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ABOUT THIS PROSPECTUS SUPPLEMENT

        On April 27, 2015, we filed with the SEC a registration statement on Form S-3 utilizing a shelf registration process relating to the securities described in this prospectus supplement, which became effective upon filing.

        This document is in two parts. The first part is the prospectus supplement, which describes the specific terms of the Notes we are offering and certain other matters relating to us and our financial condition. The second part, the accompanying prospectus, gives more general information about debt securities that we may offer from time to time, some of which may not apply to the Notes we are offering. The rules of the SEC allow us to incorporate by reference information into this prospectus supplement. This information incorporated by reference is considered to be a part of this prospectus supplement, and information that we file later with the SEC, to the extent incorporated by reference, will automatically update and supersede this information. See "Information Incorporated by Reference." You should read this prospectus supplement along with the accompanying prospectus, as well as the documents incorporated by reference. If the description of the offering varies between this prospectus supplement and the accompanying prospectus, you should rely on the information in this prospectus supplement.

        On March 4, 2015, the Company entered into a definitive agreement to acquire Pharmacyclics, Inc. We refer to Pharmacyclics, Inc. and its subsidiaries as "Pharmacyclics." For purposes hereof, "Pharmacyclics acquisition" or the "acquisition of Pharmacyclics" means the acquisition of Pharmacyclics, Inc. pursuant to the merger agreement (as defined below). Except as specifically noted, the descriptions herein of the businesses of AbbVie and Pharmacyclics generally describe the businesses as they exist as of the date of this prospectus supplement and do not assume that the Pharmacyclics acquisition has been consummated.

        We have not authorized any dealer, salesman or other person to give any information or to make any representation other than those contained or incorporated by reference into this prospectus supplement or the accompanying prospectus. You must not rely upon any information or representation not contained or incorporated by reference into this prospectus supplement or the accompanying prospectus. This prospectus supplement and accompanying prospectus do not constitute an offer to sell or the solicitation of an offer to buy any securities other than the shares offered hereby, nor do this prospectus supplement and accompanying prospectus constitute an offer to sell or the solicitation of an offer to buy securities in any jurisdiction to any person to whom it is unlawful to make such offer or solicitation in such jurisdiction. You should not assume that the information contained in this prospectus supplement and accompanying prospectus is accurate on any date subsequent to the date set forth on the front of the document or that any information we have incorporated by reference is correct on any date subsequent to the date of the document incorporated by reference, even though this prospectus supplement and accompanying prospectus is delivered or securities are sold on a later date.

        Except as otherwise provided herein, as used in this prospectus supplement, the terms "Issuer" and "Company" refer to AbbVie Inc., a Delaware corporation, and not to any of its subsidiaries; and "AbbVie," "we," "us" and "our" refer to AbbVie Inc. and its consolidated subsidiaries.

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WHERE TO OBTAIN MORE INFORMATION

        We have filed with the SEC a registration statement on Form S-3 with respect to the securities offered hereby. This prospectus supplement does not contain all the information set forth in the registration statement, parts of which are omitted in accordance with the rules and regulations of the SEC. For further information with respect to us and the securities offered hereby, reference is made to the registration statement.

        We file annual, quarterly and special reports, proxy statements and other information with the SEC. You may read and copy any document we file at the SEC's Public Reference Room in Washington, D.C., located at 100 F Street, N.E. Please call the SEC at 1-800-SEC-0330 for further information on the Public Reference Room. Our SEC filings are also available to the public over the Internet from the SEC's website at www.sec.gov, or our website at www.abbvie.com. Our website and the information contained therein or connected thereto shall not be deemed to be incorporated into this prospectus supplement or registration statement of which this prospectus supplement forms a part and you should not rely on any such information in making your investment decision.

INFORMATION INCORPORATED BY REFERENCE

        The SEC allows us to "incorporate by reference" the information we file with them, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is considered to be part of this prospectus supplement, and information that we file later with the SEC will automatically update and supersede information included or previously incorporated by reference into this prospectus supplement from the date we file the document containing such information. Any statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this prospectus supplement. Except to the extent furnished and not filed with the SEC pursuant to Item 2.02 or Item 7.01 of Form 8-K or as otherwise permitted by the SEC rules, we incorporate by reference the documents listed below and any future filings we will make with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, and such documents shall be deemed to be incorporated by reference into this prospectus supplement and to be a part of this prospectus supplement from the respective dates of filing thereof.

        The documents we incorporate by reference into this prospectus supplement are:

        1.     AbbVie's Annual Report on Form 10-K for the year ended December 31, 2014 (including the information in Part III incorporated by reference from the Company's Definitive Proxy Statement on Schedule 14A, filed on March 20, 2015);

        2.     AbbVie's Current Reports on Form 8-K filed on March 5, 2015, March 6, 2015, March 20, 2015, March 23, 2015 and March 30, 2015.

        3.     The information in our Registration Statement on Form S-4 (File No. 333-202921) filed on March 23, 2015, as amended (the "Form S-4"), under the headings "Risk Factors" and "Unaudited Pro Forma Condensed Combined Financial Statements."

        4.     The information in Pharmacyclics' Annual Report on Form 10-K, filed on February 18, 2015, under Item 7 (Management's Discussion and Analysis of Financial Condition and Results of Operations) and Item 8 (Financial Statements and Supplementary Data) and Item 9A (Controls and Procedures).

        5.     The information in Pharmacyclics' Quarterly Report on Form 10-Q, filed on May 4, 2015, under Item 1 (Financial Information) and Item 2 (Management's Discussion and Analysis of Financial Condition and Results of Operations).

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        Documents incorporated by reference are available from us, without charge, excluding all exhibits unless specifically incorporated by reference in the documents. You may obtain documents incorporated by reference into this prospectus supplement by writing to us at the following address or by calling us at the telephone number listed below:

AbbVie Inc.
1 North Waukegan Road
North Chicago, Illinois 60064
Attention: Investor Relations
(847) 932-7900
http://www.abbvieinvestor.com/

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INDUSTRY AND MARKET DATA

        This prospectus supplement and the accompanying prospectus, and any document incorporated by reference into this prospectus supplement and the accompanying prospectus, may include industry and trade association data, forecasts and information that we have prepared based, in part, upon data, forecasts and information obtained from independent trade associations, industry publications and surveys and other information available to us. Some data are also based on our good-faith estimates, which are derived from management's knowledge of the industry and independent sources. Industry publications and surveys and forecasts generally state that the information contained in these materials has been obtained from sources believed to be reliable. Although we believe these sources are reliable, we have not independently verified the information. In certain of the markets in which we operate, it may be difficult to directly ascertain industry or market data. Unless otherwise noted, statements as to our market share and market position are approximated and based on management experience and estimates using the above-mentioned third-party data combined with our internal analysis and estimates. While we are not aware of any misstatements regarding our industry data presented in the applicable documents, our estimates involve risks and uncertainties and are subject to change based on various factors, including those discussed under the heading "Risk Factors" in this prospectus supplement and the accompanying prospectus, as well as the documents incorporated by reference into this prospectus supplement and the accompanying prospectus. Similarly, while we believe our internal research is reliable, such research has not been verified by any independent sources.

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FORWARD-LOOKING STATEMENTS

        This prospectus supplement contains, and the accompanying prospectus and any free writing prospectus and documents incorporated by reference into this prospectus supplement or the accompanying prospectus may contain certain forward-looking statements regarding business strategies, market potential, future financial performance and other matters. The words "believe," "expect," "anticipate," "project" and similar expressions, among others, generally identify "forward-looking statements," which speak only as of the date the statements were made. The matters discussed in these forward-looking statements are subject to risks, uncertainties and other factors that could cause actual results to differ materially from those projected, anticipated or implied in the forward-looking statements. Where, in any forward-looking statement, an expectation or belief as to future results or events is expressed, such expectation or belief is based on the current plans and expectations of AbbVie management and expressed in good faith and believed to have a reasonable basis, but there can be no assurance that the expectation or belief will result or be achieved or accomplished. Factors that could cause actual results or events to differ materially from those anticipated include the ability to consummate the Pharmacyclics acquisition, the ability to realize the anticipated benefits of the acquisition, on the expected timeframe or at all, the matters described in our Annual Report on Form 10-K for the year ended December 31, 2014 under "Risk Factors" and "Management's Discussion and Analysis of Financial Condition and Results of Operations" and the matters described in the Form S-4 under "Risk Factors." AbbVie does not undertake any obligation to update the forward-looking statement as a result of new information, future events or otherwise, except as otherwise required by law. Please carefully review and consider the various disclosures made in this prospectus supplement and the accompanying prospectus and any free writing prospectus and documents incorporated by reference into this prospectus supplement or the accompanying prospectus that attempt to advise interested parties of the risks and factors that may affect our business, prospects and results of operations.

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DESCRIPTION OF THE PHARMACYLICS ACQUISITION

        The following description of the merger agreement does not purport to be complete and is qualified in its entirety by reference to the full text of the merger agreement, which is attached as Exhibit 2.1 to our Current Report on Form 8-K filed with the SEC on March 6, 2015, and the amendment to the merger agreement, which is attached as Exhibit 2.1 to our Current Report on Form 8-K filed with the SEC on March 23, 2015.

Merger Agreement

        On March 4, 2015, AbbVie, Oxford Amherst Corporation, Oxford Amherst LLC and Pharmacyclics entered into the merger agreement (as amended on March 22, 2015), pursuant to which, among other things, Oxford Amherst Corporation has commenced a tender offer (the "Offer") to purchase all of the issued and outstanding shares of Pharmacyclics common stock, par value $0.0001 per share (the "Pharmacyclics Shares"), in exchange for cash and/or stock consideration with a value of $261.25 per Pharmacyclics Share. Immediately following the closing of the Offer, on the terms and subject to the conditions set forth in the merger agreement, (i) Oxford Amherst Corporation will be merged with and into Pharmacyclics (the "First Merger"), with Pharmacyclics surviving the First Merger and (ii) immediately following the First Merger, Pharmacyclics will be merged with and into Oxford Amherst LLC (the "Second Merger" and, together with the First Merger, the "Merger"), with Oxford Amherst LLC surviving the Second Merger, such that following the Second Merger, the surviving company in the Second Merger will be a wholly owned direct subsidiary of AbbVie.

        In the Offer and the Merger, holders of Pharmacyclics Shares will have the option to elect among three forms of consideration for each Pharmacyclics Share:

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$152.25 in cash and a number of shares of AbbVie common stock equal to $109.00 divided by the volume weighted average sale price per share of AbbVie common stock as reported on the New York Stock Exchange (the "NYSE") for the ten consecutive trading days ending on and including the second trading day prior to the final expiration date of the Offer, as calculated by Bloomberg Financial LP under the function "ABBV UN Equity AQR" (the "Mixed Consideration");



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$261.25 in cash (the "Cash Consideration"); or



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a number of shares of AbbVie common stock equal to $261.25 divided by the volume weighted average sale price per share of AbbVie common stock as reported on the NYSE for the ten consecutive trading days ending on and including the second trading day prior to the final expiration date of the Offer, as calculated by Bloomberg Financial LP under the function "ABBV UN Equity AQR" (the "Stock Consideration").

Holders of Pharmacyclics Shares who do not make a valid election in either the Offer or the Merger will receive the Mixed Consideration for their Pharmacyclics Shares if the Offer and the Merger are consummated. Holders who elect to receive the Cash Consideration or Stock Consideration will be subject to proration to ensure that approximately 41.7% of the aggregate consideration in each of the Offer and the Merger will be paid in AbbVie common stock and approximately 58.3% of the aggregate consideration in each of the Offer and the Merger (in the case of the Offer, as reduced by the Pharmacyclics Shares held by stockholders who have properly exercised and perfected dissenters' rights under the General Corporation Law of the State of Delaware) will be paid in cash.

        The Offer is subject to certain conditions, including:

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that a majority of the outstanding Pharmacyclics Shares have been validly tendered in the Offer (and not properly withdrawn);



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receipt of required regulatory approvals;

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lack of legal prohibitions;



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the listing of the shares of AbbVie common stock to be issued in the Offer and the Merger on the NYSE;



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the receipt of opinions by each of AbbVie and Pharmacyclics from their respective legal counsel regarding the tax treatment of the Offer and the Merger;



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the effectiveness of the registration statement on Form S-4 filed in connection with the Offer and the Merger;



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no material adverse effect (as defined in the merger agreement) having occurred with respect to Pharmacyclics and its subsidiaries;



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the truth and accuracy of Pharmacyclics' representations and warranties made in the merger agreement; and



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Pharmacyclics and its subsidiaries being in material compliance with their covenants under the merger agreement.

        The merger agreement contains certain termination rights by AbbVie and Pharmacyclics. If the merger agreement is terminated under specified circumstances, including with respect to the change of the recommendation of Pharmacyclics' board of directors, Pharmacyclics will pay AbbVie a termination fee equal to $680,000,000.

        In connection with the announcement of the execution of the merger agreement, AbbVie announced that it intended to execute an accelerated share repurchase program to repurchase at least half of the equity issued for the transaction, and that its share repurchase authorization increased from $5 billion to $10 billion.

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RISK FACTORS

        You should carefully consider the following risk factors, as well as the other information included or incorporated by reference into this prospectus supplement and the accompanying prospectus, before making an investment decision. These risks are not the only risks that we face in our business, in respect of the Pharmacyclics acquisition and/or in connection with this offering. Our business, financial condition and results of operations, the success of the Pharmacyclics acquisition and/or the Notes offered hereby could also be affected by additional factors that are not presently known to us or that we currently do not consider to be material.

Risks Relating to Our Business

        For a discussion of the risks related to our business you should carefully consider the risks, uncertainties and assumptions discussed under "Part I—Item 1A. Risk Factors" in the Issuer's Annual Report on Form 10-K for the fiscal year ended December 31, 2014, as amended, the risks described under "Risk Factors" beginning on page 13 of the Form S-4, and in other documents that we subsequently file with the SEC that update, supplement or supersede such information, all of which are incorporated by reference into this prospectus supplement. See "Where You Can Find More Information."

Risks Related to this Offering

         In addition to indebtedness that will be issued in this offering, the Issuer has significant outstanding unused borrowing capacity and may incur additional debt in the future. The terms of this indebtedness could restrict the activities of AbbVie.

        In October 2014, the Issuer entered into the Revolving Credit Facility (as defined below) with various financial institutions. In March 2015, the Issuer entered into the Bridge Loan Facility (as defined below) with various financial institutions. There are currently no amounts outstanding under these credit facilities. These credit facilities impose restrictions on the Issuer and its subsidiaries, including certain restrictions on their ability to incur liens on their assets. In addition, these credit facilities require the Issuer to maintain compliance with a financial covenant. The Issuer's ability to comply with these restrictions and covenants may be affected by events beyond its control. If the Issuer breaches any of these restrictions or covenants and does not obtain a waiver from the lenders, then, subject to applicable cure periods, any outstanding indebtedness under either credit facility could be declared immediately due and payable. AbbVie may incur significantly more debt in the future.

         The Issuer has limited direct operations and depends on dividends and other distributions from its subsidiaries.

        The Issuer has limited direct operations. The Issuer's principal assets are the equity interests that the Issuer holds in its subsidiaries. As a result, the Issuer depends on dividends and other distributions from its subsidiaries to generate the funds necessary to meet its financial obligations, including the payment of principal and interest on its outstanding indebtedness. The Issuer's subsidiaries are legally distinct from the Issuer and have no obligation to pay amounts due on the Issuer's indebtedness or to make funds available for such payment. In addition, the Issuer's subsidiaries will be permitted under the terms of the indenture governing the Notes to incur additional indebtedness that may restrict or prohibit the making of distributions, the payment of dividends or the making of loans by such subsidiaries to the Issuer. The Issuer cannot assure you that the agreements governing the current and future indebtedness of its subsidiaries will permit such subsidiaries to provide it with sufficient dividends, distributions or loans to fund payments on the Notes when due.

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         An increase in interest rates could result in a decrease in the market values of the Notes.

        In general, as market interest rates rise, notes bearing interest at a fixed rate decline in value because the premium over market interest rates, if any, will decline. Consequently, if you purchase the Notes and market interest rates increase, the market values of your Notes may decline. The Issuer cannot predict the future level of market interest rates.

         Changes in the Issuer's credit ratings may adversely affect the values of the Notes.

        Any ratings assigned to the Notes could be lowered, suspended or withdrawn entirely by the rating agencies if, in each rating agency's judgment, circumstances warrant. Actual or anticipated changes or downgrades in the Issuer's credit ratings, including any announcement that the Issuer's ratings are under further review for a downgrade, could affect the market values of the Notes.

         The indenture governing the Notes will not restrict the amount of additional debt that AbbVie may incur.

        The Notes and the indenture under which the Notes will be issued do not place any limitation on the amount of debt that AbbVie may incur (other than certain limited restrictions on the incurrence of certain secured debt). AbbVie's incurrence of additional debt may have important consequences for you as a holder of the Notes, including making it more difficult for the Issuer to satisfy its obligations with respect to the Notes, a loss in the market values of the Notes and a risk that any credit rating of the Notes is lowered or withdrawn. In addition, the Issuer is not restricted under the indenture governing the Notes from paying dividends or issuing or repurchasing its securities.

        There are no financial covenants in the indenture governing the Notes. Except for the covenants described under "Description of Notes—Certain Covenants of AbbVie" and "Description of Notes—Consolidation, Merger and Sale of Assets," there are no covenants or any other provisions in the indenture which may afford you protection in the event of a highly leveraged transaction, including one that may or may not result in a change of control of the Issuer.

         There are currently no markets for the Notes, and active trading markets may not develop for the Notes.

        The Notes are new securities for which there are no established public markets. The Issuer does not intend to have the Notes listed on a national securities exchange or to arrange for quotation on any automated dealer quotation systems. The underwriters have advised the Issuer that they intend to make a market for each series of the Notes as permitted by applicable laws and regulations. However, the underwriters are not obligated to make a market for any series of the Notes, and they may discontinue their market-making activities at any time without notice. In addition, the liquidity of the trading markets in the Notes and the market prices quoted for the Notes may be adversely affected by changes in the overall market for securities and by changes in AbbVie's financial performance or prospects or changes in the financial performance or prospects of companies in AbbVie's industry. Active trading markets for the Notes may not develop or be sustained and there can be no assurance as to the liquidity of any markets that do develop. You may not be able to sell your Notes at a particular time, and the price that you receive when you sell may not be favorable.

         Neither the Issuer nor any of its subsidiaries has any property that has been determined to be a principal domestic property under the indenture governing the Notes.

        The indenture governing the Notes includes covenants that, among other things, limit the Issuer's ability and the ability of the Issuer's subsidiaries to create or permit to exist mortgages on and other liens and enter into sale and leaseback transactions with respect to principal domestic properties. However, as of the date of this prospectus supplement, neither the Issuer, nor any of its subsidiaries has, nor does the Issuer expect that following the consummation of the Pharmacyclics acquisition,

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either it or any of its subsidiaries will have any property that constitutes a principal domestic property under the indenture governing the Notes.

         The Issuer's board of directors has broad discretion to determine that a property is not a principal domestic property and therefore not subject to certain covenants in the indenture governing the Notes.

        The indenture governing the Notes includes covenants that, among other things, limit the Issuer's ability and the ability of the Issuer's subsidiaries to create or permit to exist mortgages on and other liens and enter into sale and leaseback transactions with respect to principal domestic properties. The indenture governing the Notes provides that a principal domestic property means any building, structure or other facility, together with the land on which it is erected and fixtures comprising a part of it, used primarily for manufacturing, processing, research, warehousing or distribution and located in the United States, excluding its territories, possessions and Puerto Rico, owned or leased by the Issuer or any of its domestic subsidiaries and having a net book value which, on the date the determination as to whether a property is a principal domestic property is being made, is in excess of 2% of the consolidated net assets of the Issuer, other than any such building, structure or other facility or a portion thereof which is an air or water pollution control facility financed by State or local governmental obligations, or which the chairman of the board, chief executive officer, an executive vice president, a senior vice president or a vice president and the chief financial officer, treasurer, or assistant treasurer of the Issuer determine in good faith, at any time on or prior to such date, is not of material importance to the total business conducted or assets owned by the Issuer and its subsidiaries as an entirety. Although it has not yet done so, under the terms of the indenture governing the Notes, the Issuer's chairman of the board or any of the Issuer's executive officers listed above may determine from time to time that an AbbVie property is not a principal domestic property and therefore such property is not subject to the covenants in the indenture governing the Notes.

         The Notes will not be guaranteed by any of the Issuer's subsidiaries and are structurally subordinated to any existing or future preferred stock, indebtedness, guarantees and other liabilities of the Issuer's subsidiaries.

        The Notes will be obligations exclusively of the Issuer and will not be guaranteed by any of the Issuer's subsidiaries. As a result, the Notes will be structurally subordinated to existing or future preferred stock, indebtedness, guarantees and other liabilities, including trade payables, of the Issuer's subsidiaries. The indenture governing the Notes does not restrict the Issuer or its subsidiaries from incurring substantial additional indebtedness in the future.

        As of December 31, 2014, on a pro forma basis, giving effect to the issuance and sale of the Notes and the application of the estimated net proceeds therefrom, as described in this prospectus supplement, as if such transaction had occurred on December 31, 2014, the Issuer would have had approximately $32 billion of outstanding indebtedness. In addition, the Issuer has entered into the Bridge Loan Facility and the Revolving Credit Facility, which have a borrowing capacity of up to $18 billion (subject to reductions in the circumstances described under "Description of Other Indebtedness") and $3 billion respectively. The Issuer's subsidiaries are separate and distinct legal entities from the Issuer and such subsidiaries have no obligation to pay any amounts due on the Notes or to provide the Issuer with funds to meet the payment obligations on the Notes. Any payment of dividends, loans or advances by the Issuer's subsidiaries could be subject to statutory or contractual restrictions and will be contingent upon the subsidiaries' earnings and business considerations. The Issuer's right to receive any assets of any of its subsidiaries upon their bankruptcy, liquidation, or similar reorganization, and the rights of the holders of the Notes, will be structurally subordinated to all existing and future indebtedness and other liabilities of such subsidiaries.

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         The Notes are subject to prior claims of secured creditors.

        The Notes will be unsecured, ranking equally in right of payment with other unsecured, unsubordinated indebtedness of the Issuer and effectively subordinated in right of payment to any secured debt of the Issuer to the extent of the value of the assets securing such indebtedness. As of December 31, 2014, the Issuer did not have any significant secured debt outstanding. However, the indenture governing the Notes, and the credit agreements governing the Bridge Loan Facility and the Revolving Credit Facility permit the Issuer and its subsidiaries to incur secured debt under certain circumstances, and the amounts could be substantial. If the Issuer incurs any debt secured by its assets or the assets of its subsidiaries, these assets could be subject to the claims of secured creditors that are prior to your claim as a holder of Notes.

        In the event of a bankruptcy, liquidation, or similar proceeding, the pledged assets of the Issuer would be available to satisfy obligations of the secured debt before any payment could be made on the Notes. As a result, the Notes will be effectively subordinated to any secured debt that the Issuer may have. To the extent that such pledged assets cannot satisfy such secured debt, the holders of such debt would have a claim for any shortfall that would rank equally in right of payment with the Notes.

         The Issuer's credit ratings may not reflect all risks of your investment in the Notes.

        Any credit ratings assigned or that will be assigned to the Notes are limited in scope, and do not address all material risks relating to an investment in the Notes, but rather reflect only the view of each rating agency at the time the rating is issued. An explanation of the significance of such rating may be obtained from such rating agency. There can be no assurance that such credit ratings will remain in effect for any given period of time or that a rating will not be lowered, suspended or withdrawn entirely by the applicable rating agencies, if, in such rating agency's judgment, circumstances so warrant.

        Agency credit ratings are not a recommendation to buy, sell or hold any security. Each agency's rating should be evaluated independently of any other agency's rating. Actual or anticipated changes or downgrades in the Issuer's credit ratings, including any announcement that its ratings are under further review for a downgrade, could affect the market values of the Notes and increase the Issuer's corporate borrowing costs.

         The Issuer may be required to redeem all of the Notes on the special mandatory redemption date at a redemption price equal to 101% of the aggregate principal amount of the Notes, and, as a result, holders of the Notes may not obtain their expected return on the Notes.

        The Issuer may not consummate the Pharmacyclics acquisition within the timeframe specified under "Description the Notes—Special Mandatory Redemption." The Issuer's ability to consummate the Pharmacyclics acquisition is subject to various closing conditions, including regulatory approvals, and other matters over which the Issuer may have limited or no control. If (x) the Issuer fails to consummate the Pharmacyclics acquisition on or before February 3, 2016 or (y) the Issuer notifies the Trustee in respect of the Notes that the merger agreement has been terminated in accordance with its terms prior to the consummation of the Pharmacyclics acquisition, the Issuer will be required to redeem all of the Notes at a redemption price equal to 101% of their principal amount plus accrued and unpaid interest, if any, to, but excluding the special mandatory redemption date.

        If the Issuer redeems the Notes pursuant to the Special Mandatory Redemption provisions of the Notes, you may not obtain your expected return on the Notes and may not be able to reinvest the proceeds from such special mandatory redemption in an investment that results in a comparable return. In addition, as a result of the Special Mandatory Redemption provisions of the Notes, the trading prices of the Notes may not reflect the financial results of AbbVie's business or macroeconomic factors. You will have no rights under the special mandatory redemption provisions of the Notes if the Pharmacyclics acquisition closes, nor will you have any right to require the Issuer to repurchase your

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Notes if, between the closing of this offering and the completion of the Pharmacyclics acquisition, the Issuer experiences any changes (including any material adverse changes) in its business or financial condition. See "Description of Notes—Special Mandatory Redemption."

         The Issuer may choose to redeem the Notes of any series prior to maturity.

        The Issuer may redeem some or all of the Notes of any series at any time. See "Description of Notes—Optional Redemption." Although the Notes contain provisions designed to compensate you for the lost value of your Notes if the Issuer redeems some or all of the Notes prior to maturity, they are only an approximation of this lost value and may not adequately compensate you. Furthermore, depending on prevailing interest rates at the time of any such redemption, you may not be able to reinvest the redemption proceeds in a comparable security at an interest rate as high as the interest rate of the Notes being redeemed or at an interest rate that would otherwise compensate you for any lost value as a result of any redemption of Notes.

Risk Factors Relating to AbbVie and the Combined Company

         AbbVie may fail to realize all of the anticipated benefits of the transactions or those benefits may take longer to realize than expected.

        The full benefits of the transactions, including the anticipated sales or growth opportunities, may not be realized as expected or may not be achieved within the anticipated time frame, or at all. Failure to achieve the anticipated benefits of the transactions could adversely affect AbbVie's results of operations or cash flows, cause dilution to the earnings per share of the Issuer, decrease or delay the expected accretive effect of the transactions, and negatively impact the price of the Issuer's common stock.

        In addition, AbbVie and Pharmacyclics will be required to devote significant attention and resources prior to closing to prepare for the post-closing operation of the combined company, and AbbVie will be required to devote significant attention and resources post-closing to successfully align the business practices and operations of AbbVie and Pharmacyclics. This process may disrupt the businesses and, if ineffective, would limit the anticipated benefits of the Pharmacyclics acquisition.

         AbbVie's ability to realize the anticipated benefits of the Pharmacyclics acquisition will depend on its ability to effectively and profitably commercialize IMBRUVICA® (ibrutinib).

        The anticipated benefits of the Pharmacyclics acquisition will depend on AbbVie's ability to effectively and profitably commercialize IMBRUVICA® (ibrutinib), including AbbVie's ability to:

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create continued market demand through education, marketing and sales activities;



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achieve market acceptance and generate product sales;



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receive continued reimbursement from third-party payers, such as federal government payers and private insurance programs;



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comply with post-marketing requirements established by the U.S. Food and Drug Administration, or FDA, and applicable foreign regulatory agencies, including any requirements established by the FDA or foreign regulatory agencies in the future;



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comply with the regulations and guidelines of the FDA, and applicable foreign regulatory agencies, surrounding promotional activities;



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conduct the post-marketing studies required by the FDA;



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ensure that the active pharmaceutical ingredient for IMBRUVICA® (ibrutinib) and the finished product are manufactured in sufficient quantities and in compliance with requirements of the FDA and similar foreign regulatory agencies and with an acceptable quality and pricing level in order to meet commercial demand; and



•

ensure that the entire supply chain efficiently and consistently delivers IMBRUVICA® (ibrutinib) to AbbVie's customers.

        The commercialization of IMBRUVICA® (ibrutinib) may not be successful for a number of reasons, including:

•

unexpected challenges from competitors with potential new therapeutic options and also in overcoming inertia in the adoption of upcoming novel therapies such as IMBRUVICA® (ibrutinib);



•

new safety issues or concerns being reported that may impact or narrow the approved indications;



•

Pharmacyclics' level of experience in marketing IMBRUVICA® (ibrutinib) is limited to the time during which it has been commercially available for any patient population;



•

reimbursement and coverage policies of government and private payers such as Medicare, Medicaid, insurance companies, health maintenance organizations and other plan administrators could change unexpectedly;



•

government price controls and reimbursement policies in foreign countries;



•

the relative price of IMBRUVICA® (ibrutinib) as compared to alternative treatment options;



•

changed or increased legal or regulatory restrictions and our ability to comply with such restrictions;



•

changes to the label for IMBRUVICA® (ibrutinib) that further restrict its marketing, arising from the results of any other on-going or future studies, including post-marketing studies; and



•

ability to obtain adequate commercial supplies of IMBRUVICA® (ibrutinib) to meet demand or at an acceptable cost because of manufacturing or other issues, including a potential recall of IMBRUVICA® (ibrutinib).

        If the commercialization of IMBRUVICA® (ibrutinib) is unsuccessful, AbbVie's ability to generate revenue from product sales and realize the anticipated benefits of the Pharmacyclics acquisition will be adversely affected.

         AbbVie and Pharmacyclics will incur direct and indirect costs as a result of the Pharmacyclics acquisition.

        AbbVie and Pharmacyclics will incur substantial expenses in connection with and as a result of completing the Pharmacyclics acquisition and, following the completion of the Pharmacyclics acquisition, AbbVie expects to incur additional expenses in connection with combining the businesses, operations, policies and procedures of AbbVie and Pharmacyclics. Factors beyond AbbVie's control could affect the total amount or timing of these expenses, many of which, by their nature, are difficult to estimate accurately.

         AbbVie's and Pharmacyclics' actual financial positions and results of operations may differ materially from the unaudited pro forma financial data included in this document.

        The pro forma financial information contained in this document is presented for illustrative purposes only and may differ materially from what AbbVie's actual financial position or results of

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operations would have been had the transactions been completed on the dates indicated. The pro forma financial information has been derived from the audited and unaudited historical financial statements of AbbVie and certain adjustments and assumptions have been made regarding the combined company after giving effect to the transactions. The assets and liabilities of Pharmacyclics have been measured at fair value based on various preliminary estimates using assumptions that AbbVie management believes are reasonable utilizing information currently available. The process for estimating the fair value of acquired assets and assumed liabilities requires the use of judgment in determining the appropriate assumptions and estimates. These estimates may be revised as additional information becomes available and as additional analyses are performed. Differences between preliminary estimates in the pro forma financial information and the final acquisition accounting will occur and could have a material impact on the pro forma financial information and the combined company's financial position and future results of operations.

        In addition, the assumptions used in preparing the pro forma financial information may not prove to be accurate, and other factors may affect AbbVie's financial condition or results of operations following the closing. Any potential decline in AbbVie's financial condition or results of operations may cause significant variations in the share price of AbbVie.

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USE OF PROCEEDS

        We expect the net proceeds to us from this offering will be approximately $16,560 million (after deducting underwriting discounts and our estimated offering expenses). We intend to use the net proceeds from the sale of the Notes to fund the cash component of the acquisition consideration in connection with the Pharmacyclics acquisition, to finance the Share Repurchase and to pay related fees and expenses, and the remainder, if any, for general corporate purposes.

        The following table summarizes the estimated sources and uses of the funds as if the proposed transactions had been completed on December 31, 2014. Actual amounts set forth in the table and in the accompanying footnotes are subject to adjustments and may differ at the time of the consummation of the proposed transactions depending on several factors, including changes in the actual amount of fees and expenses related to the proposed transactions, the actual closing date of the Pharmacyclics acquisition and the outstanding amount of indebtedness at that time. There can be no assurance whether the Pharmacyclics acquisition will be consummated under the terms contemplated or at all and, if consummated, when the closing will take place.

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CONSOLIDATED RATIO OF EARNINGS TO FIXED CHARGES

        The table below sets forth AbbVie's historical ratio of earnings to fixed charges for the periods indicated. We have not presented a ratio of earnings to fixed charges and preferred stock dividends because we did not have preferred stock outstanding as of the date of this prospectus supplement. The following table should be read in conjunction with our consolidated financial statements and accompanying notes and Management's Discussion and Analysis of Financial Condition and Results of Operations included in our Annual Report on Form 10-K for the fiscal year ended December 31, 2014, which are incorporated by reference into this prospectus supplement. For further information, see Exhibit 12.1 (Computation of Ratio of Earnings to Fixed Charges) to the registration statement of which this prospectus supplement forms a part.

        The table below sets forth our pro forma combined ratio of consolidated earnings to fixed charges for the year ended December 31, 2014. In the case of the row entitled "Pro forma combined ratio of consolidated earnings to fixed charges," see "Unaudited Pro Forma Condensed Combined Financial Data" for a description of the pro forma adjustments. See also "Use of Proceeds."

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CAPITALIZATION

        The following table sets forth our capitalization as of December 31, 2014:

•

on an actual basis and



•

on a pro forma basis as further adjusted for the proposed transactions in connection with the consummation of the Pharmacyclics acquisition.

        Actual amounts set forth in the table and in the accompanying footnotes are subject to adjustments and may differ at the time of the consummation of the proposed transactions depending on several factors, including changes in the actual amount of fees and expenses related to the proposed transactions, the actual closing date of the Pharmacyclics acquisition and the outstanding amount of indebtedness at that time. There can be no assurance whether the Pharmacyclics acquisition will be consummated under the terms contemplated or at all and, if consummated, when the closing will take place.

        You should read this table in conjunction with "Use of Proceeds," "Unaudited Pro Forma Condensed Combined Financial Data" and the financial statements and related notes thereto in our Annual Report on Form 10-K for the year ended December 31, 2014, which are incorporated by reference into this prospectus supplement.

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UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL STATEMENTS

        The following unaudited pro forma condensed combined financial statements have been prepared to illustrate the estimated effects of (i) the issuance of $16.7 billion aggregate principal amount of the Notes pursuant to this offering, and (ii) the acquisition of Pharmacyclics by AbbVie. The unaudited pro forma condensed combined balance sheet as of December 31, 2014 assumes the Pharmacyclics acquisition and the issuance of the Notes occurred on December 31, 2014. The unaudited pro forma condensed combined statement of earnings for the year ended December 31, 2014 assumes the Pharmacyclics acquisition and the issuance of the Notes occurred on January 1, 2014. The historical consolidated financial information has been adjusted to reflect factually supportable items that are directly attributable to the acquisition and, with respect to the statement of income only, expected to have a continuing impact on the combined results.

        The pro forma financial statements have been prepared using the acquisition method of accounting for business combinations under accounting principles generally accepted in the United States, with AbbVie treated as the acquirer. The acquisition method of accounting is dependent upon certain valuations and other studies that have yet to commence or progress to a stage where there is sufficient information for a definitive measure. Accordingly, the pro forma adjustments are preliminary, have been made solely for the purpose of providing pro forma financial statements, and are subject to revision based on a final determination of fair value as of the date of acquisition. Differences between these preliminary estimates and the final acquisition accounting may have a material impact on the accompanying pro forma financial statements and AbbVie's future results of operations and financial position.

        The pro forma financial statements do not give effect to the costs of any integration activities or benefits that may result from the realization of future cost savings from operating efficiencies, or any other synergies that may result from the Pharmacyclics acquisition.

        The pro forma financial statements are provided for informational purposes only and do not purport to represent what the actual consolidated results of operations or the consolidated financial position of AbbVie would have been had the combination occurred on the dates assumed, nor are they necessarily indicative of future consolidated results of operations or consolidated financial position. The pro forma financial statements should be read in conjunction with the accompanying notes to the pro forma financial statements and the audited consolidated financial statements and accompanying notes of AbbVie and Pharmacyclics incorporated by reference herein.

        Actual amounts set forth in the table and in the accompanying footnotes are subject to adjustments and may differ at the time of the consummation of the proposed transactions depending on several factors, including changes in the actual amount of fees and expenses related to the proposed transactions, the actual closing date of the Pharmacyclics acquisition and the outstanding amount of indebtedness at that time. There can be no assurance whether the Pharmacyclics acquisition will be consummated under the terms contemplated or at all and, if consummated, when the closing will take place.

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AbbVie Unaudited Pro Forma Condensed Combined Balance Sheet

As of December 31, 2014