IC50: 75 μM (RXRα)
Tarenflurbil ((R)-Flurbiprofen) can significantly reduce Aβ secretion, but at the same time, increases the level of intracellular Aβ. The binding between [ 3 H]9-cis-RA and RXRα is competitively inhibited by both unlabeled (R)-Flurbiprofen and 9-cis-RA. (R)-Flurbiprofen can interfere with the interaction between RXRα and 9-cis-retinoid acid (9-cis-RA), and that 9-cis-RA decreases Tarenflurbil ((R)-Flurbiprofen)’s reduction of Aβ secretion. Tarenflurbil ((R)-Flurbiprofen) treatment significantly increases the levels of intracellular Aβ species. The well characterized, nonsteroidal anti-inflammatory drug (nonsteroidal anti-inflammatory drug), Tarenflurbil ((R)-Flurbiprofen) affects only Aβ and not Notch β formation, indicating that second generation GSMs and nonsteroidal anti-inflammatory drug-based GSMs have different modes of action regarding Notch processing.
Effects of the early and late onset of treatment with Tarenflurbil ((R)-Flurbiprofen) are assessed in C57BL6/J mice that develop a non-remitting form of the disease, and in SJL mice that develop a relapsing-remitting (RR)-EAE. Tarenflurbil ((R)-Flurbiprofen) completely prevents the development of clinical EAE scores in C57BL6/J mice when the treatment is started within 3 days after immunization. This regimen is referred to as preventive treatment. The effect is dose-dependent, and the minimum daily dose for complete prevention is 5 mg/kg/day. Effects of Tarenflurbil ((R)-Flurbiprofen) are comparable to those of Fingolimod (FTY720, 0.5 mg/kg/day), which is used as the positive control. Tarenflurbil ((R)-Flurbiprofen) also significantly reduces clinical EAE scores in C57BL6/J mice when treatment is started shortly before onset of clinical manifestations, referred to as semi-therapeutic (10 mg/kg/day) and reduces clinical scores when the treatment is initiated after full development of the disease on day 13 (5 mg/g/day).