Form 8-K

8-K — Merck & Co., Inc.

Accession: 0001104659-26-119825

Filed: 2026-10-29

Period: 2026-10-29

CIK: 0000310158

SIC: 2834 (PHARMACEUTICAL PREPARATIONS)

Item: Results of Operations and Financial Condition

Item: Financial Statements and Exhibits

Documents

8-K — tm2628203d1_8k.htm (Primary)

EX-99.1 — EXHIBIT 99.1 (tm2628203d1_ex99-1.htm)

EX-99.2 — EXHIBIT 99.2 (tm2628203d1_ex99-2.htm)

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 OR 15(d) of

The Securities Exchange Act of 1934

Date of Report (Date of earliest event

reported) October 29, 2026 (October 29, 2026)

Merck & Co., Inc.

(Exact name of registrant as specified in

its charter)

New Jersey

(State

or other jurisdiction

of incorporation)

1-6571

(Commission File Number)

22-1918501

(I.R.S

Employer Identification No.)

126

East Lincoln Avenue

Rahway

New

Jersey    07065

(Address of principal executive offices)  (Zip Code)

(Registrant’s telephone number, including

area code) (908) 740-4000

Not applicable

(Former name, former address and former fiscal year, if changed since last report.)

Check the appropriate box below if the Form 8-K filing is intended

to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class

Trading Symbol(s)

Name of each exchange on which registered

Common

Stock ($0.50 par value)

MRK

New York Stock Exchange

3.250% Notes due 2032

MRK/32

New York Stock Exchange

2.500% Notes due 2034

MRK/34

New York Stock Exchange

1.375% Notes due 2036

MRK 36A

New York Stock Exchange

3.500% Notes due 2037

MRK/37

New York Stock Exchange

3.700% Notes due 2044

MRK/44

New York Stock Exchange

3.750% Notes due 2054

MRK/54

New York Stock Exchange

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ¨

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ¨

Item

2.02. Results of Operations and Financial Condition.

The following information, including the exhibits

hereto, is being furnished pursuant to this Item 2.02.

Incorporated by reference is a press release issued by Merck &

Co., Inc. on October 29, 2026, regarding earnings for the third quarter of 2026, attached as Exhibit 99.1. Also incorporated by reference

is certain supplemental information not included in the press release, attached as Exhibit 99.2.

This information shall not be deemed to be “filed”

for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to

the liabilities of that Section, and is not incorporated by reference in any filing under the Securities Act of 1933, as amended, or the

Exchange Act, except as expressly set forth by specific reference in such filing.

Item 9.01. Financial Statements and Exhibits.

(d) Exhibits

Exhibit 99.1

Press release issued

October 29, 2026, regarding earnings for the third quarter of 2026

Exhibit 99.2

Certain supplemental information

not included in the press release

Exhibit 104

Cover Page Interactive Data File (embedded within the Inline XBRL document)

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf

by the undersigned hereunto duly authorized.

Merck & Co., Inc.

Date: October 29, 2026

By:

/s/

Kelly E. W. Grez

Kelly

E. W. Grez

Corporate Secretary

EX-99.1 — EXHIBIT 99.1

EX-99.1

Filename: tm2628203d1_ex99-1.htm · Sequence: 2

Exhibit 99.1

- 1 -

News Release

Merck & Co., Inc., Rahway, N.J.,

USA Announces Third-Quarter 2026 Financial Results; Highlights Multiple Milestones Advancing Broad, Diverse Pipeline

Sales Growth Reflects Continued Strength in

Oncology and Animal Health, Plus Contributions From Other Products in Broader Portfolio, Including WINREVAIR

Financial Highlights

- Total Worldwide Sales Were $18.1 Billion (5% Growth; 4% Growth ex-FX)

o KEYTRUDA/KEYTRUDA QLEX1 Sales Were $8.6 Billion (6% Growth;

6% Growth ex-FX); Includes KEYTRUDA QLEX Sales of $830 Million

o WINREVAIR Sales Were $694 Million (93% Growth; 94% Growth ex-FX)

o Animal Health Sales Were $1.7 Billion (4% Growth; 3% Growth ex-FX)

- GAAP EPS Was $2.04; Non-GAAP EPS Was $2.49; GAAP and Non-GAAP EPS

Include a One-Time Charge of $0.12 per Share Related to a Global License Agreement With

SciBrunch

Pipeline & Portfolio Highlights

- Presented First-Time Pivotal Data From Phase 3 Trials Across Robust

Oncology Pipeline at ESMO Congress 2026, Including:

o TroFuse-005 Trial Evaluating Sacituzumab Tirumotecan (sac-TMT) in

Certain Patients With Advanced or Recurrent Endometrial Cancer; U.S. FDA Accepted for Priority

Review a Biologics License Application Based on These Data

o INTerpath-001 Trial Evaluating Intismeran Autogene Plus KEYTRUDA as

Adjuvant Treatment for Patients With Resected Stage IIB-IV Melanoma, in Collaboration With

Moderna

- Announced Positive Phase 2b Results in Moderate to Severe Hidradenitis

Suppurativa From Clinical Study of Investigational Immunology Candidate Tulisokibart

- Presented One-Year Results From Phase 2b/3 BRUNELLO Trial Evaluating

Remigromig in Adults With Diabetic Macular Edema

Full-Year 2026 Financial Outlook

- Narrows and Raises the Midpoint of Worldwide Sales Range; Now Expects

Sales To Be Between $66.8 Billion and $67.3 Billion

Available in some markets as KEYTRUDA SC.

- 2 -

- Narrows and Raises Expected Non-GAAP EPS Range To Be Between $2.77

and $2.82; Outlook Now Includes One-Time Charge of $0.12 per Share Related to the Global

License Agreement With SciBrunch

RAHWAY, N.J., Oct. 29, 2026 – Merck & Co., Inc.,

Rahway, N.J., USA (NYSE: MRK), known as MSD outside the United States and Canada, today announced financial results for the third quarter

of 2026.

“Our science-led strategy is transforming

our business,” said Robert M. Davis, chairman and chief executive officer. “The potentially practice-changing advances in

oncology presented at last weekend’s ESMO meeting, including new data for our antibody-drug conjugate sac-TMT and the first Phase

3 validation of a therapeutic cancer vaccine, further clinically de-risk the substantial long-term opportunity of our late-phase pipeline.

With positive momentum across multiple therapeutic areas, I’m increasingly confident in our ability to deliver long-term value

for patients and shareholders.”

Financial Summary

Third Quarter

$ in millions, except EPS amounts

2026

2025

Change

Change Ex-

Exchange

Sales

$ 18,085

$ 17,276

5 %

4 %

GAAP net income2

5,065

5,785

-12 %

-14 %

Non-GAAP net income that

excludes certain items2,3*

6,159

6,448

-4 %

-5 %

GAAP EPS

2.04

2.32

-12 %

-13 %

Non-GAAP EPS that excludes certain

items3*

2.49

2.58

-3 %

-5 %

*Refer to table on page 7.

For the third quarter of 2026, Generally Accepted

Accounting Principles (GAAP) earnings per share (EPS) assuming dilution was $2.04 and non-GAAP EPS was $2.49. Both GAAP and non-GAAP

EPS in the third quarter of 2026 include a one-time charge of $0.12 per share related to a global license agreement with SciBrunch Therapeutics

Co., Ltd. (SciBrunch). Both GAAP and non-GAAP EPS in the third quarter of 2025 include a charge of $0.10 per share for a milestone

payment to LaNova Medicines Ltd. (LaNova, acquired by Sino Biopharmaceutical Limited) associated with the technology transfer for MK-2010.

Non-GAAP EPS excludes acquisition- and divestiture-related

costs and costs related to restructuring programs, as well as income and losses from investments in equity securities. Non-GAAP EPS in

the third quarter of 2025 also excludes tax expense relating to audit reserve adjustments.

Net income attributable to the Company.

The Company is providing certain 2026 and 2025 non-GAAP information that excludes certain items because of the nature of these items

and the impact they have on the analysis of underlying business performance and trends. Management believes that providing this information

enhances investors’ understanding of the Company’s results because management uses non-GAAP results to assess performance.

Management uses non-GAAP measures internally for planning and forecasting purposes and to measure the performance of the Company along

with other metrics. In addition, annual employee compensation, including senior management’s compensation, is derived in part using

a non-GAAP pretax income metric. This information should be considered in addition to, but not as a substitute for or superior to, information

prepared in accordance with GAAP. For a description of the non-GAAP adjustments, see Table 2a attached to this release.

- 3 -

Year-to-date results can be found in the attached

tables.

Third-Quarter Sales Performance

The following table reflects sales of the Company’s

top products and significant performance drivers.

Third Quarter

$ in millions

2026

2025

Change

Change Ex-

Exchange

Commentary

Total Sales

$ 18,085

$ 17,276

5 %

4 %

Pharmaceutical

16,268

15,611

4 %

Increase primarily driven by growth in

KEYTRUDA/KEYTRUDA QLEX, WINREVAIR, GARDASIL/GARDASIL 9, WELIREG, ENFLONSIA and the inclusion of OHTUVAYRE sales. Growth benefited

from the timing of purchases by approximately $550 million. Growth was partially offset by declines in BRIDION, JANUVIA/JANUMET

and LAGEVRIO, as well as lower alliance revenue related to Koselugo.

KEYTRUDA/

KEYTRUDA QLEX

8,601

8,147

6 %

Growth primarily driven by strong global

uptake in earlier-stage indications including triple-negative breast cancer, cervical cancer, head and neck cancer and bladder cancer,

as well as higher global demand in metastatic indications, including urothelial cancer. Timing of wholesaler purchases unfavorably

affected sales in the U.S. but was largely offset by a benefit from increased inventory in the channel. Sales of KEYTRUDA QLEX were

$830 million.

GARDASIL/GARDASIL 9

1,995

1,749

14 %

Increase primarily due to higher sales

in the U.S. reflecting favorable public-sector purchasing patterns and higher net pricing.

PROQUAD, M-M-R II and VARIVAX

730

684

7 %

Increase primarily due to higher demand

in certain European markets.

WINREVAIR

694

360

93 %

94 %

Growth primarily reflects higher demand

and favorable wholesaler and specialty pharmacy purchasing patterns in the U.S., as well as launch uptake in certain international

markets, particularly in Europe and Japan.

JANUVIA/JANUMET

380

624

-39 %

Decline primarily driven by lower demand

due to generic competition following loss of market exclusivity in the U.S.

Lynparza*

352

379

-7 %

Decline primarily due to lower net pricing

in the U.S. and lower demand and pricing in China.

PREVYMIS

347

266

30 %

31 %

Increase primarily due to higher demand

globally.

- 4 -

Third Quarter

$ in millions

2026

2025

Change

Change Ex-

Exchange

Commentary

WELIREG

307

196

56 %

58 %

Growth

primarily driven by higher demand in the U.S. and continued launch uptake in international markets, particularly in Japan.

Lenvima*

287

258

11 %

Growth primarily

due to higher demand in the U.S.

CAPVAXIVE

263

244

8 %

7 %

Increase primarily

driven by launch uptake in several international markets, particularly in Asia Pacific and Europe, partially offset by lower sales

in the U.S. reflecting lower adult pneumococcal vaccination rates and lower net pricing.

ENFLONSIA

187

138 %

136 %

Increase primarily

driven by seasonal demand and associated inventory build in the U.S. and certain international markets.

OHTUVAYRE

184

Product obtained

as part of the Company's October 2025 acquisition of Verona Pharma plc.

BRIDION

144

439

-67 %

Decline primarily

driven by lower demand in the U.S. due to generic competition following loss of market exclusivity.

LAGEVRIO

138

-88 %

Decline largely

due to lower demand in Japan.

Animal Health

1,676

1,615

4 %

3 %

Growth attributable

to both Livestock and Companion Animal product portfolios.

Livestock

1,048

1,023

2 %

Growth primarily

driven by higher demand for poultry products.

Companion Animal

628

592

6 %

Growth largely driven

by new product launches. Sales of BRAVECTO line of products were $264 million and $262 million in the current and prior-year quarters,

respectively, which represents an increase of 1%, or flat excluding impact of foreign exchange.

Other Revenues**

141

185 %

-25 %

Increase primarily

due to favorable impact of revenue-hedging activities, partially offset by lower revenue from third-party manufacturing arrangements.

*Alliance revenue for this product represents the

Company’s share of profits, which are product sales net of cost of sales and commercialization costs.

**Other revenues are comprised primarily of revenues

from third-party manufacturing arrangements and miscellaneous corporate revenues, including revenue-hedging activities.

In addition, Koselugo alliance revenue was $13

million in the third quarter of 2026 compared with $214 million in the third quarter of 2025. The decrease was due to an amendment to

the collaboration agreement with AstraZeneca in 2025, which discontinued the provisions whereby the Company shared revenue and costs

with AstraZeneca, and revised the payment structure, resulting in the Company’s recognition of a $150 million upfront payment and

a $50 million regulatory milestone in the third quarter of 2025.

- 5 -

Third-Quarter Expense and Related Information

The table below presents selected expense information.

$ in millions

GAAP

Acquisition-

and

Divestiture-

Costs4

Restructuring

Costs

(Income)

Loss From

Investments

in Equity

Securities

Non-

GAAP3

Third Quarter 2026

Cost of sales

$ 4,892

$ 1,140

$ 396

$ -

$ 3,356

Selling, general and administrative

2,886

2,862

Research and development

4,537

4,533

Restructuring costs

184

Other (income) expense, net

(393 )

420

Third Quarter 2025

Cost of sales

$ 3,855

$ 621

$ 110

$ -

$ 3,124

Selling, general and administrative

2,633

2,599

Research and development

4,234

233

3,997

Restructuring costs

Other (income) expense, net

(238 )

(344 )

106

GAAP Expense, EPS and Related Information

Gross margin was 72.9% for the third quarter of

2026 compared with 77.7% for the third quarter of 2025. The decrease was primarily due to higher amortization of intangible assets, restructuring

costs and production costs.

Selling, general and administrative (SG&A)

expenses were $2.9 billion in the third quarter of 2026, an increase of 10% compared with the third quarter of 2025. The increase was

primarily due to higher administrative costs, as well as higher promotional costs in support of product launches.

Research and development (R&D) expenses were

$4.5 billion in the third quarter of 2026, an increase of 7% compared with the third quarter of 2025. The increase was primarily due

to a $400 million charge related to a global license agreement with SciBrunch and higher clinical development spending, partially offset

by lower restructuring costs and a $200 million reduction in R&D expenses as part of a funding agreement with Blackstone Life Sciences

(Blackstone). R&D expenses in the third quarter of 2025 include a $300 million charge for a milestone payment to LaNova for the completion

of the technology transfer for MK-2010.

Other (income) expense, net, was $27 million of

expense in the third quarter of 2026 compared with $238 million of income in the third quarter of 2025. The unfavorability was primarily

due to higher net interest expense.

Reflects expenses related to business combinations, including the amortization of intangible assets, intangible asset impairment charges,

and expense or income related to changes in the estimated fair value measurement of liabilities for contingent consideration. Also includes

integration, transaction and certain other costs associated with acquisitions and divestitures, as well as amortization of intangible

assets related to collaborations, licensing arrangements and asset acquisitions, and recognition of fair value step-up to inventories

for asset acquisitions.

- 6 -

The effective income tax rate for the third quarter

of 2026 was 8.9%, reflecting the favorable impacts of certain discrete items, as well as jurisdictional mix of income and expense.

GAAP EPS was $2.04 for the third quarter of 2026

compared with $2.32 for the third quarter of 2025. The decrease was primarily driven by higher operating expenses, reflecting increased

investments to advance the R&D pipeline and support product launches, higher amortization of intangible assets, higher net interest

expense and increased restructuring costs, partially offset by operational strength in the business and a lower effective income tax

rate.

Non-GAAP Expense, EPS and Related Information

Non-GAAP gross margin was 81.4% for the third

quarter of 2026 compared with 81.9% for the third quarter of 2025. The decrease was primarily due to higher production costs.

Non-GAAP SG&A expenses were $2.9 billion in

the third quarter of 2026, an increase of 10% compared with the third quarter of 2025. The increase was primarily due to higher administrative

costs, as well as higher promotional costs in support of product launches.

Non-GAAP R&D expenses were $4.5 billion in

the third quarter of 2026, an increase of 13% compared with the third quarter of 2025. The increase was primarily due to a $400 million

charge related to a global license agreement with SciBrunch and higher clinical development spending, partially offset by a $200 million

reduction in R&D expenses as part of a funding agreement with Blackstone. R&D expenses in the third quarter of 2025 include a

$300 million charge for a milestone payment to LaNova for the completion of the technology transfer for MK-2010.

Non-GAAP other (income) expense, net, was $420

million of expense in the third quarter of 2026 compared with $106 million of expense in the third quarter of 2025. The unfavorability

was primarily due to higher net interest expense.

The non-GAAP effective income tax rate for the

third quarter of 2026 was 10.9%, reflecting the favorable impacts of certain discrete items, as well as jurisdictional mix of income

and expense.

Non-GAAP EPS was $2.49 for the third quarter of

2026 compared with $2.58 for the third quarter of 2025. The decrease was primarily driven by higher operating expenses, reflecting increased

investments to advance the R&D pipeline and support product launches, and higher net interest expense, partially offset by operational

strength in the business and a lower effective income tax rate.

- 7 -

A reconciliation of GAAP to non-GAAP net income

and EPS is provided in the table that follows.

Third Quarter

$ in millions, except EPS

amounts

2026

2025

EPS

GAAP EPS

$ 2.04

$ 2.32

Difference

0.45

0.26

Non-GAAP

EPS that excludes items listed below3

$ 2.49

$ 2.58

Net Income

GAAP

net income2

$ 5,065

$ 5,785

Difference

1,094

663

Non-GAAP

net income that excludes items listed below2,3

$ 6,159

$ 6,448

Excluded Items:

Acquisition-

and divestiture-related costs4

$ 1,167

$ 659

Restructuring costs

581

390

Income from investments in equity securities

(393 )

(344 )

Decrease to net income before taxes

1,355

705

Estimated

income tax (benefit) expense5

(261 )

(42 )

Decrease to net income

$ 1,094

$ 663

Pipeline and Portfolio Highlights

In the third quarter, the Company achieved key

regulatory and clinical milestones to meaningfully advance its broad and diverse pipeline.

· Oncology:

o U.S. Food and Drug Administration (U.S. FDA) approved WELIREG plus

Lenvima, in collaboration with Eisai, for certain previously treated adult patients with

advanced renal cell carcinoma with a clear cell component (ccRCC), based on Phase 3 LITESPARK-011

trial.

§ Approval

represents first approved combination of an oral hypoxia-inducible factor-2 alpha inhibitor

and a multi-targeted vascular endothelial growth factor tyrosine kinase inhibitor (TKI) for

these patients.

o In October, U.S. FDA accepted a Biologics License Application (BLA)

seeking approval of sac-TMT for the treatment of adult patients with endometrial cancer who

have previously received platinum containing chemotherapy and a programmed death receptor

1 or programmed death ligand 1 inhibitor, separately or in combination, based on Phase 3

TroFuse-005 trial.

§ U.S.

FDA set Prescription Drug User Fee Act (PDUFA) date of June 15, 2027. The Company is

in discussions with the U.S. FDA and is hopeful for an earlier approval.

o In October, European Commission (EC) approved KEYTRUDA plus Padcev

as perioperative treatment for adults with resectable muscle-invasive bladder cancer (MIBC),

based on Phase 3 KEYNOTE-B15 trial.

5 Includes

the estimated income tax impacts on the reconciling items based on applying the statutory rate of the originating territory of the non-GAAP

adjustments for all periods presented. Amount in the third quarter of 2025 also includes $86 million of tax expense relating to audit

reserve adjustments.

- 8 -

o Ministry of Health, Labor and Welfare in Japan approved subcutaneous

pembrolizumab and berahyaluronidase alfa injection under the trademark KEYJECT (marketed

as KEYTRUDA QLEX in the U.S.) for all KEYTRUDA indications approved in Japan, based on Phase

3 MK-3475A-D77 trial.

o At the European Society for Medical Oncology (ESMO) Congress 2026

in October, positive new data were presented during three late-breaking Presidential Symposia

across three Phase 3 trials from the Company’s robust oncology pipeline and portfolio,

including:

§ Results

from Phase 3 TroFuse-005 trial evaluating sac-TMT for patients with advanced or recurrent

endometrial cancer previously treated with chemotherapy and anti-PD-1/L1 immunotherapy.

§ Results

from Phase 3 INTerpath-001 trial, in collaboration with Moderna, Inc. (Moderna), evaluating

adjuvant treatment with intismeran autogene (intismeran; V940 or mRNA-4157) in combination

with KEYTRUDA.

§ Results

from Phase 3 KEYNOTE-C93 trial evaluating KEYTRUDA monotherapy versus platinum doublet chemotherapy

as a first-line treatment for certain patients with mismatch repair deficient (dMMR) advanced

or recurrent endometrial cancer who had not previously received systemic chemotherapy or

who experienced recurrence more than six months after completing prior adjuvant therapy.

§ In

addition, data were presented from Phase 3 OptiTROP studies in China, led by Kelun-Biotech,

evaluating sac-TMT in non-small cell lung cancer (NSCLC), including:

· Results

from the OptiTROP-Lung06 study as first-line treatment for PD-L1-negative advanced non-squamous

NSCLC.

· Final

overall survival data from the OptiTROP-Lung04 study in epidermal growth factor receptor

(EGFR)-mutated NSCLC following progression on EGFR TKIs.

o Ifinatamab deruxtecan (I-DXd) Biologics License Application (BLA),

in collaboration with Daiichi Sankyo, for certain patients with previously treated extensive-stage

small cell lung cancer (ES-SCLC) was voluntarily withdrawn.

· Vaccines

and Infectious Diseases:

o U.S. FDA accepted a supplemental BLA (sBLA) for ENFLONSIA to expand

its indication to include prevention of respiratory syncytial virus (RSV) lower respiratory

tract disease (LRTD) in children under 2 years of age at increased risk for severe RSV disease

through their second RSV season, based on Phase 3 SMART trial.

§ U.S.

FDA set PDUFA date of March 22, 2027.

§ Applications

to expand marketing authorization for ENFLONSIA for same population in Europe and Japan,

based on Phase 3 SMART trial, have also been accepted.

- 9 -

o U.S. FDA accepted a supplemental New Drug Application (sNDA) for IDVYNSO

for the treatment of certain adults with HIV-1 infection who had not previously received

antiretroviral treatment, based on Phase 3 P053 trial. U.S. FDA also accepted an sNDA to

include 96-week data for IDVYNSO in certain virologically suppressed adults, based on the

Phase 3 P051 and P052 trials.

§ U.S.

FDA set a PDUFA date for both sNDAs of April 22, 2027.

· Cardiometabolic,

Respiratory and Specialty:

o U.S. FDA approved an update to U.S. product label for WINREVAIR to

include efficacy and safety data from the Phase 3 HYPERION trial evaluating adults recently

diagnosed with pulmonary arterial hypertension (PAH, World Health Organization [WHO] Group

1 pulmonary hypertension).

§ In

HYPERION, in patients diagnosed with PAH in the last 12 months, adding WINREVAIR on top of

background therapy reduced the risk of clinical worsening events compared to placebo.

· Immunology:

o Presented results from Phase 2b study of tulisokibart in adults with

moderate to severe hidradenitis suppurativa (HS).

· Ophthalmology:

o At the American Academy of Ophthalmology (AAO) 2026 Annual Meeting

in October, presented for the first time one-year results from Phase 2b/3 BRUNELLO trial

evaluating remigromig, an investigational, tetravalent, tri-specific antibody designed to

agonize the Wingless-related integration site (Wnt) pathway, in adults with diabetic macular

edema (DME).

· Business

Development:

o Announced an exclusive global license agreement with SciBrunch for

MK-2690 (SPR2015), an investigational preclinical oral KRAS G12D (ON) inhibitor.

Notable recent news releases on the Company’s

pipeline and portfolio are provided in the table that follows. Visit the News Releases section of the Company’s website to read

the releases.*

Oncology

Sac-TMT

Reduced Risk of Death by 32% and Risk of Disease Progression or Death by 41% Compared to Chemotherapy in Certain Patients With Advanced

or Recurrent Endometrial Cancer; Results From Phase 3 TroFuse-005 Trial

The

Company and Moderna Presented Results From Landmark Phase 3 INTerpath-001 Trial for Intismeran Plus KEYTRUDA at ESMO 2026 Presidential

Symposium; Intismeran Plus KEYTRUDA Significantly Reduced Risk of Recurrence or Death by 42% (HR=0.58 [95% CI, 0.45–0.75];

Two-Sided p<0.001) Compared to KEYTRUDA Alone for Patients With Completely Resected Stage IIB-IV Melanoma

KEYTRUDA

as Monotherapy Reduced Risk of Disease Progression or Death by 43% for Certain Patients With Advanced or Recurrent Endometrial Cancer

With dMMR Tumors Compared to Chemotherapy; Results From Phase 3 KEYNOTE-C93 Trial

U.S.

FDA Approved WELIREG Plus Lenvima for Certain Previously Treated Adult Patients With ccRCC; Based on Results From Phase 3 LITESPARK-011

Trial, Presented at ESMO

- 10 -

KEYTRUDA

QLEX Approved in Japan for Subcutaneous Administration for All KEYTRUDA Indications Approved in Japan; Based on Results From Phase

3 MK-3475A-D77 Trial

Approved KEYTRUDA Plus Padcev as Perioperative Treatment for Adults With Resectable MIBC; Based on Results From Phase 3 KEYNOTE-B15

Trial

I-DXd

BLA for Certain Patients With ES-SCLC Voluntarily Withdrawn

The

Company Entered Into Exclusive Global License Agreement With SciBrunch for SPR2015, an Investigational Oral KRAS G12D (ON) Inhibitor

Vaccines

and Infectious Diseases

U.S.

FDA Accepted sBLA for ENFLONSIA to Update Its RSV LRTD Indication to Include Children Under 2 Years at Increased Risk for Severe

RSV for Their Second Season; Based on Results From Phase 3 SMART Trial; FDA Set PDUFA Date of March 22, 2027

Cardiometabolic,

Respiratory and Specialty

U.S.

FDA Approved Update to the Label for WINREVAIR to Include Data From the Phase 3 HYPERION Trial Evaluating Adults Recently Diagnosed

With PAH (PAH, WHO Group 1 Pulmonary Hypertension)

Immunology

Tulisokibart

Met Primary and Key Secondary Endpoints in Phase 2b Study in Patients With Moderate to Severe HS

Ophthalmology

The

Company Presented One-Year Results From Pivotal Phase 2b/3 BRUNELLO Study Evaluating Remigromig, a Tri-Specific Agonist of the Wnt

Pathway, in Adults With DME, at AAO 2026

*References in the above news release titles have been modified for

the purpose of this announcement.

Sustainability Highlights

The Company’s 2025/2026 Purpose for Progress

Impact Report provided a comprehensive view of the Company’s measurable progress across its sustainability priorities, including

achieving all goals targeted for completion by 2025. The Company also introduced new targets for 2030, including a goal to reach

100 million people with access solutions that close gaps in care by 2030.

Full-Year 2026 Financial Outlook

The following table summarizes the Company’s

full-year financial outlook.

Full

Year 2026

Updated

Prior

Sales*

$66.8 billion to $67.3 billion

$66.3 billion to $67.3 billion

Non-GAAP

Gross margin3

Approximately 81%

Non-GAAP

Operating expenses3**

$42.4 billion to $42.9 billion

$42.0 billion to $42.7 billion

Non-GAAP

Other (income) expense, net3

Approximately $1.4 billion expense

Non-GAAP

Effective income tax rate3

32.0% to 33.0%

35.0% to 36.0%

Non-GAAP

EPS3***

$2.77 to $2.82

$2.66 to $2.76

Share count (assuming dilution)

Approximately 2.48 billion

*The Company does not have any non-GAAP adjustments

to sales.

**Includes one-time R&D charges of $9.0 billion

for the acquisition of Cidara Therapeutics, Inc. (Cidara), $5.7 billion for the acquisition of Terns Pharmaceuticals, Inc.

(Terns), and $400 million related to the global license agreement with SciBrunch. Outlook does not assume any additional significant

potential business development transactions.

***Includes one-time charges of $3.62 per share

for the acquisition of Cidara, $2.31 per share for the acquisition of Terns, and $0.12 per share related to the global license agreement

with SciBrunch.

The Company has not provided a reconciliation

of forward-looking non-GAAP gross margin, non-GAAP operating expenses, non-GAAP other (income) expense, net, non-GAAP effective income

tax rate and non-GAAP EPS to the most directly comparable GAAP measures, given it cannot predict with reasonable certainty the amounts

necessary for such a reconciliation, including intangible asset impairment charges, legal settlements, and income and losses from investments

in equity securities either owned directly or through ownership interests in investment funds, without unreasonable effort. These items

are inherently difficult to forecast and could have a significant impact on the Company’s future GAAP results.

- 11 -

The Company now anticipates full-year 2026 sales

to be between $66.8 billion and $67.3 billion, including a positive impact from foreign exchange of approximately 1% at mid-October 2026

exchange rates.

The Company now expects the full-year non-GAAP

effective income tax rate to be between 32.0% and 33.0%, including the impact of the non-tax-deductible one-time charges for the acquisitions

of Cidara and Terns.

The Company now expects full-year 2026 non-GAAP

EPS to be between $2.77 and $2.82, including a positive impact from foreign exchange of approximately $0.15 per share at mid-October 2026

exchange rates. This range includes one-time charges of $9.0 billion, or $3.62 per share, related to the acquisition of Cidara; $5.7

billion, or $2.31 per share, related to the acquisition of Terns; and $400 million, or $0.12 per share, related to the global license

agreement with SciBrunch. The charge related to SciBrunch was not previously included in the outlook. In 2025, non-GAAP EPS of $8.98

was negatively impacted by one-time charges of $0.20 per share in the aggregate related to certain business development transactions.

Consistent with past practice, the financial outlook

does not assume additional significant potential business development transactions.

Earnings Conference Call

Investors, journalists and the general public

may access a live audio webcast of the call on Thursday, Oct. 29, at 9 a.m. EDT via this weblink. A replay of the webcast,

along with the sales and earnings news release, supplemental financial disclosures and slides highlighting the results, will be available

on the Company’s website.

All participants may join the call by dialing

(800) 369-3351 (U.S. and Canada Toll-Free) or (517) 308-9448 and using the access code 9818590.

About Our Company

At Merck & Co., Inc., Rahway, N.J.,

USA, known as MSD outside of the United States and Canada, we are unified around our purpose: We use the power of leading-edge science

to save and improve lives around the world. For more than 130 years, we have brought hope to humanity through the development of important

medicines and vaccines. We aspire to be the premier research-intensive biopharmaceutical company in the world – and today, we are

at the forefront of research to deliver innovative health solutions that advance the prevention and treatment of diseases in people and

animals. We foster a diverse and inclusive global workforce and operate responsibly every day to enable a safe, sustainable and healthy

future for all people and communities.

- 12 -

Forward-Looking Statement of Merck & Co., Inc., Rahway,

N.J., USA

This news release of Merck & Co., Inc.,

Rahway, 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 candidates that the candidates 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 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 Annual

Report on Form 10-K for the year ended December 31, 2025 and the Company’s other filings with the Securities and Exchange

Commission (SEC) available at the SEC’s Internet site (www.sec.gov).

Appendix

Generic product names are provided below.

Pharmaceutical

BRIDION (sugammadex)

CAPVAXIVE (Pneumococcal 21-valent Conjugate Vaccine)

ENFLONSIA (clesrovimab-cfor)

GARDASIL (Human Papillomavirus Quadrivalent [Types

6, 11, 16 and 18] Vaccine, Recombinant)

GARDASIL 9 (Human Papillomavirus 9-valent Vaccine, Recombinant)

IDVYNSO (doravirine/islatravir)

JANUMET (sitagliptin and metformin HCl)

JANUVIA (sitagliptin)

KEYTRUDA (pembrolizumab)

KEYTRUDA QLEX (pembrolizumab and berahyaluronidase alfa-pmph)

- 13 -

LAGEVRIO (molnupiravir)

Lenvima (lenvatinib)

Lynparza (olaparib)

M-M-R II (Measles, Mumps and Rubella Virus Vaccine Live)

OHTUVAYRE (ensifentrine)

PREVYMIS (letermovir)

PROQUAD (Measles, Mumps, Rubella and Varicella Virus Vaccine Live)

VARIVAX (Varicella Virus Vaccine Live)

WELIREG (belzutifan)

WINREVAIR (sotatercept-csrk)

Animal Health

BRAVECTO (fluralaner)

###

Media Contacts:

Investor Contacts:

Michael Levey

michael.levey@msd.com

John Cummins

john.cummins2@msd.com

Peter Dannenbaum

(732) 594-1579

Steven Graziano

(732) 594-1583

MERCK

& CO., INC., RAHWAY, N.J., USA

CONSOLIDATED

STATEMENT OF OPERATIONS - GAAP

(AMOUNTS

IN MILLIONS, EXCEPT PER SHARE FIGURES)

(UNAUDITED)

Table

GAAP

3Q26

3Q25

Change

Sep

YTD

2026

Sep

YTD

2025

Change

Sales

$ 18,085

$ 17,276

5 %

$ 50,978

$ 48,611

5 %

Costs, Expenses and Other

Cost of sales

4,892

3,855

27 %

13,482

10,831

24 %

Selling, general and administrative

2,886

2,633

10 %

8,491

7,835

8 %

Research and development

4,537

4,234

7 %

26,871

11,903

Restructuring costs

184

530

676

-22 %

Other (income) expense, net

(238 )

262

(281 )

Income Before Taxes

5,559

6,745

-18 %

1,342

17,647

-92 %

Income Tax Provision

492

958

1,855

2,346

Net Income (Loss)

5,067

5,787

-12 %

(513 )

15,301

Less: Net Income (Loss) Attributable to Noncontrolling Interests

(3 )

Net Income (Loss) Attributable to Merck & Co., Inc., Rahway, N.J., USA

$ 5,065

$ 5,785

-12 %

$ (510 )

$ 15,291

Earnings (Loss) per Common Share Assuming Dilution (1)

$ 2.04

$ 2.32

-12 %

$ (0.21 )

$ 6.08

Average Shares Outstanding Assuming Dilution (1)

2,478

2,498

2,471

2,514

Effective Income Tax Rate

8.9 %

14.2 %

138.2 %

13.3 %

* 100% or greater

(1)

Because the Company recorded a net loss in the first nine months of 2026, no potential dilutive common shares were used in the computation

of loss per common share assuming dilution as the effect would have been anti-dilutive.

MERCK

& CO., INC., RAHWAY, N.J., USA

THREE

AND NINE MONTHS ENDED SEPTEMBER 30, 2026 GAAP TO NON-GAAP RECONCILIATION

(AMOUNTS

IN MILLIONS, EXCEPT PER SHARE FIGURES)

(UNAUDITED)

Table

GAAP

Acquisition-

and

Divestiture-Related Costs(1)

Restructuring

Costs(2)

(Income)

Loss from

Investments in

Equity Securities

Adjustment

Subtotal

Non-GAAP

Third

Quarter

Cost

of sales

$ 4,892

1,140

396

1,536

$ 3,356

Selling,

general and administrative

2,886

2,862

Research

and development

4,537

4,533

Restructuring

costs

184

–

Other

(income) expense, net

(393 )

420

Income

Before Taxes

5,559

(1,167 )

(581 )

393

(1,355 )

6,914

Income

Tax Provision (Benefit)

492

(239 )(3)

(105 )(3)

83 (3)

(261 )

753

Net

Income

5,067

(928 )

(476 )

310

(1,094 )

6,161

Net

Income Attributable to Merck & Co., Inc., Rahway, N.J., USA

5,065

(928 )

(476 )

310

(1,094 )

6,159

Earnings

per Common Share Assuming Dilution

$ 2.04

(0.38 )

(0.19 )

0.12

(0.45 )

$ 2.49

Effective

Income Tax Rate

8.9 %

10.9 %

September

YTD

Cost

of sales

$ 13,482

3,221

817

4,038

$ 9,444

Selling,

general and administrative

8,491

8,418

Research

and development

26,871

26,828

Restructuring

costs

530

–

Other

(income) expense, net

262

(764 )

1,026

Income

Before Taxes

1,342

(3,303 )

(1,381 )

764

(3,920 )

5,262

Income

Tax Provision (Benefit)

1,855

(660 )(3)

(240 )(3)

163 (3)

(737 )

2,592

Net

(Loss) Income

(513 )

(2,643 )

(1,141 )

601

(3,183 )

2,670

Net

(Loss) Income Attributable to Merck & Co., Inc., Rahway, N.J., USA

(510 )

(2,643 )

(1,141 )

601

(3,183 )

2,673

(Loss)

Earnings per Common Share Assuming Dilution (4)

$ (0.21 )

(1.07 )

(0.46 )

0.24

(1.29 )

$ 1.08

Effective

Income Tax Rate

138.2 %

49.3 %

Only the line items that are affected by non-GAAP adjustments

are shown.

The Company is providing certain non-GAAP information that

excludes certain items because of the nature of these items and the impact they have on the analysis of underlying business performance

and trends. Management believes that providing non-GAAP information enhances investors’ understanding of the Company’s

results because management uses non-GAAP measures to assess performance. Management uses non-GAAP measures internally for planning

and forecasting purposes and to measure the performance of the Company along with other metrics. In addition, annual employee compensation,

including senior management’s compensation, is derived in part using a non-GAAP pretax income metric. The non-GAAP information

presented should be considered in addition to, but not as a substitute for or superior to, information prepared in accordance with

GAAP.

(1)

Amounts included in cost of sales reflect expenses for the amortization of intangible assets, as well as the recognition of fair

value step-up of inventories related to the 2025 Verona Pharma plc acquisition. Amounts included in selling, general and administrative

expenses reflect integration, transaction and certain other costs related to acquisitions and divestitures.

(2)

Amounts primarily include employee separation costs, accelerated depreciation and asset impairment charges associated with facilities

to be closed or divested, as well as contractual termination costs, related to activities under the Company's formal restructuring

programs.

(3)

Represents the estimated tax impacts on the reconciling items based on applying the statutory rate of the originating territory of

the non-GAAP adjustments.

(4)

Because the Company recorded a net loss in the first nine months of 2026, no potential dilutive common shares were used in the computation

of loss per common share assuming dilution as the effect would have been anti-dilutive.

MERCK & CO., INC.,

RAHWAY, N.J., USA

FRANCHISE / KEY PRODUCT SALES

(AMOUNTS IN MILLIONS)

(UNAUDITED)

Table 3

2026

2025

Sep

YTD

Sep

YTD

Sep

YTD

Full

Year

Nom

Ex-Exch

Nom

Ex-Exch

TOTAL

SALES (1)

$ 16,286

$ 16,607

$ 18,085

$ 50,978

$ 15,529

$ 15,806

$ 17,276

$ 48,611

$ 16,400

$ 65,011

PHARMACEUTICAL

14,349

14,760

16,268

45,377

13,638

14,050

15,611

43,299

14,843

58,142

Oncology

Keytruda

7,906

7,904

7,771

23,581

7,205

7,956

8,142

23,303

8,337

31,641

-5

-4

Keytruda

Qlex

128

463

830

1,420

Alliance

Revenue – Lynparza (2)

341

365

352

1,059

312

370

379

1,061

389

1,450

-7

-2

Alliance

Revenue – Lenvima (2)

256

283

287

826

258

265

258

781

272

1,053

Welireg

199

271

307

776

137

162

196

496

220

716

Alliance

Revenue – Reblozyl (3)

148

122

177

448

119

107

136

361

164

525

Vaccines

& Infectious Diseases

Gardasil/Gardasil

1,069

1,169

1,995

4,232

1,327

1,126

1,749

4,202

1,031

5,233

ProQuad/M-M-R

II/Varivax

538

592

730

1,860

539

609

684

1,832

619

2,451

Bridion

472

497

144

1,113

441

461

439

1,341

499

1,841

-67

-17

Prevymis

272

295

347

915

208

228

266

702

275

978

Capvaxive

142

184

263

588

107

129

244

480

279

759

Vaxneuvance

202

148

195

545

230

229

226

685

140

825

-14

-13

-20

-22

RotaTeq

206

134

196

536

228

121

204

554

119

673

-4

-3

-4

Zerbaxa

249

225

312

Delstrigo

101

243

228

306

-13

-12

Enflonsia

187

190

100

138

136

142

140

Isentress/Isentress

171

258

325

-36

-34

Dificid

222

247

-68

Lagevrio

102

138

323

380

-88

-85

Cardiometabolic,

Respiratory, & Specialty

Winrevair

525

588

694

1,808

280

336

360

976

467

1,443

Januvia

367

258

186

811

549

372

382

1,302

302

1,604

-51

-50

-38

-37

Janumet

207

171

194

572

247

251

243

741

199

940

-20

-23

-24

Ohtuvayre

131

204

184

519

178

Alliance

Revenue - Adempas/Verquvo (4)

109

126

118

353

106

123

112

340

129

470

Adempas

(5)

234

229

312

-5

-3

-1

Other

Pharmaceutical (6)

774

641

793

2,209

865

703

1,004

2,573

770

3,340

-21

-14

-15

ANIMAL

HEALTH

1,791

1,775

1,676

5,243

1,588

1,646

1,615

4,849

1,505

6,354

Livestock

1,064

1,041

1,048

3,154

924

961

1,023

2,909

987

3,896

Companion

Animal

727

734

628

2,089

664

685

592

1,940

518

2,458

Other

Revenues (7)

146

141

358

303

110

463

515

185

-25

-23

-8

*200%

or greater

Sum

of quarterly amounts may not equal year-to-date amounts due to rounding.

(1) Only select products are shown.

(2)

Alliance Revenue represents the Company's share of profits, which are product sales net of cost of sales and commercialization

costs.

(3) Alliance Revenue represents royalties.

(4) Alliance Revenue represents the Company's share of profits from sales in Bayer's marketing territories, which are product sales net of cost of sales and commercialization costs.

(5) Net product sales in the Company's marketing territories.

(6) Includes Pharmaceutical products not individually shown above. Also reflects total alliance revenue for Koselugo of $161 million, $10 million and $13 million in the first, second and third quarter of 2026, respectively, and $44 million, $43 million and $214 million in the first, second and third quarter of 2025, respectively.

(7) Other Revenues are comprised primarily of revenues from third-party manufacturing arrangements and miscellaneous corporate revenues, including revenue-hedging activities. Other Revenues related to the receipt of milestone payments for out-licensed products were $132 million, $0 million and $2 million in the first, second and third quarter of 2026, respectively, and $95 million, $5 million and $11 million in the first, second and third quarter of 2025, respectively.

EX-99.2 — EXHIBIT 99.2

EX-99.2

Filename: tm2628203d1_ex99-2.htm · Sequence: 3

Exhibit 99.2

MERCK

& CO., INC., RAHWAY, N.J., USA

CONSOLIDATED

STATEMENT OF OPERATIONS - GAAP

(AMOUNTS

IN MILLIONS, EXCEPT PER SHARE FIGURES)

(UNAUDITED)

Table

2026

2025

% Change

Sep YTD

Full Year

Sep YTD

Sales

$ 16,286

$ 16,607

$ 18,085

$ 50,978

$ 15,529

$ 15,806

$ 17,276

$ 48,611

$ 16,400

$ 65,011

5 %

Costs, Expenses and Other

Cost of sales

4,195

4,395

4,892

13,482

3,419

3,557

3,855

10,831

5,551

16,382

27 %

24 %

Selling, general and administrative

2,700

2,904

2,886

8,491

2,552

2,649

2,633

7,835

2,898

10,733

10 %

8 %

Research and development

12,592

9,741

4,537

26,871

3,621

4,048

4,234

11,903

3,886

15,789

7 %

Restructuring costs

195

151

184

530

560

676

213

889

-22 %

Other (income) expense, net

138

262

(35 )

(7 )

(238 )

(281 )

432

151

(Loss) Income Before Taxes

(3,534 )

(683 )

5,559

1,342

5,903

4,999

6,745

17,647

3,420

21,067

-18 %

-92 %

Income Tax Provision

709

654

492

1,855

818

571

958

2,346

458

2,804

Net (Loss) Income

(4,243 )

(1,337 )

5,067

(513 )

5,085

4,428

5,787

15,301

2,962

18,263

-12 %

Less: Net (Loss) Income Attributable to Noncontrolling Interests

(3 )

(2 )

(3 )

(1 )

Net (Loss) Income Attributable to Merck & Co., Inc., Rahway, N.J., USA

$ (4,240 )

$ (1,335 )

$ 5,065

$ (510 )

$ 5,079

$ 4,427

$ 5,785

$ 15,291

$ 2,963

$ 18,254

-12 %

(Loss) Earnings per Common Share Assuming Dilution (1)

$ (1.72 )

$ (0.54 )

$ 2.04

$ (0.21 )

$ 2.01

$ 1.76

$ 2.32

$ 6.08

$ 1.19

$ 7.28

-12 %

Average Shares Outstanding Assuming Dilution (1)

2,472

2,470

2,478

2,471

2,531

2,513

2,498

2,514

2,488

2,507

Effective Income Tax Rate

-20.1 %

-95.9 %

8.9 %

138.2 %

13.9 %

11.4 %

14.2 %

13.3 %

13.4 %

13.3 %

* 100% or greater

Sum of quarterly amounts may not equal year-to-date amounts due to rounding.

(1)

Because the Company recorded a net loss in the first and second quarters of 2026, as well as the first nine months of 2026, no potential

dilutive common shares were used in the computations of loss per common share assuming dilution as the effects would have been anti-dilutive.

MERCK & CO., INC.,

RAHWAY, N.J., USA

THREE AND NINE MONTHS

ENDED SEPTEMBER 30, 2025 GAAP TO NON-GAAP RECONCILIATION

(AMOUNTS IN MILLIONS,

EXCEPT PER SHARE FIGURES)

(UNAUDITED)

Table 2b

GAAP

Acquisition-

and

Divestiture-Related

Costs (1)

Restructuring

Costs (2)

(Income)

Loss

from

Investments

in Equity

Securities

Certain

Other

Items

Adjustment

Subtotal

Non-GAAP

Third

Quarter

Cost of sales

$ 3,855

621

110

731

$ 3,124

Selling, general and administrative

2,633

2,599

Research and development

4,234

233

237

3,997

Restructuring costs

–

Other (income) expense, net

(238 )

(344 )

106

Income Before Taxes

6,745

(659 )

(390 )

344

(705 )

7,450

Income Tax Provision (Benefit)

958

(119 )(3)

(82 )(3)

73  (3)

86 (4)

(42 )

1,000

Net Income

5,787

(540 )

(308 )

271

(86 )

(663 )

6,450

Net Income Attributable to Merck

& Co., Inc., Rahway, N.J., USA

5,785

(540 )

(308 )

271

(86 )

(663 )

6,448

Earnings

per Common Share Assuming Dilution

$ 2.32

(0.22 )

(0.12 )

0.11

(0.03 )

(0.26 )

$ 2.58

Effective

Income Tax Rate

14.2 %

13.4 %

September YTD

Cost of sales

$ 10,831

1,817

311

2,128

$ 8,703

Selling, general and administrative

7,835

7,762

Research and development

11,903

286

300

11,603

Restructuring costs

676

–

Other (income) expense, net

(281 )

(3 )

(512 )

(515 )

234

Income Before Taxes

17,647

(1,900 )

(1,274 )

512

(2,662 )

20,309

Income Tax Provision (Benefit)

2,346

(338 )(3)

(239 )(3)

109  (3)

(60 )(4)

(528 )

2,874

Net Income

15,301

(1,562 )

(1,035 )

403

(2,134 )

17,435

Net Income Attributable to Merck

& Co., Inc., Rahway, N.J., USA

15,291

(1,562 )

(1,035 )

403

(2,134 )

17,425

Earnings

per Common Share Assuming Dilution

$ 6.08

(0.62 )

(0.41 )

0.16

0.02

(0.85 )

$ 6.93

Effective

Income Tax Rate

13.3 %

14.2 %

Only

the line items that are affected by non-GAAP adjustments are shown.

The Company is providing certain non-GAAP information that excludes

certain items because of the nature of these items and the impact they have on the analysis of underlying business performance and trends.

Management believes that providing non-GAAP information enhances investors’ understanding of the Company’s results because

management uses non-GAAP measures to assess performance. Management uses non-GAAP measures internally for planning and forecasting purposes

and to measure the performance of the Company along with other metrics. In addition, annual employee compensation, including senior management’s

compensation, is derived in part using a non-GAAP pretax income metric. The non-GAAP information presented should be considered in addition

to, but not as a substitute for or superior to, information prepared in accordance with GAAP.

(1) Amounts included in cost of sales for the third quarter reflect expenses for the amortization of intangible assets. Amounts included in cost of sales for the nine-month period include the amortization of intangible assets and intangible asset impairment charges, partially offset by a decrease in the estimated fair value measurement of liabilities for contingent consideration. Amounts included in selling, general and administrative expenses reflect integration, transaction and certain other costs related to acquisitions and divestitures. Amounts included in research and development expenses reflect the amortization of intangible assets.

(2) Amounts primarily include employee separation costs, accelerated depreciation and asset impairment charges associated with facilities to be closed or divested, as well as contractual termination costs, related to activities under the Company's formal restructuring programs.

(3) Represents the estimated tax impacts on the reconciling items based on applying the statutory rate of the originating territory of the non-GAAP adjustments.

(4) Amount in the third quarter represents tax expense relating to audit reserve adjustments. Amount in the nine-month period represents a tax benefit, including a net benefit related to favorable audit reserve adjustments.

MERCK & CO., INC.,

RAHWAY, N.J., USA

FRANCHISE / KEY PRODUCT SALES

THIRD QUARTER 2026

(AMOUNTS IN MILLIONS)

(UNAUDITED)

Table 3a

Global

U.S.

International

2026

2025

Change

2026

2025

Change

2026

2025

Change

TOTAL

SALES (1)

$ 18,085

$ 17,276

$ 10,615

$ 10,012

$ 7,471

$ 7,264

PHARMACEUTICAL

16,268

15,611

10,119

9,493

6,149

6,118

Oncology

Keytruda

7,771

8,142

-5

4,520

4,879

-7

3,251

3,263

Keytruda

Qlex

830

693

136

Alliance

Revenue – Lynparza (2)

352

379

-7

171

184

-7

182

195

-7

Welireg

307

196

237

161

Alliance

Revenue – Lenvima (2)

287

258

204

177

Alliance

Revenue – Reblozyl (3)

177

136

145

111

Vaccines

& Infectious Diseases

Gardasil/Gardasil

1,995

1,749

1,366

1,154

629

595

ProQuad/M-M-R

II/Varivax

730

684

561

554

169

130

Prevymis

347

266

189

128

158

138

Capvaxive

263

244

207

238

-13

RotaTeq

196

204

-4

150

141

-28

Vaxneuvance

195

226

-14

111

134

-18

-7

Enflonsia

187

138

141

Bridion

144

439

-67

108

392

-72

-24

Zerbaxa

Delstrigo

-13

-3

-15

Isentress/Isentress

-36

-31

-43

Lagevrio

138

-88

-71

114

-91

Dificid

-68

-78

-44

Cardiometabolic,

Respiratory, & Specialty

Winrevair

694

360

610

335

Janumet

194

243

-20

-22

133

165

-19

Januvia

186

382

-51

258

-70

108

124

-12

Ohtuvayre

184

Alliance

Revenue - Adempas/Verquvo (4)

118

112

108

103

Adempas

(5)

-5

Other

Pharmaceutical (6)

793

1,004

-21

161

223

-28

633

784

-19

ANIMAL

HEALTH

1,676

1,615

493

504

-2

1,184

1,112

Livestock

1,048

1,023

199

213

-7

850

811

Companion

Animal

628

592

294

291

334

301

Other

Revenues (7)

141

185

-80

138

*200% or greater

Sum of U.S. plus international may not equal global due to rounding.

(1) Only select products are shown.

(2) Alliance Revenue represents the Company's share of profits, which are product sales net of cost of sales and commercialization costs.

(3) Alliance Revenue represents royalties.

(4) Alliance Revenue represents the Company's share of profits from sales in Bayer's marketing territories, which are product sales net of cost of sales and commercialization costs.

(5) Net product sales in the Company's marketing territories.

(6) Includes Pharmaceutical products not individually shown above. Also reflects total alliance revenue for Koselugo of $13 million and $214 million on a global basis in the third quarter of 2026 and 2025, respectively.

(7) Other Revenues are comprised primarily of revenues from third-party manufacturing arrangements and miscellaneous corporate revenues, including revenue-hedging activities. Other Revenues related to the receipt of milestone payments for out-licensed products were $2 million and $11 million on a global basis in the third quarter of 2026 and 2025, respectively.

MERCK & CO., INC.,

RAHWAY, N.J., USA

FRANCHISE / KEY PRODUCT SALES

SEPTEMBER YEAR-TO-DATE 2026

(AMOUNTS IN MILLIONS)

(UNAUDITED)

Table 3b

Global

U.S.

International

Sep

YTD

2026

Sep

YTD

2025

Change

Sep

YTD

2026

Sep

YTD

2025

Change

Sep

YTD

2026

Sep

YTD

2025

Change

TOTAL

SALES (1)

$ 50,978

$ 48,611

$ 29,146

$ 27,371

$ 21,832

$ 21,240

PHARMACEUTICAL

45,377

43,299

27,457

25,747

17,920

17,552

Oncology

Keytruda

23,581

23,303

13,731

13,936

-1

9,851

9,367

Keytruda

Qlex

1,420

1,195

225

Alliance

Revenue – Lynparza (2)

1,059

1,061

486

503

-3

573

558

Alliance

Revenue – Lenvima (2)

826

781

573

545

253

236

Welireg

776

496

603

422

173

133

Alliance

Revenue – Reblozyl (3)

448

361

370

299

Vaccines

& Infectious Diseases

Gardasil/Gardasil

4,232

4,202

2,392

2,235

1,840

1,967

-6

ProQuad/M-M-R

II/Varivax

1,860

1,832

1,409

1,457

-3

452

374

Bridion

1,113

1,341

-17

995

1,181

-16

118

161

-26

Prevymis

915

702

472

345

443

357

Capvaxive

588

480

464

473

-2

124

Vaxneuvance

545

685

-20

303

409

-26

243

276

-12

RotaTeq

536

554

-3

399

366

137

187

-27

Zerbaxa

249

225

151

136

Delstrigo

243

228

-15

208

185

Enflonsia

190

142

140

Isentress/Isentress

171

258

-34

101

144

-29

114

-39

Dificid

222

-68

185

-78

-22

Lagevrio

323

-85

-73

233

-89

Cardiometabolic,

Respiratory, & Specialty

Winrevair

1,808

976

1,609

926

198

Januvia

811

1,302

-38

479

819

-42

333

483

-31

Janumet

572

741

-23

156

210

-26

416

530

-22

Ohtuvayre

519

518

Alliance

Revenue - Adempas/Verquvo (4)

353

340

329

308

-24

Adempas

(5)

234

229

234

229

Other

Pharmaceutical (6)

2,209

2,573

-14

479

633

-24

1,725

1,944

-11

ANIMAL

HEALTH

5,243

4,849

1,547

1,505

3,696

3,345

Livestock

3,154

2,909

613

598

2,541

2,312

Companion

Animal

2,089

1,940

934

907

1,155

1,033

Other

Revenues (7)

358

463

-23

142

119

216

343

-37

*200% or greater

Sum of U.S. plus international may not equal global due to rounding.

(1) Only select products are shown.

(2) Alliance Revenue represents the Company's share of profits, which are product sales net of cost of sales and commercialization costs.

(3) Alliance Revenue represents royalties.

(4) Alliance Revenue represents the Company's share of profits from sales in Bayer's marketing territories, which are product sales net of cost of sales and commercialization costs.

(5) Net product sales in the Company's marketing territories.

(6) Includes Pharmaceutical products not individually shown above. Also reflects total alliance revenue for Koselugo of $183 million and $301 million on a global basis for September YTD 2026 and 2025, respectively.

(7) Other Revenues are comprised primarily of revenues from third-party manufacturing arrangements and miscellaneous corporate revenues, including revenue-hedging activities. Other Revenues related to the receipt of milestone payments for out-licensed products were $133 million and $111 million on a global basis for September YTD 2026 and 2025, respectively.

MERCK & CO., INC.,

RAHWAY, N.J., USA

PHARMACEUTICAL GEOGRAPHIC SALES

(AMOUNTS IN MILLIONS)

(UNAUDITED)

Table 3c

2026

2025

Change

Sep

YTD

Sep

YTD

Full

Year

Sep

YTD

TOTAL

PHARMACEUTICAL

$ 14,349

$ 14,760

$ 16,268

$ 45,377

$ 13,638

$ 14,050

$ 15,611

$ 43,299

$ 14,843

$ 58,142

United

States

8,512

8,827

10,119

27,457

7,927

8,328

9,493

25,747

8,662

34,409

% Pharmaceutical

Sales

59.3 %

59.8 %

62.2 %

60.5 %

58.1 %

59.3 %

60.8 %

59.5 %

58.4 %

59.2 %

Europe

(1)

2,725

2,801

2,837

8,363

2,384

2,551

2,675

7,610

2,839

10,449

% Pharmaceutical

Sales

19.0 %

17.4 %

18.4 %

17.5 %

18.2 %

17.1 %

17.6 %

19.1 %

18.0 %

Latin

America

624

636

730

1,990

589

654

691

1,933

644

2,578

% Pharmaceutical

Sales

4.3 %

4.5 %

4.4 %

4.3 %

4.7 %

4.4 %

4.5 %

4.3 %

4.4 %

Asia

Pacific (other than China and Japan)

569

636

596

1,800

535

609

593

1,736

586

2,323

% Pharmaceutical

Sales

4.0 %

4.3 %

3.7 %

4.0 %

3.9 %

4.3 %

3.8 %

4.0 %

Japan

535

558

569

1,662

651

604

693

1,948

684

2,632

-18

-15

% Pharmaceutical

Sales

3.7 %

3.8 %

3.5 %

3.7 %

4.8 %

4.3 %

4.4 %

4.5 %

4.6 %

4.5 %

Eastern

Europe/Middle East/Africa

413

408

399

1,220

435

451

365

1,250

348

1,598

-2

% Pharmaceutical

Sales

2.9 %

2.8 %

2.5 %

2.7 %

3.2 %

2.3 %

2.9 %

2.3 %

2.7 %

China

353

368

429

1,151

668

407

377

1,452

364

1,816

-21

% Pharmaceutical

Sales

2.5 %

2.6 %

2.5 %

4.9 %

2.9 %

2.4 %

3.4 %

2.5 %

3.1 %

Canada

137

154

152

443

125

135

134

394

153

547

% Pharmaceutical

Sales

1.0 %

0.9 %

1.0 %

0.9 %

1.0 %

0.9 %

1.0 %

0.9 %

Other

481

372

437

1,291

324

311

590

1,229

563

1,790

-26

Pharmaceutical Sales

3.3 %

2.5 %

2.7 %

2.8 %

2.4 %

2.1 %

3.9 %

2.7 %

3.8 %

3.2 %

Sum

of quarterly amounts may not equal year-to-date amounts due to rounding.

(1) Europe represents all European Union countries, the European Union accession markets and the United Kingdom.

MERCK

& CO., INC., RAHWAY, N.J., USA

OTHER

(INCOME) EXPENSE, NET - GAAP

(AMOUNTS

IN MILLIONS)

(UNAUDITED)

Table

3Q26

3Q25

Sep YTD

2026

Sep YTD

2025

Interest income

$ (52 )

$ (96 )

$ (122 )

$ (274 )

Interest expense

546

327

1,550

946

Exchange losses

138

224

Income from investments in equity securities, net (1)

(401 )

(373 )

(811 )

(563 )

Net periodic defined benefit plan (credit) cost other than service cost

(120 )

(152 )

(382 )

(452 )

Other, net

(9 )

(111 )

(162 )

Total

$ 27

$ (238 )

$ 262

$ (281 )

(1)

Includes net realized and unrealized gains and losses from investments in equity securities either owned directly or through ownership

interests in investment funds. Unrealized gains and losses from investments that are directly owned are determined at the end of the

reporting period, while gains and losses from ownership interests in investment funds are accounted for on a one quarter lag.

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- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as written communications pursuant to Rule 425 under the Securities Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Securities Act

-Number 230

-Section 425

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