Phase 2 Dose-finding IMU-838 for Ulcerative Colitis

The investigational medicinal product (IMP) IMU-838 (vidofludimus calcium) is a new compound that selectively inhibits the human enzyme dihydroorotate dehydrogenase (DHODH). Dihydroorotate dehydrogenase plays a major role in the de-novo pyrimidine synthesis and is specifically expressed at high levels in proliferating or activated lymphocytes. Resting lymphocytes satisfy their pyrimidine requirements through a DHODH-independent salvage pathway. Thus, IMU-838-mediated DHODH inhibition selectively affects activated, rapidly proliferating lymphocytes. The metabolic stress secondary to DHODH inhibition leads to a reduction of pro-inflammatory cytokine release including interleukin (IL)-17 (IL-17A and IL-17F) and interferon gamma (IFNγ), and to an increased apoptosis in activated lymphocytes.

This is a phase 2, multicenter, randomized, double-blind, and placebo-controlled trial in patients with moderate-to-severe UC with an option for open-label treatment extension. The study comprises a blinded induction phase to establish the optimal dose of IMU-838 to induce response and remission, a blinded maintenance phase to evaluate the potential of IMU-838 to maintain remission until Week 50, and an open-label treatment extension arm for all patients who discontinue the blinded phase as scheduled or prematurely, subject to certain restrictions. A subset of patients will undergo a pharmacokinetic (PK) period at the start of the open-label period to establish a full single-dose PK profile.