Merck & Co. · Earnings release · 8-K Exhibit 99

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

CONSOLIDATED

STATEMENT OF INCOME - GAAP

(AMOUNTS

IN MILLIONS, EXCEPT PER SHARE FIGURES)

(UNAUDITED)

Table

1a

% Change

1Q

2Q

3Q

4Q

Full Year

1Q

2Q

3Q

4Q

Full Year

4Q

Full Year

Sales

$

$

$

$

$

$

$

$

$

$

5

%

1

%

Costs, Expenses and Other

Cost of sales

%

8

%

Selling, general and administrative

1

%

-1

%

Research and development

%

%

Restructuring costs

*

*

Other (income) expense, net

)

(7

)

)

)

)

)

*

*

Income Before Taxes

%

6

%

Income Tax Provision

Net Income

%

7

%

Less: Net Income (Loss) Attributable to Noncontrolling Interests

6

1

2

(1

)

9

5

6

4

2

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

$

$

$

$

$

$

$

$

$

$

%

7

%

Earnings per Common Share Assuming Dilution

$

$

$

$

$

$

$

$

$

$

%

8

%

Average Shares Outstanding Assuming Dilution

Tax Rate

%

%

%

%

%

%

%

%

%

%

*

Sum

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

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

FOURTH QUARTER AND FULL YEAR 2024 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

Fourth Quarter

Cost of sales

$

$

Selling, general and administrative

Research and development

(1

)

Restructuring costs

–

Other (income) expense, net

)

5

Income Before Taxes

)

)

)

)

Income Tax Provision (Benefit)

)(3)

)(3)

)(3)

)(4)

)

Net Income

)

)

)

)

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

)

)

)

)

Earnings per Common Share Assuming Dilution

$

)

)

)

)

$

Tax Rate

%

%

Full Year

Cost of sales

$

$

Selling, general and administrative

Research and development

1

Restructuring costs

–

Other (income) expense, net

)

)

)

Income Before Taxes

)

)

)

)

Income Tax Provision (Benefit)

)(3)

)(3)

)(3)

)(4)

)

Net Income

)

)

)

)

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

)

)

)

)

Earnings per Common Share Assuming Dilution

$

)

)

)

)

$

Tax Rate

%

%

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

Merck 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 primarily reflect expenses for the amortization of intangible assets. 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 primarily reflect the amortization of intangible assets. Additionally, research

and development expenses for the full year includes Animal Health intangible asset impairment charges. Amounts included in other (income)

expense, net, primarily reflect royalty income and a decrease in the estimated fair value measurement of liabilities for contingent consideration

related to the prior termination of the Sanofi-Pasteur MSD joint venture.

(2) Amounts primarily include employee separation

costs, accelerated depreciation and asset impairment charges associated with facilities to be closed or divested 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)Represents benefits recorded in the fourth quarter and full year due to reductions in reserves for unrecognized income tax benefits resulting

from the expiration of the statute of limitations for assessments related to federal income tax return years. The benefit recognized

in the fourth quarter relates to the 2020 federal tax return year and the benefit recognized for the full year relates to both the 2020

and 2019 federal tax return years.

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

FRANCHISE / KEY PRODUCT SALES

(AMOUNTS IN MILLIONS)

(UNAUDITED)

Table 3a

Global

U.S.

International

% Change

% Change

% Change

TOTAL SALES (1)

$

$

5

$

$

$

$

-2

PHARMACEUTICAL

6

-2

Oncology

Keytruda

6

1

Keytruda Qlex

-

-

2

-

Alliance Revenue – Lynparza (2)

7

1

Alliance Revenue – Lenvima (2)

7

5

Welireg

Alliance Revenue – Reblozyl (3)

Vaccines(4)

Gardasil/Gardasil 9

7

ProQuad/M-M-R II/Varivax

4

2

9

Capvaxive

*

*

0

*

Vaxneuvance

-6

RotaTeq

8

8

Hospital Acute Care

Bridion

Prevymis

Zerbaxa

Dificid

8

7

Cardiometabolic & Respiratory

Winrevair

9

*

Ohtuvayre

-

-

Alliance Revenue - Adempas/Verquvo (5)

7

5

*

Adempas(6)

Virology

Delstrigo

-1

Isentress/Isentress HD

-3

Lagevrio

Pifeltro

6

-3

Neuroscience

Belsomra

8

1

Diabetes(7)

Januvia

*

Janumet

Other Pharmaceutical (8)

-6

4

-9

ANIMAL HEALTH

8

1

Livestock

3

Companion Animal

2

-1

4

Other Revenues (9)

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) Total Vaccines sales were $2,364 million and $2,693 million on a global basis in the fourth quarter of 2025 and 2024, respectively.

(5) 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.

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

(7) Total Diabetes sales were $579 million and $546 million on a global basis in the fourth quarter of 2025 and 2024, respectively.

(8) Includes Pharmaceutical products not individually shown above. Also reflects total alliance revenue for Koselugo of $135 million and $56 million on a global basis in the fourth quarter of 2025 and 2024, respectively.

(9) 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 upfront and milestone payments for out-licensed products were $27 million and $15 million in the fourth quarter of 2025 and 2024, respectively.

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

FRANCHISE / KEY PRODUCT SALES

(AMOUNTS IN MILLIONS)

(UNAUDITED)

Table 3b

Global

U.S.

International

% Change

% Change

% Change

TOTAL SALES (1)

$

$

1

$

$

$

$

PHARMACEUTICAL

1

Oncology

Keytruda

7

5

Keytruda Qlex

-

-

2

-

Alliance Revenue – Lynparza (2)

9

Alliance Revenue – Lenvima (2)

4

4

4

Welireg

Alliance Revenue – Reblozyl (3)

Vaccines(4)

T1Gardasil/Gardasil 9

9

ProQuad/M-M-R II/Varivax

-1

-2

0

Vaxneuvance

2

0

5

Capvaxive

*

*

1

*

RotaTeq

-5

3

Hospital Acute Care

Bridion

4

Prevymis

Zerbaxa

Dificid

Cardiometabolic & Respiratory

Winrevair

*

*

*

Alliance Revenue - Adempas/Verquvo (5)

8

Adempas(6)

9

9

Ohtuvayre

-

-

Virology

Lagevrio

Isentress/Isentress HD

-3

Delstrigo

1

Pifeltro

5

-1

Neuroscience

Belsomra

Immunology

Simponi

Remicade

Diabetes(7)

Januvia

Janumet

1

Other Pharmaceutical (8)

6

T2ANIMAL HEALTH

8

5

Livestock

Companion Animal

2

2

2

Other Revenues (9)

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) Total Vaccines sales were $10,711 million and $13,448 million on a global basis for December YTD 2025 and 2024, respectively.

(5) 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.

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

(7) Total Diabetes sales were $2,862 million and $2,599 million on a global basis for December YTD 2025 and 2024, respectively.

(8) Includes Pharmaceutical products not individually shown above. Also reflects total alliance revenue for Koselugo of $436 million and $170 million on a global basis for December YTD 2025 and 2024, respectively.

(9) 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 upfront and milestone payments for out-licensed products were $138 million and $106 million on a global basis for December YTD 2025 and 2024, respectively.

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

PHARMACEUTICAL GEOGRAPHIC SALES

(AMOUNTS IN MILLIONS)

(UNAUDITED)

Table 3c

% Change

1Q

2Q

3Q

4Q

Full Year

1Q

2Q

3Q

4Q

Full Year

4Q

Full Year

TOTAL PHARMACEUTICAL

$

$

$

$

$

$

$

$

$

$

6

1

United States

% Pharmaceutical Sales

%

%

%

%

%

%

%

%

%

%

Europe(1)

2

% Pharmaceutical Sales

%

%

%

%

%

%

%

%

%

%

Japan

% Pharmaceutical Sales

%

%

%

%

%

%

%

%

%

%

Latin America

-5

-4

% Pharmaceutical Sales

%

%

%

%

%

%

%

%

%

%

Asia Pacific (other than China and Japan)

-4

-5

% Pharmaceutical Sales

%

%

%

%

%

%

%

%

%

%

China(2)

% Pharmaceutical Sales

%

%

%

%

%

%

%

%

%

%

Eastern Europe/Middle East/Africa

0

7

% Pharmaceutical Sales

%

%

%

%

%

%

%

%

%

%

Canada

6

-2

% Pharmaceutical Sales

%

%

%

%

%

%

%

%

%

%

Other

% Pharmaceutical Sales

%

%

%

%

%

%

%

%

%

%

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.

(2)Gardasil/Gardasil 9 sales in China were $193 million, $0, $0 and $0 in the first, second, third and fourth quarter of 2025, respectively,

and $1,253 million, $1,312 million, $517 million and $446 million in the first, second, third, and fourth quarter of 2024, respectively.

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

OTHER (INCOME) EXPENSE, NET - GAAP

(AMOUNTS IN MILLIONS)

(UNAUDITED)

Table 4

OTHER (INCOME) EXPENSE, NET

Full Year

Full Year

Interest income

$

)

$

)

$

)

$

)

Interest expense

Exchange losses

Loss (income) from investments in equity securities, net (1)

)

)

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

)

)

)

)

Other, net

)

)

)

)

Total

$

$

$

$

)

(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.