Exhibit 99.1

News Release

FOR IMMEDIATE RELEASE

Merck Announces Third-Quarter 2020 Financial Results

KENILWORTH, N.J., Oct. 27, 2020 – Merck (NYSE: MRK), known as MSD outside the United States and Canada, today announced financial results for the third quarter of 2020.

“We continue to execute on our strategic priorities and remain confident we will achieve solid full-year revenue growth despite the impact of the ongoing COVID-19 pandemic. Demand for our products remains robust, and production, supply and distribution of our medicines, vaccines and animal health products are moving forward with minimal disruption,” said Kenneth C. Frazier, chairman and chief executive officer, Merck. “I am confident in our ability to advance our promising pipeline and clinical trials despite the challenging environment, and I believe that our leadership and track record of solid commercial execution will continue to drive long-term growth.”

Financial Summary

*Refer to table on page 11.

GAAP (generally accepted accounting principles) earnings per share assuming dilution (EPS) was $1.16 for the third quarter of 2020. Non-GAAP EPS of $1.74 for the third quarter of 2020 excludes acquisition- and divestiture-related costs, restructuring costs, pretax charges of $1.1 billion related to certain license and collaboration agreements, and certain other items. Year-to-date results can be found in the attached tables.

COVID-19 Research Highlights

Building on the company’s experience with antivirals and vaccines, Merck advanced its multiple scientific programs in an effort to help combat SARS-CoV-2, specifically,

Oncology Pipeline Highlights

Merck continued to advance the development programs for KEYTRUDA (pembrolizumab), the company’s anti-PD-1 therapy; Lynparza (olaparib), a PARP inhibitor being co-developed and co-commercialized with AstraZeneca; and Lenvima (lenvatinib mesylate), an orally available tyrosine kinase inhibitor being co-developed and co-commercialized with Eisai Co., Ltd. (Eisai), in addition to other notable developments as follows:

Other Pipeline Highlights

Business Developments

Organon & Co.

Third-Quarter Financial Impact of COVID-19

In the third quarter, the estimated negative impact of the COVID-19 pandemic to Merck’s pharmaceutical revenue was approximately $475 million, bringing the company’s year-to-date negative impact on revenue to approximately $2.1 billion. Lower back-to-school demand negatively impacted vaccine sales, in particular GARDASIL 9 (Human Papillomavirus 9-valent Vaccine, Recombinant) in the U.S. In addition, access to health care providers remains reduced, although improved from the second quarter. The negative impact to Animal Health sales in the third quarter was immaterial.

Operating expenses were positively impacted in the third quarter by approximately $115 million, primarily driven by lower promotional and selling costs as well as lower research and development (R&D) expenses, net of investments in COVID-19-related antiviral and vaccine research programs.

Third-Quarter Revenue Performance

The following table reflects sales of the company’s top pharmaceutical products, as well as sales of animal health products.

*Alliance revenue for these products represents Merck’s share of profits, which are product sales net of cost of sales and commercialization costs.

**Other revenues are comprised primarily of third-party manufacturing sales and miscellaneous corporate revenues, including revenue hedging activities.

Pharmaceutical Revenue

Third-quarter pharmaceutical sales increased by $225 million, or 2%, to $11.3 billion. The increase was driven primarily by growth in oncology and certain hospital acute care products, partially offset by the negative impact of the COVID-19 pandemic and the ongoing impacts of the loss of market exclusivity for several products.

Growth in oncology was largely driven by higher sales of KEYTRUDA, which grew 21% to $3.7 billion in the quarter. In the U.S., sales of KEYTRUDA grew 24% to $2.2 billion. Global sales growth of KEYTRUDA reflects continued strong momentum from the NSCLC indications as well as continued uptake in other indications, including adjuvant melanoma, RCC, bladder, head and neck squamous cell carcinoma (HNSCC) and microsatellite instability-high (MSI-H) cancers as well as uptake following the recent launch of the Q6W dosing regimen in the U.S., partially offset by the negative impacts of the COVID-19 pandemic and pricing in Japan. Also contributing to growth in oncology was higher alliance revenue related to Lynparza and Lenvima reflecting continued uptake in approved indications in the U.S., Europe and China.

Performance in hospital acute care reflects higher demand globally for BRIDION (sugammadex), a medicine for the reversal of neuromuscular blockade induced by rocuronium bromide or vecuronium bromide in adults undergoing surgery and the ongoing launch of PREVYMIS (letermovir), a medicine for prophylaxis (prevention) of cytomegalovirus (CMV) infection and disease in adult CMV-seropositive recipients of an allogeneic hematopoietic stem cell transplant.

In addition, sales of JANUVIA (sitagliptin) and JANUMET (sitagliptin and metformin HCI) increased slightly in the quarter reflecting strong demand from certain international markets, partially offset by continued pricing pressure in the U.S.

Vaccine sales performance reflects higher sales of PNEUMOVAX 23 (pneumococcal vaccine polyvalent), a vaccine to help prevent pneumococcal disease, primarily driven by higher volumes in the U.S., Europe and Japan attributable in part to increased demand for pneumococcal vaccination during the COVID-19 pandemic.

Vaccine sales were negatively affected by declines in sales of GARDASIL [Human Papillomavirus Quadrivalent (Types 6,11,16 and 18) Vaccine, Recombinant]/GARDASIL 9, vaccines to prevent certain cancers and other diseases caused by HPV, largely due to lower demand in the U.S. and Hong Kong, SAR, PRC attributable to the COVID-19 pandemic, partially offset by higher volumes in China and in Europe.

Combined sales of pediatric vaccines VARIVAX (Varicella Virus Vaccine Live), a vaccine to help prevent chickenpox; PROQUAD (Measles, Mumps, Rubella and Varicella Virus Vaccine Live), a combination vaccine to help protect against measles, mumps, rubella and varicella; and M-M-R II (Measles, Mumps and Rubella Virus Vaccine Live), a vaccine to help prevent measles, mumps and rubella, declined in the third quarter, primarily due to lower demand in the U.S. related to the COVID-19 pandemic.

Pharmaceutical sales in the quarter were negatively affected by the ongoing impacts from the loss of market exclusivity, including for NUVARING (etonogestrel/ethinyl estradiol vaginal ring), NOXAFIL (posaconazole) and EMEND (aprepitant)/EMEND (fosaprepitant dimeglumine) for Injection.

Animal Health Revenue

Animal Health sales totaled $1.2 billion in the third quarter of 2020, an increase of 9% compared with the third quarter of 2019; excluding the unfavorable effect from foreign exchange, Animal Health sales grew 12%. Growth in companion animal products was driven largely by higher demand in companion animal vaccines and higher demand for the BRAVECTO (fluralaner) line of products for parasitic control. Performance in livestock products reflects higher demand globally for ruminant, poultry and swine products.

Third-Quarter Expense, EPS and Related Information

The tables below present selected expense information.

GAAP Expense, EPS and Related Information

Gross margin was 72.3% for the third quarter of 2020 compared to 67.8% for the third quarter of 2019. The increase reflects lower acquisition- and divestiture-related costs and the favorable effect of product mix, partially offset by the unfavorable effects of pricing pressure, inventory write-offs, higher amortization of intangible assets related to collaborations and foreign exchange.

Selling, general and administrative expenses were $2.5 billion in the third quarter of 2020, a decrease of 5% compared to the third quarter of 2019. The decrease primarily reflects lower administrative and selling costs, including less travel and meeting expenses, due in part to the COVID-19 pandemic, partially offset by higher acquisition- and divestiture-related costs, primarily reflecting costs related to the company’s planned spinoff of Organon.

Research and development expenses were $3.4 billion in the third quarter of 2020, an increase of 6% compared with the third quarter of 2019. The increase was primarily driven by higher upfront payments related to collaborations and license agreements, higher expenses related to clinical development and increased investment in discovery research and early drug development, partially offset by lower charges for the acquisitions of businesses, as well as lower laboratory, travel and meeting expenses due to the COVID-19 pandemic.

Other (income) expense, net, was $312 million of income in the third quarter of 2020 compared to $35 million of expense in the third quarter of 2019, primarily due to higher income from investments in equity securities, net, which was $360 million in 2020 compared with $16 million in 2019, largely from the recognition of unrealized gains on securities.

The effective income tax rate was 14.1% for the third quarter of 2020 compared to 18.7% in the third quarter of 2019. The effective income tax rate in 2019 reflects the unfavorable impact of a charge for the acquisition of Peloton Therapeutics, Inc. (Peloton) for which no tax benefit was recognized.

GAAP EPS was $1.16 for the third quarter of 2020 compared with $0.74 for the third quarter of 2019.

Non-GAAP Expense, EPS and Related Information

Non-GAAP gross margin was 74.8% for the third quarter of 2020 compared to 75.9% for the third quarter of 2019. The decrease in non-GAAP gross margin reflects the unfavorable effects of pricing pressure, inventory write-offs, higher amortization of intangible assets related to collaborations and foreign exchange, partially offset by the favorable effect of product mix.

Non-GAAP selling, general and administrative expenses were $2.2 billion in the third quarter of 2020, a decrease of 13% compared to the third quarter of 2019. The decrease primarily reflects lower administrative and selling costs, including less travel and meeting expenses, due in part to the COVID-19 pandemic.

Non-GAAP R&D expenses were $2.3 billion in the third quarter of 2020, a 3% increase compared to the third quarter of 2019. The increase was primarily driven by higher expenses related to clinical development and increased investment in discovery research and early drug development, partially offset by lower laboratory, travel and meeting expenses due to the COVID-19 pandemic.

Non-GAAP other (income) expense, net, was $311 million of income in the third quarter of 2020 compared to $29 million of expense in the third quarter of 2019, primarily due to higher income from investments in equity securities, net, which was $360 million in 2020 compared with $16 million in 2019, largely from the recognition of unrealized gains on securities.

The non-GAAP effective income tax rate was 14.8% for the third quarter of 2020 compared to 15.7% for the third quarter of 2019, reflecting the favorable impact of earnings mix.

Non-GAAP EPS was $1.74 for the third quarter of 2020 compared with $1.51 for the third quarter of 2019.

A reconciliation of GAAP to non-GAAP net income and EPS is provided in the table that follows.

Financial Outlook

The updated full-year guidance that Merck is providing below includes its current assumption of the impact from the COVID-19 pandemic, which is expected to continue to be offset by favorability from underlying business strength. The company continues to assume that the majority of the negative impact occurred during the second quarter. However, it now expects some residual negative impacts in the fourth quarter, largely in Europe and certain emerging markets. In addition, the phasing of the recovery of GARDASIL 9 demand is slower than originally anticipated, in particular in the U.S.

For the full-year 2020, Merck now expects an unfavorable impact to revenue of approximately $2.35 billion (excluding the impact of foreign exchange) due to the COVID-19 pandemic, comprised of approximately $2.3 billion for pharmaceuticals and approximately $50 million for Animal Health, including the impacts in the first three quarters of the year.

For the full-year 2020, Merck now expects a net favorable impact to operating expenses of approximately $625 million, reflecting continued lower spending due to the COVID-19 pandemic, partially offset by spending on its COVID-19-related antiviral and vaccine research programs.

Merck narrowed and raised its full-year 2020 revenue range to be between $47.6 billion and $48.6 billion, including a negative impact from foreign exchange of approximately 1.5% at mid-October exchange rates. The company’s guidance assumes $120 million of revenue for the replenishment of doses of GARDASIL 9 that were borrowed from the U.S. Centers for Disease Control and Prevention (CDC) Pediatric Vaccine Stockpile in the fourth quarter of 2019.

Merck narrowed and lowered its full-year 2020 GAAP EPS range to be between $4.55 and $4.65. Merck narrowed and raised its full-year 2020 non-GAAP EPS range to be between $5.91 and $6.01, including a negative impact from foreign exchange of approximately 2.5% at mid-October exchange rates. The non-GAAP range excludes acquisition- and divestiture-related costs, costs related to restructuring programs and certain other items.

The following table summarizes the company’s full-year 2020 financial guidance.

*The company does not have any non-GAAP adjustments to revenue.

**EPS guidance for 2020 assumes a share count (assuming dilution) of approximately 2.54 billion shares.

A reconciliation of anticipated 2020 GAAP EPS to non-GAAP EPS and the items excluded from non-GAAP EPS are provided in the table below.

Earnings Conference Call

Investors, journalists and the general public may access a live audio webcast of the call today at 8:00 a.m. EDT on Merck’s website at https://www.merck.com/investor-relations/events-and-presentations/. Institutional investors and analysts can participate in the call (833) 353-0277 or toll free (469) 886-1947 and using ID code number 4664137. Members of the media are invited to monitor the call by dialing (833) 353-0277 or toll free (469) 886-1947 and using ID code number 4664137. Journalists who wish to ask questions are requested to contact a member of Merck’s Media Relations team at the conclusion of the call.

About Merck

For more than 125 years, Merck, known as MSD outside of the United States and Canada, has been inventing for life, bringing forward medicines and vaccines for many of the world’s most challenging diseases in pursuit of our mission to save and improve lives. We demonstrate our commitment to patients and population health by increasing access to health care through far-reaching policies, programs and partnerships. Today, Merck continues to be at the forefront of research to prevent and treat diseases that threaten people and animals – including cancer, infectious diseases such as HIV and Ebola, and emerging animal diseases – as we aspire to be the premier research-intensive biopharmaceutical company in the world. For more information, visit www.merck.com and connect with us on Twitter, Facebook, Instagram, YouTube and LinkedIn.

Forward-Looking Statement of Merck & Co., Inc., Kenilworth, N.J., USA

This news release of Merck & Co., Inc., Kenilworth, N.J., USA (the “company”) includes “forward-looking statements” within the meaning of the safe harbor provisions of the U.S. Private Securities Litigation Reform Act of 1995. These statements are based upon the current beliefs and expectations of the company’s management and are subject to significant risks and uncertainties. There can be no guarantees with respect to pipeline products that the products will receive the necessary regulatory approvals or that they will prove to be commercially successful. If underlying assumptions prove inaccurate or risks or uncertainties materialize, actual results may differ materially from those set forth in the forward-looking statements.

Risks and uncertainties include but are not limited to, general industry conditions and competition; general economic factors, including interest rate and currency exchange rate fluctuations; the impact of the global outbreak of novel coronavirus disease (COVID-19); the impact of pharmaceutical industry regulation and health care legislation in the United States and internationally; global trends toward health care cost containment; technological advances, new products and patents attained by competitors; challenges inherent in new product development, including obtaining regulatory approval; the company’s ability to accurately predict future market conditions; manufacturing difficulties or delays; financial instability of international economies and sovereign risk; dependence on the effectiveness of the company’s patents and other protections for innovative products; and the exposure to litigation, including patent litigation, and/or regulatory actions.

The company undertakes no obligation to publicly update any forward-looking statement, whether as a result of new information, future events or otherwise. Additional factors that could cause results to differ materially from those described in the forward-looking statements can be found in the company’s 2019 Annual Report on Form 10-K and the company’s other filings with the Securities and Exchange Commission (SEC) available at the SEC’s Internet site (www.sec.gov).

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MERCK & CO., INC.

CONSOLIDATED STATEMENT OF INCOME - GAAP

(AMOUNTS IN MILLIONS, EXCEPT PER SHARE FIGURES)

(UNAUDITED)

Table 1

MERCK & CO., INC.

GAAP TO NON-GAAP RECONCILIATION

THIRD QUARTER 2020

(AMOUNTS IN MILLIONS, EXCEPT PER SHARE FIGURES)

(UNAUDITED)

Table 2a

MERCK & CO., INC.

GAAP TO NON-GAAP RECONCILIATION

NINE MONTHS ENDED SEPTEMBER 30, 2020

(AMOUNTS IN MILLIONS, EXCEPT PER SHARE FIGURES)

(UNAUDITED)

Table 2b

MERCK & CO., INC.

FRANCHISE / KEY PRODUCT SALES

(AMOUNTS IN MILLIONS)

(UNAUDITED)

Table 3