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No “long-term therapeutic benefit” from £250 mask

A two-year trial across 15 NHS sites does not support the use of a light emitting mask for patients with diabetic eye disease

A man sleeping

A phase three trial involving 308 patients across 15 NHS sites has found that a light-emitting mask conveys no “long-term therapeutic benefit” for those living with early diabetic macular oedema.

However, the chief executive of a company that produces the mask says the results are an indication of poor patient compliance rather than an ineffective device.

The findings of the randomised controlled trial, referred to as the CLEOPATRA study, are published in The Lancet Diabetes & Endocrinology. 

The study, which was funded by the National Institute for Health Research, saw 155 patients issued with a Noctura 400 Sleep Mask manufactured by PolyPhotonix Medical.

A further 153 patients received an ‘sham’ mask that does not emit light.

All of the patients had non-central diabetic macular oedema and were advised to use the mask every night according to the instructions provided.

At the end of the two-year period, the researchers concluded that the study does not support the use of the device.

They also found that the compliance level of patients wearing the light mask decreased over time.

A spokesperson for Moorfields Eye Hospital NHS Foundation Trust told OT: “The light masks used in this study did not provide any therapeutic benefits for treating or preventing the progression of non-central diabetic macular oedema.”

PolyPhotonix responds

The Noctura 400 Sleep Mask is sold by PolyPhotonix at a cost of £250 and lasts three months.

The company received an award of £1.4 million to develop the technology from the Small Business Research Initiative on behalf of NHS England.

PolyPhotonix chief executive, Richard Kirk, told OT that his company is submitting a “full rebuttal” to The Lancet Diabetes & Endocrinology article.

“We are naturally very disappointed with the publication of the Cleopatra paper,” he shared.

“We do however believe that its conclusions are flawed and are not a reflection of the efficacy of Noctura treatment,” Mr Kirk emphasised.

He highlighted that only a small proportion of patients consistently achieved or exceeded the compliance target, and coaching of the patients to wear the mask was “very limited.”

“Fundamentally, what this trial shows is that if patients don’t wear the mask they derive no benefit,” he observed.

Mr Kirk stressed that PolyPhotonix did not have input into the design of the trial or its management.

The study has not affected the company’s commitment to providing Noctura as a first line therapy for patients diagnosed with diabetic eye conditions.

“We especially want to focus on countries where injections are costly and many patients still endure visual impairment due to a lack of resources for diabetic patients,” Mr Kirk shared.

“Robust” data

A comment on the Cleopatra study published in the same edition of The Lancet Diabetes & Endocrinology observed that the “robustness” of the data does not support the need for another trial.

Tien Yin Wong, of the Singapore Eye Research Institute, highlighted: “The search for elegant, novel, non-invasive treatments for diabetic retinopathy and diabetic macular oedema continues.”

Diabetes UK director of health intelligence and professional liaison, Simon O’Neill, told OT that the best way to reduce eye problems in people with diabetes is to ensure that they have good blood glucose control and attend regular eye screenings.

“While research suggests the light emitting sleep mask might not be beneficial in preventing the progression of diabetic macular oedema, there are a number of other treatment options available for people with the condition. Decisions about treatment options should be discussed in partnership between the person with diabetes and their healthcare team,” he shared.

Corporate partnership

A spokesperson for Fight for Sight confirmed that the charity previously had a corporate partnership with PolyPhotonix which concluded in 2017.

PolyPhotonix donated 5% of the price of each Noctura device to Fight for Sight.

However, the spokesperson clarified that Fight for Sight has not endorsed the product.

“Fight for Sight doesn’t endorse any particular products or services but we do, on occasion and after careful due diligence, enter into fundraising partnerships to support innovative research into sight loss and eye health conditions.” 

Image credit: Polyphotonix