27. February 2023

New evidence of efficacy of transcorneal electrical stimulation (TES)

New analysis shows that OkuStim® therapy can slow progression in patients with retinitis pigmentosa (RP).

A new exploratory evaluation of a previous study has now provided further evidence of the effectiveness of OkuStim® therapy. The data show that after one year of TES treatment, visual field deterioration in patients with retinitis pigmentosa (RP) was slowed depending on the stimulation intensity.

Numerous approaches have been investigated in the past for the treatment of retinitis pigmentosa. At present, the possibilities of gene and stem cell therapy are being researched in particular, although little of this has been able to be adopted in clinical routine to date. OkuStim® therapy was used in 52 patients who participated in the study from 2011 – 2014. Retinal cells are stimulated by electrical impulses delivered from the outside – via the surface of the eye.

This “transcorneal electrical stimulation” (TES) worked in the study regardless of how advanced the patients’ visual field impairment was at the beginning of the therapy.

Of the patients included in the study (mean age: 46 years), 32 were treated with electrical stimulation between 0.1 and 1.0 mA in one eye at weekly intervals; 20 patients received sham treatment (placebo group). After one year of treatment, an average visual field decline of 2.1% was recorded in the TES-treated eyes and 5.8% in the (non-treated) fellow eyes, while the decline in the eyes from the placebo group was 7.5%. Thus, the decrease in visual field area measured by kinetic perimetry was 64% less in the eyes treated with TES than in the untreated eyes (p=0.013) and 72% less than in the placebo group (p=0.103). This slowing correlated with the strength of stimulation (p=0.047). Treatment was associated with transient mild dry eye symptoms in 23 stimulated patients.

According to the authors, slowing visual field decline with a neuroprotective therapy such as TES offers the chance to delay severe vision loss. It should therefore be used sensibly in patients as early as possible – as long as the centre of the retina is still largely intact and visual function is hardly impaired. The effect of TES in long-term use is being investigated in an ongoing study (Erprobungsstudie) (Kahle et al. 2021).

Here you can download the full press release on the current publication.

Click here to go directly to the publication.