VAZKEPA (icosapent ethyl) is the first and only authorized treatment for its cardiovascular risk reduction indication1,2,3

VAZKEPA authorization for Great Britain follows recent VAZKEPA authorization for European Union

DUBLIN, Ireland and BRIDGEWATER, N.J., April 22, 2021 (GLOBE NEWSWIRE) -- Amarin Corporation plc (NASDAQ: AMRN) today announced that the Medicines and Healthcare Products Regulatory Agency (MHRA) has granted a Marketing Authorization for VAZKEPA (icosapent ethyl) as a treatment to reduce the risk of cardiovascular events in high cardiovascular risk statin-treated adult patients who have elevated triglycerides (≥150 mg/dL) and either established cardiovascular disease or diabetes, and at least one additional cardiovascular risk factor. The Great Britain Marketing Authorization for VAZKEPA applies to England, Scotland and Wales. Under the Brexit Northern Ireland agreement, the European centralized marketing authorization for the European Union covers Northern Ireland.

The MHRA’s license swiftly followed the European Commission (EC) marketing authorization of icosapent ethyl for the European Union as announced on March 30, 2021.3 Amarin’s understanding is that icosapent ethyl is among the first products to be submitted and licensed through the MHRA’s new ‘reliance’ route following the end of the Brexit transition period. Icosapent ethyl has been identified as a new active substance with likely multi-factorial mechanisms of action.1

The MHRA authorization for VAZKEPA is based on over a decade of development and testing of icosapent ethyl, including efficacy and safety data from the REDUCE-IT® cardiovascular outcomes study.2 REDUCE-IT evaluated more than 8,000 high-risk patients who despite having their cholesterol levels well controlled by statin therapy remained at significant risk of heart attack, stroke, or other major adverse cardiovascular events (MACE), including death. As published, patients in the REDUCE-IT study had a median follow-up period of nearly five years. Results from this study, in which all patients remained treated with statins (and with other contemporary therapies) and where half the patients received icosapent ethyl and the other half received placebo, demonstrated a 25% relative risk reduction (p1% more frequent than placebo): arthralgia (2% vs 1%) and oropharyngeal pain (1% vs 0.3%).

Key clinical effects of VASCEPA on major adverse cardiovascular events are included in the Clinical Studies section of the prescribing information for VASCEPA as set forth below:

Effect of VASCEPA on Time to First Occurrence of Cardiovascular Events in Patients with Elevated Triglyceride levels and Other Risk Factors for Cardiovascular Disease in REDUCE-IT

FULL U.S. FDA-APPROVED VASCEPA PRESCRIBING INFORMATIONCAN BE FOUND AT WWW.VASCEPA.COM.

Forward-Looking Statements This press release contains forward-looking statements, including statements about the potential of VAZKEPA (known as VASCEPA in the United States) to favorably affect cardiovascular risk in appropriate patients and about making VAZKEPA available throughout Europe to patients who are at risk of a cardiovascular event. These forward-looking statements are not promises or guarantees and involve substantial risks and uncertainties that may individually or together impact the matters herein and cause actual results, events and performance to differ materially from such forward-looking statements. Among the factors that could cause actual results to differ materially from those described or projected herein include the following: events that could impact future regulatory assessment, such as delays due to COVID-19 restrictions, later arising data, regulatory reviews and pricing assessments, and the successful implementation of commercialization plans or other information, events that could interfere with the grant or issuance of a patent, continued validity or enforceability of a patent; uncertainties associated with litigation generally and patent litigation specifically; Amarin's ability generally to maintain adequate patent protection and successfully enforce patent claims against third parties; and uncertainties associated generally with research and development and regulatory submissions, reviews, action dates and approvals. A further list and description of these risks, uncertainties and other risks associated with an investment in Amarin can be found in Amarin's filings with the U.S. Securities and Exchange Commission, including its most recent annual report on Form 10-K. Existing and prospective investors are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof. Amarin undertakes no obligation to update or revise the information contained in this press release, whether as a result of new information, future events or circumstances or otherwise.

Availability of Other Information About AmarinInvestors and others should note that Amarin communicates with its investors and the public using the company website (www.amarincorp.com), the investor relations website (investor.amarincorp.com), including but not limited to investor presentations and investor FAQs, Securities and Exchange Commission filings, press releases, public conference calls and webcasts. The information that Amarin posts on these channels and websites could be deemed to be material information. As a result, Amarin encourages investors, the media, and others interested in Amarin to review the information that is posted on these channels, including the investor relations website, on a regular basis. This list of channels may be updated from time to time on Amarin’s investor relations website and may include social media channels. The contents of Amarin’s website or these channels, or any other website that may be accessed from its website or these channels, shall not be deemed incorporated by reference in any filing under the Securities Act of 1933.

Amarin Contact InformationInvestor Inquiries:Investor RelationsAmarin Corporation plcIn U.S.: +1 (908) 719-1315 IR@amarincorp.com (investor inquiries)

Solebury Troutamarinir@troutgroup.com

Media Inquiries:CommunicationsAmarin Corporation plcIn U.S.: +1 (908) 892-2028 PR@amarincorp.com (media inquiries)

AMARIN, REDUCE-IT, VASCEPA and VAZKEPA are trademarks of Amarin Pharmaceuticals Ireland Limited. VAZKEPA is a registered trademark in Europe and other countries and regions and is pending registration in the United States.

1Summary of Product Characteristics Vazkepa – April 2021https://ec.europa.eu/health/documents/community-register/2021/20210326150935/anx_150935_en.pdf 2 Bhatt DL, Steg PG, Miller M, et al. Cardiovascular Risk Reduction with Icosapent Ethyl for Hypertriglyceridemia. N Engl J Med. 2019;380(1):11-22. 3 Union Register of medicinal products - Public health - European Commission. https://ec.europa.eu/health/documents/community-register/html/h1524.htm. Accessed April 22, 2021.4 2019 ESC/EAS guidelines for the management of dyslipidaemias: Lipid modification to reduce cardiovascular risk. Atherosclerosis. 2019;290:140-205.5 BHF/University of Birmingham calculated rates in partnership with UK statistical agencies: ONS/NRS/NISRA (2016-18 data)6 Fersia O, Bryant S, Nicholson R, et al. The impact of the COVID-19 pandemic on cardiology services. Heart. 2020;7:1359.7 American Heart Association. Heart Disease and Stroke Statistics—2020 Update: A Report From the American Heart Association. Circulation. 2020;141:e139–e596.8 Ganda OP, Bhatt DL, Mason RP, et al. Unmet need for adjunctive dyslipidemia therapy in hypertriglyceridemia management. J Am Coll Cardiol. 2018;72(3):330-343.9 Budoff M. Triglycerides and triglyceride-rich lipoproteins in the causal pathway of cardiovascular disease. Am J Cardiol. 2016;118:138-145.10 Toth PP, Granowitz C, Hull M, et al. High triglycerides are associated with increased cardiovascular events, medical costs, and resource use: A real-world administrative claims analysis of statin-treated patients with high residual cardiovascular risk. J Am Heart Assoc. 2018;7(15):e008740.11 Nordestgaard BG. Triglyceride-rich lipoproteins and atherosclerotic cardiovascular disease - New insights from epidemiology, genetics, and biology. Circ Res. 2016;118:547-563.12 Bhatt DL, Steg PG, Brinton E, et al., on behalf of the REDUCE-IT Investigators. Rationale and Design of REDUCE‐IT: Reduction of Cardiovascular Events with Icosapent Ethyl–Intervention Trial. Clin Cardiol. 2017;40:138-148.13 Bhatt DL, Steg PG, Miller M, et al., on behalf of the REDUCE-IT Investigators. Reduction in first and total ischemic events with icosapent ethyl across baseline triglyceride tertiles. J Am Coll Cardiol. 2019;74:1159-1161.