SAN DIEGO, Dec. 4, 2017 /PRNewswire/ -- Tioga Pharmaceuticals, Inc. announced today that its selective oral kappa opioid receptor agonist, asimadoline, significantly reduced nighttime itching and improved disease-related quality of life in a randomized, placebo-controlled, double blind clinical trial (RCT) of subjects with atopic dermatitis (AD).
This proof-of-concept study was performed at 25 sites across the U.S. After a one-week, placebo run-in period, subjects with moderate to severe pruritus and an established diagnosis of atopic dermatitis for at least 6 months, were randomly assigned to oral asimadoline, 2.5 mg twice daily, or identical placebo. The four-week double-blind treatment period was followed by a four-week open-label period. In both periods, subjects could increase the dosage of asimadoline from 5mg to 10 mg/day after meeting standardized criteria.
A total of 221 subjects, aged 18 to 82 years, were dosed and completed the RCT. All data analyses performed were pre-planned and specified in the Statistical Analysis Plan. The primary endpoint of safety was met, with no drug-related serious adverse events, and an excellent overall safety profile for asimadoline. Treatment-emergent adverse events, typically mild, were similar in drug and placebo groups. Safety data were reviewed on an ongoing basis by an independent Safety Review Committee. Among secondary endpoints, efficacy, measured by visual analogue (VAS) scores, recorded in electronic diaries, were significantly improved for nighttime VAS in asimadoline-treated subjects compared with placebo (p=.048). Supporting these findings were results from Skindex-10 disease domain questions, measuring the degree to which subjects are bothered by recurrent itching and their skin appearance from scratching. Asimadoline-treated subjects improved significantly compared with controls (p=.023).
"We are extremely pleased by the impact of asimadoline on nighttime itching, typically the hardest symptom to treat, and one strongly associated with poorer general health. We are especially encouraged that there were no 'hangover' effects such as daytime somnolence associated with this improvement in itching. Our principal investigators also observed a significant reduction in redness and scratch marks, as measured by the Eczema Area and Severity Index (EASI), among asimadoline-treated subjects with severe pruritus, providing objective confirmation of benefit. We look forward to asimadoline's development, particularly for the control of nighttime itching and scratching in AD and other pruritic conditions," commented Eric Simpson, MD, Professor of Dermatology, Oregon Health and Sciences University and a lead investigator in the study.
About Atopic Dermatitis:
Atopic Dermatitis (AD) is a chronic inflammatory skin disease that has been increasing in prevalence over the past 30 years. AD is associated with reduced cutaneous immune responses, defective skin barrier function and increased susceptibility to skin infections. Subjects with AD are especially susceptible to skin colonization and infections, scratching increases risk of infection by further compromising the skin barrier to microbes. Skin infections often result in exacerbations of AD. Pruritus is one of the most disabling and stigmatizing features of AD, and adequate treatment represents a large unmet need.
Asimadoline is a proprietary new chemical entity small molecule, originally discovered by Merck KGaA of Darmstadt, Germany. Tioga Pharmaceuticals Inc. purchased asimadoline from Merck and acquired by assignment all worldwide rights. Asimadoline is an investigational drug that is not currently approved for use in any indication.
Asimadoline is an orally active, selective and potent kappa-opioid receptor agonist with approximately 500-fold greater affinity for human kappa, as compared with either delta- or mu-opioid receptors. Asimadoline has been evaluated in 30 clinical studies across the U.S., Europe, and Japan in over 2,000 patients with an excellent safety profile. Kappa-opioid receptors mediate the sensation of itch in animals and humans and kappa‑opioid agonists such as asimadoline have been shown to reduce scratching in animal models.
About Tioga (http://www.tiogapharma.com)
Tioga Pharmaceuticals, Inc. is a privately-held pharmaceutical company headquartered in San Diego, CA. Tioga is funded by Forward Ventures, New Leaf Venture Partners, BB Biotech Ventures, Genesys Capital, and Thomas, McNerney & Partners.
SOURCE Tioga Pharmaceuticals, Inc.