Annual Shareholders Meeting | 2019May 28, 2019

Annual Shareholders Meeting | 2019Ken FrazierChairman and CEO

Forward-looking StatementThis presentation 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 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 2018 Annual Report on Form 10-K and the company’s other filings with the Securities andExchange Commission (SEC) available at the SEC’s Internet site (www.sec.gov).

Our Strategy in Action

REINVENT DISCOVERY RESEARCH AND ADVANCE

THE PIPELINE

CREATE VALUE FOR SHAREHOLDERS AND

PATIENTS

DELIVER TOP AND BOTTOM LINE

GROWTH

MissionTo discover, develop and

provide innovative products and services that save and improve lives around the

world

VisionTo be the premier, research-intensive biopharmaceutical

company

ExecutionTo deliver growth and create

long-term sustainable shareholder value

Merck is well-positioned for growth and value creation by addressing unmet medical needs, delivering innovations for patients and returning capital to shareholders

HEADQUARTERSKenilworth, NJ, U.S. distributing to more than 140

countries

EMPLOYEESworldwide

(as of 12/31/18)

Merck & Co., Inc.is listed on the New York Stock Exchange and has a

market cap of ~ $200B

2018 REVENUES$42.3B, nearly 60% of sales from outside the U.S.

2018 R&D EXPENSE$9.8B (GAAP); Broad and diverse pipeline

BUSINESSESInnovative medicines and vaccines for human and animal health

$

About Merck

CAPITAL INVESTMENT$16B capital investment over 5 years, focused on expanding capabilities and capacity

Developed streptomycin, made

rights public

First synthesis

of cortisone

First long-term measles vaccine & first mumps

and rubella vaccines

Introduction ofpneumonia

vaccine

Developed MECTIZAN and

began donating it to eliminate river

blindness

Merck for Mothers established to

reduce maternal deaths worldwide

First to isolate broad-spectrum

antibiotics

Introduced thiabendazole,

first drug known to kill trichinella

in animals First anti-PD-1 therapy

approvedin the US

CRIXIVAN developed

for HIV FDA approves Merck

vaccines for HPV

Launch of investigational Ebola vaccine

2019>FOR MORE THAN A CENTURY, MERCK HAS BEEN INVENTINGTO SOLVE SOME OF THE GREATEST HEALTH CHALLENGES AROUND THE WORLD

<1890

First statin brought to

market

FY 2018 GAAP EPS

$2.32

FY 2018 NON-GAAP EPS

$4.34

FY2018 Highlights: Sales & EarningsP&L (Non-GAAP)

FY 2018 Ex-Exchange% vs. Prior

Sales $42.3B 5%

PGMPGM%

$31.9B75.4%

4%

Operating ExpenseSG&A ExpenseR&D Expense

$18.0B$10.1B$ 7.9B

2%0%6%

Net Income $11.6B 8%

EPS $4.34 11%

Q1 2019 Key Highlights

$1.0B-4% GROWTH

3% EX-EXCHANGE

$9.7B8% GROWTH

12% EX-EXCHANGE

STRONG GROWTH FROM KEYTRUDA, GARDASIL/GARDASIL 9,

PROQUAD/MMR /VARIVAX, LENVIMA, LYNPARZA AND BRIDION

CONTINUED STRENGTH IN COMPANION ANIMALS,POULTRY, AND SWINE

MERCK PHARMACEUTICAL SALES

KEY DRIVERS

ANIMAL HEALTH SALES

KEY DRIVERS

Q1 2019WORLDWIDE SALES

$10.8B8% GROWTH

11% EX-EXCHANGE

Q1 2019 Highlights: Sales & Earnings

GAAP EPS$1.12

NON-GAAP EPS$1.22 Q1 2019 Ex-Exchange

% vs. PriorSales $10.8B 11%PGM

PGM%$8.2B75.9%

9%

Operating ExpenseSG&A ExpenseR&D Expense

$4.4B$2.4B$2.0B

4%-1%11%

Net Income $3.2B 13%EPS $1.22 18%

P&L (Non-GAAP)

Oncology: Strong Keytruda And Lynparza Growth

1. All growth rates exclude the impact of foreign exchange.

• KEYTRUDA growth of +60%1 year-over-year including +69%1 in international markets• LYNPARZA sales doubled in the quarter driven by 1L ovarian maintenance launch (SOLO-1)

in the U.S. and expanded ovarian indication in Europe• Encouraging early customer feedback in adjuvant melanoma• Ex-U.S. approvals and reimbursement of KEYTRUDA 1L NSCLC (KEYNOTE-189 and

KEYNOTE-407)

Vaccines: Gardasil Global Uptake Remains Robust

• Vaccine sales growth of +24% driven by GARDASIL and GARDASIL 9, fueled by ongoing commercial launch in China and demand in Europe

• Pediatric vaccines, including PROQUAD / MMR-II / VARIVAX and ROTATEQ also contributed to vaccines growth

1. All growth rates exclude the impact of foreign exchange.

Hospital/Specialty: Bridion Demand Remains Strong

• BRIDION annualizing at over $1 billion. Growth in the U.S. reflects increased utilization of BRIDION in procedures where neuromuscular blockade reversal agents are used

• Ongoing PREVYMIS launch contributing to performance• Successful ZERBAXA trial in pneumonia with June 3 FDA PDUFA date

1. All growth rates exclude the impact of foreign exchange.

Animal Health: Sustained Performance

1. All growth rates exclude the impact of foreign exchange.

International growth offsets U.S. decline highlighting benefits of global scale• Growth in companion animals, led by BRAVECTO, drove sales in the quarter. Growth also

supported by new poultry and swine product sales• Customer buying patterns within the U.S. business for livestock as well as a 7% negative

impact from FX, offset demand growth• Closed acquisition of Antelliq group, which establishes Merck as a leader in digital animal

identification, traceability and monitoring solutions

s\

Robust International Pharmaceutical Growth Led By China

UnitedStates

CanadaEurope2

LatinAmerica

Eastern Europe / Middle East

AfricaAsia

PacificEx-China

Japan

+14%

1 All growth rates exclude the impact of exchange.2 Europe primarily represents all European Union countries and the European Union accession markets.Based on Q1 2019

China

EX-U.S. GLOBAL PHARMACEUTICAL SALES +12%

$343M

+4%

+3%

+67% +9%

+25%

+12%

-4%

“We try never to forget that medicine is for the people. It is not for the profits. The profits follow, and if we have remembered that, they have never failed to appear.”— George W. Merck

Annual Shareholders Meeting | 2019Roger Perlmutter

WHERE WE BEGAN: DRAMATIC RESPONSES OBSERVED FOLLOWING TREATMENT OF MELANOMA WITH KEYTRUDA

Baseline: 13 April 2012 27 July 2012

Courtesy of A. Ribas M.D.

-100

0

100

WHERE WE ARE TODAY: KEYTRUDA MONOTHERAPY SHOWS ACTIVITY AGAINST A BROAD RANGE OF TUMORS

-100

0

100

-100

0

100Melanoma1

-100

0

100 NSCLC2

-100

0

100Gastric6

-100

0

100

-100

0

100H&N3 TNBC5

-100

0

100cHL7

-100

0

100NHL PMBCL8Urothelial4

Chan

ge F

rom

Bas

elin

e in

Tum

or S

ize,

%

-100

0

100Mesothelioma9

-100

0

100Anal14

-100

0

100

-100

0

100SCLC11

-100

0

100NPC13

-100

0

100Biliary Tract15

-100

0

100Colorectal16Esophageal12

-100

0

100Ovarian10

-100

0

100ER+/HER2– BC17 Cervical18 Thyroid19 Salivary20 Endometrial21 Prostate22 GBM23

-100

0

100

-100

0

100

-100

0

100

-100

0

100

-100

0

100

-100

0

100MSI-H24

1. Daud A et al. ASCO 2015; 2. Garon EB et al. ESMO 2014; 3. Seiwert T et al. ASCO 2015; 4. Plimack E et al. ASCO 2015; 5. Nanda R et al. SABCS 2014; 6. Bang YJ et al. ASCO 2015 ; 7. Moskowitz C et al. ASH 2014; 8. Zinzani PL et al. ASH 2015; 9. Alley EA et al. AACR 2015; 10. Varga A et al. ASCO 2015; 11. Ott PA et al. 2015 ASCO; 12. Doi T et al. ASCO 2015; 13. Hsu C et al. ECC 2015; 14. Ott PA et al. ECC 2015; 15. Bang Y-J et al. ECC 2015; 16. O’Neil B et al. ECC 2015; 17. Rugo HS et al. SABCS 2015; 18. Frenel JS et al. ASCO 2016; 19. Mehnert JM et al. ASCO 2016; 20. Cohen R et al. ASCO 2016; 21. Ott PA et al. ASCO 2016; 22. Hansen AR et al. ESMO 2016; 23. Reardeon D et al. SNO 2016; 24. Diaz L et al. ASCO 2017.

IMMUNOTHERAPY IN ONCOLOGY:BENDING THE SURVIVAL CURVE?

ControlStandard or other therapy

Immune manipulationCombination

0 4 8 1 2 1 6 2 0 2 40

1 0

2 0

3 0

4 0

5 0

6 0

7 0

8 0

9 0

1 0 0

M o n th s

OS

, %

N o . a t R is k432 417 378 256 18429 401 341 211 20

136110

00

COMBINED TREATMENT IMPROVES OVERALL SURVIVAL AS COMPARED WITH STANDARD THERAPY IN KIDNEY CANCER

Pts w/ Event Median

Pembro + Axi 13.7% NRSunitinib 22.6% NR

12-mo rate89.9%78.3%

18-mo rate82.3%72.1%

HR 0.53 (95% CI 0.38-0.74)P < 0.0001

Presented at ASCO GU Conference, February 2019

PROGRESS CONTINUES IN DEVELOPING A BROAD RANGE OF NEW MEDICINES AND VACCINES

CANCER

- KEYTRUDA- LENVIMA- LYNPARZA- More than 20

novel anti-cancer agents

INFECTIONS

- ZERBAXA- RELEBACTAM- PREVYMIS- MK-8591- Novel anti-

bacterial and anti-viral agents

VACCINES

- V114 (PCD)- V160 (CMV)- V181 (Dengue)- V920 (Ebola)

MERCK EXCELS AT GENERATING NOVEL CHEMICAL STRUCTURES THAT ADDRESS GRIEVOUS ILLNESS

N

NN

N

NH2

O

OH

OPO

HS

OO P

OSH

O F

HN

N

NO

H2N N

HF

O

HO

HON

N

NH2

N

N FMK-8591HIV Inhibitor

MK-1454STING Agonist

Keytruda

“We must look at Nature with the eyes of a chemist, not just for what she’s done, but for what she could do”

—Frances H. Arnold

RIVALING NATURE: BIOCATALYTIC MANUFACTURING ROUTES

MK-1454

O

O

N

N N

N

NH2

O

F

PO

O

ON

N

NHN

O

NH2

F

PO

SO

SNa

Na

O

HO

HO N

N

NH2

N

N F

MK-8591

N

ONH2

FF

F N NN

CF3

• H3PO4

Sitagliptin

Innovation at the interface of biology and chemistry

• Molecular evolution generates novel synthetic approaches

• Rapid discovery of new compounds

• Efficient approaches to continuous manufacturing

Annual Shareholders Meeting | 2019Ken Frazier

1-800-CALLMRK(1-800-225-5675)or visit www.merck.com

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