Treatment efficacy of topical unoprostone isopropyl in patients with retinitis pigmentosa

A study was conducted by Dr Akiyama & associates from the Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, Fukuoka in Japan to evaluate the treatment effect of topical unoprostone isopropyl (unoprostone) (in the form of eye drops) on patients with retinitis pigmentosa (RP). This medication is currently used in glaucoma.

Forty patients with typical forms of RP were included in the study, out of which 17 patients were treated with 0.12% topical unoprostone twice daily in a randomly selected eye. The efficacy of the treatment was monitored by visual acuity and visual field testing using the Humphrey Field Analyzer (HFA). In addition, 12 RP patients who were included this study and 12 normal subjects were evaluated in terms of their macular blood flow of both eyes after instillation of unoprostone using the laser speckle method. 


One year after treatment, the 'macular sensitivity', calculated by HFA as the average sensitivity of the central 12 points, was preserved in the fellow eyes as well as the unoprostone-treated eyes. On the other hand, that in the eyes of the control RP patient was significantly decreased. Moreover, there were significantly greater improvements of the 'macular sensitivity' in the unoprostone-treated eyes than the fellow eyes. The change ratios of macular blood flow obtained from both RP patients and normal subjects were significantly increased in both the treated and the fellow eyes. No severe side-effects were observed. The authors conclude that the results demonstrate topical unoprostone may be efficacious in patients with RP as a consequence of the macular blood flow improvement as well as its direct neuroprotective effect.

Editor's note: We have been told that the article above was difficult to comprehend. Hence we requested our doctors to help make it simpler for non-experts to read. Hope the portion below helps. Thanks Ms Anjali Sharma, Bangalore.

So what does the study tell us?
In this study, application of unoprostone isopropyl (unoprostone) eyedrops to the RP eyes demonstrated the following:

1. The drug appeared to stabilize and/or improve the visual fields in the RP eyes that were treated, compared to the eyes of patients who were not treated with these eyedrops .
2. The other untreated (remember that only one eye of the patient had eyedrops applied to it) eye of the treated RP patients also showed some improvement, indicating the drug gets absorbed in the blood and reaches the other eye. But the effect was not as significant as in the treated eye - indicating that when approved for use, the eye drops will have to applied to each eye separately.
3. The macular blood flow also showed improvement in the treated RP patients compared to those not treated, which may potentially have a role to play in stabilizing or even reversing the disease.