Leaders in Managing Lipids for

Improved Cardiovascular Health

INVESTOR PRESENTATION

June 2015

Nasdaq: AMRN

2

Forward-Looking Statement and Disclaimer

This presentation contains forward-looking statements, such as those relating to the

commercial potential of Vascepa®, Amarin’s product development, clinical and

regulatory efforts and timelines, potential FDA approvals, intellectual property, cash

flow, and other statements that are predictive in nature and that depend upon or refer

to future events or conditions. These statements involve known and unknown risks,

uncertainties and other factors that can cause actual results to differ materially.

Investors should not place undue reliance on forward-looking statements, which

speak only as of the presentation date of this presentation. Please refer to the “Risk

Factors” section in Amarin’s most recent Quarterly Report on Form 10-Q filed with the

SEC for a more complete description of risks of an investment in Amarin.

Vascepa® (icosapent ethyl) capsules are FDA approved for use as an adjunct to diet

to reduce triglyceride (TG) levels in adult patients with severe (TG >500 mg/dL)

hypertriglyceridemia (commonly known as very high TGs).

This presentation is intended for communication with investors only. Nothing in this

presentation should be construed as marketing the use of Amarin’s product or

product candidates.

3

Amarin: Blockbuster Opportunity and Growing Revenues

Upcoming: Cardiovascular outcomes data on

Vascepa® (>96% ethyl-EPA1) as add-on to statins

REDUCE-IT CV outcomes study >93% enrolled

Events driven study incorporates learnings from positive

JELIS (Japan CV outcomes study of EPA) and others

Leverages strong lipid efficacy & safety profile: two Phase 3s

Studying at-risk patients with persistent elevated triglycerides

CV outcomes results expected 2018, potentially 2016

Today: Marketing Vascepa for very high TGs

U.S. launch in 2013

$54M in revenues in 2014 and growing

Marketing concentrated on top physician targets

Co-promotion partner Kowa Pharmaceuticals America added

in mid-2014 adds to Amarin’s 130 sales reps

Addressing chronic patient condition

1EPA: eicosapentaenoic acid, a unique polyunsaturated omega-3 fatty acid

4

Cardiovascular Risk: Significant Unmet Need

Cardiovascular Disease: #1 cause of death in the United States

>700,000 people die of heart disease in the United States every year

‒ Represents ~1 in every 3 deaths (AHA Heart and Stroke Statistics)

Heart attacks, stroke and other CV disease are expensive to treat

‒ Estimated annual total cost of >$300 billion

Standard of care first therapy beyond diet and exercise: Statins

$40.2 billion annual market at its height

Statins target LDL-C and are reported to have other “pleiotropic” effects such as:

‒ Improving endothelial function

‒ Enhancing the stability of atherosclerotic plaques

‒ Decreasing oxidative stress and inflammation

Statins lower coronary heart disease risk by up to 25 to 40%

5

Seeking Solution to Address Residual Cardiovascular Risk

Limited success in prior CV outcomes studies with statin add-on therapies Ezetimibe (IMPROVE-IT):

‒ ~6% additional risk decline

‒ Focus on additional LDL-C lowering, other lipid reductions

Fenofibrate (ACCORD-Lipid)

‒ No benefit in general population of low HDL-C patients

‒ Benefit trend seen in high TG, low HDL-C subset population

Niacin: HDL-C increase focus (AIM-HIGH and HPS2-THRIVE)

‒ No benefit in the AIM-HIGH general population of low HDL-C patients

‒ In AIM-HIGH, benefit seen in high TG, low HDL-C subset population

‒ No benefit in the HPS2-THRIVE population with half of the patients having low

HDL-C

Exception: 19% to 53% risk reduction in Japan-based study Ethyl-EPA (JELIS):

‒ Benefit shown in general population of statin treated patients

‒ Greater benefit in patient subpopulation with high TG and low HDL-C

6

Ethyl-EPA Reduced Coronary Events 19% to 53% on

Top of Statin Therapy in Japan Outcomes Study (JELIS)

Patients Randomized to Statin Alone or Statin + Ethyl-EPA (Epadel) and Followed

for 5 Years with Comparison of Cumulative Incidence of Major Coronary Events

–53%

HR: 0.4795%CI: 0.23-0.98(p=0.043)

0 1 2 3 4 50

1

2

3

4

5

Years5210 3 4

3

0

1

2

4 Control (statin)

EPA (statin+Epadel)

Years

TOTAL COHORTNo pre-specified minimum TG level TG>150 mg/dL and HDL<40 mg/dL

SUB GROUP

N=957

Control (statin)

EPA (statin+Epadel)

Control (statin)

EPA (statin+Epadel)

Source: Yokoyama M. et al, Lancet 2007; 369:1090-1098

P value adjusted for age, gender, smoking, diabetes, and hypertension.

CI=confidence interval.

Source: Saito et al, Atherosclerosis 2008; 200: 135-140

N=18,645(p=0.011)

-–19%

Cum

ula

tive I

ncid

ence o

f M

ajo

r C

oro

nary

Events

(%

)

Cum

ula

tive I

ncid

ence o

f M

ajo

r C

oro

nary

Events

(%

)

7

Ethyl-EPA: Lowers Triglycerides (TGs)

Plus Spectrum of Other Lipid and Pleiotropic Effects

Triglycerides (fat in blood) lowered Studied by Amarin in two Phase 3 studies

‒ MARINE trial: TGs >500mg/dL and ANCHOR trial: TGs 200-499mg/dL on statins

Also significantly lowered other key lipid parameters including total cholesterol,

Non-HDL-C, Apo-B, Apo-CIII, VLDL-C and remnant-like particle cholesterol

Did not increase LDL-C (bad cholesterol)

Pleiotropic effects of EPA beyond lipid improvements1

Improves endothelial function ‒ Alone and in combination with statin therapy

Anti-inflammatory effects ‒ Lowers Lp-PLA2 and hsCRP (>14% and >22% declines, respectively, vs. placebo in

Phase 3 Vascepa studies)

Anti-oxidant effects ‒ More potent antioxidant than historically used TG-lowering therapies and vitamin E

Inhibits formation of cholesterol crystalline domains; disrupts existing domains

‒ No other TG-lowering therapy has been shown to share all these effects

1Pleiotropic effects based on clinical and non-clinical scientific literature

8

Lowering TGs in Patients with Baseline TG>150 mg/dL and low HDL-C in Outcomes Studies Suggests Double Digit Relative Risk Reduction (RRR) on Top of Statin Therapy

Trial

Publication

Year

Therapy

Subgroup

Size

(N)

Statin

Use

Through-

out

Subgroup

PublishedEndpoint

Subgroup

RRR

(p-value)

JELIS

2007EPA 957 Yes

TG ≥150 mg/dL

HDL-C ≤40 mg/dL

Expanded

MACE

-53%(0.043)

ACCORD-

Lipid

2010

Fenofibrate 941

Delayed

start (inflates starting

baselines)

TG ≥204 mg/dL

HDL-C ≤34 mg/dLMACE

-31%(0.0567)

AIM-HIGH

2011Niacin ER 523 Yes

TG ≥ 200 mg/dL

HDL-C <32 mg/dL

Expanded

MACE

-36%(0.032)

HPS2-

THRIVE

2013

Niacin +

Laropiprant4,362 Yes

TG ≥151 mg/dL

HDL-C <35 mg/dL

Major

vascular

events

No

significant

difference

CONFIDENTIAL

9

Genetic Studies: TG Levels Predict Heart Disease (CHD)

Predictor

CHD Risk

Effect Size Perspective P-value

TG 0.40 TGs and LDL-C

levels are

comparably strong

predictors of CHD

<<<0.0001

LDL-C 0.39 <<<0.0001

HDL-C 0.04HDL-C is weak

predictor0.32

Modified from:

Do R et al. Nat Genet. 2013;45(11):1345-1352 (N=86,995);

10

Broad Data Supports Link Between TGs and CV Risk

• Epidemiological, genetic, and clinical data suggest that TGs and the lipoproteins that carry them are within the

causal pathway of CV disease, and that treating elevated TGs may result in reduced CV risk.

11

Amarin: Positioned with First Outcomes Study of Ethyl-

EPA as Add-on to Statin Outside of Japan

Purpose of REDUCE-IT cardiovascular outcomes study: Evaluate effectiveness of Ethyl-EPA (Vascepa) in reducing cardiovascular events

in at risk patients

FDA has strongly urged Amarin to complete REDUCE-IT outcomes study

Addresses unanswered medical questions; 1st outcomes study designed to

prospectively evaluate each of: TG-lowering in patients with elevated TGs despite statin therapy

Ethyl-EPA on top of statins in a broad-based patient population

CV outcomes benefit in REDUCE-IT to be measured by: Randomizing statin treated patients to placebo and to Ethyl-EPA (Vascepa)

Measuring cumulative incidence of major CV events (death, myocardial infarction,

stroke, coronary revascularization and hospitalization for unstable angina)

Comparing cumulative first CV events in active vs. placebo trial arms

12

REDUCE-IT Approaching Key Milestones

DESIGN

SPA Agreement reached with FDA in 2011

– ~8,000 Patients on optimized statin therapy

– Population with CVD or “at Risk,” incl. TGs

>150 mg/dL

– 90% power to detect 15% relative risk

reduction (>95% power to detect >20% relative

risk reduction)

– Amarin blind to ongoing trial results

STATUS

>7,400 patients enrolled (>93% of target)

Enrollment completion anticipated in 2015

– Enrolling in 11 countries at >450 clinical sites

– Safety data reviewed throughout study by DMC

– Mean and median baseline TG of >200 mg/dL

(higher than levels enrolled for recent outcome

studies of other lipid modifying therapies)

TIMING

Complete at 1,612 composite MACE events

– First patient randomized November 2011

– Interim efficacy look ~2016

By independent data monitoring committee, DMC,

pre-specified at 967 events (60% of target events)

– Completion of 100% of target events ~2017

– Publication ~2018

OPPORTUNITY

Incremental risk reduction beyond statin

therapy

Positioned to address patient populations of

>70 million in U.S. alone; billions of dollars

Unique product profile

13

REDUCE-IT and JELIS Study Design Differences

“Enriched” Patient Population in REDUCE-IT

REDUCE-IT: all patients have elevated TG’s and other CV risk factors despite statin therapy

– Mean and median baseline TG’s >200 mg/dL and ~1/2 of patients expected to also have low HDL

JELIS: many patients had normal TG levels and a 19% risk reduction was achieved

– Published subgroup with 53% risk reduction population had TG >150 mg/dL and low HDL

Higher Treatment Dose in REDUCE-IT

REDUCE-IT 4 grams/day of ethyl-EPA (Vascepa); JELIS 1.8 grams/day of ethyl-EPA

In 12-week Phase 3 ANCHOR study, 4 grams/day of Vascepa increased EPA at the plasma

level to the same level as achieved with 1.8 grams/days of ethyl-EPA in JELIS

– Difference likely due to high fish diet in Japan

– EPA levels in REDUCE-IT control likely lower than JELIS due to dietary differences outside Japan

Statin therapy targeted to goal in REDUCE-IT and JELIS

– REDUCE-IT LDL-C target <100 mg/dL; JELIS LDL-C target <130 mg/dL; studies of statin therapy

demonstrated similar outcome results in Japan at <130 mg/dL to Western populations at 100 mg/dL

REDUCE-IT is a Global Study

REDUCE-IT: enrollment in 11 countries including strong participation in the United States;

randomized double blinded study

JELIS: Japan only, mostly women; open label, randomized with blinded endpoint analysis

14

Elevated TGs More Prevalent than Elevated LDL-C

Tens of millions of people have lipid disorders 13.1% of U.S. adults have elevated LDL-C

25.1% of U.S. adults have above normal TGs

Lipid disorders contribute to atherosclerosis,

heart disease, pancreatitis and other health

issues

REDUCE-IT: Focused on statin treated patients

with persistently elevated TG levels and other

CV risk factors

Seeking right to promote Vascepa as add-on to

statin therapy, not replace statin therapy

0%

5%

10%

15%

20%

25%

30%

LDL-C>130

mg/dL

TG>150

mg/dL

LDL-C and TG Prevalence in Adults

(U.S.)

Source: NHANES 2009-2012

15

67%

15% 16%

2%

0-149 mg/dL 150-199 mg/dL 200-499 mg/dL 500-2000 mg/dL

Large Underpenetrated Market Opportunities

150 Million

People

34 Million

People

36 Million

People3.8 Million

People

MARINEStudy

Only 3.6% Treated with Rx Meds

>100M People in Top 7 Global Markets for Initially-Targeted Indications

Source: Datamonitor and Archives of Internal Medicine, 2009;169(6):572-578

ANCHOR Study

Current

Indication*

REDUCE-IT

Outcomes Study

Includes Statin-treated

Patients in Ongoing

U.S. Adult Population Stratified Based on TG Levels

*Current indication for Vascepa; same as Lovaza®

TG levels:

U.S

. Ad

ult

Po

pu

lati

on

16

TGs

LDL-C

Vascepa: Potential to Redefine Lipid Management Therapies

Vascepa: New Paradigm in Cardiovascular Health

Traditional Cholesterol

Management Priority

Historically Limited TG

Treatment Options

New Generation

TG Lowering w/o LDL-C Increase(LDL-C decrease in ANCHOR vs. placebo)

LDL-C

HDL-C

LDL-CTGs

LIPID

PARAMETERS

KEY

TREATMENTS Statins, Niacin, Fibrates Fibrates, Other Prescription

Omega-3 which contain DHA

Amarin’s

FOCUS

Note: Arrows show direction only—not to scale

®

17

Vascepa: Lowers TGs and Other Lipid Markers

Very High TGs (≥500 mg/dL)

◼ All Primary Endpoints Achieved

◼ Favorable Safety and Tolerability Profile

◼ Favorable Effect on Other Endpoints (Total Cholesterol, VLDL-C)

-33%

-18%

-2%*

Phase 3 Results: MARINE Trial (4g/day dose)

Supported FDA Approved Indication (median placebo-adjusted data)

TG Non-HDL-C LDL-CTG >750

mg/dL

-45%

Note: median % change versus placebo at week 12 *=not significant

Ref: American Journal of Cardiology 2011; 108:682–690.

Apo B

-9%

Only reported adverse reaction across the clinical profile for

Vascepa with an incidence > 2% and greater than placebo in

Vascepa treated patients was arthralgia (2.3% for Vascepa,

1.0% for placebo)

18

Vascepa: Lowers TGs and Other Lipid Markers

High TGs (200 – 499 mg/dL) on Statin Therapy

◼ All Primary and Secondary Endpoints Achieved

◼ Favorable Safety and Tolerability Profile

◼ Favorable Effect on Other Endpoints (Total Cholesterol, VLDL-C)

Phase 3 Results: ANCHOR Trial (4g/day dose)

Indication not approved by FDA (median placebo-adjusted data)

TG Non-HDL-C LDL-C

Note: median % change versus placebo at week 12

Apo B

Ref: American Journal of Cardiology 2012;110:984-992

-22%

-14%

-6%

-9%

Only reported adverse reaction across the clinical profile

for Vascepa with an incidence > 2% and greater than

placebo in Vascepa treated patients was arthralgia

(2.3% for Vascepa, 1.0% for placebo)

19

Vascepa: Not Fish Oil, Pure EPA

Additional omega

6, 7 & 9 (100mg)

Other

Omega-3

Acid Ethyl

Esters

(60mg)

Ethyl DHA

(375 mg)

Ethyl EPA

(465 mg)

fatty

acids

~30 mg

Ethyl-EPA

(>960 mg)

APPROVED INDICATION

TG >500 mg/dL Marketed since 2004 (generic 2014) Marketed since 2013

LDL-C effect* Elevated LDL-C over 49% No Elevation (LDL-C reduction in ANCHOR study)

NON-HDL-C effect* Reduced 10.2% Reduced 17.7%

Total cholesterol effect* Reduced 8.0% Reduced 16.3%

Additional biomarkers*Limited, Variable or Not Characterized

in Label for Approved IndicationAdditional Beneficial Effects

Taste/eructation* Fishy Taste / Smell / Burp None

Atrial fibrillation warning* Added to package insert None

OTHER INDICATION POTENTIAL

TG >200 mg/dL and <500 mg/dLStudied, LDL-C Endpoint Not Achieved

(No Outcomes Study for Population)

Biomarker Endpoints Achieved

(Outcomes Benefit Being Studied in REDUCE-IT)

TG >150 mg/dL Not Studied Being Studied in REDUCE-IT

VASCEPA Icosapent Ethyl (Pure EPA)

*median placebo adjusted data and other info from FDA approved package inserts in TG >500 mg/dL patients

Earlier Generation Rx TherapyA Complex Mixture of Fatty Acids

20

Vascepa: Marketed in U.S. for Treating

Patients with Very High TGs (>500 mg/dL)

130 Amarin sales reps target high prescribing

physicians of earlier generation therapy Augmented since mid-2014 with co-promotion by

Kowa Pharmaceuticals America

Wholesale price $221 per month (120 capsules;

daily dose 4 capsules per day) $9 co-pay card for patients

Vascepa price at parity to generics of prior

generation omega-3 on net basis for most payors

>125M lives on tier 2

Competes on a basis of broad efficacy and

placebo-like safety and tolerability Works alone or as add-on to statin therapy

Doesn’t work against LDL-C lowering of statins

>29,000 prescribers

$-

$10

$20

$30

$40

$50

$60

2012 2013 2014

Vascepa Net Revenues (millions)

21

Vascepa Future Growth Potential

Early stages of marketing Vascepa for current indication Prior generation therapy grew to $1B drug based on same indication, despite

it increasing LDL-C

Applying lessons learned from first two years of launch for Amarin (Kowa’s co-

promotion is in early stages)

International expansion In February 2015, executed licensing partnership for Vascepa in China

‒ Received $15M up-front payment with the potential for $154M in additional

milestones plus tiered double digit royalties on future revenues

‒ Partner funding China regulatory approval

Reviewing other ex-US opportunities

Seeking broader opportunities to market Vascepa REDUCE-IT cardiovascular outcomes study

Pursuing judicial authority to promote truthful and non-misleading data to

physicians regarding ANCHOR study and EPA effects on CV risk while

REDUCE-IT is ongoing (1st Amendment suit)

22

Amarin Priorities for 2015

Grow Revenues from Current Vascepa Label

Leverage Vascepa clinical experience and expanded tier 2 coverage

Ensure focus and high sales call volume on highest potential prescribers

Increasing Vascepa experience and outreach from co-promotion partner (Kowa)

Tier 2 coverage for branded Lovaza disappears in 2015; generic Lovaza is expensive

Increase awareness of Vascepa efficacy, safety and tolerability profile

REDUCE-IT Outcomes Study

Complete enrollment in 2015

Prepare for interim look by independent DMC in 2016

Cost-Effectively Advance Other Opportunities

Evaluate additional Ex-US opportunities for Vascepa and consider strategic options

without losing focus on other priorities

Feasibility established for fixed-dose combination of Vascepa with leading statin

(AMR102); work to accelerate closer to completion of REDUCE-IT study

Further document Vascepa patient successes showing positive clinical effect of

switching patients to Vascepa from other TG lowering therapy

23

Capitalization Summary (in Millions)

As of March 31, 2015, except as noted

1 The total remaining cash payments due on this debt are $142.7 million which is a fixed amount and includes the

contractual interest paid quarterly at 10% of Vascepa revenues subject to quarterly maximum amounts. Lower carrying

value reported for accounting purposes per GAAP.2 Total principal of $150.0 million has put provisions for $31 million in Jan 2017 and $119 million in Jan 2019. Notes accrue

3.5% interest, paid semi-annually. Lower carrying value reported for accounting purposes per GAAP. 3 Includes 35.2 million common share equivalents issuable upon conversion of preferred shares issued in March 2015

Cash $161.2M

Debt Obligations

ROYALTY-LIKE DEBT1 $142.7M Carrying value $90.1M for accounting purposes

EXCHANGEABLE SENIOR NOTES2 $150.0M Carrying value $123.2M for accounting purposes

Common Stock and Equivalent Shares (Millions, Except per Share Amounts)

COMMON/PREFERRED SHARES3 212.2 Preferred shares mirror common but non-voting

OPTIONS 12.1 Average Exercise Price of $4.95

RESTRICTED STOCK UNITS 4.1

TOTAL IF ALL EXERCISED 228.4

TAX JURISDICTION (PRIMARY) Ireland12.5% Tax Rate

(Est. Global Blended Rate 15%)

24

Investment Highlights

Leading a New Paradigm in Cardiovascular Health Management

• Multi-billion dollar potential with REDUCE-IT outcomes study

• FDA approved for severe hypertriglyceridemia (TG >500 mg/dL)

• Multiple underserved patient populations with elevated TG levels

Large Global

Sales Potential

Differentiated Product • TG reduction -- no increase, or a decrease, in LDL-C

• Reductions in apo B, non-HDL-C, VLDL-C and total cholesterol

• Safety comparable to placebo

• Growing sales productivity; growing managed care coverage

• Phase 3 trials completed–all primary endpoints achieved

• Recently announced licensing partnership for Vascepa in China

• Outcomes study >93% enrolled and positioned for success

Positive Execution

• Grow revenues through specialty sales focus

• Seek broader promotional opportunities for Vascepa

• Cost-effectively advance other opportunities

Commercialization

Strategy

• Team with history of product development and commercial successes

• Direct sales team of 130 sales representatives, excluding sales managers

• Amarin team supplemented by 250 Kowa sales representatives

Experienced

Management

.

Leaders in Managing Lipids for

Improved Cardiovascular Health

INVESTOR PRESENTATION

June 2015

Nasdaq: AMRN