This is an exploratory Phase 0 study in participants who previously participated in studies (54861911ALZ2002 \[NCT02260674\], 54861911ALZ2003 \[NCT02569398\], or 54861911ALZ2004 \[NCT02406027\]) with atabecestat. In this study, participants will only have blood drawn. The primary hypotheses for this study is that adverse event of elevated liver enzymes observed in some participants is caused by a T-cell dependent inflammatory response. Participants will be monitored for adverse events and will be called 1 day after the blood draw to assess for any adverse events.
