Merck Oncology Overview ASCO 2020

Forward-looking statement

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This 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 the recent 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).

We are executing on a broad oncology strategy to improve outcomes for cancer patients globally

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Further establishKEYTRUDA as foundational treatment and advance into earlier stages of disease

Broadly explorecombinations to reach more patients

Advance pipeline and pursue strategic collaborations and acquisitions to expand portfolio

Identify patients most likely to benefit using biomarkers

KEYTRUDA has now demonstrated activity in more than 30 different types of cancer defined by site of origin, histology, or genetic markers

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-100

0

100

-100

0

100

-100

0

100

-100

0

100

-100

0

100

-100

0

100

-100

0

100NSCLC2

-100

0

100Gastric6

-100

0

100

-100

0

100H&N3 TNBC5

-100

0

100cHL7Urothelial4

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 HCC16Esophageal12

-100

0

100Ovarian10

-100

0

100ER+/HER2– BC17 Cervical18

Thyroid19 Salivary20 Endometrial21

-100

0

100Melanoma1

-100

0

100Biliary Tract15

-100

0

100Prostate22 GBM23

-100

0

100

-100

0

100MSI-H CRC24

-100

0

100

-100

0

100Carcinoid25

-100

0

100pNET25

ccRCC27 nccRCC28

-100

0

100MSI-H non-CRC24

-100

0

100Merkel Cell26

-100

0

100

tTMB-H29

-100

0

100

cSCC30

-100

0

100

-100

0

100NHL PMBCL8

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. Marabelle A et al. ASCO 2020; 15. Bang Y-J et al. ECC 2015; 16. Zhu A et al. ASCO 2018; 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. Reardon D et al. SNO 2016; 24. Diaz L et al. ESMO 2017; 25. Mehnert J et al. ESMO 2017; 26. Nghiem P et al. ASCO 2018; 27. McDermott DF et al. ASCO 2018; 28. McDermott DF et al. ASCO-GU 2019; 29. Marabelle A et al. ESMO 2019; 30. Grob JJ et al. ESMO 2019.

= cancer types with approved indications

KEYTRUDA monotherapy and in combination improves overall survival in Phase 3 studies across a broad range of malignancies

N o . a t R is k

0 5 1 0 1 5 2 0 2 5 3 0 3 5 4 0 4 5 5 00

1 0

2 0

3 0

4 0

5 0

6 0

7 0

8 0

9 0

1 0 0

M o n t h sO

S, %

2 5 7 1 9 7 1 5 2 1 1 0 7 02 5 5 2 0 7 1 3 1 8 9 4 0

9 15 9

00

4 32 1

2 19

1 35

10

2L+ NSCLC, TPS ≥50%

KEYNOTE-045Pembro vs Chemo

2L Bladder, Any PD-L1

KEYNOTE-024Pembro vs Chemo

1L NSCLC, TPS ≥50%

KEYNOTE-181Pembro vs Chemo

1L Esophageal, CPS ≥10

KEYNOTE-048Pembro vs EXTREME

1L HNSCC, CPS ≥1

0 1 0 2 0 3 0 4 0 5 0 6 0

0

1 0

2 0

3 0

4 0

5 0

6 0

7 0

8 0

9 0

1 0 0

M o n t h s

OS

, %

N o . a t R is k2 9 0 1 7 8 1 3 1 1 0 1 11 5 2 5 8 2 9 2 1 1

5 01 0

00

0 6 12 18 24 30 36 42 480

10

20

30

40

50

60

70

80

90

100

Months

OS,

%

No. at Risk270 170 116 86272 140 73 47

6935

00

6028

5226

1712

0 6 12 18 24 30 36 42 480

10

20

30

40

50

60

70

80

90

100

Months

OS,

%

No. at Risk154 121 89 78 50151 108 61 48 24

7344

56

10680

6635

0 6 12 18 24 30 36 42 480

10

20

30

40

50

60

70

80

90

100

Months

OS,

%

No. at Risk637 463 368 304 91367 485 319 236 65

178126

00

12

3020

0 4 8 12 16 20 24 28 32 360

10

20

30

40

50

60

70

80

90

100

Months

OS,

%

No. at Risk107 86 59 45 10115 76 48 23 9

2914

00

54

01

2114

0 4 8 1 2 1 6 2 0 2 4 2 8 3 20

1 0

2 0

3 0

4 0

5 0

6 0

7 0

8 0

9 0

1 0 0

M o n t h s

OS

, %

N o . a t R is k2 7 8 2 3 7 1 9 0 1 1 01 3 5 1 1 3 8 4 4 2

1 5 26 5

00

5 72 3

1 68

11

KEYNOTE-240Pembro vs Placebo2L HCC, Any PD-L1

0 5 1 0 1 5 2 0 2 5 3 0

0

1 0

2 0

3 0

4 0

5 0

6 0

7 0

8 0

9 0

1 0 0

M o n t h sO

S, %

N o . a t R is k2 4 7 1 6 0 1 0 32 4 8 1 5 1 8 2

4 83 4

00

1 41 0

21

KEYNOTE-040Pembro vs SOC

2L+ HNSCC, Any PD-L1

1L Gastric, CPS ≥10

KEYNOTE-006Pembro vs Ipi

Ipi-Naive Melanoma, Any PD-L1

0 10 20 30 40 50 600

10

20

30

40

50

60

70

80

90

100

Months

OS,

%

No. at Risk556 416 317 264278 158 111 94

4719

23385

20875

OS

OS

OS

OS

OS

OS

OS

0 5 10 15 20 25 30 35 400

10

20

30

40

50

60

70

80

90

100

Months

OS,

%

No. at Risk96 79 57 41 2398 80 54 36 12

00

114

11

2623

KEYNOTE-119Pembro vs Chemo

2/3L TNBC, CPS ≥10

OS

OS

OS

KEYNOTE-042Pembro vs Chemo

1L NSCLC, TPS ≥1%

KEYNOTE-010Pembro vs Docetaxel

0 6 1 2 1 8 2 4 3 0 3 6 4 20

1 0

2 0

3 0

4 0

5 0

6 0

7 0

8 0

9 0

1 0 0

M o n t h s

OS

, %

N o . a t R is k9 2 6 2 5 29 0 7 0 4 2

4 52 8

00

3 21 6

1 37

40

OS

KEYNOTE-062Pembro vs Chemo

KEYNOTE-189Pembro + Pemetrexed/Platinum vs

Placebo + Pemetrexed/Platinum1L Nonsquamous NSCLC, Any PD-L1

0 3 6 9 1 2 1 5 1 8 2 1 2 4 2 7 3 0 3 3

0

1 0

2 0

3 0

4 0

5 0

6 0

7 0

8 0

9 0

1 0 0

M o n t h s

OS

, %

N o . a t R is k4 1 0 3 7 7 3 4 6 2 5 6 7 92 0 6 1 8 3 1 4 9 8 2 2 6

2 3 47 2

00

2 81 0

3 1 61 1 5

2 8 39 9

1 4 44 5

20

OS

0 6 12 18 24 300

10

20

30

40

50

60

70

80

90

100

Months

OS,

%

No. at Risk228 175 60225 170 44

10289

158

10

KEYNOTE-604Pembro + EP vs

Placebo + EP 1L SCLC, Any PD-L1

OS

KEYNOTE-407Pembro + Carboplatin/Taxane vs

Placebo + Carboplatin/Taxane1L Squamous NSCLC, Any PD-L1

0 3 6 9 1 2 1 5 1 8 2 1

0

1 0

2 0

3 0

4 0

5 0

6 0

7 0

8 0

9 0

1 0 0

M o n t h s

OS

, %

N o . a t R is k2 7 8 2 5 6 1 8 8 1 2 4 1 72 8 1 2 4 6 1 7 5 9 3 1 6

6 24 5

00

24

OS

KEYNOTE-426Pembro + Axitinib vs

Sunitinib1L RCC, Any PD-L1

0 4 8 1 2 1 6 2 0 2 4

0

1 0

2 0

3 0

4 0

5 0

6 0

7 0

8 0

9 0

1 0 0

M o n t h s

OS

, %

N o . a t R is k4 3 2 4 1 7 3 7 8 2 5 6 1 84 2 9 4 0 1 3 4 1 2 1 1 2 0

1 3 61 1 0

00

OS

KEYNOTE-048Pembro + Platinum

vs EXTREME1L HNSCC, Any PD-L1

0 5 1 0 1 5 2 0 2 5 3 0 3 5 4 0

0

1 0

2 0

3 0

4 0

5 0

6 0

7 0

8 0

9 0

1 0 0

M o n t h s

OS

, %

N o . a t R is k2 8 1 2 2 7 1 6 9 1 2 2 4 02 7 8 2 2 7 1 4 7 1 0 0 2 0

7 55 1

00

1 05

11

OS

Monotherapy

Combinations

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6

Comprehensive KEYTRUDA development program

>1,200Ongoing

clinical trials

Registrational trials under way

>90

Combination trials>800

Trials in adjuvant / neoadjuvant

and earlier lines

>110

ASCO 2020: Continued flow of data from deep & diverse oncology portfolio

New Phase 3 data for KEYTRUDA in TNBC, MSI-H CRC and cHL

New Phase 2 data for KEYTRUDA in Stage III NSCLC

Demonstrating KEYTRUDA’s long-term survival benefits

Long-term survival data for KEYTRUDA in NSCLC, RCC and Melanoma

Progressing novel mechanisms

New Phase 2 data from our oral HIF-2α inhibitor in VHL RCC

MK-6482 now in Phase 3 in 2L RCC

Presenting new KEYTRUDA data

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KEYNOTE-355: Improved efficacy and supportive of overall TNBC development program

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KEYTRUDA plus chemo reduced the risk of disease progression or death by 35% vs. chemo for certain TNBC patients (HR = 0.65 [95% CI, 0.49-0.86], p=0.0012)

Trial continues for OS

Data cutoff: Dec. 11, 2019

Progression-Free Survival: PD-L1 CPS > 10

KEYNOTE-177: Single-agent KEYTRUDA may become new standard of care in 1L MSI-H mCRC patients

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Median (95% CI)16.5 mo (5.4-32.4)8.2 mo (6.1-10.2)

0 4 8 12 16 20 24 28 32 36 40 44 480

102030405060708090

100

Time, months

PFS,

%

No. at Risk153 96 77 72 64 60 55 37 20 7 5 0 0154 100 68 43 33 22 18 11 4 3 0 0 0

12-mo rate55%37%

24-mo rate48%19%

KEYTRUDA monotherapy significantly reduced risk of disease progression or death by 40% and more than doubled median PFS versus chemo (HR = 0.60 [95% CI, 0.45-0.80], p=0.0002)

Trial continues for OS

Data cutoff: Feb. 19, 2020

KEYNOTE-204: Displacing standard of care in2L+ relapsed refractory classic Hodgkin’s lymphoma

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KEYTRUDA monotherapy showed statistically significant and clinically meaningful improvement in PFS versus BV in R/R cHL (HR = 0.65 [95% CI, 0.48-0.88], p=0.00271)

Trial continues for OS

Data cutoff: Jan. 16, 2020

Long-term follow-up data confirm durable overall survival benefits with KEYTRUDA used in combination or as an adjuvant following surgery

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+XX% YOY

NSCLC RCC Melanoma

In the final analysis of KEYNOTE-189, KEYTRUDA in combination with chemotherapy reduced the risk of death by 44% versus chemotherapy and at two years, demonstrated a sustained, long-term survival benefit in metastatic NSCLC.

An updated analysis from KEYNOTE-426 showed the combination of KEYTRUDA plus axitinib continued to demonstrate durable anti-tumor activity vs. sunitinib.

In a 3-yr follow-up on KEYNOTE-054, KEYTRUDA as adjuvant therapy, provided, a sustained improvement in RFS, which was clinically meaningful, in resected high-risk stage III melanoma.

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VHL disease is a multi-system disease with most patients having several different tumors

Data demonstrates the therapeutic potential for MK-6482 (HIF-2α) in VHL-associated ccRCC patients, where there is a high unmet need

• 27.9% ORR and 86.9% of patients saw a decrease in target lesion size

Beyond patients with VHL disease, Phase 2 data presented in 2019 demonstrated the potential as monotherapy for treatment of advanced or metastatic RCC, particularly in PD-1/PD-L1 refractory patients with 24% partial responses (PR) and 54% stable disease (SD)

Phase 3 trial under way studying MK-6482 vs. everolimus in patients with advanced 2L RCC who have progressed following treatment with PD-1/PD-L1 combined with VEGF targeted therapy

MK-6482: First-time data shows promising overall response ratein Von-Hippel Lindau (VHL)-associated kidney cancer patients

Benign Tumors

• CNS Hemangioblastoma (70-80%)• Retinal Hemangioblastoma (50-60%)• Pancreatic Cyst and Cystadenoma (50%)• Endolymphatic Sac Tumor

of the middle ear (10-25%)• Tumor of the Epididymis or Broad

Ligament (10-60%)

Areas of the Body Affected by von Hippel-Lindau Disease

Advanced/Malignant Tumors

• RCC (25-60%)• Pheochromocytoma (10-20%)• Pancreatic NET (10-20%)

KEYTRUDA is being explored in a broad adjuvant program with 20 registrational studies ongoing

2018 2019 2020 2021 2022 2023 2024 2025 2026+

Adjuvant Melanoma (KEYNOTE-054) APPROVED

TNBC Neoadjuvant / Adjuvant(KEYNOTE-522)

pCR presented

cSCC Locally Advanced (KEYNOTE-629) PDUFA: JUNE 29

HNSCC Adjuvant (KEYNOTE-412)

NSCLC Adjuvant (KEYNOTE-091)

Adjuvant Melanoma (KEYNOTE-716)

RCC Adjuvant (KEYNOTE-564)

Gastric & Esophageal Adjuvant / Neoadjuvant (KEYNOTE-585)

HNSCC Adjuvant / Neoadjuvant (KEYNOTE-689)

NSCLC Neoadjuvant (KEYNOTE-671)

Neo/adjuvant MIBC (KEYNOTE-866)

Neo/adjuvant MIBC (KEYNOTE-905)

NSCLC Stage I/IIa (KEYNOTE-867)

HCC Adjuvant (KEYNOTE-937)

Ovarian BRCAwt + chemo (KEYLYNK-001)

TNBC Adjuvant (KEYNOTE-242)

cSCC Locally Advanced (KEYNOTE-630)

ER+ / HER2-Breast Cancer Adjuvant / Neoadjuvant (KEYNOTE-756)

Timeline based on clinicaltrial.gov primary completion dates. Actual timing may vary.13

Extensive KEYTRUDA+LYNPARZA combination (KEYLYNK) and LYNPARZA monotherapy programs

• 1L, nonBRCA, KEYTRUDA combo (KEYLYNK-001)• 1L Maintenance BRCA+ (SOLO-1) - Approved

• 1L Maintenance, All Comers Combo + Bev (PAOLA-1) - Approved

• PSR, All Comers Combo + Cediranib (GY004)

• PRR, All Comers Combo + Cediranib (GY005)

• 2L+ PSR (SOLO2/Study19 ) - Approved

• 3L+ PSR, gBRCA Treatment (SOLO3)

• TNBC (KEYLYNK-009)• mBC, gBRCA (OlympiAD) - Approved

• HER2- Adjuvant, gBRCAm (OlympiA)

• 1L Maintenance gBRCA (POLO) - Approved

• mCRPC, All Comers (KEYLYNK-010)• mCRPC, HRRm (PROfound) - Approved

• mCRPC, All Comers Combo + Abiraterone (PROpel)

• 1L NSQ NSCLC (KEYLYNK-006)• 1L SQ NSCLC (KEYLYNK-008)• Stage III NSCLC (KEYLYNK-012)

• HRRm/HRD Basket (KEYLYNK-007)• HRRm Basket (LYNK-002)

LungCancer

TumorAgnostic

Ovarian cancer

Breastcancer

Pancreaticcancer

Prostatecancer

Lung cancer

Tumoragnostic

PRR: Platinum Relapsed Recurrent; PSR: Platinum Sensitive RecurrentCollaboration with AstraZeneca

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Extensive KEYTRUDA+LENVIMA combination (LEAP) and LENVIMA monotherapy programs

• 1L RCC Combo with Evero or KEYTRUDA (KN-581 / Study 307)

• 2L RCC Combo with Evero (Study 205) - Approved

• 1L EC (LEAP-001)• 2L EC (Study 309 / KN-775)• 2L EC (KEYNOTE-146) -

Approved

• 1L HCC Combo (LEAP-002)

• 1L HCC Combo/TACE (LEAP-012)• 1L HCC Mono (Study 304) – Approved

• 1L Melanoma (LEAP-003)• 2L Melanoma (LEAP-004)

• 1L UC (LEAP-011)

• 1L PD-L1+ HNSCC (LEAP- 010)

• TNBC

• Gastric

• Ovarian

• Colorectal

• Glioblastoma

• Biliary

• 1L NSQ Combo with KEYTRUDA and Chemo (LEAP-006)

• 1L PD-L1+ NSCLC (LEAP-007)• 2L NSQ (LEAP-008)

• 1L Thyroid -Approved

Endometrialcarcinoma

Hepatocellular carcinoma

Melanoma

Renal cell carcinoma

Thyroidcancer

Lungcancer

Urothelialcancer

Head & neck cancer

Basket trial

Registrational studies onlyCollaboration with Eisai

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Early oncology pipeline* includes more than 20 investigational immuno-therapeutic candidates – including novel combinations with KEYTRUDA

Personalized Cancer Vaccines

Tumor Microenvironment Modulators

Therapeutic vaccines based on patients’ specific cancer could

potentially prime the immune system to recognize certain characteristics

and attack the cancer cells

Regulating the environment around tumors, including

through oncolytic viruses, may influence tumor growth and its

interaction with the immune system

Phase 1 Phase 2

ImmuneAgonists

Molecules designed to stimulate immune system

functions, such as enhancing the activity of anti-tumor

immune cells

RIG-I receptor(MK-4621)

CD-27 agonist (MK-5890)

STING agonist (MK-1454)

Phase 1/2

Inhibition of Negative Immune Regulators

Blocking the action of molecules that suppress the

immune system may trigger a more robust anti-tumor

response

ILT4 antagonist (MK-4830)

LAG3 (MK-4280)

CTLA4 (MK-1308)

TIGIT (MK-7684)

RNA-based vaccine (Moderna)

(V940 / mRNA-4157)

CDK 1, 2, 5, 9(MK-7965)

V937 oncolytic virus (formerly CAVATAK)

BTK Inhibitor(MK-1026)

AKT Inhibitors(MK-7075 & MK-4440)

Pre-Clinical

TGFβ(Tilos Therapeutics)

KRAS (Moderna)(V941 / mRNA-5671)

KRAS – Taiho/Astex

*Select compounds only

ERK Inhibitor(MK-8353)

HIF-2α Inhibitor(MK-6482)

We have pursued collaborations, licensing agreements, and acquisitions that will increase our ability to provide benefit to cancer patients

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Development StageDevelopment Program

Kinase inhibitory discovery and development for treatment of patients with cancer and other diseases

Portfolio of investigational antibodies modulating TGFβ complex for the treatment of cancer, fibrosis and autoimmune disease

Development of novel small molecule therapeutic candidates targeting HIF-2α for the treatment of patients with cancer and other diseases

Collaboration for the development of small molecule inhibitors against several drug targets, including the KRAS oncogene

Gain access to an investigational intratumoral and intravenous formulationof the Coxsackievirus Type A21, designed to infect and kill cancer cells

Phase 2 in CLL

Preclinical

Phase 3 in RCC

Preclinical

Phase 2 in melanoma

Acquisition

Creating long-term value for patients, employees and shareholders

Anchored by our deep bench of talent, commitment to our mission & focus on breakthrough science and innovation

Next 5 YearsStrong execution driving sustainable revenue growth, meaningful margin expansion and accelerated bottom-line growth

5-10 YearsRich pipeline addressing areas of high unmet need to drive performance over the next 5 to 10 years

10+ YearsRevitalized discovery efforts and increased expertise in biology to deliver ongoing scientific breakthroughs for decades to come

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