Alan Mendelsohn, MD, Chief Medical Officer at Timber Pharmaceuticals, gives an update on their congenital ichthyosis clinical trial.

Congenital ichthyosis is a rare genetic skin disorder characterized by dry, thickened, and scaling skin. Individuals with this condition may experience limited range in motion, chronic itching, an inability to sweat, and increased risk of infections. Currently, there is no approved targeted therapy for congenital ichthyosis. Symptom management for the condition is most often achieved with topical treatments (e.g., emollients, keratolytics, frequent baths, pumice stones) aimed at reducing the scaling and/or improving skin lubrication.

As Dr. Mendelsohn explains, for many years it has been known that retinoid therapy could play a crucial role in the treatment of congenital ichthyosis. The issue with retinoid therapies, particularly oral options, is their high toxicity when taken long-term. Timber Pharmaceuticals, with this in mind, developed a retinoid therapy that could be applied topically to reduce toxicity and hopefully allow congenital ichthyosis patients to use the therapy long-term.
The phase 2b CONTROL study was a randomized, double-blind, vehicle-controlled study designed to assess the efficacy and safety of two concentrations of TMB-001 (0.05% and 0.1% isotretinoin) for the treatment of two distinct subtypes of moderate-to-severe congenital ichthyosis (X-linked recessive and lamellar ichthyosis) in patients nine years old or older. Subjects applied TMB-001 twice daily for 12 weeks. The primary endpoint was the reduction of targeted ichthyosis severity, determined by a ≥50% reduction in the validated Visual Index for Ichthyosis Severity (VIIS) scaling score. Secondary endpoints included reduction in overall ichthyosis severity, as measured by a two-point improvement using the Investigator Global Assessment (IGA) scale. Topline results of this study showed reduction in targeted and overall severity of ichthyosis in patients in both treatment groups as measured by the VIIS scaling score and the IGA scale.

As Dr. Mendelsohn mentions, Timber Pharmaceuticals is planning for an end-of-Phase 2 meeting with the FDA in the beginning of 2022 and expects to start the Phase 3 study of TMB-001 in Q2 2022.

To learn more about congenital ichthyosis and other rare skin disorders, visit https://checkrare.com/diseases/skin-conditions/