WEBULL

Eisai (TSE:4523) Following Leqembi Home Dosing Approval Is The Alzheimer’s Upside Already Priced In

Simply Wall St · 2d ago

Eisai (TSE:4523) is back in focus after fresh Alzheimer’s data and a new at-home dosing option for Leqembi. These developments together reshape how investors might think about the company’s neurology franchise.

See our latest analysis for Eisai.

Eisai’s latest Alzheimer’s updates arrive alongside a 12.12% 1 month share price return, though the share price is still down 7.04% year to date, while the 1 year total shareholder return of 16.39% contrasts with weaker 3 and 5 year total shareholder returns.

If Leqembi has your attention and you are curious about other neurology and treatment focused opportunities, it may be worth scanning the broader healthcare AI stock universe via 7 healthcare AI stocks.

That mix of short term strength and longer term weakness in Eisai shares raises a simple issue: are investors finally recognising underlying progress in the Alzheimer’s franchise, or has sentiment just swung too far for the current valuation?

Most Popular Narrative: 70% Undervalued

The most followed narrative argues that Eisai’s fair value of ¥4,482 sits well above the last close at ¥4,450, framing the current price as a sizable discount once expected Alzheimer’s cash flows and discounting assumptions are factored in.

The launch and approval of the home-administered SC-AI formulation for LEQEMBI, with high physician and patient anticipation, promises to unlock substantial incremental demand through enhanced convenience, improved treatment adherence, and reduced burden on healthcare systems, benefiting both topline revenues and margins through operational efficiencies and lower administration costs.

Read the complete narrative.

Analysts behind this fair value rely on a specific path for revenue growth, margin recovery, and future earnings multiples tied to Eisai’s Alzheimer’s franchise. The key question is which assumptions about patient uptake, profitability, and long-run pricing power need to hold for that view to remain plausible.

Result: Fair Value of ¥4,482 (UNDERVALUED)

Have a read of the narrative in full and understand what's behind the forecasts.

However, Eisai still faces meaningful risks, with pressure on Leqembi pricing and heavy dependence on a small group of drugs. Both factors could weigh on the Alzheimer narrative.

Find out about the key risks to this Eisai narrative.

Another View: Eisai’s Valuation Through Earnings Multiples

The DCF work suggests Eisai is trading at a sizeable discount to projected cash flows, yet the P/E tells a different story. At 32.6x earnings versus a fair ratio of 26x and a JP Pharmaceuticals average of 16.6x, the stock looks expensive on earnings. Which signal do you trust more?

See what the numbers say about this price — find out in our valuation breakdown.

TSE:4523 P/E Ratio as at Jul 2026
TSE:4523 P/E Ratio as at Jul 2026

Next Steps

Mixed on Eisai’s story so far? Take a moment to consider both the concerns and the potential benefits, then review the full picture via 2 key rewards and 1 important warning sign

Looking for more investment ideas beyond Eisai?

If Eisai has sharpened your interest in focused research, do not stop here. Broaden your watchlist with a few targeted stock ideas that match your style.

This article by Simply Wall St is general in nature. We provide commentary based on historical data and analyst forecasts only using an unbiased methodology and our articles are not intended to be financial advice. It does not constitute a recommendation to buy or sell any stock, and does not take account of your objectives, or your financial situation. We aim to bring you long-term focused analysis driven by fundamental data. Note that our analysis may not factor in the latest price-sensitive company announcements or qualitative material. Simply Wall St has no position in any stocks mentioned.