hospital of Wenzhou Medical University, Eye & ENT Hospital of Fudan University, and Shenzhen Eye Hospital, Qingdao Eye Hospital of Shandong First Medical University, and Shanxi Eye Hospital Affiliated to Shanxi Medical University), and 180 were enrolled and randomized (computer-generated random number method) 1∶1 to the test group (samfilcon A silicone hydrogel multifocal soft contact lens, n=90) or the control group (polymacon hydrogel multifocal soft contact lens, n=90). Both type of lenses were monthly disposable for daily wear. Binocular corrected distance visual acuity (5 m) and near visual acuity (40 cm) were measured at each visit using a standard logarithmic visual acuity chart (5-point recording method). Subjective wearing experience was assessed by a validated acceptability questionnaire, and ocular surface status was evaluated via tear break-up time (TBUT) and corneal fluorescein staining. The primary endpoint was the wearing success rate at 1 week, defined as binocular corrected distance visual acuity ≥4.9 and near visual acuity ≥4.7. Missing values were imputed using the worst observation carried forward method. Rate differences and 95% confidence intervals (CI) were calculated by the Newcombe-Wilson method. Between-group comparisons were performed using Fisher exact test, independent-samples t test, or Wilcoxon rank-sum test. Sensitivity analysis was performed using the Cochran-Mantel-Haenszel method stratified by center. The non-inferiority margin was prespecified as -10%. Results: The full analysis set comprised 177 subjects (87 in the test group, 90 in the control group), with a mean age of (47.1±4.7) years, including 33 males and 144 females. After the data imputation, the wearing success rate at 1 week was 100.0% in both groups, with a rate difference of 0.00% (95%CI:-4.23% to 4.09%), meeting the non-inferiority criterion. Sensitivity analysis of raw data showed success rates of 96.6% and 96.7% in the test and control groups, respectively (adjusted rate difference -0.00%, P=0.991), consistent with the primary analysis. At all visits, binocular corrected visual acuities were within normal ranges in both groups, with no significant between-group differences (all P>0.05). Contact lens-corrected visual acuity was slightly lower than best spectacle-corrected visual acuity in both groups, with mean differences of approximately 0.03 to 0.06. The test group had a higher proportion of"excellent"subjective distance vision ratings at 1 week (50.0% vs. 36.8%, P=0.047), better comfort at 1 week and 1 month (both P<0.05), and better lens cleanliness at dispensing and 1 week (both P<0.05). Subjects with low add power had better total subjective scores at 1 week [2.0 (0.0, 4.0) vs. 4.0 (2.0, 5.0), P=0.004], with no significant difference at 3 months. At 1 month, the test group showed a smaller decrease in TBUT from baseline (P<0.05) and a higher proportion of grade 0 corneal fluorescein staining at 1 week and 1 month (both P<0.05); these differences disappeared by 3 months. No device-related serious adverse events occurred, and the incidence of adverse events did not differ significantly between groups. Conclusions: The novel silicone hydrogel multifocal soft contact lens is non-inferior to the conventional hydrogel lens in presbyopia correction, with a comparable safety profile and superior comfort, subjective experience, and short-term ocular surface protection. It can serve as an effective correction option for presbyopic populations.