GSK announced that Dermavant Sciences, a subsidiary of Roivant Sciences, has agreed to purchase the rights to tapinarof, an investigational therapeutic aryl hydrocarbon receptor modulating agent (TAMA) for the treatment of psoriasis and atopic dermatitis and back-up programmes for a total consideration of £250 million, including an initial payment of £150 million and a potential future milestone payment of £100 million.
The transaction is anticipated to complete during the second half of 2018, subject to necessary approvals, anti-trust and regulatory clearances. As part of the transaction, GSK, Roivant and Dermavant will enter into agreements for supply of the investigational medicine for the phase III programme and commercial supply. At closing of the transaction, Dermavant will acquire all global rights to tapinarof, except in China. Dermavant will acquire global rights to the preclinical topical back-up programme to tapinarof and will assume responsibility for all development milestones owed to third parties.
John Lepore, MD, Senior Vice President, R&D pipeline, GSK, said: “We have taken a strategic decision to divest or partner medicines in our R&D portfolio that are a better fit for other companies allowing us to concentrate our resources on other promising assets. Tapinarof has the potential to be a first-in-class therapy and a convenient, once-daily topical agent that postpones or potentially eliminates the need for systemic treatment in two of the most common dermatological conditions, psoriasis and atopic dermatitis. We are confident that Dermavant is well positioned to progress rapidly with the tapinarof development programme into phase III and registration.”
Mayukh Sukhatme, MD, President of Roivant Pharma, said: “We are excited to partner with GSK as we pursue the rapid initiation of phase III development for tapinarof. It is the ideal drug to complement Dermavant’s existing pipeline of innovative therapies.”
Jackie Fouse, PhD, Executive Chair of Dermavant Sciences, said: “Tapinarof is an investigational therapy that has the potential to provide an important treatment option for psoriasis and atopic dermatitis, conditions affecting millions of patients around the world. This will be the cornerstone of Dermavant’s pipeline, and we are grateful for the opportunity to advance its development.”
Tapinarof Clinical Development Programme
Tapinarof has been evaluated as a topical therapy in multiple phase I and phase II studies involving over 800 human subjects.
In a double-blind, placebo-controlled, global phase IIb dose-ranging study that enrolled 227 adults with plaque psoriasis, tapinarof demonstrated clinically meaningful, dose-dependent improvements over vehicle on the primary endpoint of the study, the proportion of treated patients who achieved Physician Global Assessment (PGA) scores of clear or almost clear (0 or 1) after 12 weeks of treatment with a minimum of 2-grade improvement in 5-point PGA score from baseline.
56% of patients in the tapinarof 1% once-daily group, and 46% of patients in the tapinarof 0.5% once-daily group, achieved 75% or greater improvement in Psoriasis Area and Severity Index scores (PASI 75) after 12 weeks of treatment, compared to 5% in the placebo once-daily group. The most frequently reported adverse events were folliculitis, contact dermatitis and headache.
In a separate double-blind, placebo-controlled global phase IIb dose-ranging study that enrolled 247 patients with atopic dermatitis, tapinarof demonstrated clinically meaningful, dose-dependent improvements over vehicle on the primary endpoint of the study, the proportion of patients with Investigator Global Assessment (IGA) scores of clear or almost clear (0 or 1) after 12 weeks of treatment with a minimum of 2-grade improvement in 5-point IGA score from baseline. Tapinarof was generally well tolerated in both studies. The most frequently reported adverse events were folliculitis, contact dermatitis and the common cold. Efficacy assessments in both studies were made on a modified intent-to-treat population.