in vitro: PF-8380 is a specific autotaxin inhibitor with an IC(50) of 2.8 nM in isolated enzyme assay and 101 nM in human whole blood. PF-8380 has adequate oral bioavailability and exposures required for in vivo testing of autotaxin inhibition.

in vivo: PF-8380, dosed orally at 30 mg/kg, provided >95% reduction in both plasma and air pouch LPA within 3 h, indicating autotaxin is a major source of LPA during inflammation. At 30 mg/kg PF-8380 reduced inflammatory hyperalgesia with the same efficacy as 30 mg/kg naproxen. Inhibition of plasma autotaxin activity correlated with inhibition of autotaxin at the site of inflammation and in ex vivo whole blood. Pre-treatment of GL261 and U87-MG cells with 1?μM PF-8380 followed by 4?Gy irradiation resulted in decreased clonogenic survival, decreased migration (33% in GL261; P=0.002 and 17.9% in U87-MG; P=0.012), decreased invasion (35.6% in GL261; P=0.0037 and 31.8% in U87-MG; P=0.002), and attenuated radiation-induced Akt phosphorylation.