4SC AG has announced that resminostat, also known as Kinselby, has received Orphan Drug Designation (ODD) from both the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA) for the treatment of cutaneous T-cell lymphoma (CTCL). These designations offer significant benefits, including market exclusivity, as the company advances towards regulatory approval.
Orphan Drug Designation Benefits
The FDA's ODD for resminostat grants 4SC seven years of market exclusivity in the United States. Similarly, the EMA's ODD provides ten years of market exclusivity within the European Union. These designations aim to incentivize the development of treatments for rare diseases affecting limited patient populations.
Jason Loveridge, Ph.D., CEO of 4SC, stated, "Receiving orphan drug designation for resminostat provides us with a number of important benefits, most crucially 7 years’ market exclusivity in the US, a key foundation of our efforts to commercialise Kinselby. We are currently preparing a marketing authorisation application for Kinselby in the EU, which remains on track for submission in Q1 2024."
Resminostat's Mechanism and Clinical Development
Resminostat is an orally administered inhibitor targeting class I, IIb, and IV histone deacetylases (HDAC). It has demonstrated the ability to inhibit tumor growth and proliferation, induce tumor regression, and enhance the body's immune response to cancer. The drug is currently under investigation in the pivotal RESMAIN study for CTCL maintenance treatment, both in Europe (by 4SC) and in Japan (by Yakult Honsha).
The RESMAIN study, a Phase III trial, involved 201 patients with advanced-stage CTCL across 50 clinical centers in Europe and Japan. Patients who had achieved disease control with systemic therapy were randomized to receive either resminostat or placebo. The primary endpoint was progression-free survival, which resminostat successfully met, as published in May 2023.
Cutaneous T-Cell Lymphoma (CTCL) and Unmet Needs
CTCL is a rare malignancy arising from the transformation of T-cells, primarily affecting the skin. Approximately 5,000 new cases are diagnosed in Europe annually. While current treatments can induce responses, these are often short-lived, highlighting the need for more durable therapeutic options.
Resminostat is being evaluated as a maintenance therapy to prolong periods of disease stability and improve patients' quality of life. This approach addresses a critical unmet need in advanced-stage CTCL, where patients experience painful skin lesions and impaired quality of life, with limited options for long-lasting disease control.
