Letter to Editor: Light mask trial response

August 31, 2018

With reference to the Ophthalmology Times article titled "Light mask ineffective for diabetic macular oedema" published on 31st August, I am writing to make you aware of our grave concerns over the analysis and reporting of the CLEOPATRA study as we believe it presents a wholly false and inaccurate summary of the trial and the results.

The focus of our concern can be summarised as follows If a patient does not take a treatment they cannot derive any benefit: Only 4.5% of patients (7/155) enrolled into the trial consistently achieved or exceeded the compliance target.

There are 4 main areas identified within the published CLEOPATRA paper that are of major importance which are discussed in more detail in detail in the attached paper.
1. Questionable statistical model used for analysis – median percentage;
2. Very low mask usage/compliance; Only 4.5% of patients (7/155) enrolled into the trial consistently achieved or exceeded the compliance target
3. Patient management, communication and feedback processes;
4. Questionable interpretation of 12 month diffuse DMO benefit which was unsustained at 24 months.

On a positive note, the CLEOPATRA study did confirm that the light therapy is safe and also reported another key finding - that half way through the trial the light-masks significantly reduced diffuse diabetic macular oedema. The authors went on to note that this improvement seen at the 12 month mark, was not sustained at 24 months, concluding that the effect was transient and minimal. This was interpreted as a loss of efficacy of the intervention over time, but the analysis did not take into account that, compared with the first year, there was a significant drop in compliance during the second year potentially explaining the transient nature of the effect.

PolyPhotonix has repeatedly requested further post-hoc analysis, where an appropriate statistical model is used to analyse the effect of mask usage patterns.

PolyPhotonix has also submitted a correspondence letter to The Lancet and our full rebuttal document is available for your information.


-Moira Hopkins | Commercial Portfolio Manager, PolyPhotonix