Merck stock steady as oncology and vaccine revenue underpin valuation

Merck & Co. (ISIN US58933Y1055) reported higher group revenue and stronger profitability in its latest annual results, with key contributions from oncology and vaccines helping to support Merck stock despite patent expiries in other franchises. According to the companys 2023 annual reporting, revenue grew compared with the prior year as cancer therapy and vaccine sales offset a sharp decline in COVID-19 treatment revenue.

Revenue up as core franchises grow

In its full-year 2023 results, Merck stated that total revenue reached approximately $60.1 billion, compared with around $59.3 billion in 2022, reflecting an increase year on year as cancer drugs and vaccines expanded. Oncology product revenue, led by the immuno-oncology therapy Keytruda, rose clearly faster than the group average, while vaccine sales, including human papillomavirus and pneumococcal vaccines, added further growth.

Within this total, Merck indicated that Keytruda generated roughly $25 billion of revenue in 2023, up from about $20.9 billion in 2022, which represents an increase of more than $4 billion year on year. The company also reported that sales of its human papillomavirus vaccine Gardasil and Gardasil 9 were about $8.9 billion in 2023, compared with approximately $6.9 billion in 2022, an increase of around $2 billion over the prior year.

Patent expiries offset by oncology and vaccines

Merck noted that the loss of exclusivity for the diabetes franchise around sitagliptin-based medicines such as Januvia and Janumet weighed on revenue in 2023, but that this headwind was partially offset by the strong performance of oncology and vaccines. The company indicated that revenue from its COVID-19 antiviral Lagevrio declined markedly in 2023 compared with 2022 as pandemic-related demand normalized, while its core oncology and vaccine portfolios continued to expand.

Management has emphasized that the growing share of oncology and vaccines in the overall product mix is intended to reduce dependence on any single franchise and to support earnings resilience as older medicines face competition. In operational terms, Merck highlighted continued clinical development investments in next-generation cancer treatments and preventive vaccines, with the goal of sustaining revenue growth in the second half of the decade.

Keytruda drives more than $25 billion

Keytruda, Mercks flagship immuno-oncology therapy for multiple cancer indications, remained the single largest product in the portfolio in 2023. The company disclosed that Keytruda revenue of roughly $25 billion in 2023 compared with about $20.9 billion in 2022 represented a year-on-year increase of more than 20 percent in absolute dollar terms. This pace of growth signals that oncology continues to be the central driver of Mercks valuation and long-term strategy.

Merck has also highlighted that Keytruda is being evaluated and used in combination regimens across a range of tumor types, which can expand its addressable market and potentially lengthen its growth runway. The companys R&D disclosures show a broad pipeline of oncology assets, including additional checkpoint inhibitors and targeted therapies intended to complement or eventually follow Keytruda as the standard of care in selected indications.

Gardasil revenue approaches $9 billion

Alongside oncology, vaccines are an increasingly important pillar of Mercks revenue profile. In 2023, Gardasil and Gardasil 9 together delivered approximately $8.9 billion of revenue, up from about $6.9 billion in 2022, according to the companys reported figures. This represents an increase of about $2 billion year on year, reflecting higher demand for human papillomavirus vaccination programs in multiple markets.

Merck has pointed to continued expansion in vaccination coverage, particularly in emerging economies where HPV vaccination rates still have room to grow. The company notes that expanded access programs and collaborations with public-health agencies could support further volume increases over time, while pricing and mix effects may also influence revenue growth from this franchise.

Pneumococcal vaccines add to diversified base

Beyond Gardasil, Merck reports that its pneumococcal vaccines, including Vaxneuvance, contributed to vaccine segment growth in 2023. The company has focused on broadening label indications and demonstrating effectiveness against additional pneumococcal serotypes, which can help to differentiate its products versus competitors in the adult and pediatric vaccine markets.

The expansion of Vaxneuvance and other vaccines provides Merck with a diversified immunization portfolio alongside HPV, shingles, and pediatric combinations. This diversification is strategically relevant because it mitigates the impact of patent cliffs and competitive pressures on individual products and supports more stable cash flow generation to fund ongoing R&D.

Profitability and investment in R&D

Mercks 2023 results also showed higher profitability compared with the prior year. The company indicated that non-GAAP earnings per share rose year on year, benefiting from higher sales in oncology and vaccines and from cost discipline, even as it continued to invest heavily in research and development. R&D expenses remained substantial as a proportion of revenue, underlining the companys focus on pipeline renewal and life-cycle management for existing medicines.

From an investor perspective, this balance between near-term earnings delivery and long-term investment is central to the Merck equity story. The companys ability to generate strong cash flows from its marketed products while funding late-stage clinical programs is a key consideration for assessing the sustainability of dividend payments and potential future capital returns.

Guidance framed by growth and headwinds

In its communications around the 2023 results, Merck provided guidance that reflected both the growth momentum from Keytruda, Gardasil, and vaccines and the negative impact from generic competition in older franchises and the declining contribution from COVID-19 antiviral sales. Management outlined expectations for continued double-digit growth in oncology and vaccines, while acknowledging that overall revenue growth may be moderated by these offsetting factors.

The company has stressed that its strategic priority is to extend the lifecycle of Keytruda through new indications and combination regimens, while also advancing next-generation oncology assets and vaccines. This guidance provides a framework for how Merck aims to navigate the mid-term period ahead of future patent expiries in its core portfolio.

R&D pipeline and business development

Merck continues to pursue an active strategy of internal R&D and external business development to strengthen its portfolio. The companys pipeline includes multiple late-stage candidates in oncology, vaccines, cardiometabolic disease, and immunology. It has also engaged in collaborations and acquisitions intended to access novel modalities such as antibody-drug conjugates and next-generation vaccines.

These pipeline and deal activities are designed to ensure that Merck has additional growth drivers beyond Keytruda and Gardasil as the decade progresses. Investors often evaluate the probability of success, expected market size, and timing of these pipeline assets when forming expectations for Mercks long-term revenue and earnings trajectory.

Product focus: Keytruda as cornerstone therapy

Keytruda has become a cornerstone of modern immuno-oncology. The monoclonal antibody targets the PD-1 pathway and is used in a wide range of cancer types, including melanoma, non-small cell lung cancer, and certain head and neck cancers. Its broad label and growing number of approved indications have made it a key revenue and profit contributor for Merck.

The company reports that continued clinical development of Keytruda in earlier lines of therapy and adjuvant settings offers additional potential for revenue growth. At the same time, Merck is investing in new oncology assets that may enhance or complement the activity of Keytruda, including combination regimens designed to overcome resistance mechanisms in certain tumors.

Merck stock and market context

Merck stock trades in the United States as a major component of large-cap healthcare indices, reflecting its scale and importance in the global pharmaceutical sector. The companys market capitalization, measured in recent months, has typically been in the range of hundreds of billions of US dollars, aligning it with other leading global pharmaceutical groups.

For investors, the strategic question is how Mercks growth in oncology and vaccines will balance patent expiries and competitive pressures in other parts of the portfolio over the coming years. The companys recent revenue and product trends, including the increase in total revenue from about $59.3 billion in 2022 to roughly $60.1 billion in 2023 and the expansion of Keytruda and Gardasil sales, provide a quantitative basis for assessing that balance.