FDA Breakthrough Therapy Designation for Topical Vitamin A Derivatives to Treat Inherited Skin Diseases

Recently, Timber Pharmaceuticals announced that the U.S. Food and Drug Administration (FDA) has granted breakthrough therapy designation to its investigational topical isotretinoin drug TMB-001 for the treatment of congenital ichthyosis (CI).

CI is a rare inherited keratotic disorder that causes dry, thickened, and scaling skin. Moderate to severe CI subtypes include X-linked recessive ichthyosis (XRI) and lamellar ichthyosis in autosomal recessive congenital ichthyosis (ARCI-LI). In patients with XRI and ARCI-LI, it usually presents as extensive black scales on the skin all over the body.

TMB-001 is a topical isotretinoin drug developed through Timber Pharmaceuticals' proprietary delivery system for the treatment of moderate to severe CI. Isotretinoin is a vitamin A derivative.

In the Phase 2b CONTROL study evaluating TMB-001 in the treatment of moderate to severe CI, TMB-001 demonstrated clinically meaningful efficacy and a favorable safety profile. An analysis of studies presented at the American Academy of Dermatology (AAD) 2022 Annual Meeting showed that patients experienced treatment success with TMB-001 regardless of the subtype of CI.

Timber Pharmaceuticals has initiated a pivotal Phase 3 clinical trial to further study the efficacy and safety of TMB-001 in patients with CI, and is expected to dose the first patients in June 2022. This clinical trial will evaluate the efficacy, pharmacokinetics and safety of TMB-001 0.05% in 142 patients with moderate to severe CI.

"This is an important time for people with CI, their families and caregivers, as well as clinicians and researchers who have spent years finding new treatments for this debilitating disease." Timber Pharmaceuticals Chairman and Chief Executive Officer John Koconis said, "I am proud of the team's ability to demonstrate the potential of TMB-001 in a Phase 2b study, and we are rapidly advancing into a pivotal Phase 3 clinical trial."