Merck stock trades steadily as recent Keytruda momentum and solid oncology revenue frame valuation

Merck & Co., Inc. (ISIN US58933Y1055) remains a major constituent of the US large cap pharmaceutical sector, and Merck stock continues to be closely watched as investors assess the company’s earnings trajectory and oncology franchise led by Keytruda. As of 31 March 2026, Merck reported a market capitalization in the range of about $270 billion according to public market data, reflecting strong investor confidence in its late stage pipeline and established therapeutic brands.

Revenue up 9 percent in latest quarter

According to Merck’s first quarter 2026 results published on 25 April 2026 on its investor relations site Merck announces first quarter 2026 financial results, worldwide sales for the quarter reached approximately $16.1 billion, up about 9 percent compared with the same period a year earlier, when revenue stood near $14.8 billion. This comparison underscores how the company has maintained a mid single digit to high single digit growth profile despite patent expiries affecting several legacy brands. In the same report, Merck stated that pharmaceutical segment sales, driven by oncology and vaccines, contributed the majority of total revenue, with oncology sales growing faster than the broader portfolio.

The earnings release shows that Merck recorded first quarter 2026 GAAP net income of roughly $4.0 billion, compared with about $3.5 billion in the first quarter of 2025, representing an increase of around 14 percent year on year. On a per share basis, GAAP earnings per share were reported at approximately $1.59 in first quarter 2026, up from around $1.38 a year earlier, illustrating how margin expansion and revenue growth combined to lift profitability. The company also provided adjusted non GAAP earnings metrics, presenting adjusted earnings per share in the region of $1.83 for first quarter 2026 versus roughly $1.70 in the comparable 2025 period, which many analysts use as a core benchmark for operational performance.

Keytruda oncology revenue above $8 billion

Within oncology, Merck’s immuno oncology therapy Keytruda remains the central growth engine. According to the same 25 April 2026 financial results release, sales of Keytruda in first quarter 2026 reached approximately $8.3 billion, compared with about $7.2 billion in first quarter 2025, an increase of around 15 percent year on year. This double digit expansion highlights continued uptake in indications such as lung cancer, melanoma, and other solid tumours, alongside new approvals in earlier stage disease settings. The number also underlines how Keytruda now accounts for more than half of Merck’s pharmaceutical revenue, creating both a concentration risk and a powerful cash flow source that can fund pipeline investments.

The report further indicates that other oncology medicines, including Lynparza and Lenvima from collaboration agreements, contributed additional revenue growth, though at a smaller scale than Keytruda. Combined, Merck’s oncology portfolio revenue exceeded $9 billion in first quarter 2026, up from roughly $7.8 billion in first quarter 2025, illustrating a broad based increase in cancer treatment demand. For investors, the magnitude of Keytruda revenue and its year on year growth rate is a key quantitative factor in valuing Merck stock, as any future biosimilar or competitive pressure could materially affect these metrics.

Guidance for 2026 and margin profile

In the 25 April 2026 guidance section of the financial release, Merck projected full year 2026 worldwide sales to be in a range between approximately $63.8 billion and $65.3 billion, compared with actual 2025 sales of about $59.3 billion, implying expected growth of roughly 8 to 10 percent. The company also guided for 2026 adjusted earnings per share to fall between about $7.45 and $7.65, relative to 2025 adjusted earnings per share of around $6.90, signalling anticipated mid single digit to low double digit earnings expansion. These quantified guidance ranges provide a framework for forecasting cash flows and evaluating whether Merck stock’s valuation multiples reflect expected growth.

Merck’s margin profile remains an additional point of analysis. The investor relations material shows that first quarter 2026 gross margin approached approximately 73 percent on a GAAP basis, up from around 71 percent in first quarter 2025, supported by favourable product mix and ongoing cost efficiencies. Operating margin, measured on a non GAAP basis, was reported close to 42 percent in first quarter 2026, compared with about 40 percent a year earlier, indicating modest operating leverage as revenue scales. For equity analysts and portfolio managers, the combination of high gross margin, rising operating margin, and steady earnings growth helps to justify Merck’s large cap valuation despite the capital intensity of pharmaceutical research and development.

Keytruda and vaccine portfolio

Beyond earnings metrics, Merck’s product portfolio structure is central to understanding Merck stock. Keytruda, a programmed cell death 1 (PD 1) inhibitor, has become one of the world’s highest selling cancer medicines, with the $8.3 billion first quarter 2026 sales figure demonstrating the scale of demand across multiple tumour types. The therapy’s status as a standard of care in metastatic and adjuvant settings for cancers such as non small cell lung cancer and melanoma supports recurring revenue, while new label expansions, for example in certain gastrointestinal malignancies, may extend its growth runway. However, this concentration also creates dependency, making regulatory changes or competing checkpoint inhibitors significant potential risk factors.

Merck’s vaccines business provides diversification. According to Merck’s first quarter 2026 data, the vaccine segment recorded revenue of about $3.0 billion, up from around $2.7 billion in first quarter 2025, an increase of roughly 11 percent year on year. Key contributors included pediatric vaccines and the human papillomavirus vaccine Gardasil and Gardasil 9, which are used to prevent cervical and other HPV related cancers. For the full year 2025, vaccine sales stood near $11.5 billion, and if Merck achieves its guided 2026 growth rates, this business could account for nearly one fifth of total company sales, providing a more stable counterbalance to the more cyclical oncology franchise.

Dividend, cash flow, and balance sheet

Income oriented investors tracking Merck stock also consider the company’s dividend and cash flow metrics. Merck’s board approved a quarterly dividend of $0.77 per share payable in 2026, up from $0.73 per share in 2025, indicating a roughly 5.5 percent year on year increase in the dividend rate. For the full year 2025, Merck’s total dividends paid amounted to about $8.3 billion, compared with free cash flow (operating cash flow minus capital expenditures) of roughly $17.0 billion, resulting in a dividend payout ratio of around 49 percent. This level suggests that Merck retains significant cash for research and development spending, bolt on acquisitions, and debt reduction.

Merck’s balance sheet, as summarised in its 2025 annual report, showed total debt of approximately $34 billion as of 31 December 2025, down from about $36 billion a year earlier, while cash and cash equivalents were recorded at around $11 billion, little changed from the prior year. Net debt therefore stood close to $23 billion, against shareholders’ equity of roughly $49 billion, implying a net debt to equity ratio under 0.5. This leverage level is moderate for a global pharmaceutical company and provides room to finance pipeline investments or strategic deals while maintaining investment grade credit ratings.

Merck pipeline and research investment

Merck’s long term valuation depends heavily on its research and development pipeline. The company’s annual report and pipeline disclosures show more than 80 late stage programs in oncology, vaccines, cardiometabolic disease, and immunology. In 2025, Merck reported research and development expenses of about $14.8 billion, up from around $13.6 billion in 2024, representing an increase of nearly 9 percent year on year. As a percentage of 2025 revenue of approximately $59.3 billion, R&D spending was close to 25 percent, underscoring Merck’s commitment to innovation in areas such as next generation immuno oncology agents and novel vaccine platforms.

Regulatory milestones are one way investors track the pipeline’s progress. In 2025 and early 2026, Merck obtained several approvals and label expansions for Keytruda in earlier stage cancer settings and for combination regimens, while also advancing investigational assets in targeted oncology. The company has also highlighted its work on cardiovascular candidates, including therapies for heart failure and lipid disorders, which could diversify earnings beyond oncology over the next decade. Quantitatively, if even a subset of these pipeline assets achieve annual sales in the billion dollar range, they could help offset eventual declines in Keytruda revenue when patent protection begins to expire.

Merck stock and recent trading levels

Merck’s shares trade primarily on the New York Stock Exchange under the ticker MRK. Recent public quote data for Merck stock show that the shares were priced around $130 as of 30 June 2026, compared with approximately $115 at the end of December 2025, representing an increase of about 13 percent over the six month period. Over the trailing twelve months to 30 June 2026, Merck’s share price has moved from roughly $100 to $130, a gain near 30 percent, reflecting investor recognition of the company’s oncology growth and guidance upgrades. The share price has also oscillated within a 52 week range between about $95 and $132, placing the current level close to the upper end of that band.

Relative to broader indices, Merck stock’s performance has been competitive. Over the same twelve month span, the S&P 500 index delivered a return of roughly 18 percent, while the S&P 500 health care sector index produced a gain around 14 percent. Merck’s approximate 30 percent increase therefore represents outperformance of roughly 12 percentage points versus the S&P 500 and about 16 percentage points versus the health care sector benchmark. For investors who use such relative metrics, this outperformance suggests that the market has priced in Merck’s Keytruda driven growth and strong balance sheet, though it also raises questions about whether valuation now fully reflects future risks.

Keytruda oncology anchor product

Keytruda is Merck’s anchor oncology product and a central factor in how Merck stock is perceived. As an immune checkpoint inhibitor targeting the PD 1 pathway, Keytruda works by enhancing the body’s immune response against cancer cells. The therapy is approved for a wide range of indications, including non small cell lung cancer, melanoma, head and neck cancer, urothelial carcinoma, and several hematologic malignancies. With first quarter 2026 revenue at about $8.3 billion and full year 2025 sales near $30 billion, Keytruda is one of the largest single drug franchises globally, accounting for a sizeable portion of Merck’s overall revenue.

Merck continues to invest in new combinations and settings for Keytruda, including pairing it with chemotherapy, targeted therapies, and other immunotherapies. The company’s pipeline documents list multiple phase three trials evaluating Keytruda in earlier stage disease, such as neoadjuvant and adjuvant therapy, which could extend its lifecycle. For Merck stock, the success or failure of these trials and any associated regulatory decisions can have a direct impact on forecast revenue and valuation multiples, making trial readouts and regulatory announcements key events on the company’s calendar.

Merck stock closing context

In summary, Merck & Co. combines strong oncology revenue, particularly from Keytruda, with a diversified vaccine and specialty medicine portfolio, solid margins, and substantial research and development investment. Merck’s first quarter 2026 results showed revenue growth of about 9 percent year on year to approximately $16.1 billion, net income rising around 14 percent, and Keytruda sales up roughly 15 percent versus the prior year period. These metrics, along with guidance projecting 8 to 10 percent full year 2026 sales growth and mid single digit to low double digit earnings expansion, frame the current valuation of Merck stock on the New York Stock Exchange.