Because of the rapid disease onset and not knowing a priori how early, pre‐ or post‐symptomatically, mice would benefit from an increase in full‐length ApoER2, we treated TgCRND8 (AD) mice and non‐transgenic (WT) littermates as early as possible, 1 or 2 days after birth by ICV injection either with a non‐specific control ASO (ASO‐C), which has no cellular target, or with ASO‐21 specific for ApoER2. ASOs were tolerated well, and no adverse effects on the mice were observed. Here, LRP8 is linked to Alzheimer disease.