This Annual Report on Form 10-K contains forward-looking information based on our current expectations. Because our actual results may differ materially from any forward-looking statements that we make or that are made on our behalf, this section includes a discussion of important factors that could affect our actual future results, including, but not limited to, our capital resources, the progress and timing of our clinical programs, the safety and efficacy of our product candidates, regulatory filings and commercialization activities, the potential clinical benefits and market potential of our product candidates, commercial market estimates, future development efforts, patent protection, effects of healthcare reform, reliance on third parties, and other risks set forth below.

Risks Related to our Financial Position and Capital Requirements

We have a history of losses and anticipate that we will incur continued losses for the foreseeable future.

We have not been profitable in any of the last five fiscal years. For the fiscal years ended December 31, 2011, 2010, and 2009, we reported losses of approximately $69.1 million, $249.6 million, and $30.6 million, respectively. Substantially all of our operating losses resulted from costs incurred in connection with our research and development programs, from general and administrative costs associated with our operations, and from non-cash losses on changes in the fair value of warrant derivative liabilities. We expect to incur additional and increasing operating losses over the next several years. These losses, combined with expected future losses, have had and will continue to have an adverse effect on our cash resources, shareholders’ deficit and working capital. We expect our research and development expenses to significantly increase in connection with our proposed clinical outcomes study for AMR101 and any other studies for our product candidates. In addition, if we obtain regulatory approval for any of our product candidates, we may incur significant sales, marketing, in-licensing and outsourced manufacturing expenses, as well as continued research and development expenses. As a result, we expect to continue to incur significant and increasing operating losses for the foreseeable future. Because of the numerous risks and uncertainties associated with developing pharmaceutical products, we are unable to predict the extent of any future losses or when we will become profitable, if at all.

We have not generated any revenue from our product candidates and may never be profitable.

Our ability to become profitable depends upon our ability to generate revenue. Unless and until marketing approval is obtained from either the FDA or European Medicines Agency, which we refer to as the EMA, for any of our product candidates, or we are otherwise able to acquire rights to products or product candidates that have received regulatory approval or are at an advanced stage of development and can be readily commercialized, we may not be able to generate sufficient revenue to attain profitability. In addition, our ability to generate profits after any FDA or EMA approval of our product candidates is subject to our ability to contract for the manufacture of commercial quantities of our product candidates at acceptable cost levels and establish sales and marketing capabilities or identify and enter into one or more strategic collaborations to effectively market and sell any approved product candidate.

Even if one of our product candidates is approved for commercial sale, any approved product candidate may not gain market acceptance or achieve commercial success. In addition, we would anticipate incurring significant costs associated with commercializing any approved product. We may not achieve profitability soon after generating product sales, if ever. If we are unable to generate product revenues, we will not become profitable and may be unable to continue operations without continued funding.

Our ability to generate revenue depends on obtaining regulatory approvals for our products.

In order to successfully commercialize a product, we or our potential partners are required to conduct tests and successfully complete clinical trials needed in order to meet regulatory requirements and to obtain applicable regulatory approvals. The costs of developing and obtaining regulatory approvals for pharmaceutical products

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can be substantial. Our ability to commercialize any of our products in development is dependent upon the success of development efforts in clinical studies. If these clinical trials fail to produce satisfactory results, or if we are unable to maintain the financial and operational capability to complete these development efforts, we may be unable to generate revenues. Even if we obtain regulatory approvals, the timing or scope of any approvals may prohibit or reduce our ability to commercialize products successfully. For example, if the approval process takes too long, we may miss market opportunities and give other companies the ability to develop competing products or establish market dominance. Additionally, the terms of any approvals may not have the scope or breadth needed for us to commercialize products successfully.

Our historical financial results do not form an accurate basis for assessing our current business.

As a consequence of our decision in 2009 to focus on product development for cardiovascular indications and the discontinuation of development work related to other product candidates, our historical financial results do not form an accurate basis upon which investors should base their assessment of our business and prospects. In addition, we expect that our costs will increase substantially if we require additional clinical trials to obtain regulatory approval of AMR101, as a result of the initiation of the REDUCE-IT cardiovascular outcomes study and as we prepare for the commercialization of AMR101. Accordingly, our historical financial results reflect a substantially different business from that currently being conducted. In addition, we have not yet demonstrated an ability to obtain regulatory approval for or commercialize a product candidate. Consequently, any predictions about our future performance may not be as accurate as they could be if we had a history of successfully developing and commercializing pharmaceutical products.

We will require substantial additional resources to fund our operations and to develop our product candidates. If we cannot find additional capital resources, we will have difficulty in operating as a going concern and growing our business.

We currently operate with limited resources. At December 31, 2011, we had cash and cash equivalents of approximately $116.6 million. We believe that our current resources will be sufficient to fund our projected operations for the next twelve months, which projected operations contemplate not only working capital and general corporate needs but also commercial preparation of AMR101 and the continuation of the REDUCE-IT cardiovascular outcomes study. In order to commercialize AMR101, we must either develop a sales, marketing and distribution infrastructure or collaborate with third parties that have such experience. We plan to consider collaboration opportunities with larger pharmaceutical companies for the launch, marketing and sale of AMR101. Although from time to time we are in discussions with pharmaceutical companies regarding such collaboration, there can be no assurance that these discussions will result in any such transaction. Accordingly, we are also developing plans to launch, market and sell AMR101 in the United States on our own.

If we do not enter into a strategic collaboration in connection with the launch, marketing and sale of AMR101, we will likely need to raise additional capital to fully support these efforts. We will also need additional capital to fully complete our REDUCE-IT cardiovascular outcomes trial.

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Our future capital requirements will depend on many factors, including:

If we do not enter into a collaboration agreement to support the commercialization of AMR101, or if adequate funds are not available to us in amounts or on terms acceptable to us or on a timely basis, or at all, we may be required to terminate or delay our development efforts in support of our product candidates, or delay the advancement of the REDUCE-IT cardiovascular outcomes trial, or delay our establishment of sales and marketing capabilities or other activities that may be necessary to commercialize AMR101, in the event we obtain regulatory approval for this product candidate.

Continued negative economic conditions would likely have a negative impact on Amarin’s ability to obtain financing on acceptable terms.

While we may seek additional funding through public or private financings, we may not be able to obtain financing on acceptable terms, or at all. There can be no assurance that we will be able to access equity or credit markets in order to finance our current operations or expand development programs for any of our product candidates, or that there will not be a further deterioration in financial markets and confidence in economies. We may also have to scale back or further restructure our operations. If we are unable to obtain additional funding on a timely basis, we may be required to curtail or terminate some or all of our research or development programs.

Raising additional capital may cause dilution to our existing shareholders, restrict our operations or require us to relinquish rights.

We may seek additional capital through a combination of private and public equity offerings, debt financings and collaboration, strategic and licensing arrangements. To the extent that we raise additional capital through the sale of equity or convertible debt securities, your ownership interest will be diluted, and the terms may include liquidation or other preferences that adversely affect your rights as a shareholder.

As of December 31, 2011, there were warrants outstanding for the purchase of up to 21,106,363 American Depository Shares, or ADSs, each representing one of our ordinary shares, with a weighted average exercise price of $1.48 per share. We may issue additional warrants to purchase ADSs or ordinary shares in connection with any future financing we may conduct. In addition, on January 9, 2012, we issued $150 million in aggregate principal amount of 3.50% exchangeable senior notes due 2032, or the notes. The notes are exchangeable under certain circumstances into cash, our ADS, or a combination of cash and ADS, at our election, with an initial exchange rate of 113.4752 ADS per $1,000 principal amount of notes, if we elected physical settlement, the notes would initially be exchangeable into 17,021,280 ADS.

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Debt financing, if available, may involve agreements that include covenants limiting or restricting our ability to take specific actions such as incurring additional debt, making capital expenditures or declaring dividends. If we raise additional funds through collaboration, strategic alliance and licensing arrangements with third parties, we may have to relinquish valuable rights to our technologies or product candidates, or grant licenses on terms that are not favorable to us.

We are dependent upon the success of AMR101.

If development efforts for AMR101, including regulatory approval, are not successful for the MARINE, ANCHOR or any other indication, or if adequate demand for AMR101 is not generated, our business will be materially and adversely affected. Even if we are able to develop additional products from our research and development efforts, the development time cycle for products typically takes several years. This restricts our ability to respond to adverse business conditions for AMR101. If we are not successful in developing any future product or products, or if there is not adequate demand AMR101 or the market for such product develops less rapidly than we anticipate, we may not have the ability to effectively shift our resources to the development of alternative products. As a result, the limited range of products we develop could constrain our ability to generate revenues and achieve profitability.

Risks Related to the Development and Commercialization of our Product Candidates

There can be no assurance that our NDA submitted to the FDA seeking approval to market AMR101 will be approved and there can be no assurance that the FDA will complete its review of our NDA by the PDUFA date.

On September 26, 2011, we submitted an NDA to the FDA seeking approval to market AMR101 in the United States for use in the treatment of patients with very high triglyceride levels, or the MARINE indication, and the FDA has assigned a Prescription Drug User Fee Act, or PDUFA, date of July 26, 2012 for the completion of its review. The PDUFA date is the goal date for the FDA to complete its review of the NDA. However, there can be no assurance that the FDA will complete its review of the NDA by this date. The FDA may deny approval of the application and require additional testing or data. In the event the FDA takes any such action, such actions would have a material adverse effect on our operations and financial condition.

Our SPA agreements with the FDA are not guarantees of FDA approval of AMR101 for the subject indications.

An SPA agreement is an evaluation by the FDA of a protocol with the goal of reaching an agreement that the Phase 3 trial protocol design, clinical endpoints, and statistical analyses are acceptable to support regulatory approval of the drug product candidate with respect to effectiveness for the indication studied. The MARINE trial and ANCHOR trial were each conducted under an SPA with the FDA. The REDUCE-IT trial is also being conducted under an SPA with the FDA. The FDA agreed that, based on the information we submitted to the agency, the design and planned analysis of the MARINE and ANCHOR trials are adequate to support use of the studies as the primary basis for approval with respect to effectiveness. An SPA is generally binding upon the FDA except in limited circumstances, such as if the FDA identifies a substantial scientific issue essential to determining safety or efficacy is identified after the study begins, or if the study sponsor fails to follow the protocol that was agreed upon with the FDA. There is no assurance that the FDA will not identify a scientific issue and deem either or both of our SPAs no longer binding. Moreover, any change to a study protocol after agreement with the FDA is reached can invalidate an SPA. While we amended the protocol for the ANCHOR trial after the initial SPA evaluation was completed, we obtained the FDA’s evaluation of, and agreement to, the amendment. If, for example, the FDA does not consider the applicable SPA to be binding during its review of our regulatory approval applications, or if the FDA determines that we did not follow the SPAs appropriately, the agency could assert that additional studies or data are required to support approval of the application.

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Even if we obtain marketing approval for AMR101 in the United States, there can be no assurance as to the final indication or indications approved by the FDA, and the commercial value to us of any approved indication may be smaller than we anticipate.

There can be no assurance as to the final indication approved by the FDA, in the event that marketing approval is obtained. Even if marketing approval is obtained, the number of actual patients with the condition included in such approved indication may be smaller than we anticipate. For example, the FDA could approve the MARINE indication and not the ANCHOR indication. Even if we obtain marketing approval, the FDA may impose restrictions on the product’s conditions for use, distribution or marketing and in some cases may impose ongoing requirements for post-market surveillance, post-approval studies or clinical trials. If any such approved indication is narrower than we anticipate, the market potential for our product candidate would suffer.

Even if we obtain marketing approval for AMR101 in the United States, it may fail to achieve the degree of market acceptance by physicians, patients, healthcare payors and others in the medical community necessary for commercial success.

If AMR101 receives marketing approval, it may nonetheless fail to gain sufficient market acceptance by physicians, patients, healthcare payors and others in the medical community. Gaining market acceptance for our product may be particularly difficult. If AMR101 does not achieve an adequate level of acceptance, we may not generate significant product revenues and we may not become profitable. The degree of market acceptance of our product candidates, if approved for commercial sale, will depend on a number of factors, including:

Even if our products are approved, we may not be able to compete effectively against our competitors’ pharmaceutical products.

The pharmaceutical industry is highly competitive. If we are successful in completing the development of any of our products, we may face competition to the extent other pharmaceutical companies have on the market or are able to develop products for the treatment of similar indications. Potential competitors in this market include companies with greater resources and name recognition than we have. Furthermore, to the extent we are able to acquire or develop additional marketable products in the future, such products will compete with a variety of other products within the United States or elsewhere, possibly including established drugs and major brand names. Competitive factors, including generic competition, could force us to lower prices or could result in reduced sales. In addition, new products developed by others could emerge as competitors to our future products. Products based on new technologies or new drugs could render our products obsolete or uneconomical.

The success of our future products will also depend in large part on the willingness of physicians to prescribe these products to their patients. Our future products may compete against products that have achieved broad recognition and acceptance among medical professionals. In order to achieve an acceptable level of prescriptions for our future products, we must be able to meet the needs of both the medical community and end users with respect to cost, efficacy and other factors.

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Our potential competitors both in the United States and Europe include large, well-established pharmaceutical companies, specialty pharmaceutical sales and marketing companies and specialized cardiovascular treatment companies. These companies include GlaxoSmithKline plc, which currently markets Lovaza, a prescription-only omega-3 fatty acid indicated for patients with very high triglycerides, and Abbott Laboratories, which currently markets Tricor and Trilipix for the treatment of very high triglycerides and mixed dyslipidemia. In March 2011, Pronova BioPharma Norge AS, which owns the patents for Lovaza, entered into an agreement with Apotex Corp. and Apotex Inc. to settle their patent litigation in the United States related to Lovaza. Pursuant to the terms of the settlement agreement, Pronova granted Apotex a license to enter the United States market with a generic version of Lovaza in the first quarter of 2015, or earlier depending on circumstances. We expect Apotex to compete against us as well. Other companies are also seeking to introduce generic versions of Lovaza. These competitors have greater resources than we do, including financial, product development, marketing, personnel and other resources.

In addition, we are aware of other pharmaceutical companies that are developing products that, if approved, would compete with AMR101. These include a free fatty acid form of omega-3 (comprised of 55% EPA and 20% DHA) which is being developed by Omthera Pharmaceuticals, which completed enrollment in a Phase 3 clinical trial in November 2011 and has announced that it expects to disclose initial top-line data by April 2012, and Trygg Pharma, which has completed a Phase 3 study of an omega-3 based drug candidate for hypertriglyceridemia, but we believe Trygg has not yet announced results from that study. In addition, Acasti Pharma, a subsidiary of Neptune Technologies & Bioresources Inc., announced in late 2011 the enrollment of its Phase 2 clinical trial to assess the safety and efficacy of its omega-3 prescription drug candidate for the treatment of hypertriglceridemia. We believe Resolvyx Pharmaceuticals and Catabasis Pharmaceuticals are also developing potential treatments for hypertriglceridemia based on omega-3 fatty acids, but neither has initiated a Phase 2 clinical trial of its product.

AMR101, if approved, will also face competition from dietary supplement companies marketing naturally occurring omega-3 fatty acids as nutritional supplements.

Our current lead product candidate is a prescription-only omega-3 fatty acid. Omega-3 fatty acids are also marketed by other companies as non-prescription dietary supplements. As a result, our lead product candidate, if approved, would be subject to non-prescription competition and consumer substitution.

Our current lead product candidate, AMR101, is a prescription-only omega-3 fatty acid. Mixtures of omega-3 fatty acids are naturally occurring substances in various foods, including fatty fish. Omega-3 fatty acids are also marketed by others as non-prescription dietary supplements. We believe the pharmaceutical grade purity of AMR101, if approved, will have a superior therapeutic profile to naturally occurring omega-3 fatty acids and dietary supplements. However, we cannot be sure physicians will view AMR101, if approved, as superior. To the extent the price of AMR101, if approved, is significantly higher than the prices of commercially available omega-3 fatty acids marketed by other companies as dietary supplements, physicians may recommend these commercial alternatives instead of writing prescriptions for AMR101 or patients may elect on their own to take commercially available omega-3 fatty acids. Either of these outcomes may adversely impact our results of operations by limiting how we price our product and limiting the revenue we receive from the sale of AMR101.

To maximize the commercial potential of AMR101, if approved, we may need to find collaborative partners to help market and sell the product.

To commercialize AMR101, we must either develop a sales, marketing and distribution infrastructure or collaborate with third parties that have such experience. We plan to consider collaboration opportunities with larger pharmaceutical companies for the launch, marketing and sale of AMR101. If we do complete such a collaboration agreement, we will be reliant on one or more of these strategic partners to generate revenue on our behalf.

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We may not be successful in finding a collaborative partner to help market and sell our products, or may be delayed in doing so, in which case we would not receive revenue or royalties on the timeframe and to the extent that we currently anticipate. We face significant competition in seeking appropriate collaborators and these collaborations are complex and time-consuming to negotiate and document. We may not be able to negotiate collaborations on acceptable terms, or at all. If that were to occur, we may have to curtail the development of a particular product candidate, reduce or delay its development program or one or more of our other development programs, delay its potential commercialization or reduce the scope of our sales or marketing activities, or increase our expenditures and undertake development or commercialization activities at our own expense. If we elect to increase our expenditures to fund development or commercialization activities on our own, we will need to obtain additional capital, which may not be available to us on acceptable terms, or at all. If we cannot raise sufficient funds, we will not be able to bring our product candidates to market effectively and generate as much product revenue as we could under a collaboration.

If we are unable to establish sales and marketing capabilities or enter into agreements with third parties to sell and market AMR101, we may not be successful in commercializing AMR101 on our own, if and when AMR101 is approved.

To achieve commercial success for any approved product, we must either develop a sales and marketing organization or outsource these functions to third parties. Until such time as we complete a strategic transaction with a third party to market and sell AMR101, if ever, we are continuing to develop plans to launch, market and sell AMR101 on our own. This includes making preparations for securing a sufficient commercial supply of AMR101 and expanding sales and marketing capabilities and would require that we build a substantial commercialization infrastructure in order to compete with larger companies with established marketing and sales capabilities. We do not have a sales or marketing infrastructure and have no experience in the sale, marketing or distribution of pharmaceutical products. There are risks involved with both establishing our own sales and marketing capabilities and entering into arrangements with third parties to perform these services. For example, recruiting and training a sales force is expensive and time consuming and could delay any product launch. If the commercial launch of a product candidate for which we recruit a sales force and establish marketing capabilities is delayed or does not occur for any reason, we would have prematurely or unnecessarily incurred these commercialization expenses. This may be costly, and our investment would be lost if we cannot retain or reposition our sales and marketing personnel.

Factors that may inhibit our efforts to commercialize our products on our own include:

If we enter into arrangements with third parties to perform sales, marketing and distribution services, our product revenues or the profitability of these product revenues to us are likely to be lower than if we were to market and sell any products that we develop ourselves. In addition, we may not be successful in entering into arrangements with third parties to sell and market our product candidates or doing so on terms that are favorable to us. We likely will have little control over such third parties, and any of them may fail to devote the necessary resources and attention to sell and market our products effectively. If we do not establish sales and marketing capabilities successfully, either on our own or in collaboration with third parties, we will not be successful in commercializing our product candidates.

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If approved, our products will be subject to extensive post-approval government regulation.

Once a product candidate receives FDA marketing approval, numerous post-approval requirements apply. Among other things, the holder of an approved NDA is subject to periodic and other monitoring and reporting obligations enforced by the FDA and other regulatory bodies, including obligations to monitor and report adverse events and instances of the failure of a product to meet the specifications in the approved application. Application holders must also submit advertising and other promotional material to regulatory authorities and report on ongoing clinical trials.

With respect to sales and marketing activities by our partners, advertising and promotional materials must comply with FDA rules in addition to other applicable federal and local laws in the United States and in other countries. In the United States, the distribution of product samples to physicians must comply with the requirements of the U.S. Prescription Drug Marketing Act. Manufacturing facilities remain subject to FDA inspection and must continue to adhere to the FDA’s current good manufacturing practice requirements. Application holders must obtain FDA approval for product and manufacturing changes, depending on the nature of the change. We may also be subject, directly or indirectly through our customers and partners, to various fraud and abuse laws, including, without limitation, the U.S. Anti-Kickback Statute, U.S. False Claims Act, and similar state laws, which impact, among other things, our proposed sales, marketing, and scientific/educational grant programs. If we participate in the U.S. Medicaid Drug Rebate Program, the Federal Supply Schedule of the U.S. Department of Veterans Affairs, or other government drug programs, we will be subject to complex laws and regulations regarding reporting and payment obligations. All of these activities are also potentially subject to U.S. federal and state consumer protection and unfair competition laws. Similar requirements exist in many of these areas in other countries.

Depending on the circumstances, failure to meet these post-approval requirements can result in criminal prosecution, fines or other penalties, injunctions, recall or seizure of products, total or partial suspension of production, denial or withdrawal of pre-marketing product approvals, or refusal to allow us to enter into supply contracts, including government contracts. In addition, even if we or our potential partners comply with FDA and other requirements, new information regarding the safety or effectiveness of a product could lead the FDA to modify or withdraw a product approval. Adverse regulatory action, whether pre- or post-approval, can potentially lead to product liability claims and increase our product liability exposure. We or our potential partners must also compete against other products in qualifying for coverage and reimbursement under applicable third party payment and insurance programs.

The FDA and other regulatory agencies strictly regulate the promotional claims that may be made about prescription products. If we are found to have improperly promoted off-label uses, we may become subject to significant fines and other liability.

The FDA and other regulatory agencies strictly regulate the promotional claims that may be made about prescription products. In particular, a product may not be promoted for uses that are not approved by the FDA or such other regulatory agencies as reflected in the product’s approved labeling. If we receive marketing approval for AMR101, physicians may nevertheless prescribe AMR101 to their patients in a manner that is inconsistent with the approved label. If we are found to have promoted such off-label uses, we may become subject to significant government fines and other related liability. For example, the Federal government has levied large civil and criminal fines against companies for alleged improper promotion and has enjoined several companies from engaging in off-label promotion. The FDA has also requested that companies enter into consent decrees or permanent injunctions under which specified promotional conduct is changed or curtailed.

Our cardiovascular outcomes study, REDUCE-IT, may take longer than we anticipate to be determined by the FDA to be substantially underway, which could delay FDA review and approval of the ANCHOR indication and cost more than we expect. The FDA may not approve our request to consider the indication studied in the ANCHOR trial in conjunction with the FDA’s review of the indication studied in the MARINE trial.

Based on our communications with the FDA, in order to obtain FDA marketing approval of a separate indication for the use of AMR101 in the treatment of patients with high triglyceride levels who are also on statin

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therapy for elevated LDL-cholesterol levels (which we refer to as mixed dyslipidemia), or the ANCHOR indication, we believe that we must first obtain approval in the MARINE indication and have a cardiovascular outcomes study substantially underway at the time of the NDA submission. In August 2011, we reached a agreement with the FDA on an SPA for the design of the REDUCE-IT cardiovascular outcomes study of AMR101, and we began dosing patients in December 2011. In the event we do not receive approval of the MARINE indication or experience delays in initiating or achieving substantial enrollment for REDUCE-IT or the FDA requires that we enroll more patients, our filing of an sNDA seeking approval of the ANCHOR indication will be delayed. We currently intend to file an sNDA seeking approval of the indication studied in the ANCHOR trial after we receive FDA marketing approval for the MARINE indication and after we believe the REDUCE-IT study will be determined to be substantially underway by the FDA.

The REDUCE-IT cardiovascular trial may fail to achieve its clinical endpoints, and the long-term clinical results of AMR101 may not be consistent with the clinical results we observed in our Phase 3 pivotal trials.

In accordance with the SPA for our MARINE and ANCHOR trials, efficacy was evaluated in these trials compared to placebo at twelve weeks. No placebo-controlled studies have been conducted regarding the long-term effect of AMR101 on lipids and no outcomes study has been conducted evaluating AMR101. Outcomes studies of certain other lipid modifying therapies have failed to achieve the endpoints of such studies. There can be no assurance that the endpoints of the REDUCE-IT cardiovascular outcomes study will be achieved or that the lipid modifying effects of AMR101 in REDUCE-IT or any other study of AMR101 will not be subject to variation beyond twelve weeks. If the REDUCE-IT trial fails to achieve its clinical endpoints or if the results of these long-term studies are not consistent with the 12-week clinical results it could prevent us from expanding the label of any approved product or even call into question the efficacy of any approved product.

We may not be successful in developing or marketing future products if we cannot meet the extensive regulatory requirements of the FDA and other regulatory agencies for quality, safety and efficacy.

The success of our research and development efforts is dependent in part upon our ability, and the ability of our partners or potential partners, to meet regulatory requirements in the jurisdictions where we or our partners or potential partners ultimately intend to sell such products once approved. The development, manufacture and marketing of pharmaceutical products are subject to extensive regulation by governmental authorities in the United States, the European Union, Japan and elsewhere. In the United States, the FDA generally requires pre-clinical testing and clinical trials of each drug to establish its safety and efficacy and extensive pharmaceutical development to ensure its quality before its introduction into the market. Regulatory authorities in other jurisdictions impose similar requirements. The process of obtaining regulatory approvals is lengthy and expensive and the issuance of such approvals is uncertain. The commencement and rate of completion of clinical trials and the timing of obtaining marketing approval from regulatory authorities may be delayed by many factors, including:

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Even if we obtain positive results from early stage pre-clinical or clinical trials, we may not achieve the same success in future trials. Similarly, positive results from studies in Japan of a product containing the same active ingredient in AMR101 may not be predictive of success for AMR101 in trials outside of Japan. Clinical trials that we or potential partners conduct may not provide sufficient safety and efficacy data to obtain the requisite regulatory approvals for product candidates. The failure of clinical trials to demonstrate safety and efficacy for our desired indications could harm the development of that product candidate as well as other product candidates, and our business and results of operations would suffer. For example, the efficacy results of our AMR101 Phase 3 clinical trials for the treatment of Huntington’s disease were negative. As a result, we stopped development of that product candidate, we revised our clinical strategy and shifted our focus to develop AMR101 for use in the treatment of cardiovascular disease.

Any approvals that are obtained may be limited in scope, may require additional post-approval studies or may require the addition of labeling statements focusing on product safety that could affect the commercial potential for our product candidates. Any of these or similar circumstances could adversely affect our ability to earn revenues from the sale of such products. Even in circumstances where products are approved by a regulatory body for sale, the regulatory or legal requirements may change over time, or new safety or efficacy information may be identified concerning a product, which may lead to the withdrawal of a product from the market or similar use restrictions. The discovery of previously unknown problems with a product or in connection with the manufacturer of products may result in restrictions on that product or manufacturer, including withdrawal of the product from the market, which would have a negative impact on our potential revenue stream.

Legislative or regulatory reform of the health care system in the United States and foreign jurisdictions may affect our ability to profitably sell our products, if approved.

Our ability to commercialize our future products successfully, alone or with collaborators, will depend in part on the extent to which coverage and reimbursement for the products will be available from government and health administration authorities, private health insurers and other third-party payors. The continuing efforts of the U.S. and foreign governments, insurance companies, managed care organizations and other payors of health care services to contain or reduce health care costs may adversely affect our ability to set prices for our products which we believe are fair, and our ability to generate revenues and achieve and maintain profitability.

Specifically, in both the United States and some foreign jurisdictions, there have been a number of legislative and regulatory proposals to change the health care system in ways that could affect our ability to sell our products profitably. For example, the Patient Protection and Affordable Care Act, as amended by the Health Care and Education Reconciliation Act, or collectively the PPACA, enacted in March 2010, substantially changes the way healthcare is financed by both governmental and private insurers. Among other cost-containment measures, PPACA establishes:

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We expect further federal and state proposals and health care reforms to continue to be proposed by legislators, which could limit the prices that can be charged for the products we develop and may limit our commercial opportunity.

The continuing efforts of government and other third-party payors to contain or reduce the costs of health care through various means may limit our commercial opportunity. It will be time consuming and expensive for us to go through the process of seeking coverage and reimbursement from Medicare and private payors. Our products may not be considered cost effective, and government and third-party private health insurance coverage and reimbursement may not be available to patients for any of our future products or sufficient to allow us to sell our products on a competitive and profitable basis. Our results of operations could be adversely affected by PPACA and by other health care reforms that may be enacted or adopted in the future. In addition, increasing emphasis on managed care in the United States will continue to put pressure on the pricing of pharmaceutical products. Cost control initiatives could decrease the price that we or any potential collaborators could receive for any of our future products and could adversely affect our profitability.

In some foreign countries, including major markets in the European Union and Japan, the pricing of prescription pharmaceuticals is subject to governmental control. In these countries, pricing negotiations with governmental authorities can take 6 to 12 months or longer after the receipt of regulatory marketing approval for a product. To obtain reimbursement or pricing approval in some countries, we may be required to conduct a pharmacoeconomic study that compares the cost-effectiveness of our product candidates to other available therapies. Such pharmacoeconomic studies can be costly and the results uncertain. Our business could be harmed if reimbursement of our products is unavailable or limited in scope or amount or if pricing is set at unsatisfactory levels.

As we evolve from a company primarily involved in research and development to a company also potentially involved in commercialization, we may encounter difficulties in managing our growth and expanding our operations successfully.

Although certain of our employees have commercialization experience, as a company we currently have no sales, marketing or distribution capabilities. Accordingly, as we advance AMR101 through the development stage towards commercialization, we will need to expand our organization, including marketing and sales capabilities or contract with third parties to provide these capabilities for us, which will be expensive and time consuming. Any failure or delay in the development of our internal sales, marketing and distribution capabilities would adversely impact the commercialization of AMR101 in the event it receives regulatory approval. If we are not successful in commercializing AMR101 or our other product candidates in the event they receive regulatory approval, our future product revenue will suffer and we may incur significant additional losses.

As our operations expand, we expect that we will need to manage additional relationships with various collaborative partners, suppliers and other third parties. Future growth will impose significant added responsibilities on members of management. Our future financial performance and our ability to commercialize AMR101 and to compete effectively will depend, in part, on our ability to manage any future growth effectively. To that end, we must be able to manage our development efforts effectively, and hire, train and integrate additional management, administrative and sales and marketing personnel. We may not be able to accomplish these tasks, and our failure to accomplish any of them could prevent us from successfully growing our company.

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Risks Related to our Reliance on Third Parties

Our supply of product for commercial supply and clinical trials is dependent upon relationships with third party manufacturers and key suppliers.

We have no in-house manufacturing capacity and rely on contract manufacturers for our clinical and commercial product supply. We cannot assure you that we will successfully manufacture any product we may develop, either independently or under manufacturing arrangements, if any, with our third party manufacturers. Moreover, if any manufacturer should cease doing business with us or experience delays, shortages of supply or excessive demands on their capacity, we may not be able to obtain adequate quantities of product in a timely manner, or at all.

Any manufacturing problem, natural disaster affecting manufacturing facilities, or the loss of a contract manufacturer could be disruptive to our operations and result in lost sales. Additionally, we will be reliant on third parties to supply the raw materials needed to manufacture our potential products. Any reliance on suppliers may involve several risks, including a potential inability to obtain critical materials and reduced control over production costs, delivery schedules, reliability and quality. Any unanticipated disruption to future contract manufacture caused by problems at suppliers could delay shipment of products, increase our cost of goods sold and result in lost sales. If our suppliers were unable to supply us with adequate supply of ethyl-EPA it would have a material adverse affect on our ability to commercialize AMR101.

We currently purchase all of our supply of the bulk compound (ethyl-EPA), which constitutes the only active pharmaceutical ingredient, or API, of AMR101, from a single supplier with a single manufacturing facility, Nisshin Pharma, or Nisshin, located in Japan. Nisshin currently obtains its supply of the key raw material to manufacture API from another third party single source of supply. While we have contractual freedom to source the API for AMR101 elsewhere and have entered into supply agreements with additional suppliers who rely on other third party suppliers of the key raw material to manufacture the API for AMR101, Nisshin is the only supplier submitted for approval with our pending NDA to the FDA. Further, our agreements with our suppliers typically include minimum purchase obligations. Moreover, there is no guarantee that additional other suppliers with which we have contracted to supply API will be qualified to manufacture the product to our specifications or that these and any future suppliers will have the manufacturing capacity to meeting anticipated demand for AMR101. We cannot assure you that we can contract with any future manufacturer on acceptable terms or that any such alternative supplier will not require capital investment from us in order for them to meet our requirements.

The manufacture and packaging of pharmaceutical products such as AMR101 are subject to FDA requirements and those of similar foreign regulatory bodies. If we or our third party manufacturers fail to satisfy these requirements, our product development and commercialization efforts may be materially harmed.

The manufacture and packaging of pharmaceutical products, such as AMR101, are regulated by the FDA and similar foreign regulatory bodies and must be conducted in accordance with the FDA’s current good manufacturing practices and comparable requirements of foreign regulatory bodies. There are a limited number of manufacturers that operate under these current good manufacturing practices regulations who are both capable of manufacturing AMR101 and willing to do so. Failure by us or our third party manufacturers to comply with applicable regulations, requirements, or guidelines could result in sanctions being imposed on us, including fines, injunctions, civil penalties, failure of regulatory authorities to grant marketing approval of our products, delays, suspension or withdrawal of approvals, license revocation, seizures or recalls of product, operating restrictions and criminal prosecutions, any of which could significantly and adversely affect our business. For example, our NDA filed with the FDA has only one supplier of API for AMR101, Nisshin, and Nisshin has plans to expand it capacity to supply API to us by building a new facility. If Nisshin facilities used for the manufacturing and testing of AMR101 API are delayed in passing FDA pre-approval inspection to ensure substantial compliance with current good manufacturing practices and other FDA standards, or if we are not able to manufacture

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AMR101 to required specifications through Nisshin, our FDA marketing approval of AMR101 may be delayed, we may be delayed in launching the product and our anticipated future revenues and financial results may be materially adversely affected. The same requirements and risks are applicable to the suppliers of the key raw material used to manufacture the API for AMR101.

Changes in the manufacturing process or procedure, including a change in the location where the product is manufactured or a change of a third party manufacturer, may require prior FDA review and approval of the manufacturing process and procedures in accordance with the FDA’s current good manufacturing practices. Any new facility is subject to a pre-approval inspection by the FDA and would again require us to demonstrate product comparability to the FDA. There are comparable foreign requirements. This review may be costly and time consuming and could delay or prevent the launch of a product. For example, after FDA approval of AMR101, we plan to file a supplemental NDA to add new manufacturing facilities from other third party suppliers to manufacture API for AMR101. If these third parties cannot establish, to the satisfaction of the FDA, that they are in substantial compliance with current good manufacturing practices, and that the products manufactured at the new site meet FDA requirements, we may not be able to manufacture API from that site, our supply of API for AMR101 may be delayed, and our anticipated future revenues and financial results may be materially adversely affected.

Furthermore, in order to obtain approval of our products, including AMR101, by the FDA and foreign regulatory agencies, we will be required to consistently produce the active pharmaceutical ingredient and the finished product in commercial quantities and of specified quality on a repeated basis and document our ability to do so. This requirement is referred to as process validation. We have completed a validation process for the API for AMR101 at Nisshin, but have not yet done so at any other contract supplier. Each of our potential API suppliers use a different method to manufacture API, which has the potential to increase the risk to us that our manufacturers will meet applicable regulatory requirements. We also need to complete process validation on the finished product in the packaging we propose for commercial sales. This includes testing of stability, measurement of impurities and testing of other product specifications by validated test methods. If the FDA does not consider the result of the process validation or required testing to be satisfactory, we may not obtain approval to launch the product or approval, launch or commercial supply after launch may be delayed.

The FDA and similar foreign regulatory bodies may also implement new standards, or change their interpretation and enforcement of existing standards and requirements, for manufacture, packaging or testing of products at any time. If we are unable to comply, we may be subject to regulatory, civil actions or penalties which could significantly and adversely affect our business.

During 2012, we intend to increase our purchases of API and finished capsules of AMR101 in preparation of commercial launch. We plan to make certain of these purchases prior to NDA approval with the aim to further expand purchase levels of supply after NDA approval. We may elect to make API purchases from certain of our suppliers after we are satisfied that the material they produce and their facilities are qualified. However, in the event that we make such purchases, we will not be able to use such material for commercial sale until the sNDA for the applicable supplier is approved by the FDA. Similarly, if we are not compliant with other regulations with regard to this intended purchase of supply, our launch may be delayed.

We rely on third parties to conduct our clinical trials, and those third parties may not perform satisfactorily, including failing to meet established deadlines for the completion of such clinical trials.

Our reliance on third parties for clinical development activities reduces our control over these activities. However, if we sponsor clinical trials, we are responsible for ensuring that each of our clinical trials is conducted in accordance with the general investigational plan and protocols for the trial. Moreover, the FDA requires us to comply with standards, commonly referred to as good clinical practices, for conducting, recording, and reporting the results of clinical trials to assure that data and reported results are credible and accurate and that the rights, integrity and confidentiality of trial participants are protected. Our reliance on third parties does not relieve us of these responsibilities and requirements. Furthermore, these third parties may also have relationships with other entities, some of which may be our competitors. If these third parties do not successfully carry out their

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contractual duties or meet expected deadlines, we may be delayed in obtaining regulatory approvals for our product candidates and may be delayed in our efforts to successfully commercialize our product candidates for targeted diseases.

Risks Related to our Intellectual Property and Regulatory Exclusivity

We are dependent on patents, proprietary rights and confidentiality.

Because of the significant time and expense involved in developing new products and obtaining regulatory approvals, it is very important to obtain patent and trade secret protection for new technologies, products and processes. Our ability to successfully implement our business plan will depend in large part on our ability to:

We currently have no issued patents that directly apply to the use of AMR101 for hypertriglyceridemia, hyperlipidemia or cardiovascular therapy in the United States or Europe. Although we are currently prosecuting a number of patent applications in this area, we will also rely upon trade secrets and know-how to retain our competitive position. When deemed appropriate, we intend to vigorously enforce our patent protection and intellectual property rights. We file patent applications either on a country-by-country basis or by using the European or international patent cooperation treaty systems.

We may be dependent in some cases upon third party licensors to pursue filing, prosecution and maintenance of patent rights or applications owned or controlled by those parties. It is possible that third parties will obtain patents or other proprietary rights that might be necessary or useful to us. In cases where third parties are first to invent a particular product or technology, or first to file after various provisions of the America Invents Act of 2011 go into effect on March 16, 2013, it is possible that those parties will obtain patents that will be sufficiently broad so as to prevent us from utilizing such technology.

Although we intend to make reasonable efforts to protect our current and future intellectual property rights and to ensure that any proprietary technology we acquire or develop does not infringe the rights of other parties, we may not be able to ascertain the existence of all potentially conflicting claims. Therefore, there is a risk that third parties may make claims of infringement against our current or future products or technologies. In addition, third parties may be able to obtain patents that prevent the sale of our current or future products or require us to obtain a license and pay significant fees or royalties in order to continue selling such products.

We may in the future discover the existence of products that infringe upon patents that we own or that have been licensed to us. Although we intend to protect our trade secrets and proprietary know-how through confidentiality agreements with our manufacturers, employees and consultants, we may not be able to prevent parties subject to such confidentiality agreements from breaching these agreements or third parties from independently developing or learning of our trade secrets.

We anticipate that competitors may from time to time oppose our efforts to obtain patent protection for new technologies or to submit patented technologies for regulatory approvals. Competitors may seek to oppose patent applications to delay the approval process or to challenge granted patents, even if the opposition or challenge has little or no merit. Patent oppositions proceedings and challenges are generally highly technical, time consuming and expensive to pursue. Were we to be subject to one or more patent oppositions or challenges, that effort could consume substantial time and resources, with no assurances of success, even when holding an issued patent.

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There can be no assurance that any of our pending patent applications relating to AMR101 or its use will issue as patents.

We have filed and are prosecuting numerous families of patent applications in the United States and internationally with claims designed to protect the proprietary position of AMR101. For certain of these patent families, we have filed multiple patent applications. Collectively the patent applications include numerous independent claims and dependent claims. Several of our patent applications contain claims that are based upon what we believe are unexpected and positive findings from the MARINE and ANCHOR trials. If granted, many of the resulting granted patents would expire in 2030 or beyond. However, no assurance can be given that any of our patent applications will be granted or, if they grant, that they will prevent competitors from competing with AMR101. Securing additional patent protection for a product is a complex process involving many legal and factual questions. The patent applications we have filed in the United States and internationally are at varying stages of examination, the timing of which is outside our control. The process to getting a patent granted can be lengthy and claims initially submitted are often modified in order to satisfy the requirements of the patent office. This process includes written and public communication with the patent office. The process can also include direct discussions with the patent examiner. There can be no assurance that the patent office will accept our arguments with respect to any patent application or with respect to any claim therein. The timing of the patent review process is independent of and has no effect on the timing of the FDA’s review of our NDA. To our knowledge, the U.S. Patent and Trademark Office or other international patent offices have not yet commenced examining certain of these applications. While examination of certain of these applications is anticipated during 2012, we cannot predict the timing or results of such examination. In addition, we may elect to submit, or the patent office may require, additional evidence to support certain of the claims we are pursuing. Providing such additional evidence could result in us incurring additional costs. We cannot be certain what commercial value any granted patent in our patent estate will provide to us.

If AMR101 is not granted new chemical entity exclusivity protection from the FDA our business may be materially harmed.

Under sections 505(c)(3)(E)(ii) and 505(j)(5)(F)(ii) of the Food Drug and Cosmetic Act, or FDCA, as amended by the Drug Price Competition and Patent Term Restoration Act of 1984, as amended, or the Hatch-Waxman Amendments, a new chemical entity that is granted regulatory approval may be eligible for five years of marketing exclusivity in the United States following regulatory approval. A drug can be classified as a new chemical entity if the FDA has not previously approved any other drug containing the same active moiety.

We believe that the active pharmaceutical ingredient in AMR101, at least 96% ethyl-EPA, may be considered a new chemical entity under the Hatch-Waxman Amendments and would therefore be eligible for five-year market exclusivity under the FDCA. The only other omega-3 based product approved by the FDA is Lovaza. We believe the active moiety in Lovaza and the active moiety in AMR101 are different. Lovaza was approved as a lipid-regulating agent by the FDA in 2004 and has been described in its FDA-approved product label as a combination of ethyl esters of omega-3 fatty acids, principally ethyl-EPA and ethyl-DHA. Our belief that AMR101 should be granted NCE exclusivity is based in part on precedent at FDA for granting NCE status to a previously uncharacterized active moiety, in this case, potentially ethyl-EPA, that was part of a previously approved product. It is currently unclear whether the FDA will view the ethyl-EPA in AMR101 as a previously approved active moiety in Lovaza and deny our request that AMR101 be granted new chemical entity status and the associate period of regulatory exclusivity. We expect the FDA determination on NCE exclusivity will be made in connection with, or soon after, an NDA approval of the MARINE application, and cannot assure you that we will be granted NCE exclusivity.

This marketing exclusivity, if granted, would preclude approval during the exclusivity period of certain 505(b)(2) applications or certain abbreviated new drug applications submitted by another company for another version of the drug. If we are not able to gain or exploit the period of marketing exclusivity, we may face significant competitive threats to our commercialization of these compounds from other manufacturers, including

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the manufacturers of generic alternatives. Further, even if AMR101 is considered to be a new chemical entity and we are able to gain five-year marketing exclusivity, another company could also gain such marketing exclusivity under the provisions of the FDCA, as amended by the Hatch-Waxman Amendments, if such company can, under certain circumstances, complete a human clinical trial process and obtain regulatory approval of its product.

Despite the use of confidentiality agreements and/or proprietary rights agreements, which themselves may be of limited effectiveness, it may be difficult for us to protect our trade secrets.

We rely on trade secrets to protect technology in cases when we believe patent protection is not appropriate or obtainable. However, trade secrets are difficult to protect. While we require certain of our academic collaborators, contractors and consultants to enter into confidentiality agreements, we may not be able to adequately protect our trade secrets or other proprietary information.

Risks Related to our Business

Potential technological changes in our field of business create considerable uncertainty.

We are engaged in the biopharmaceutical field, which is characterized by extensive research efforts and rapid technological progress. New developments in research are expected to continue at a rapid pace in both industry and academia. We cannot assure you that research and discoveries by others will not render some or all of our programs or product candidates uncompetitive or obsolete. Our business strategy is based in part upon new and unproven technologies to the development of biopharmaceutical products for the treatment of cardiovascular diseases. We cannot assure you that unforeseen problems will not develop with these technologies or applications or that any commercially feasible products will ultimately be developed by us.

We are subject to potential product liability.

Prior to 2005, we had commercial revenue and remain subject to the potential risk of product liability claims relating to the manufacturing and marketing of our former products during the period prior to their divestiture. Any person who is injured as a result of using one of our former products during our period of ownership may have a product liability claim against us without having to prove that we were at fault.

In addition, we could be subject to product liability claims by persons who took part in clinical trials involving our current or former development stage products. A successful claim brought against us could have a material adverse effect on our business. We can not guarantee that a product liability claim will not be asserted against us in the future.

We may become subject to liability in connection with the wind-down of our EN101 program.

In 2007, we purchased Ester Neurosciences Limited, an Israeli pharmaceutical company, and its lead product candidate, EN101, an AChE-R mRNA inhibitor for the treatment of myasthenia gravis, or MG, a debilitating neuromuscular disease. In connection with the acquisition, we assumed a license to certain intellectual property assets related to EN101 from the Yissum Research Development Company of The Hebrew University of Jerusalem.

In June 2009, in keeping with our decision to re-focus our efforts on developing improved treatments for cardiovascular disease and cease development of all product candidates outside of our cardiovascular disease focus, we amended the terms of our acquisition agreement with the original shareholders of Ester. Under the terms of this amendment, Amarin was released from all research and development diligence obligations contained in the original agreement and was authorized to seek a partner for EN101. The amendment agreement also provided that any future payment obligations payable by us to the former shareholders of Ester would be

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made only out of income received from potential partners. In connection with this amendment agreement, in August 2009 we issued 1,315,789 ordinary shares to the former Ester shareholders. Under the terms of this amendment agreement, the former Ester shareholders have the option of reacquiring the original share capital of Ester if we are unable to successfully partner EN101.

Following our decision to cease development of EN101, Yissum terminated its license agreement with us. In June 2011, Yissum announced that it had entered into a license agreement with BiolineRX Ltd for the development of EN101 in a different indication, inflammatory bowel disease.

We have received correspondence on behalf of the former shareholders of Ester asserting that we are in breach of its amended agreement due to the fact that the Yissum terminated its license and we failed to return shares of Ester, and assets relating to EN101, to the shareholders, as was required under certain circumstances under the amended agreement. We do not believe these circumstances constitute a breach of the amended agreement, but there can be no assurance as to the outcome of this dispute.

We will incur significant, increased costs as a result of provisions of the Sarbanes-Oxley Act of 2002, and our management will be required to devote substantial time to new compliance initiatives.

The Sarbanes-Oxley Act of 2002 requires, among other things, that we maintain effective internal controls for financial reporting and disclosure. In particular, we perform system and process evaluation and testing of our internal controls over financial reporting and our independent registered public accounting firm reports on the effectiveness of our internal controls over financial reporting, as required by Section 404 of The Sarbanes-Oxley Act of 2002. Based on this evaluation and testing, our management identified a material weakness in internal control over financial reporting as of December 31, 2009 which persisted on December 31, 2010 and which was remediated as of December 31, 2011. Our testing, or the subsequent testing by our independent registered public accounting firm, may reveal deficiencies in our internal controls over financial reporting that are deemed to be new material weaknesses. We expect to incur significant expense and devote substantial management effort toward ensuring compliance with Section 404. We currently do not have an internal audit function, and we will need to hire additional accounting and financial staff with appropriate public company experience and technical accounting knowledge. Moreover, the identification by us or our independent registered public accounting firm of deficiencies in our internal controls that are deemed to be additional material weaknesses could cause the market price of the ADSs to decline, and we could be subject to sanctions or investigations by The NASDAQ Stock Market, the SEC or other regulatory authorities, which would entail expenditure of additional financial and management resources.

We have previously identified a material weakness in our internal control over financial reporting in the past and cannot assure you that material weaknesses will not occur in the future.

As part of the annual financial statement review under International Financial Reporting Standards for the period ended December 31, 2009, management concluded that as of December 31, 2009 there was a deficiency in the company’s internal control over financial reporting relating to the technical expertise and review over the accounting for complex, non-routine transactions that could result in a material misstatement of the consolidated financial statements that would not be prevented or detected on a timely basis. Accordingly, management determined that this control deficiency constituted a material weakness. During 2010, we did not engage in any new non-routine transactions. Nevertheless, based on management’s evaluation of our internal control over financial reporting as of December 31, 2010, management determined that this material weakness in our internal control over financial reporting remained. Specifically, our management concluded there was a deficiency in the company’s internal control over financial reporting relating to the technical expertise and review over the accounting for complex, non-routine transactions that could result in a material misstatement of the consolidated financial statements that would not be prevented or detected on a timely basis.

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In response to this material weakness, our management, with the input, oversight, and support of the Audit Committee, identified and took the following steps to remediate the control deficiency: non-ordinary course transactions are now considered and evaluated by senior finance management; we continue to prepare accounting position papers for all complex transactions; and, where appropriate, management seeks the advice of outside consultants on accounting matters related to the application of U.S. GAAP to complex, non-ordinary course transactions and in other instances as warranted. Any future deficiencies could materially and adversely affect our ability to provide timely and accurate financial information, and the current and future deficiencies may impact investors’ confidence in our internal controls and our company, which could cause our stock price to decline.

A change in our tax residence could have a negative effect on our future profitability.

Under current U.K. legislation, a company incorporated in England and Wales, or which is centrally managed and controlled in the U.K., is regarded as resident in the U.K. for taxation purposes. Under current Irish legislation, a company is regarded as resident for tax purposes in Ireland if it is centrally managed and controlled in Ireland, or, in certain circumstances, if it is incorporated in Ireland. Where a company is treated as tax resident under the domestic laws of both the U.K. and Ireland then the provisions of article 4(3) of the Double Tax Convention between the U.K. and Ireland provides that such enterprise shall be treated as resident only in the jurisdiction in which its place of effective management is situated. We have sought to conduct our affairs in such a way so as to be resident only in Ireland for tax purposes by virtue of having our place of effective management situated in Ireland. Trading income of an Irish company is generally taxable at the Irish corporation tax rate of 12.5%. Non-trading income of an Irish company (e.g., interest income, rental income or other passive income), is taxable at a rate of 25%.

However, we cannot assure you that we are or will continue to be resident only in Ireland for tax purposes. It is possible that in the future, whether as a result of a change in law or the practice of any relevant tax authority or as a result of any change in the conduct of our affairs, we could become, or be regarded as having become resident in a jurisdiction other than Ireland. Should we cease to be an Irish tax resident, we may be subject to a charge to Irish capital gains tax on our assets. Similarly, if the tax residency of any of our subsidiaries were to change from their current jurisdiction for any of the reasons listed above, we may be subject to a charge to local capital gains tax charge on the assets.

The loss of key personnel could have an adverse effect on our business

We are highly dependent upon the efforts of our senior management. The loss of the services of one or more members of senior management could have a material adverse effect on us. As a small company with a streamlined management structure, the departure of any key person could have a significant impact and would be potentially disruptive to our business until such time as a suitable replacement is hired. Furthermore, because of the specialized nature of our business, as our business plan progresses we will be highly dependent upon our ability to attract and retain qualified scientific, technical and key management personnel. There is intense competition for qualified personnel in the areas of our activities. In this environment, we may not be able to attract and retain the personnel necessary for the development of our business, particularly if we do not achieve profitability. The failure to recruit key scientific, technical and management personnel would be detrimental to our ability to implement our business plan.

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Risks Related to Ownership of our ADSs and Common Shares

The price of our ADSs and common shares may be volatile.

The stock market has from time to time experienced significant price and volume fluctuations that may be unrelated to the operating performance of particular companies. In addition, the market prices of the securities of many pharmaceutical and medical technology companies have been especially volatile in the past, and this trend is expected to continue in the future.

As of January 31, 2012 we had 135,929,996 common shares outstanding. As of January 31, 2012 there were 135,612,162 shares held as ADSs and 317,834 held as common shares (which are not held in the form of ADSs). In our October 2009 private placement we issued 66.4 million ADSs and warrants to purchase an additional 33.2 million ADSs. There is a risk that there may not be sufficient liquidity in the market to accommodate significant increases in selling activity or the sale of a large block of our securities. Our ADSs have historically had limited trading volume, which may also result in volatility. If any of our large investors, such as the participants in our October 2009 private placement, seek to sell substantial amounts of our ADSs, particularly if these sales are in a rapid or disorderly manner, or other investors perceive that these sales could occur, the market price of our ADSs could decrease significantly.

The market price of our ADSs and common shares may also be affected by factors such as:

Actual or potential sales of our common shares by our employees, including members of our senior management team, pursuant to pre-arranged stock trading plans could cause our stock price to fall or prevent it from increasing for numerous reasons, and actual or potential sales by such persons could be viewed negatively by other investors.

In accordance with the guidelines specified under Rule 10b5-1 of the Securities and Exchange Act of 1934 and our policies regarding stock transactions, a number of our directors and employees, including members of our senior management team, have adopted and may continue to adopt pre-arranged stock trading plans to sell a portion of our common stock. Generally, sales under such plans by members of our senior management team and directors require public filings. Actual or potential sales of our ADSs by such persons could cause the price of our ADSs to fall or prevent it from increasing for numerous reasons. For example, a substantial amount of our ADSs becoming available (or being perceived to become available) for sale in the public market could cause the market price of our ADSs to fall or prevent it from increasing. Also, actual or potential sales by such persons could be viewed negatively by other investors.

Our existing indebtedness could adversely affect our financial condition.

Our existing indebtedness, which we entered into in January 2012, consists of $150.0 million in aggregate principal amount of 3.50% exchangeable senior notes due 2032, with provisions for the notes to be called on or after January 19, 2017. Our indebtedness and the related annual debt service requirements may adversely impact our business, operations and financial condition in the future. For example, they could:

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The accounting method for convertible debt securities that may be settled in cash, such as our notes, could have a material effect on our reported financial results.

Under the FASB Accounting Standards Codification, or ASC, we may be required to separately account for the liability and equity components of the convertible debt instruments (such as the notes) that may be settled entirely or partially in cash upon conversion in a manner that reflects the issuer’s economic interest cost. The effect of ASC on the accounting for our outstanding convertible notes may be that the equity component is required to be included in the additional paid-in capital section of stockholders’ equity on our consolidated balance sheets and the value of the equity component would be treated as original issue discount for purposes of accounting for the debt component of the notes. As a result, we may be required to record non-cash interest expense as a result of the amortization of the discounted carrying value of the notes to their face amount over the term of the notes. We may be required to report higher interest expense in our financial results because ASC may require interest to include both the current period’s amortization of the debt discount and the instrument’s coupon interest, which could adversely affect our reported or future financial results and the trading price of our ADSs.

Servicing our debt may require a significant amount of cash, and we may not have sufficient cash flow from our business to provide the funds sufficient to pay our substantial debt.

Our ability to make scheduled payments of the principal of, to pay interest on or to refinance our indebtedness, including the notes, depends on our future performance, which is subject to economic, financial, competitive and other factors beyond our control. Our business may not continue to generate cash flow from operations in the future sufficient to service our debt and make necessary capital expenditures. If we are unable to generate such cash flow, we may be required to adopt one or more alternatives, such as selling assets, restructuring debt or obtaining additional equity capital on terms that may be onerous or highly dilutive. Our ability to refinance our indebtedness will depend on the capital markets and our financial condition at such time. We may not be able to engage in any of these activities or engage in these activities on desirable terms, which could result in a default on our debt obligations, including the notes, and have a material adverse effect on the trading price of our ADSs.

We may be able to incur substantial additional debt in the future, subject to the restrictions contained in our future debt instruments, if any, which would intensify the risks discussed above.

We may be a passive foreign investment company, or PFIC, which would result in adverse U.S. tax consequences to U.S. investors.

Amarin Corporation plc and certain of our subsidiaries may be classified as “passive foreign investment companies,” or PFICs, for U.S. federal income tax purposes. The tests for determining PFIC status for a taxable year depend upon the relative values of certain categories of assets and the relative amounts of certain kinds of income. The application of these factors depends upon our financial results, which are beyond our ability to predict or control, and which may be subject to legal and factual uncertainties.

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While we cannot provide any assurance that we are, are not, or will or will not be, a PFIC now or in the future, we believe it prudent to assume that the we were classified as a PFIC in 2011 and that we could be classified as such in 2012 or in future years.

If we are a PFIC, U.S. holders of notes, ordinary shares or ADSs would be subject to adverse U.S. federal income tax consequences, such as ineligibility for any preferred tax rates on capital gains or on actual or deemed dividends, interest charges on certain taxes treated as deferred, and additional reporting requirements under U.S. federal income tax laws and regulations. Whether or not U.S. holders of our ADSs make a timely “QEF election” or “mark-to-market election” may affect the U.S. federal income tax consequences to U.S. holders with respect to the acquisition, ownership and disposition of Amarin ADSs and any distributions such U.S. Holders may receive. A QEF election and other elections that may mitigate the effect of our being classified as a PFIC are unavailable with respect to the notes. Investors should consult their own tax advisors regarding all aspects of the application of the PFIC rules to the notes, ordinary shares and ADSs.

The conditional exchange feature of the notes, if triggered, may adversely affect our financial condition and operating results.

In the event the conditional exchange feature of the notes is triggered, holders of notes will be entitled to exchange the notes at any time during specified periods at their option. If one or more holders elect to exchange their notes, unless we elect to satisfy its exchange obligation by delivering solely the ADSs (other than cash in lieu of any fractional ADS), we would be required to settle a portion or all of its exchange obligation through the payment of cash, which could adversely affect our liquidity. In addition, even if holders do not elect to exchange their notes, we could be required under applicable accounting rules to reclassify all or a portion of the outstanding principal of the notes as a current rather than long-term liability, which would result in a material reduction of our net working capital.

The fundamental change repurchase feature of the notes may delay or prevent an otherwise beneficial takeover attempt of us.

The indenture governing the notes will require us to repurchase the notes for cash upon the occurrence of a fundamental change of Amarin and, in certain circumstances, to increase the exchange rate for a holder that exchanges its notes in connection with a make-whole fundamental change. A takeover of us may trigger the requirement that we purchase the notes and/or increase the exchange rate, which could make it more costly for a potential acquirer to engage in a combinatory transaction with us. Such additional costs may have the effect of delaying or preventing a takeover of us that would otherwise be beneficial to investors.

We do not intend to pay cash dividends on the ordinary shares in the foreseeable future.

We have never paid dividends on ordinary shares and do not anticipate paying any cash dividends on the ordinary shares in the foreseeable future. Under English law, any payment of dividends would be subject to relevant legislation and our Articles of Association, which requires that all dividends must be approved by our Board of Directors and, in some cases, our shareholders, and may only be paid from our distributable profits available for the purpose, determined on an unconsolidated basis.

The rights of our shareholders may differ from the rights typically offered to shareholders of a U.S. corporation.

We are incorporated under English law. The rights of holders of ordinary shares and, therefore, certain of the rights of holders of ADSs, are governed by English law, including the provisions of the Companies Act 2006, and by our Articles of Association. These rights differ in certain respects from the rights of shareholders in typical U.S. corporations. The principal differences include the following:

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U.S. shareholders may not be able to enforce civil liabilities against us.

We are incorporated under the laws of England and Wales, and our subsidiaries are incorporated in various jurisdictions, including foreign jurisdictions. A number of the officers and directors of each of our subsidiaries are non-residents of the United States, and all or a substantial portion of the assets of such persons are located outside the United States. As a result, it may not be possible for investors to effect service of process within the United States upon such persons or to enforce against them judgments obtained in U.S. courts predicated upon the civil liability provisions of the federal securities laws of the United States. We have been advised by our English solicitors that there is doubt as to the enforceability in England in original actions, or in actions for enforcement of judgments of U.S. courts, of civil liabilities to the extent predicated upon the federal securities laws of the United States.

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Our directors, management and affiliated investment funds exercise significant control over our company, which will limit your ability to influence corporate matters.

As of February 15, 2012 our executive officers, directors and affiliated investment funds collectively controlled approximately 15.11% of our outstanding ordinary shares, excluding any shares subject to ADSs that such persons may have the right to acquire upon exercise of outstanding options or warrants. As a result, these shareholders, if they act together, will be able to influence our management and affairs and all matters requiring shareholder approval, including the election of directors and approval of significant corporate transactions.

In addition, we entered into an agreement with various participants in the October 2009 private placement under which investment funds affiliated with Orbimed Advisors LLC, Sofinnova Ventures and Abingworth LLP have the ability to designate persons for Amarin to nominate to its Board of Directors and the other participants have given these investments funds a proxy to vote their securities in favor of these nominees. We have a continuing obligation to nominate one (1) designee of investment funds affiliated with Sofinnova Ventures to its Board of Directors for so long as such funds beneficially own at least fifty percent (50%) of the ADSs they purchased in the October 2009 private placement. Dr. James I. Healy was designated by investment funds affiliated with Sofinnova Ventures pursuant to this arrangement. In addition, we have agreed to nominate one (1) designee of investment funds affiliated with Abingworth LLP to its Board of Directors for so long as such funds beneficially own at least five percent (5%) of our outstanding voting securities. Dr. Joseph Anderson was designated by investment funds affiliated with Abingworth LLP under this arrangement.

This concentration of ownership and the above-described arrangement may have the effect of delaying or preventing a change in control of our company that other shareholders may desire and might negatively affect the market price of the ADSs.

U.S. holders of the ADSs or ordinary shares may be subject to U.S. income taxation at ordinary income tax rates on undistributed earnings and profits.

There is a risk that we will be classified as a controlled foreign corporation, or CFC, for U.S. federal income tax purposes. If we are classified as a CFC, any ADS holder or shareholder that is a U.S. person that owns directly, indirectly or by attribution, 10% or more of the voting power of our outstanding shares may be subject to U.S. income taxation at ordinary income tax rates on all or a portion of our undistributed earnings and profits attributable to “subpart F income.” Such 10% holder may also be taxable at ordinary income tax rates on any gain realized on a sale of ordinary shares or ADS, to the extent of our current and accumulated earnings and profits attributable to such shares. The CFC rules are complex and U.S. Holders of the ordinary shares or ADSs are urged to consult their own tax advisors regarding the possible application of the CFC rules to them in their particular circumstances.