– VU0652957 (VU2957, Valiglurax) is a potent, selective mGlu4 positive allosteric modulator (PAM) with EC50 of 64.6 nM in calcium mobilization human mGlu4/Gqi5 assays; showes excellent pharmacokinetics across species (low CLps, %F > 35%), an acceptable CYP profile (>30 uM vs. 3A4, 2D6 and 2C9, 12.5 uM vs. 2C19 and 1.5 uM vs. 1A2), no CYP induction or timedependent inhibition and excellent metabolite coverage across species; also shows attractive predicted human PK parameters (CLps 5-9 mL/min/kg, Vds 1-2 L/kg and t1/2 2-4 hours).