Measurement of plasma γ-Toc and γ-CEHC levels
BLOOD
Blood samples were collected in the mornings of E-D1 and E-D3. All samples were kept light-protected, refrigerated during the collection period, and frozen at -80 °C until analysis. After removing blinding, plasma γ-Toc levels were measured using high-performance liquid chromatography (HPLC) at an external contract laboratory (SRL, Tokyo, Japan). Plasma γ-CEHC levels were measured by HPLC using a modified version of the method described by Galli et al. [