For OTX015 plasma and tissue concentrations, samples were collected 4 h after the last OTX015 treatment. Mice were sacrificed and blood was collected from the heart in heparinized tubes, separated immediately by centrifugation (4000 rpm, 15 min, 4°C), and stored at −80°C. Plasma concentrations were measured using a validated Ultra Performance Liquid Chromatography with tandem Mass Spectrometry method, as previously described . For tissue measurements, frozen samples were weighed and then homogenized in 1 mL of water, and a 50 μL sample was prepared using the same extraction method as that used for plasma samples.