The ASCEND Study: Evaluating TMB-001 in the Treatment of RXLI or ARCI Ichthyosis

This is a multicenter, randomized, double-blind, vehicle-controlled Phase III study to evaluate the efficacy and safety of TMB-001 0.05% topical ointment in the treatment of CI. Subjects will be selected according to predefined entry criteria. The study treatment duration is 24 weeks and expected to be sufficient to show a treatment effect. Isotretinoin is an approved active pharmacological ingredient with a long history of safe use in humans. However, isotretinoin is a known teratogen with an extremely high risk for severe birth defects if pregnancy occur while taking oral isotretinoin in any amount, even for a short period of time. Therefore oral, systemic isotretinoin requires an iPLEDGE program (iPLEDGE 2012), which is a risk management distribution program mandated by the FDA. To minimize pregnancy risks, women of childbearing potential (WOCBP) will only be enrolled if they agree to use highly effective methods of contraception consistently and correctly and undergo regular pregnancy testing. To minimize bias, subjects will be blinded and randomly assigned to treatment with TMB-001 0.05% or Vehicle, additionally subjects who had previously been treated with TMB 001 will be excluded from this study but can be enrolled in the optional Maximal Use arm (in a subset of preselected centers). The use of a vehicle control group is consistent with FDA's standard for generating valid scientific evidence to definitively support safety and efficacy. The vehicle group accounts for the effects of treatment that do not depend on the test treatment. The study is designed to mitigate safety risks by using an initial 2:1 randomization (active treatment to vehicle), along with frequent clinic visits over the 12-week treatment period. The subsequent 1:1 randomization of eligible TMB-001 0.05% treated subjects to two dosing regimen (QD or BID) allows for assessment of the optimal TMB-001 0.05% maintenance therapy as well as provides additional safety data for 12 weeks. The cross-over of eligible subjects from the vehicle control group will also provide additional safety data. Overall, the study design is considered to be scientifically robust and clinically relevant for evaluating TMB-001 0.05% treatment for the safe and effective treatment of CI.