R-Tech Ueno announces end of phase 3 study with Unoprostone ophthalmic solution to treat retinitis pigmentosa
R-Tech Ueno, a bio venture company, announced the end of a phase 3 clinical study with Unoprostone (development code UF-021) ophthalmic solution that are being developed in the company for the treatment of retinitis pigmentosa and the preliminary findings from a phase 3.
The phase 3 clinical study with UF-021 ophthalmic solution for treatment of retinitis pigmentosa (ClinicalTrials.gov Identifier:NCT01786395), for which an effective therapy has not been currently established, was a multicenter study using a placebo (without the active ingredient) as a control carried out based on Good Clinical Practice (GCP) in patients with visual field constriction and then deterioration of vision. This was a randomized double-masked controlled study for 52 weeks for efficacy, followed by the open trial study of UF-021 for a further 52 weeks for safety. The target sample size was 180 patients and the study was carried out at 38 sites nationwide.
The primary endpoint of the study was the changes in the value of the mean retinal sensitivity at four central points through HFA (10-2). The difference compared to the placebo group was not statistically significant.
However, the primary endpoint and visual acuity of UF-021 group demonstrated improvement compared to Day 0 (before the study) and the difference was statistically significant. On the other hand, the Goldmann visual field of the placebo group progressed statistically and significantly the constriction of the visual field compared to Day 0. Furthermore the total score of VFQ-25 was found to have improved statistically and significantly in the UF-021 group.
We confirmed the therapeutic effectiveness of UF-021 ophthalmic solution for Retinitis Pigmentosa through the present phase 3 clinical study in Japan, but as the primary endpoint at the end of study was not statistically significant, we are analysing the data from various angles and examining possibility of the new drug application to MHLW as best we can now. And we decided to close the open trial study of UF-021 for a further 52 weeks for safety in the view of objectivity of the data obtained.
Regarding the impact of this matter on the company’s full-year results, no changes are to be made on the full-year business result forecasts released on February 12, 2015.
Prostones, a class of functional fatty acids which were first discovered in the 1980s by Dr. Ryuji Ueno, the founder of R-Tech Ueno, are compounds having effective localized physiological action as drugs, while being largely without the various systemic adverse reactions of prostaglandins themselves. Rescula Eye Drops 0.12 per cent (generic name: unoprostone isopropyl), which obtained market approval in 1994 for treatment of glaucoma and ocular hypertension, was the world’s first prostone drug. It opens ion channels (BK channel or Maxi-K channel)
and not only lowers intraocular pressure, it is also reported to protect optic nerves (in vitro) and improve ocular blood flow in normal tension glaucoma. Since its release in 1994, it has been approved in 45 countries. In 2009 the concentration of preservative contained in Rescula Eye
Drops 0.12 per cent was reduced by a change in the formulation, and in 2010 storage at room temperature instead of in a cold place became possible. Rescula Eye Drops 0.12 per cent is also marketed in South Korea and Taiwan.
Retinitis pigmentosa is a hereditary disease and its prevalence rate is said to be about 1 in 5000 people in the world including– Japan. When this number is applied to the population of Japan, 126 million people, the number of patients with retinitis pigmentosa can be estimated as 30,000 people, which makes this disease an orphan disease. On the other hand, when projecting the number of patients with retinitis pigmentosa in the world from the world population, 6.94 billion people (World Health Statistics 2013 published by WHO), it can be estimated as 1.39 million people. When retinitis pigmentosa progresses, patients suffer progressive night blindness, where it becomes difficult to see in dim light, or visual field constriction and then deterioration of vision. In the end stage, they may suffer from severe visual loss or even blindness. It is designated as an intractable disease and appropriate therapeutic drugs or therapeutic methods have not been established at the moment. According to the report by the “Research Study Group Regarding Chorioretinal and Optic Atrophy”, a specified disease treatment research program of the Ministry of Health, Labour and Welfare (MHLW), retinitis pigmentosa is the 3rd cause for impaired vision and especially in patients aged 60 or under it is the leading cause for impaired vision.
Some diseases are very difficult to treat, they chronically develop, leave after-effects and make it extremely difficult or impossible for the patient to return to society, require a high medical cost, cause a heavy burden both domestically and mentally such as financial problems and nursing care and furthermore, as they are rare diseases they need to be studied on a nationwide scale. MHLW designates such diseases as intractable diseases. Currently, 130 diseases are designated as intractable diseases. Retinitis pigmentosa is a research target of the clinical research study area of the Research for Overcoming Intractable Diseases, MHLW. Disease number 33. Additionally, among the 130 intractable diseases, 56 are accredited as “specified diseases” and receive public fund assistance for medical expenses. Retinitis pigmentosa is one of the “specified diseases” and is covered by public fund assistance for medical expenses. Diseases subsidised for medical expenses of designated intractable diseases: disease number 37.
R-Tech Ueno is a bio venture company established in September 1989 for the purpose of R&D and marketing of drugs. Under the leadership of the CEO, also a medical doctor, the company is developing new drugs on the theme “Physician-Oriented New Drug Innovation”, targeting ophthalmologic and dermatologic diseases that previously had no effective therapeutic agent.