Merck (MRK) moved after first quarter results topped expectations, with strength in Keytruda, animal health, and new launches such as WINREVAIR and IDVYNSO supporting a higher 2026 revenue and earnings outlook.

The Q1 beat and raised 2026 guidance helped lift sentiment, with a 1 day share price return of 2.73% and a year to date share price return of 5.36%. The 1 year total shareholder return of 39.74% points to stronger longer term momentum than the more recent 30 day share price pullback of 7.21%.

If you are looking beyond large pharma and want to see where AI is reshaping healthcare, now is a good time to scan 33 healthcare AI stocks

With Merck shares still below analyst targets and trading at a sizeable modeled intrinsic discount, the key question is simple: is the recent pullback an entry point, or is the market already baking in years of future growth?

Most Popular Narrative: 30% Undervalued

Merck's narrative fair value of $112.55 sits just above the last close at $112.16, so the margin for error in this view is tight.

Merck & Co. presents a compelling long-term investment case, underpinned by its innovative capacity and strong market position. The current valuation, considering both quantitative metrics and qualitative factors, suggests an attractive entry point for investors willing to weather near-term volatility.

However, the looming Keytruda patent expiration necessitates close monitoring of pipeline developments and competitive dynamics. Investors should consider a balanced approach, such as capitalizing on potential short-term technical opportunities while maintaining a long-term perspective on Merck's ability to leverage its R&D strengths and global presence to navigate upcoming challenges.

Curious how this narrative gets to a higher fair value than the market price using modest revenue growth, sizable margins, and a premium earnings multiple assumption.

Result: Fair Value of $112.55 (UNDERVALUED)

However, this narrative could be knocked off course if Keytruda faces quicker than expected erosion around patent expiry, or if regulatory setbacks slow new drug approvals.

Another View: Earnings Multiple Sends a Different Signal

While the narrative fair value suggests Merck is undervalued, the P/E tells a tougher story. At 31x earnings versus 23.9x for peers and 17x for the broader US pharmaceuticals group, the stock is priced richer than many rivals, even though the fair ratio sits close by at 32.2x. Is that premium a comfort, or is it a margin of error you are not being paid for?

Next Steps

If this mix of optimism and concern feels familiar, that is the point. Strong stories usually include both. Take a moment to weigh the data on your own terms, then look at the 2 key rewards and 4 important warning signs

Looking for more investment ideas?

If Merck has sharpened your focus, do not stop here. Your next strong idea could be waiting in plain sight with the right filters and a few minutes of curiosity.

• Target quality at a discount by scanning 51 high quality undervalued stocks to find companies that pair solid fundamentals with prices that may not fully reflect their strengths.
• Prioritise resilience and stability by reviewing 70 resilient stocks with low risk scores built around companies with relatively lower risk scores.
• Spot underfollowed potential by checking screener containing 25 high quality undiscovered gems that combine strong financials with less market attention.

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.