Active clinical trials for "Retinitis"

Retinitis pigmentosa (RP) is an inherited retinal disease with great heterogeneity. RP comprises a large group of genetic disorders causing progressive loss of vision. Despite many suggested treatments, there is actually no effective therapy for most types of RP at present. Mutations that cause RP initially lead to rod cell death. After rod photoreceptors' death, cone photoreceptors also gradually die. There are several hypotheses as to why mutation-induced rod photoreceptor cell death invariably leads to gradual dysfunction and death of cone photoreceptors resulting in severe visual acuity loss and blindness. Rods constitute 95 percent of cells in the outer retina. As they degenerate, oxygen consumption is reduced and the level of tissue oxygen markedly increases. After rods degeneration, several markers of oxidative damage appear in cones. This oxidative stress over time may lead to cone dysfunction and death. Antioxidants reduce markers of oxidative damage and promote cone function and survival. In RP, cone death occurs as a result of the death of rods, rather than as the result of the pathogenic mutations and therefore treatment with antioxidants may have the potential to be applied to all patients with RP irrespective of the disease-causing mutation. N-acetylcysteine is a derivative of L cysteine that plays a role in the biosynthesis of glutathione and neutralizes reactive oxygen species. It also has a direct antioxidant activity via its reactive sulfhydryl agent. Its systemic use shows an acceptable safety profile. It has been shown that the use of systemic N-acetylcysteine provides significant intraocular concentration and antioxidant activity that may lead to the promotion of cone function and survival. In a recent phase 1 randomized clinical trial (RCT), it was revealed that oral N-acetylcysteine (NAC) was safe and well-tolerated in patients with moderately advanced RP and might improve sub-optimally functioning macular cones. The authors concluded that a randomized, placebo-controlled trial is needed to determine if oral NAC can provide long-term stabilization and/or improvement in visual function in patients with RP. In this phase 2 RCT, eligible patients with the diagnosis of moderately advanced RP are randomly divided into two groups; treatment group (N-acetylcysteine tablets) and controls (placebo). Each group will be treated for 6 months. In this study, we will investigate if the use of oral N- acetylcysteine as a potent antioxidant agent can slow down or reverse the disease process in RP patients with prior moderate loss of vision. It may potentially demonstrate a treatment modality regardless of the genetic type of RP. The primary outcome measure will be the stability or improvement of the best-corrected visual acuity (BCVA). The secondary outcome measures will be changes in color vision, electroretinogram, visual field, structural OCT indices after 6 months. The same parameters will be re-evaluated 3 months after discontinuation of treatment at month 9.

Incomplete Closed Protocol

Identify new genes responsible for autosomal dominant retinitis pigmentosa (ADRP), one of the most common causes of hereditary diseases of the retina, and thus better understand the mechanisms involved of the disease."

This study is being done to determine if wearable text-to-speech (TTS) and visual pattern recognition (VPR) technology can be used to extend the capabilities of the Argus II to allow patients to read and recognize faces and objects. The Argus II retinal prosthesis can restore rudimentary forms of vision to patients with bare light-perception vision. Using the prosthesis, patients can identify obstacles, handles, switches, eating utensils and demonstrate improved navigation when used in conjunction with other ambulation-assist tools. Current limits in the resolution of the device prevent useful reading or face recognition. The FDA has approved the Argus II as a humanitarian device. Present-day wearable text-to-speech converters are also capable of object and face recognition. Such systems have been developed to assist with these tasks in patients with severe low-vision. ORCAM is a commercially-available eyeglass-mounted visual pattern recognition system capable of converting photographs of text to speech. It is comprised of a camera, a small belt-worn computer, pattern recognition software and a small audio transducer. ORCAM can acquire the image of a sheet of paper and read the text to the user through a small speaker adjacent to the ear. In addition, ORCAM can be trained to recognize faces and speak the name of the individual to the user. ORCAM can also be used to recognize everyday products after being programmed.

The development of new oculometry techniques allows fine and dynamic measurements of pupillary diameter and use in routine clinical practice. The preliminary results obtained with innovative devices on healthy sjuets make it possible to envisage a clinical study on a population of patients suffering from retinal pathologies. This is a "proof of concept" study, which, if the expected results are confirmed, will make it possible to consider a study on a larger population, as well as the industrial development of a commercial device.

The objective of the study is to gain a better understanding of disease progression over time in participants with X-linked retinitis pigmentosa (XLRP).

To monitor trends over time, in the incidence of CMV retinitis and other ocular complications of AIDS To determine the effect of highly active anti-retroviral therapy (HAART)-induced immune status on the risk of developing CMV retinitis and other ocular complications of AIDS To determine the characteristics (clinical, virologic, hematologic, and biochemical) of a population at high risk for CMV retinitis and other ocular complications of AIDS To evaluate the effects of treatments for CMV retinitis and other ocular complications on visual function, quality of life, and survival.

This is a post-market study of the Argus II Retinal Prosthesis System. The study is being conducted in France. The objective of the study is to obtain data to further demonstrate the effectiveness and evaluate the safety of Argus II System in patients with retinitis pigmentosa who have a bare light perception or worse in both eyes.

This study evaluates a novel collision warning device to help people with severe vision impairment or blindness avoid collisions with obstacles. The main hypothesis to be tested is that the device reduces the number of collisions with obstacles in everyday activities.

In this retrospective non-interventional study (NIS), the subjective and objective benefit of patients with retinitis pigmentosa (and other dystrophies like Usher, Choroideremia or cone-rod dystrophy), who have been prescribed the therapy of transcorneal electrostimulation (TcES) with the OkuStim System, is assessed.