IT-901 is an orally active and potent NF-κB subunit c-Rel inhibitor with IC50 values for NF-κB and c-Rel binding to DNA of 0.1 µM and 3 µM, respectively. IT-901 is a naphthalene thiobarbiturate derivative with antitumor activity and is used for the prevention and treatment of human lymphoma and myeloma.

GCB:4 μ M, NF-κB:0.1 μM, c-Rel:2.9μM

Following 24 hours of treatment with IT-901 at concentrations of 1, 3, and 5 μM, there is a reduction in the proliferation of viable ABC and GCB DLBCL cells[2].
At a concentration of 3 μM and a duration of 24 hours, IT-901 induces a dose-dependent decrease in cell viability. However, at least 60 percent of cells remain viable after 48 hours of treatment with 4 μM IT-901 in all tested cell lines, except HBL1[2].
With a treatment duration of 6 hours and concentrations of 1, 5, and 10 μM, IT-901 leads to a diminished expression of p65 and p50 in both nuclear and cytosolic fractions. Additionally, it reduces the expression of the inhibitory subunit IκBα in both phosphorylated and non-phosphorylated forms in primary CLL cells and cell lines[2].The IC50 of IT-901/GDM-12 is 2.9 μM for c-Rel, while IL-2 secretion is effectively blocked at 5 μM[2].
Concentrations of IT-901 above 10 μM become increasingly toxic and may induce apoptosis in healthy cells[2].
IT-901 demonstrates inhibition of cell growth in both activated B-like (ABC) and germinal center B-like (GCB) cell lines, with IC50 values ranging between 3 μM to 4 μM[2].

Administered intraperitoneally (IP) every other day for 2 weeks at a dose of 24 mg/kg, IT-901 proves to be an effective treatment for acute graft-versus-host disease (GVHD) without compromising its anti-tumor activity[2].
IT-901, given at doses ranging from 12 to 20 mg/kg via IP administration, enhances the pharmacokinetic (PK) profile by increasing both half-life (T1/2) and maximum plasma concentration (Cmax)[2].