Merck & Co., Inc. (MRK) Income Statement

Revenue growth has decelerated from the 7-9% range seen in early 2024 to low single digits in 2025-2026, indicating that Keytruda's expansion is offsetting declines elsewhere but not driving acceleration. The 5.1% growth in 2026Q2 is the strongest in recent quarters, but it remains modest and may be influenced by inventory timing or one-time factors. Without updated guidance, the durability of even this modest growth is uncertain, especially as IRA price negotiations on Januvia and the looming Keytruda patent cliff create headwinds.

The gross margin trend shows a slight deterioration from the 77%+ levels of early 2024 to the mid-70s in 2025-2026, likely reflecting product mix shifts and pricing pressure. The 81.9% in 2026Q1 is an outlier that may be due to one-time items or favorable product mix, but the subsequent quarter's 73.5% indicates that such levels are not sustainable. Compared to peers like LLY (83.8%) and JNJ (72.8%), Merck's gross margin is competitive but not best-in-class, and the IRA-driven price cuts on Januvia could further compress margins.

The dramatic swing in operating margin from 43.4% in 2025Q3 to -11.6% in 2026Q1 is not a reflection of operational deterioration but rather a massive, likely one-time R&D charge. This suggests that Merck is making a strategic bet on pipeline development, possibly including acquisitions or milestone payments, which temporarily destroys operating leverage. Investors should monitor whether this elevated R&D intensity is a one-off or a new trend, as it could signal a shift toward a more investment-heavy phase that may pressure near-term profitability.

The R&D line is the primary cost driver and the source of the recent earnings shock, with the 2026Q1 figure of $12.6B being nearly four times the typical quarterly run rate. This suggests a major pipeline investment or a one-time charge, possibly related to an acquisition or a large milestone payment. SG&A has been well-controlled, indicating that management is not overspending on marketing, but the R&D spike raises questions about capital allocation discipline and the expected return on these investments.

This quarter is a departure from the stable, profitable pattern of 2024-2025, and it appears to be driven by a strategic decision to accelerate pipeline investment, possibly in response to the Keytruda patent cliff. The lasting impact is that Merck's near-term earnings power is now clouded by elevated R&D costs, and investors will need to see whether this investment translates into future revenue growth. The lack of updated guidance makes it difficult to assess whether this is a one-time event or the beginning of a new investment cycle.