Ro5-4864 alone or in combination with PK-11195 reduces brain Aβ levels in non-Tg mice. Brain levels of soluble AβX-40 (A) and AβX-42 (B) from hemibrain homogenates were assessed by ELISA in young-adult non-Tg mice treated for 4 weeks with vehicle, Ro5-4864, PK11195, or Ro5-4864 + PK11195. Data are mean ± SEM. *p < 0.02, compared with GDX + vehicle. ‡p < 0.001, compared with GDX + vehicle.