Merck Q3 2025 Earnings Breakdown: Keytruda Dominance, Vaccine Softness, and Pipeline Diversification

In the third quarter of 2025, Merck reported pharmaceutical segment sales of $15.61 billion, reflecting continued growth in oncology and early momentum from newer cardio-pulmonary assets. With Keytruda's U.S. compound patent due to expire in December 2028, Merck’s earnings profile highlights both the durability of its core oncology franchise and the urgency of portfolio diversification amid vaccine softness and late-cycle pressures. Source

This report summarizes Merck’s top medicines by Q3 2025 sales and contextualizes performance trends visible in the quarter.

Merck Q3 2025 Pharmaceutical Sales Summary

Merck reported $17.3 billion in total worldwide sales for Q3 2025. The $15.61 billion figure shown below reflects pharmaceutical segment sales only. Lynparza and Lenvima figures are Merck’s alliance profit-share revenue; Reblozyl is royalty revenue. The combined Adempas/Verquvo alliance line is Merck’s share of profits in Bayer’s territories, distinct from Merck’s separately reported Adempas product sales. The table lists selected reported revenue lines, rather than every component of pharmaceutical sales. Source

Selected Medicines by Q3 2025 Sales

Oncology Remains the Core Earnings Engine

Keytruda remained Merck’s largest product by a wide margin, generating $8.14 billion in Q3 sales and growing 10 percent year over year. The PD-1 inhibitor continues to expand across metastatic and early-stage cancer indications, maintaining its position as a cornerstone of immuno-oncology alongside Bristol Myers Squibb’s Opdivo, Roche’s Tecentriq, and AstraZeneca’s Imfinzi. Source

A notable regulatory milestone this quarter was the September 2025 approval of Keytruda QLEX, a subcutaneous formulation approved across most adult solid-tumor indications for intravenous Keytruda; administration takes approximately one minute for the three-week dose or two minutes for the six-week dose. This approval reflects a broader industry shift toward subcutaneous immunotherapies, following earlier U.S. approvals of Opdivo Qvantig and Tecentriq Hybreza. Source

Vaccine and Legacy Franchise Pressure

Combined Gardasil/Gardasil 9 sales posted a 24 percent year-over-year decline, driven primarily by weaker demand in China, with lower demand in Japan following its national catch-up immunization program. On the October 2025 earnings call, management identified private-market vaccination of adults aged 27 to 45 outside the U.S. as a growth opportunity and expected modest near-term growth. Other mature vaccine assets such as Pneumovax and RotaTeq also showed mixed performance. Source

In diabetes, Januvia and Janumet delivered strong growth, largely attributed to higher U.S. net pricing, partially offset by lower demand in China and generic competition in other international markets. Source

New Growth Drivers and Pipeline Momentum

Outside oncology, Merck highlighted strong early uptake of Winrevair, which reached $360 million in Q3 sales following its launch, with more than 24,000 prescriptions dispensed in the U.S. during the quarter. Update — October 2025, after the quarter ended: the completed acquisition of Verona Pharma added Ohtuvayre, an inhaled dual PDE3/PDE4 inhibitor for COPD maintenance treatment in adults, strengthening Merck’s cardio-pulmonary portfolio. Source

In the pipeline, Merck reported in September 2025 that enlicitide decanoate (MK-0616), an investigational oral PCSK9 inhibitor, demonstrated encouraging Phase 3 results in the CORALreef Lipids trial, with statistically significant LDL-C reductions versus placebo at Week 24. These results position Merck within a competitive and rapidly evolving lipid-lowering landscape. In a subsequent development, the FDA approved enlicitide as Lipfendra on July 15, 2026, alongside diet and exercise to lower LDL-C in adults with hypercholesterolemia, including heterozygous familial hypercholesterolemia. Source

Takeaway

Merck’s Q3 2025 earnings underscore both the resilience of its oncology franchise and the strategic importance of diversification as Keytruda approaches loss of exclusivity. While vaccine softness and legacy product declines persist, momentum from newer launches and late-stage pipeline assets will be critical in shaping Merck’s post-2028 earnings trajectory.