New four-year study data has recently been released which appears to show the significant impact of a soft contact lens management approach to slowing the progression of myopia in children, including those whose treatment begins at a later age.
CooperVision presented the findings at the recent BCLA Asia conference in Singapore at which the increasing prevalence of myopia worldwide was one of the most widely discussed issues.
MiSight trial
Dual focus contact lenses have been available for some time. They work by correcting the on-axis refractive error fully but also create a hyperopic defocus in the periphery which is thought to slow down the axial length growth of the eye which results in increasing myopia. Such a lens is the CooperVision MiSight, currently commercially available in selected countries, including the UK (figure 1).
The ongoing clinical trial has been running now for four years and is designed to assess the impact of this dual-focus myopia control 1-day soft contact lens in reducing the rate of progression of juvenile-onset myopia.
After year three, results presented at the BCLA Conference in Liverpool showed myopia progression had slowed in children wearing the MiSight contact lens: by 59% as measured by mean cycloplegic spherical equivalent and by 52% as measured by mean axial elongation of the eye when compared to the children in the control group wearing a standard design single vision 1-day soft contact lens.
The new results at year four include those of children from the original control group who had been refitted with the myopia control lens, and who were then tracked separately. Use of the dual-focus contact lens (which has alternating visual correction and treatment zones) was effective in slowing myopia progression in both groups as follows:
- There was a significant reduction in myopic progression for the previous single vision 1-day wearers, indicating that MiSight is also effective when beginning myopia management at an older age.
- There were no significant differences between groups for changes in spherical equivalent refractive error and axial length over 12 months.
- Axial length growth of 0.07mm in the MiSight group and 0.06mm in the previous control group, compared to 0.10mm seen in the MiSight group in year three, represents further myopia slowing as the children age.
- There were no significant differences in myopia progression rates for two demographically matched populations in their first versus four years of MiSight lens wear.
Paul Chamberlain, director of research programmes for CooperVision and lead trial researcher, said: ‘Four-year results on the efficacy of our innovative myopia control lens represent a landmark in slowing myopia progression. The treatment is continuing to work for children who have been wearing MiSight for the entire study, and their axial length progression in this last year has slowed further. This illustrates the benefits of beginning myopia management as early as possible to maximise the benefit.’
No other prospective randomised controlled study has offered such conclusive data for this degree of continued efficacy in myopia management using a 1-day soft contact lens over four years. Furthermore, the contact lens-based approach does not induce common side effects exhibited by some alternative pharmacological therapies (such as atropine).
Stuart Cockerill, senior director of myopia management for CooperVision, said: ‘The four-year results are another great learning for CooperVision and the entire optical industry on the capability to slow the progression of myopia in children. Though children benefit at whatever age the treatment is started, the sooner their myopia is managed with MiSight, the more effect and benefit they receive in reducing final levels and the future risk of related vision impairment issues.’
The future
As more practitioners become interested in myopia intervention, these results showing promise from an easily fitted and well accepted contact lens option makes the evolving clinical approach more attainable in practice. I await further data with great interest.
