4SC AG, a German biotech company, announced that the European Medicines Agency (EMA) is continuing its review of the Marketing Authorisation Application (MAA) for resminostat (Kinselby) as a treatment for advanced-stage cutaneous T-cell lymphoma (CTCL). The company submitted its responses to the EMA's Day-120 List of Questions in December 2024, following the initial MAA filing in March 2024. Marketing authorization approval is anticipated around mid-2025, subject to the EMA's decision.
Resminostat received Orphan Drug Designation from the EMA in 2023 and from SwissMedic in September 2024.
Clinical Efficacy of Resminostat in CTCL
The MAA is supported by data from the pivotal RESMAIN study, a randomized, placebo-controlled trial involving 201 patients with advanced CTCL across 11 European countries and Japan. The study evaluated resminostat as a maintenance therapy in patients who had achieved disease control with prior systemic treatment.
The RESMAIN study demonstrated a statistically significant improvement in progression-free survival (PFS) with resminostat compared to placebo (median PFS: 8.3 months versus 4.2 months, representing a 97.6% improvement). Additionally, the median time to next treatment (TTNT) was more than doubled with resminostat (8.8 months versus 4.2 months with placebo). The median "total" PFS was 24.3 months in the resminostat group, compared to 14.9 months in the placebo group. The side effects of resminostat were mainly mild to moderate, manageable, and reversible.
The Need for New CTCL Therapies
CTCL is a rare, incurable form of non-Hodgkin lymphoma affecting approximately 5,000 new patients in Europe each year. The disease involves malignant transformation of T-cells, primarily affecting the skin and potentially spreading to lymph nodes, blood, and visceral organs. Current treatment options for advanced CTCL are limited, and while initial responses to therapy may occur, they are often short-lived.
Mechanism of Action
Resminostat is an orally available histone deacetylase (HDAC) inhibitor of classes I, IIb, and IV. It has demonstrated the ability to inhibit tumor growth and proliferation, induce tumor regression, and enhance the body's immune response to cancer.
Management Perspective
"This filing marks a significant step forward for resminostat (Kinselby) as we progress ever closer to marketing authorisation approval, which is expected in mid-2025," said Jason Loveridge, Ph.D., CEO of 4SC. "We remain committed to bringing this much needed treatment to patients as soon as possible, and preparations for market launch are ongoing, as well as actively engaging with potential partners interested in commercializing the drug."
