Cutaneous T-cell lymphoma (CTCL) is a rare form of blood cancer that shows up first in the skin. A key unmet medical need for patients in early-stages of CTCL is efficacy on cancerous skin lesions and the symptom of significant itching.
CTCL affects around 20,000 people in each of the US and Europe and approximately 75 percent of patients are in early stages (1).
In its early stages, the disease is confined to the skin and is not immediately life threatening. Patients do however experience a reduction in quality of life due to disfiguring lesions and disease symptoms, mainly significant itching.
Patients also suffer an increased risk of infections as the protective skin barrier is no longer intact. Existing treatments do not sufficiently address the patient need. Thus, patients are in need of an efficacious but also highly tolerable treatment, since the early stages of disease may last for many years.
In the US alone, 15,000 patients with early stage CTCL represents a total market potential of USD 900 million.
Medivir is developing remetinostat as a topical application for use in early stage CTCL. Remetinostat is a histone deacetylase (HDAC) inhibitor. HDAC inhibitors are approved for treatment of CTCL in late-stage patients but are not recommended for early-stage patients due to their significant side effects. The unique design of remetinostat enables topical application, making it active only in the skin. As soon as it reaches the blood stream, it is degraded, avoiding the side effects associated with other HDAC inhibitors.
In the recently completed phase II study, remetinostat demonstrated efficacy on skin lesions, reduction of itching and high tolerability in patients with early-stage CTCL. This positive top-line data showed that patients that were given the highest dose in the study (remetinostat gel 1% twice daily) had the highest proportion of confirmed responses (40 percent, 8 patients out of 20). In addition, 80 percent of the patients in this dose group who had clinically significant itching at baseline experienced a meaningful reduction in the severity of their itching. Remetinostat was well-tolerated and without signs of systemic adverse effects in the study.
Based on the promising phase II results, Medivir has initiated discussions with the US FDA and is preparing for a phase III study in CTCL to be initiated in 2018. Remetinostat has been granted Orphan Drug Designation (ODD) in the US. Medivir also intends to investigate the possibility to use remetinostat in other cancers found in the skin.