Merck Stock Jumps But Reddit Traders Are Getting Cold Feet

A giant in the healthcare space, Merck (NYSE:MRK) shares are up 13.5% year-to-date and trading near $119.47, yet retail sentiment on Reddit has slipped from a bullish 63 over the past quarter to a neutral 43 this week. The catalyst is Merck’s February 23 announcement to split its Human Health business into two divisions: one focused on oncology, the other on specialty pharma and infectious diseases. Investors are asking whether this restructuring is a confident pivot or a quiet acknowledgment that the Keytruda era is ending.

Merck’s Reorganization and the Patent Clock

Keytruda, the world’s top-selling drug, accounts for roughly half of Merck’s revenue (49%), and its compound patent expires in December 2028. CEO Robert M. Davis stated on the Q4 earnings call that “we now have line of sight to over $70 billion of potential commercial opportunity by the mid-2030s, $20 billion more than just a year ago and more than double consensus 2028 peak KEYTRUDA revenue.” RBC Capital initiated coverage with an Outperform rating and a $142 price target, arguing that the company will return to growth in the early 2030s sooner than the market assumes. The consensus 12-month price target sits at $123 with 6 Buy and 6 Hold ratings and no Strong Buy calls, suggesting measured confidence rather than conviction.

What Reddit Is Actually Worried About

The dominant thread driving the sentiment drop comes from r/stocks, where user Pristine_Hurry_4693 laid out the bear case:

Merck faces double threat to lose up to half of its revenue, could a small study with DRTS save it?
by u/Pristine_Hurry_4693 in stocks

As Pristine_Hurry_4693 wrote: “Merck faces a double threat to lose up to half of its revenue, could a small study with DRTS save it?”

The post drew 77 upvotes and a 95% upvote ratio and identifies three concerns:

• Keytruda’s patent cliff in late 2028 threatens roughly half of Merck’s total sales
• AstraZeneca’s Imfinzi could represent the first real competitive mechanism challenge to Keytruda’s dominance beginning in 2028 and beyond
• GARDASIL revenue fell 34% year-over-year in Q4 2025 due to collapsing demand in China

The Pipeline Case That Bulls Are Making

Merck closed roughly $10 billion in acquisitions since 2021, including Verona Pharma and Cidara Therapeutics in 2025. WINREVAIR grew 141% year-over-year to $360 million in Q4. The HIV two-drug regimen combining doravirine and islatrovir carries a PDUFA date of April 28, 2026. Free cash flow surged 172% year-over-year to $6.84 billion. The organizational split, which mirrors the 2021 Organon spin-off playbook, is designed to let each division move faster on pricing, access, and medical strategy. Whether 20 growth drivers can replace one blockbuster is the question investors will be living with through 2028.