As filed with the Securities and Exchange Commission on January 10, 2008

Registration No. 333-

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549

FORM S-8
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933

THE MEDICINES COMPANY
(Exact name of Registrant as specified in its charter)

Delaware
(State or other jurisdiction of
incorporation or organization)

04-3324394
(I.R.S. Employer
Identification No.)

8 Campus Drive
Parsippany, New Jersey 07054
(Address of Principal Executive Offices including Zip Code)

2007 EQUITY INDUCEMENT PLAN
(Full title of the Plan)

Clive A. Meanwell
Chairman and Chief Executive Officer
The Medicines Company
8 Campus Drive
Parsippany, New Jersey 07054
(973) 656-1616

(Name and address, including zip code, and telephone
number, including area code, of agent for service)

CALCULATION OF REGISTRATION FEE


Title of Securities to be Registered	Amount of Shares to be Registered (1)	Proposed Maximum Offering Price Per Share (2)		Proposed Maximum Aggregate Offering Price (2)		Amount of Registration Fee

Common Stock, $0.001 par value per share	1,700,000	$	19.30	$	32,810,000	$	1,289.43

(1) In accordance with Rule 416 under the Securities Act of 1933, as amended, or the Securities Act, this registration statement shall be deemed to cover any additional shares of common stock that may from time to time be offered or issued to prevent dilution resulting from any stock dividend, stock split, or similar transactions.

(2) Estimated solely for the purpose of calculating the registration fee pursuant to Rule 457(c) and Rule 457(h) of the Securities Act for the 1,700,000 shares registered hereunder (based on the average of the high ($19.66) and low ($18.94) prices for our common stock reported by the Nasdaq Global Select Market on January 8, 2008).

PART I

INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS

Item 1. Plan Information .

The information required by Item 1 is included in documents sent or given to participants in The Medicines Company’s 2007 Equity Inducement Plan, or the 2007 Plan, pursuant to Rule 428(b)(1) of the Securities Act.

Item 2 . Registrant Information and Employee Plan Annual Information.

The written statement required by Item 2 is included in documents sent or given to participants in the 2007 Plan, pursuant to Rule 428(b)(1) of the Securities Act.

PART II

INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3. Incorporation of Documents by Reference .

We are subject to the informational and reporting requirements of Sections 13(a), 14 and 15(d) of the Securities Exchange Act of 1934, or the Exchange Act. In accordance with the Exchange Act, we file reports, proxy statements and other information with the Securities and Exchange Commission, which we refer to as the Commission. The following documents, which we previously filed with the Commission, are incorporated by reference in this registration statement:

(a) our annual report on Form 10-K for the year ended December 31, 2006;

(b) our proxy statement for our 2007 annual meeting of stockholders filed with the Commission on April 18, 2007;

(d) our quarterly report on Form 10-Q for the three months ended June 30, 2007;

(e) our quarterly report on Form 10-Q for the three months ended September 30, 2007;

(f) our current report on Form 8-K filed with the Commission on January 16, 2007;

(g) our current report on Form 8-K filed with the Commission on February 14, 2007;

(h) our current report on Form 8-K filed with the Commission on February 16, 2007;

(i) our current report on Form 8-K filed with the Commission on April 11, 2007;

(j) our current report on Form 8-K filed with the Commission on April 18, 2007;

(k) our current report on Form 8-K filed with the Commission on April 27, 2007;

(l) our current report on Form 8-K filed with the Commission on July 2, 2007;

(m) our current report on Form 8-K filed with the Commission on July 2, 2007;

(n) our current report on Form 8-K filed with the Commission on July 6, 2007;

(o) our current report on Form 8-K filed with the Commission on July 25, 2007;

(p) our current report on Form 8-K filed with the Commission on September 10, 2007;

(q) our amended current report on Form 8-K/A filed with the Commission on September 11, 2007;

(r) our current report on Form 8-K filed with the Commission on October 17, 2007;

(s) our current report on Form 8-K filed with the Commission on October 24, 2007; and

(t) The description of the common stock contained in our registration statement on Form 8-A filed with the Commission on July 28, 2000, including any subsequent amendment or report filed for the purpose of updating such description.

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In addition, all documents we file pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act after the date of this registration statement and prior to the filing of a post-effective amendment that indicates that all securities offered hereby have been sold or that deregisters all securities then remaining unsold, are incorporated by reference in this registration statement and are a part hereof from the date of filing such documents. Any statement contained in a document incorporated or deemed to be incorporated by reference herein shall be deemed to be modified or superseded for purposes of this registration statement to the extent that a statement contained herein or in any other subsequently filed document which also is or is deemed to be incorporated by reference herein modifies or supersedes such statement. Any such statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this registration statement.

Item 4. Description of Securities .

Not applicable.

Item 5. Interests of Named Experts and Counsel .

Not applicable.

Item 6. Indemnification of Directors and Officers .

Article SEVENTH of our Third Amended and Restated Certificate of Incorporation, as amended to date, or the Charter, provides that no director of our company shall be personally liable to us or our stockholders for monetary damages for any breach of fiduciary duty as a director, notwithstanding any provision of law imposing such liability, except to the extent that the General Corporation Law of the State of Delaware prohibits the elimination or limitation of liability of directors for breaches of fiduciary duty.

Article EIGHTH of our Charter provides that each of our directors and officers (a) shall be indemnified by us against all expenses (including attorneys’ fees), judgments, fines and amounts paid in settlement incurred in connection with any litigation or other legal proceeding (other than an action by or in the right of us) threatened or brought against him by virtue of the fact that he is, or has agreed to serve as, a director or officer of our company or is serving in the position of director, officer, partner, employee or trustee of another corporation, partnership, joint venture trust or other enterprise on our behalf, if he acted in good faith and in a manner he reasonably believed to be in, or not opposed to, our best interests, and, with respect to any criminal action or proceeding, he had no reasonable cause to believe his conduct was unlawful and (b) shall be indemnified by us against all expenses (including attorneys’ fees) and amounts paid in settlement incurred in connection with any action by or in the right of us brought against him by virtue of the fact that he is, or has agreed to serve as, a director or officer of our company or is serving in the position of director, officer, partner, employee or trustee of another corporation, partnership, joint venture trust or other enterprise on our behalf, if he acted in good faith and in a manner he reasonably believed to be in, or not opposed to, our best interests, except that no indemnification shall be made with respect to any matter as to which such person shall have been adjudged to be liable to us, unless a court determines that, despite such adjudication but in view of all of the circumstances, he is entitled to indemnification of such expenses. Notwithstanding the foregoing, to the extent that a director or officer has been successful, on the merits or otherwise, including, without limitation, the dismissal of an action without prejudice, he is required to be indemnified by us against all expenses (including attorneys’ fees) incurred in connection therewith. Expenses shall be advanced to a director or officer at his request, provided that he undertakes to repay the amount advanced if it is ultimately determined that he is not entitled to indemnification for such expenses.

Indemnification is required to be made unless we determine that the applicable standard of conduct required for indemnification has not been met. In the event of a determination by us that the director or officer did not meet the applicable standard of conduct required for indemnification or if we fail to make an indemnification payment within 60 days after such payment is claimed by such person, such person is permitted to petition the court to make an independent determination as to whether such person is entitled

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to indemnification. As a condition precedent to the right of indemnification, the director or officer must give us notice of the action for which indemnity is sought and we have the right to participate in such action or assume the defense thereof.

Section 145 of the General Corporation Law of the State of Delaware provides that a corporation has the power to indemnify a director, officer, employee, or agent of the corporation and certain other persons serving at the request of the corporation in related capacities against expenses (including attorney’s fees), judgments, fines and amounts paid in settlement actually and reasonably incurred by the person in connection with any threatened, pending or completed action, suit or proceeding to which he was or is a party or is threatened to be made a party by reason of such position, if such person acted in good faith and in a manner he reasonably believed to be in or not opposed to the best interests of the corporation, and, in any criminal proceeding, if such person has no reasonable cause to believe his conduct was unlawful. In the case of actions brought by or in the right of the corporation, however, no indemnification shall be made with respect to any matter as to which such person shall have been adjudged to be liable to the corporation unless and only to the extent that the adjudicating court determines that, despite the adjudication of liability but in view of all the circumstances of the case, such person is fairly and reasonably entitled to indemnity for such expenses which the Court of Chancery or such other court shall deem proper.

We maintain a general liability insurance policy which covers certain liabilities of directors and officers of our corporation arising out of claims based on acts or omissions in their capacities as directors or officers.

At present, there is no pending litigation or proceeding involving any director, officer, employee or agent as to which indemnification will be required or permitted under the Charter. We are not aware of any threatened litigation or proceeding that may result in a claim for such indemnification.

Item 7. Exemption From Registration Claimed .

Not applicable.

Item 8. Exhibits .

The following is a list of exhibits filed as part of this registration statement, which are incorporated herein:

Exhibit
Number			Document
5.1			Opinion of Paul M. Antinori, Esq., Senior Vice President and General Counsel

10.1			The Medicines Company 2007 Equity Inducement Plan

23.1			Consent of Ernst & Young LLP

23.2			Consent of Paul M. Antinori, Esq., Senior Vice President and General Counsel (contained in Exhibit 5.1)

24.1			Power of Attorney (included in the signature page of this registration statement)

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Item 9. Undertakings .

(a) The undersigned registrant hereby undertakes:

(1) To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:

(i) To include any prospectus required by Section 10(a)(3) of the Securities Act of 1933;

(ii) To reflect in the prospectus any facts or events arising after the effective date of this registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in this registration statement;

(iii) To include any material information with respect to the plan of distribution not previously disclosed in this registration statement or any material change to such information in this registration statement;

provided, however , that the undertakings set forth in paragraphs (a)(1)(i) and (a)(1)(ii) above do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in periodic reports filed with or furnished to the Commission by the registrant pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in this registration statement.

(2) That, for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(3) To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

(b) The undersigned registrant hereby undertakes that, for purposes of determining any liability under the Securities Act of 1933, each filing of the registrant’s annual report pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing of an employee benefit plan’s annual report pursuant to Section 15(d) of the Securities Exchange Act of 1934) that is incorporated by reference in this registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(c) Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the Commission such indemnification is against public policy as expressed in the Securities Act of 1933 and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act of 1933 and will be governed by the final adjudication of such issue.

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SIGNATURES

Pursuant to the requirements of the Securities Act, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Parsippany, State of New Jersey, on this 9th day of January, 2008.

	THE MEDICINES COMPANY


	By:	/s/ Clive A. Meanwell
		Clive A. Meanwell
		Chairman and Chief Executive Officer

We, the undersigned officers and directors of The Medicines Company, hereby severally constitute and appoint Clive A. Meanwell, Glenn P. Sblendorio, John P. Kelley, and each of them singly, our true and lawful attorneys with full power to them, and each of them singly, to sign for us and in our names in the capacities indicated below, the registration statement on Form S-8 filed herewith and any and all subsequent amendments to said registration statement, and generally to do all such things in our names and on our behalf in our capacities as officers and directors to enable The Medicines Company to comply with the provisions of the Securities Act, and all requirements of the Securities and Exchange Commission, hereby ratifying and confirming out signatures as they may be signed by our said attorneys, or any of them, to said registration statement and any and all amendments thereto.

Pursuant to the requirements of the Securities Act, this registration statement has been signed below by the following persons in the capacities and on the date indicated.

Signature	Title(s)	Date

/s/ Clive A. Meanwell	Chief Executive Officer and Chairman of the	January 9, 2008
Clive A. Meanwell	Board of Directors (Principal Executive Officer)

/s/ Glenn P. Sblendorio	Executive Vice President, Chief Financial	January 7, 2008
Glenn P. Sblendorio	Officer and Treasurer (Principal Financial and
	Accounting Officer)

/s/ John P. Kelley	President, Chief Operating Officer and Director	January 7, 2008
John P. Kelley

/s/ William W. Crouse	Director	January 5, 2008
William W. Crouse

/s/ Robert J. Hugin	Director	January 9, 2008
Robert J. Hugin

/s/ T. Scott Johnson	Director	January 4, 2008
T. Scott Johnson

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/s/ Armin M. Kessler	Director	January 6, 2008
Armin M. Kessler

/s/ Hiroaki Shigeta	Director	January 6, 2008
Hiroaki Shigeta

/s/ Melvin K. Spigelman	Director	January 5, 2008
Melvin K. Spigelman

/s/ Elizabeth H.S. Wyatt	Director	January 5, 2008
Elizabeth H.S. Wyatt

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Index to Exhibits

Exhibit Number		Document
5.1		Opinion of Paul M. Antinori, Esq., Senior Vice President and General Counsel

10.1		The Medicines Company 2007 Equity Inducement Plan

23.1		Consent of Ernst & Young LLP

23.2		Consent of Paul M. Antinori, Esq., Senior Vice President and General Counsel (contained in Exhibit 5.1)

24.1		Power of Attorney (included in the signature page of this registration statement)

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Exhibit 5.1

January 10, 2008

The Medicines Company
8 Campus Drive
Parsippany, New Jersey 07054

Re: 2007 Equity Inducement Plan

Ladies and Gentlemen:

I am the Senior Vice President and General Counsel of The Medicines Company, a Delaware corporation (the “Company”) and have assisted in the preparation of a Registration Statement on Form S-8 (the “Registration Statement”) to be filed with the Securities and Exchange Commission (the “Commission”) under the Securities Act of 1933, as amended (the “Securities Act”), relating to 1,700,000 shares of common stock, $0.001 par value per share, of the Company (the “Shares”), to be issued under the Company’s 2007 Equity Inducement Plan (the “Plan”).

I have examined the Certificate of Incorporation and By-Laws of the Company, each as amended and restated to date, and originals, or copies certified to my satisfaction, of all pertinent records of the meetings of the directors and stockholders of the Company, the Registration Statement and such other documents relating to the Company as I have deemed material for the purposes of this opinion.

In my examination of the foregoing documents, I have assumed the genuineness of all signatures, the authenticity of all documents submitted to me as originals, the conformity to original documents of all documents submitted to me as certified, photostatic or other copies, the authenticity of the originals of any such documents and the legal competence of all signatories to such documents.

I assume that the appropriate action will be taken, prior to the offer and sale of the Shares in accordance with the Plan, to register and qualify the Shares for sale under all applicable state securities or “blue sky” laws.

I express no opinion herein as to the laws of any state or jurisdiction other than the state laws of the General Corporation Law of the State of Delaware and the federal laws of the United States of America.

It is understood that this opinion is to be used only in connection with the offer and sale of the Shares while the Registration Statement is in effect.

Please note that I am opining only as to the matters expressly set forth herein, and no opinion should be inferred as to any other matters.

Based on the foregoing, I am of the opinion that the Shares have been duly authorized for issuance and, when the Shares are issued and paid for in accordance with the terms and conditions of the Plan, the Shares will be validly issued, fully paid and nonassessable.

I hereby consent to the filing of this opinion with the Commission in connection with the Registration Statement in accordance with the requirements of Item 601(b)(5) of Regulation S-K under the Securities Act. In giving such consent, I do not hereby admit that I am in the category of persons whose consent is required under Section 7 of the Securities Act or the rules and regulations of the Commission.

	Very truly yours,

	/s/ Paul M. Antinori
	Paul M. Antinori
	Senior Vice President and General Counsel

Exhibit 10.1

THE MEDICINES COMPANY

2007 EQUITY INDUCEMENT PLAN

1. Purpose

The purpose of this 2007 Equity Inducement Plan (the “Plan”) of The Medicines Company, a Delaware corporation (the “Company”), is to advance the interests of the Company’s stockholders by enhancing the Company’s ability to attract, retain and motivate persons who are expected to make important contributions to the Company and by providing such persons with equity ownership opportunities and performance-based incentives that are intended to better align their interests with those of the Company’s stockholders. Except where the context otherwise requires, the term “Company” shall include any of the Company’s present or future parent or subsidiary corporations as defined in Sections 424(e) or (f) of the Internal Revenue Code of 1986, as amended, and any regulations promulgated thereunder (the “Code”) and any other business venture (including, without limitation, joint venture or limited liability company) in which the Company has a controlling interest, as determined by the Board of Directors of the Company (the “Board”).

2. Eligibility

Options, restricted stock awards, stock appreciation rights or other stock-based awards (each, an “Award”) may be granted under the Plan to any person who (a) was not previously an employee or director of the Company or (b) is commencing employment with the Company following a bona fide period of non-employment by the Company, as an inducement material to the individual’s entering into employment with the Company. Each person who has been granted an Award under the Plan shall be deemed a “Participant”.

3. Administration

(a) Administration by the Compensation Committee of the Board of Directors . The Plan will be administered by the Compensation Committee of the Board (the “Committee”) . The Administrator shall have authority to grant Awards and to adopt, amend and repeal such administrative rules, guidelines and practices relating to the Plan as it shall deem advisable. The Administrator may correct any defect, supply any omission or reconcile any inconsistency in the Plan or any Award in the manner and to the extent it shall deem expedient to carry the Plan into effect and it shall be the sole and final judge of such expediency. All decisions by the Administrator shall be made in the Administrator’s sole discretion and shall be final and binding on all persons having or claiming any interest in the Plan or in any Award. No director shall be liable for any action or determination relating to or under the Plan made in good faith.

(b) Board Award Granting Authority . To the extent permitted by applicable law and Nasdaq regulations, if the Committee is unable to grant an Award under the Plan for any reason, the Board, with a vote of the majority of “independent directors” of the Board (as defined under Nasdaq regulations), shall have the authority to grant such Award. All references in the Plan to the “Administrator” shall mean the Committee or, when applicable pursuant to this Section 3(b), a majority of independent directors of the Board.

4. Stock Available for Awards

(a) Number of Shares . Subject to adjustment under Section 9, Awards may be made under the Plan for up to 1,700,000 shares of common stock, $.001 par value per share, of the Company (the “Common Stock”). If any Award expires or is terminated, surrendered or canceled without having been fully exercised or is forfeited in whole or in part (including as the result of shares of Common Stock subject to such Award being repurchased by the Company at the original issuance price pursuant to a contractual repurchase right) or results in any Common Stock not being issued, the unused Common Stock covered by such Award shall again be available for the grant of Awards under the Plan. Shares issued under the Plan may consist in whole or in part of authorized but unissued shares or treasury shares.

5. Stock Options

(a) General . The Administrator may grant options to purchase Common Stock (each, an “Option”) and determine the number of shares of Common Stock to be covered by each Option, the exercise price of each Option and the conditions and limitations applicable to the exercise of each Option, including conditions relating to applicable federal or state securities laws, as it considers necessary or advisable. All Options granted under the Plan shall be Nonstatutory Stock Options (as hereinafter defined). A “Nonstatutory Stock Option” is an Option which is not intended to be an Incentive Stock Option within the meaning of Section 422 of the Code and the regulations promulgated thereunder.

(b) Exercise Price . The Administrator shall establish the exercise price at the time each Option is granted and specify it in the applicable option agreement; provided, however, that the exercise price shall be not less than 100% of the fair market value as determined by (or in a manner approved by) the Administrator at the time the Option is granted.

(c) Duration of Options . Each Option shall be exercisable at such times and subject to such terms and conditions as the Administrator may specify in the applicable option agreement; provided, however, that no Option will be granted for a term in excess of 10 years.

(d) Exercise of Option . Options may be exercised by delivery to the Company of a written notice of exercise signed by the proper person or by any other form of notice (including electronic notice) approved by the Administrator together with payment in full as specified in Section 5(e) for the number of shares for which the Option is exercised.

(e) Payment Upon Exercise. Common Stock purchased upon the exercise of an Option granted under the Plan shall be paid for as follows:

(1) in cash or by check, payable to the order of the Company;

(2) except as the Administrator may otherwise provide in an option agreement, by (i) delivery of an irrevocable and unconditional undertaking by a creditworthy broker to deliver promptly to the Company sufficient funds to pay the exercise price and any required tax withholding or (ii) delivery by the Participant to the Company of a copy of irrevocable and unconditional instructions to a creditworthy broker to promptly pay to the Company the exercise price and any required tax withholding;

(3) when the Common Stock is registered under the Exchange Act, by delivery of shares of Common Stock owned by the Participant valued at their fair market value as determined by (or in a manner approved by) the Administrator, provided (i) such method of payment is then permitted under applicable law, (ii) such Common Stock, if acquired directly from the Company, was owned by the Participant at least six months prior to such delivery and (iii) such Common Stock is not subject to any repurchase, forfeiture, unfulfilled vesting or other similar requirements;

(4) to the extent permitted by applicable law and by the Administrator, by (i) delivery of a promissory note of the Participant to the Company on terms determined by the Administrator, or (ii) payment of such other lawful consideration as the Administrator may determine; or

(5) by any combination of the above permitted forms of payment.

(f) Substitute Options . In connection with a merger or consolidation of an entity with the Company or the acquisition by the Company of property or stock of an entity, the Administrator may grant Options in substitution for any options or other stock or stock-based awards granted by such entity or an affiliate thereof prior to such merger, consolidation or acquisition. Substitute Options may be granted on such terms as the Administrator deems appropriate in the circumstances, notwithstanding any limitations on Options contained in the other sections of this Section 5 or in Section 2.

(g) No Repricing . Without prior stockholder approval, the Company may not engage in any repricing with respect to any Option or Options which requires stockholder approval under the rules of the Nasdaq National Market or the principal market on which the Company’s Common Stock is then traded.

(h) No Reload Rights . No Option granted under the Plan shall contain any provision entitling the optionee to the automatic grant of additional Options in connection with any exercise of the original Option.

6. Stock Appreciation Rights

(a) Nature of Stock Appreciation Rights . A Stock Appreciation Right is an Award entitling the holder on exercise to receive an amount in cash or Common Stock or a combination thereof (such form to be determined by the Administrator) determined in whole or in part by reference to appreciation, from and after the date of grant, in the fair market value of a share of Common Stock (an “SAR Award”). A Stock Appreciation Right may be based solely on appreciation in the fair market value of Common Stock or on a comparison of such appreciation with some other measure of market growth such as (but not limited to) appreciation in a recognized market index. The date as of which such appreciation or other measure is determined shall be the exercise date unless another date is specified by the Administrator in the SAR Award.

(b) Grants . Stock Appreciation Rights may be granted in tandem with, or independently of, Options granted under the Plan.

(1) Rules Applicable to Tandem Awards . When Stock Appreciation Rights are expressly granted in tandem with Options, the Stock Appreciation Right will be exercisable only at such time or times, and on such conditions, as the Administrator may specify in the SAR Award or the related Options.

(2) Exercise of Independent Stock Appreciation Rights . A Stock Appreciation Right not expressly granted in tandem with an Option will become exercisable at such time or times, and on such conditions, as the Administrator may specify in the SAR Award.

(c) Exercise . Any exercise of a Stock Appreciation Right must be in writing, signed by the proper person and delivered or mailed to the Company, accompanied by any other documents required by the Administrator.

7. Restricted Stock .

(a) Grants . The Administrator may grant Awards entitling recipients to acquire shares of Common Stock, subject to the right of the Company to repurchase all or part of such shares at their issue price or other stated or formula price (or to require forfeiture of such shares if issued at no cost) from the recipient in the event that conditions specified by the Administrator in the applicable Award are not satisfied prior to the end of the applicable restriction period or periods established by the Administrator for such Award (each, a “Restricted Stock Award”).

(b) Terms and Conditions . The Administrator shall determine the terms and conditions of a Restricted Stock Award, including the conditions for repurchase (or forfeiture) and the issue price, if any.

(c) Limitation on Vesting . Restricted Stock Awards shall not vest earlier than the first anniversary of the date of grant. Notwithstanding any other provision of this Plan, the Administrator may, in its discretion, either at the time a Restricted Stock Award is made or at any time thereafter, waive its right to repurchase shares of Common Stock (or waive the forfeiture thereof) or remove or modify any part or all of the restrictions applicable to the Restricted Stock Award, provided that the Administrator may only exercise such rights in extraordinary circumstances which shall include, without limitation, death or disability of the Participant; a merger, consolidation, sale, reorganization, recapitalization, or change in control of the Company; or any other nonrecurring significant event affecting the Company, a Participant or the Plan.

(d) Stock Certificates . Any stock certificates issued in respect of a Restricted Stock Award shall be registered in the name of the Participant and, unless otherwise determined by the Administrator, deposited by the Participant, together with a stock power endorsed in blank, with the Company (or its designee). At the expiration of the applicable restriction periods, the Company (or such designee) shall deliver the certificates no longer subject to such restrictions to the Participant or if the Participant has died, to the beneficiary designated, in a manner determined by the Administrator, by a Participant to receive amounts due or exercise rights of the Participant in the event of the Participant’s death (the “Designated Beneficiary”). In the

absence of an effective designation by a Participant, “Designated Beneficiary” shall mean the Participant’s estate.

8. Other Stock-Based Awards .

Other Awards of shares of Common Stock, and other Awards that are valued in whole or in part by reference to, or are otherwise based on, shares of Common Stock or other property, may be granted hereunder to Participants (“Other Stock Unit Awards”), including, without limitation, Awards entitling recipients to receive shares of Common Stock to be delivered in the future. Such Other Stock Unit Awards shall also be available as a form of payment in the settlement of other Awards granted under the Plan or as payment in lieu of compensation to which a Participant is otherwise entitled. Other Stock Unit Awards may be paid in shares of Common Stock or cash, as the Administrator shall determine. Subject to the provisions of the Plan, the Administrator shall determine the conditions of each Other Stock Unit Awards, including any purchase price applicable thereto. At the time any Award is granted, the Administrator may provide that, at the time Common Stock would otherwise be delivered pursuant to the Award, the Participant will instead receive an instrument evidencing the Participant’s right to future delivery of the Common Stock.

9. Adjustments for Changes in Common Stock and Certain Other Events .

(a) Changes in Capitalization . In the event of any stock split, reverse stock split, stock dividend, recapitalization, combination of shares, reclassification of shares, spin-off or other similar change in capitalization or event, or any distribution to holders of Common Stock other than an ordinary cash dividend, (i) the number and class of securities available under this Plan, (ii) the limits on Awards set forth in Section 4(a), (iii) the number and class of securities and exercise price per share subject to each outstanding Option, (iv) the repurchase price per share subject to each outstanding Restricted Stock Award and (v) the share- and per-share-related provisions of each outstanding Stock Appreciation Right and Other Stock Unit Award shall be appropriately adjusted by the Company (or substituted Awards may be made, if applicable) to the extent determined by the Administrator.

(b) Reorganization and Change in Control Events

(1) Definitions

(a) A “Reorganization Event” shall mean:

(i) any merger or consolidation of the Company with or into another entity as a result of which all of the Common Stock of the Company is converted into or exchanged for the right to receive cash, securities or other property;

(ii) any exchange of all of the Common Stock of the Company for cash, securities or other property pursuant to a share exchange transaction; or

(iii) any liquidation or dissolution of the Company.

(b) A “Change in Control Event” shall mean:

(i) any sale or transfer of all or substantially all of the assets of the Company to another corporation or entity, any merger, consolidation or reorganization of the Company into or with another corporation or entity, with the result that, upon conclusion of the transaction, the voting securities of the Company immediately prior thereto do not represent (either by remaining outstanding or by being converted into voting securities of the surviving entity) more than 50% of the combined voting power of the voting securities of the continuing or surviving entity of such consolidation, merger or reorganization; or

(ii) a disclosure that any person (as the term “person” is used in Section 13(d)(3) or Section 14(d)(2) of the Exchange Act), other than (A) the Company or (B) any corporation owned directly or indirectly by the stockholders of the Company in substantially the same proportion as their ownership of stock of the Company, becomes the beneficial owner as the term “beneficial owner” is defined under Rule 13d-3 or any successor rule or regulation thereto under the Exchange Act) of securities representing 30% or more of the combined voting power of the then outstanding voting securities of the Company; or

(iii) such time as individuals who as of the date of the initial adoption of this Plan constitute the Board of Directors of the Company, and any new director (other than a director designated by a person who has entered into an agreement with the Company to effect any transaction described in clause (i) or (ii) of this section) whose election by the Board or nomination for election by the Company’s stockholders was approved by a vote of at least two-thirds of the directors then still in office who were either directors at the beginning of the period or whose election or whose nomination for election was previously so approved, cease for any reason to constitute a majority of the Board of Directors; or

(iv) the liquidation or dissolution of the Company.

(c) “Cause” shall mean (i) conviction of any felony or any crime involving moral turpitude or dishonesty; (ii) participation in a fraud or act of dishonesty against the Company (or, if applicable, a successor corporation to the Company); (iii) willful and material breach of the Company’s policies (or, if applicable, a successor corporation to the

Company); (iv) intentional and material damage to the Company’s property (or, if applicable, a successor corporation to the Company); or (v) material breach of the Participant’s confidentiality obligations or duties under the Participant’s non-disclosure, non-competition or other similar agreement with the Company (or, if applicable, a successor corporation to the Company).

(d) “Termination Event” shall mean the termination of the Participant’s employment (i) by the Company or the acquiring or succeeding corporation without Cause; (ii) as a result of Participant’s death or disability (within the meaning of Section 22(4)(3) of the Code); or (iii) by the Participant upon written notice given promptly after the Company’s or the acquiring or succeeding corporation’s taking of any of the following actions, which actions shall not have been cured within a 30-day period following such notice: (A) the principal place of the performance of the Participant’s responsibilities (the “Principal Location”) is changed to a location outside of a 30 mile radius from the Principal Location immediately prior to the Reorganization Event; (B) there is a material reduction in the Participant’s responsibilities without Cause; (C) there is a material reduction in the Participant’s salary; or (D) there is a significant diminution in the scope of the Participant’s responsibilities without the Participant’s agreement (excluding increases in responsibility and sideways moves to jobs with similar descriptions).

(2) Effect on Options

(a) Reorganization Event . Upon the occurrence of a Reorganization Event (regardless of whether such event also constitutes a Change in Control Event), or the execution by the Company of any agreement with respect to a Reorganization Event (regardless of whether such event will result in a Change in Control Event), the Board shall provide that all outstanding Options shall be assumed, or equivalent options shall be substituted, by the acquiring or succeeding corporation (or an affiliate thereof); provided that if such Reorganization Event also constitutes a Change in Control Event, except to the extent specifically provided to the contrary in the instrument evidencing any Option or any other agreement between a Participant and the Company, such assumed or substituted options shall become immediately exercisable in full if, on or prior to the first anniversary of the date of the consummation of the Change in Control Event, a Termination Event occurs. For purposes hereof, an Option shall be considered to be assumed if, following consummation of the Reorganization Event, the Option confers the right to purchase, for each share of Common Stock subject to the Option immediately prior to the consummation of the Reorganization Event, the consideration (whether cash, securities or other property) received as a result of the Reorganization Event

by holders of Common Stock for each share of Common Stock held immediately prior to the consummation of the Reorganization Event (and if holders were offered a choice of consideration, the type of consideration chosen by the holders of a majority of the outstanding shares of Common Stock); provided, however, that if the consideration received as a result of the Reorganization Event includes but does not solely consist of common stock of the acquiring or succeeding corporation (or an affiliate thereof), the Company may, with the consent of the acquiring or succeeding corporation, provide for the consideration to be received upon the exercise of Options to consist solely of common stock of the acquiring or succeeding corporation (or an affiliate thereof) equivalent in fair market value to the per share consideration received by holders of outstanding shares of Common Stock as a result of the Reorganization Event.

Notwithstanding the foregoing, (i) if the acquiring or succeeding corporation (or an affiliate thereof) does not agree to assume, or substitute for, such Options, or in the event of a liquidation or dissolution of the Company, the Administrator shall, upon written notice to the Participants, provide that all then unexercised Options will become exercisable in full as of a specified time prior to the Reorganization Event and will terminate immediately prior to the consummation of such Reorganization Event, except to the extent exercised by the Participants before the consummation of such Reorganization Event, and (ii) in the event of a Reorganization Event under the terms of which holders of Common Stock will receive upon consummation thereof a cash payment for each share of Common Stock surrendered pursuant to such Reorganization Event (the “Acquisition Price”), the Administrator shall either (A) upon written notice to the Participants, provide that all then unexercised Options will become exercisable in full as of a specified time prior to the Reorganization Event and will terminate immediately prior to the consummation of such Reorganization Event, except to the extent exercised by the Participants before the consummation of such Reorganization Event or (B) provide that all outstanding Options shall terminate upon consummation of such Reorganization Event and that each Participant shall receive, in exchange therefor, a cash payment equal to the amount (if any) by which (x) the Acquisition Price multiplied by the number of shares of Common Stock subject to such outstanding Options (whether or not then exercisable), exceeds (y) the aggregate exercise price of such Options.

(b) Change in Control Event that is not a Reorganization Event . Upon the occurrence of a Change in Control Event that does not also constitute a Reorganization Event, except to the extent specifically

provided to the contrary in the instrument evidencing any Option or any other agreement between a Participant and the Company, each such Option shall become immediately exercisable in full if, on or prior to the first anniversary of the date of the consummation of the Change in Control Event, a Termination Event occurs.

(3) Effect on Restricted Stock Awards

(a) Reorganization Event that is not a Change in Control Event . Upon the occurrence of a Reorganization Event that is not a Change in Control Event, the repurchase and other rights of the Company under each outstanding Restricted Stock Award shall inure to the benefit of the Company’s successor and shall apply to the cash, securities or other property which the Common Stock was converted into or exchanged for pursuant to such Reorganization Event in the same manner and to the same extent as they applied to the Common Stock subject to such Restricted Stock Award.

(b) Change in Control Event . Upon the occurrence of a Change in Control Event (regardless of whether such event also constitutes a Reorganization Event), except to the extent specifically provided to the contrary in the instrument evidencing any Restricted Stock Award or any other agreement between a Participant and the Company, each such Restricted Stock Award shall immediately become free from all conditions or restrictions if, on or prior to the first anniversary of the date of the consummation of the Change in Control Event, a Termination Event occurs.

(4) Effect on Stock Appreciation Rights and Other Stock Unit Awards

The Administrator may specify in an Award at the time of the grant the effect of a Reorganization Event and Change in Control Event on any SAR Award and Other Stock Unit Award.

10. General Provisions Applicable to Awards

(a) Transferability of Awards . Except as the Administrator may otherwise determine or provide in an Award, Awards shall not be sold, assigned, transferred, pledged or otherwise encumbered by the person to whom they are granted, either voluntarily or by operation of law, except by will or the laws of descent and distribution or pursuant to a qualified domestic relations order, and, during the life of the Participant, shall be exercisable only by the Participant. References to a Participant, to the extent relevant in the context, shall include references to authorized transferees. Notwithstanding the foregoing, a Participant may transfer any Award by means of a gift to a family member (as such term is defined in General Instruction A to Form S-8, as may be amended from time to time) of such Participant, provided that prior written notice of such gift is provided to the Company.

(b) Documentation . Each Award shall be evidenced in such form (written, electronic or otherwise) as the Administrator shall determine. Each Award may contain terms and conditions in addition to those set forth in the Plan.

(c) Administrator Discretion . Except as otherwise provided by the Plan, each Award may be made alone or in addition or in relation to any other Award. The terms of each Award need not be identical, and the Administrator need not treat Participants uniformly.

(d) Termination of Status . The Administrator shall determine the effect on an Award of the disability, death, retirement, authorized leave of absence or other change in the employment or other status of a Participant and the extent to which, and the period during which, the Participant, or the Participant’s legal representative, conservator, guardian or Designated Beneficiary, may exercise rights under the Award.

(e) Withholding . Each Participant shall pay to the Company, or make provision satisfactory to the Company for payment of, any taxes required by law to be withheld in connection with Awards to such Participant pursuant to such rules and procedures as the Company may adopt. Except as the Administrator may otherwise provide in an Award, when the Common Stock is registered under the Exchange Act, Participants may satisfy such tax obligations in whole or in part by delivery of shares of Common Stock, including shares retained from the Award creating the tax obligation, valued at their fair market value as determined by (or in a manner approved by) the Administrator; provided, however, that the total tax withholding where stock is being used to satisfy such tax obligations cannot exceed the Company’s minimum statutory withholding obligations (based on minimum statutory withholding rates for federal and state tax purposes, including payroll taxes, that are applicable to such supplemental taxable income). Shares surrendered to satisfy tax withholding requirements cannot be subject to any repurchase, forfeiture, unfulfilled vesting or other similar requirements. The Company may, to the extent permitted by law, deduct any such tax obligations from any payment of any kind otherwise due to a Participant.

(f) Amendment of Award . Except as prohibited by Section 5(g), the Administrator may amend, modify or terminate any outstanding Award, including but not limited to, substituting therefor another Award of the same or a different type and changing the date of exercise or realization, provided that the Participant’s consent to such action shall be required unless the Administrator determines that the action, taking into account any related action, would not materially and adversely affect the Participant.

(g) Conditions on Delivery of Stock . The Company will not be obligated to deliver any shares of Common Stock pursuant to the Plan or to remove restrictions from shares previously delivered under the Plan until (i) all conditions of the Award have been met or removed to the satisfaction of the Company, (ii) in the opinion of the Company’s counsel, all other legal matters in connection with the issuance and delivery of such shares have been satisfied, including any applicable securities laws and any applicable stock exchange or stock market rules and regulations, and (iii) the Participant has executed and delivered to the Company such representations or agreements as the Company may consider appropriate to satisfy the requirements of any applicable laws, rules or regulations.

(h) Acceleration . The Administrator may at any time provide that any Award shall become immediately exercisable in full or in part, free of some or all restrictions or conditions, or otherwise realizable in full or in part, as the case may be.

(i) Deferrals . The Administrator may permit Participants to defer receipt of any Common Stock issuable upon exercise of an Option or upon the lapse of any restriction applicable to any Restricted Stock Award, subject to such rules and procedures as it may establish.

11. Miscellaneous

(a) No Right To Employment or Other Status . No person shall have any claim or right to be granted an Award, and the grant of an Award shall not be construed as giving a Participant the right to continued employment or any other relationship with the Company. The Company expressly reserves the right at any time to dismiss or otherwise terminate its relationship with a Participant free from any liability or claim under the Plan, except as expressly provided in the applicable Award.

(b) No Rights As Stockholder . Subject to the provisions of the applicable Award, no Participant or Designated Beneficiary shall have any rights as a stockholder with respect to any shares of Common Stock to be distributed with respect to an Award until becoming the record holder of such shares. Notwithstanding the foregoing, in the event the Company effects a split of the Common Stock by means of a stock dividend and the exercise price of and the number of shares subject to such Option are adjusted as of the date of the distribution of the dividend (rather than as of the record date for such dividend), then an optionee who exercises an Option between the record date and the distribution date for such stock dividend shall be entitled to receive, on the distribution date, the stock dividend with respect to the shares of Common Stock acquired upon such Option exercise, notwithstanding the fact that such shares were not outstanding as of the close of business on the record date for such stock dividend.

(c) Effective Date and Term of Plan . The Plan shall become effective on the date on which it is adopted by the Board. No Awards shall be granted under the Plan after the date of the Company’s 2008 Annual Meeting of Stockholders, provided that Awards granted prior to that date may extend beyond such date.

(d) Amendment of Plan . With the approval of the Board, at any time and from time to time, the Administrator may amend, suspend or terminate the Plan or any portion thereof at any time; provided that, to the extent determined by the Administrator, no amendment requiring stockholder approval under any applicable legal, regulatory or listing requirement shall become effective until such stockholder approval is obtained. No Award shall be made that is conditioned upon stockholder approval of any amendment to the Plan.

(e) Provisions for Foreign Participants . The Administrator may, without amending the Plan, modify Awards or Options granted to Participants who are foreign nationals or employed outside the United States or establish subplans under the Plan to recognize differences in laws, rules, regulations or customs of such foreign jurisdictions with respect to tax, securities, currency, employee benefit or other matters.

(f) Governing Law . The provisions of the Plan and all Awards made hereunder shall be governed by and interpreted in accordance with the laws of the State of Delaware, without regard to any applicable conflicts of law.

(g) Stockholder Approval Not Required . It is expressly intended that approval of the Company’s stockholders not be required as a condition of the effectiveness of the Plan, and the Plan’s provisions shall be interpreted in a manner consistent with such intent for all purposes and with NASD Rule 4350(i)(1)(A)(iv).

Exhibit 23.1

Consent of Independent Registered Public Accounting Firm

We consent to the incorporation by reference in the Registration Statement (Form S-8 No. 333-00000) pertaining to The Medicines Company 2007 Equity Inducement Plan of our reports dated February 23, 2007, with respect to the consolidated financial statements and schedule of The Medicines Company included in its Annual Report (Form 10-K) for the year ended December 31, 2006, The Medicines Company management’s assessment of the effectiveness of internal control over financial reporting, and the effectiveness of internal control over financial reporting of The Medicines Company filed with the Securities and Exchange Commission.

/s/ Ernst & Young LLP

MetroPark, New Jersey
January 7, 2008