Alector (NASDAQ:ALEC) shares dropped more than 4% pre-market today after Goldman Sachs analysts started coverage on the company with a Sell rating and a price target of $4.00.

The analysts expressed significant concerns about the company's lead clinical-stage programs, latozinemab for Frontotemporal Dementia and AL002 for Alzheimer's disease. While acknowledging the mechanistic rationale behind both agents, there is limited data supporting their translation into clinical benefits.

Both latozinemab and AL002 enhance the activity of specific targets known to be reduced in patients with FTD and AD, but it's uncertain whether increasing these levels directly leads to clinical improvement.

Furthermore, the analysts noted that data from both programs won't be reported until late 2024 or 2025, creating a substantial catalyst gap before potentially de-risking results.