8-K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM 8-K

CURRENT REPORT PURSUANT

TO SECTION 13 OR 15(d) OF THE

SECURITIES EXCHANGE ACT OF 1934

Date of report (Date of earliest event reported) May 14, 2007

ADVANCED MAGNETICS, INC.

(Exact name of registrant as specified in its charter)

Delaware

(State or other jurisdiction of incorporation)

0-14732	04-2742593
(Commission File Number)	(IRS Employer Identification No.)
125 CambridgePark Drive, 6th Floor
Cambridge, Massachusetts	02140
(Address of principal executive offices)	(Zip Code)

(617) 498-3300

(Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

¨ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

¨ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

¨ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

¨ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 5.02. Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

On May 14, 2007, the Board of Directors (the “Board”) of Advanced Magnetics, Inc. (the “Company”) voted to increase the compensation payable to Mark Skaletsky as a result of his appointment as the Chairman of the Board. Mr. Skaletsky will be paid an annual retainer of $60,000, payable in four equal quarterly installments, and it is intended that he will be granted an option to purchase $200,000 in value of shares of the Company’s common stock pursuant to the Company’s current equity incentive plan. The actual number of shares underlying the option to be granted will be determined using a Black-Scholes option pricing model identical to that used by the Company for purposes of preparing its financial statements. Such option will be granted at the same time as the other members of the Board receive their annual grant of stock options.  The option will be granted with an exercise price equal to the fair market value of the Company’s common stock on the date the option is granted.

On May 14, 2007, the Board voted to adopt new severance and change of control arrangements for the following executive officers of the Company: Brian J.G. Pereira, President and Chief Executive Officer, David Arkowitz, Chief Financial Officer and Chief Business Officer, Joseph L. Farmer, General Counsel and Vice President of Legal Affairs, Louis Brenner, Senior Vice President, and Timothy G. Healey, Senior Vice President of Commercial Operations. The employment agreements entered into with each of those officers will be amended to reflect the changes set forth below.

Severance Due After Termination of Employment.

In the event that the Company terminates the employment of any such executive officer, other than for death, disability or cause (as such term will be defined in the applicable amendment to the employment agreement), or such executive officer resigns for good reason (as such term will be defined in the applicable amendment to the employment agreement), and (i) such executive officer has complied with all his obligations under all agreements with the Company, and (ii) such executive officer signs a general release of claims in a form acceptable to the Company, then the Company has agreed to pay severance to such executive officer in an amount equal to 12 months of base salary (24 months in the case of Dr. Pereira), paid in equal installments over the severance period in accordance with the Company’s usual payroll schedule. This paragraph shall not apply during the one year period following a change of control (as such term will be defined in the applicable amendment to the employment agreement).

Payments and Benefits upon a Change of Control.

Upon the closing of a transaction that constitutes a change of control of the Company, 50% of the unvested outstanding options and/or restricted stock units then held by such executive officers other than Dr. Pereira, who has other prior arrangements with the Company as to the vesting of his stock options and restricted stock units, shall become vested. In addition, in the event that within one year from the date a change of control of the Company occurs, the Company or its successor terminates the employment of any such executive officer other than for death, disability or cause, or such executive officer resigns for good reason, and such executive officer (i) has complied with all his obligations under all agreements with the Company, and (ii)

signs a general release of claims in a form acceptable to the Company, then the Company has agreed to provide such executive officer with the following benefits post-termination:

- 12 months of base salary (24 months in the case of Dr. Pereira), paid in equal installments over the severance period in accordance with the Company’s usual payroll schedule;

- one time (two times in the case of Dr. Pereira) the average bonus paid to such executive officer during the prior three years; provided that in no event will a year prior to the year ended December 31, 2007 be used in the calculation;

- continuation of health and dental benefits until the earlier of (a) 24 months post termination and (b) health and dental coverage being provided to such officer under another employer’s health and dental plan; and

- the acceleration of vesting of any unvested outstanding stock options and restricted stock units that were granted before such change of control.

Item 5.03.  Amendments to Articles of Incorporation or Bylaws. Change in Fiscal Year.

On May 14, 2007, the Board voted to change the Company’s fiscal year end from September 30 to December 31.

On May 14, 2007, the Board voted to amend and restate the Amended and Restated Bylaws of the Company (the “Bylaws”) in order to effect the change to the Company’s fiscal year end as described above and to change the date of the Company’s Annual Meeting from the first Tuesday in February of each year to a date to be fixed by the Board of Directors of the Company.

The foregoing description of the amendments to the Company's Bylaws is not complete and is qualified in its entirety by reference to the copy of the Company’s Amended and Restated Bylaws attached hereto as Exhibit 3.1 and incorporated herein by reference.

Item 7.01.  Regulation FD Disclosure.

On April 11, 2007 the Company announced positive results from two additional Phase III clinical trials of ferumoxytol as an intravenous (IV) iron replacement therapeutic. These results were presented as posters at the National Kidney Foundation’s Spring Clinical Meeting in Orlando, Florida.A copy of the Company’s press release is furnished herewith as Exhibit 99.1.

Item 9.01.  Financial Statements and Exhibits.

(d) Exhibits.

	The Company hereby files the following exhibit:
	3.1	Amended and Restated Bylaws.
	The Company hereby furnishes the following exhibit:
.	99.1	Press Release dated April 11, 2007.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

ADVANCED MAGNETICS, INC.
By: /s/ Joseph L. Farmer
	Joseph L. Farmer
	General Counsel and Vice President of Legal Affairs

Date: May 16, 2007

EXHIBIT INDEX

Exhibit Number	Description
3.1	Amended and Restated Bylaws.
99.1	Press release, dated April 11, 2007.

EX-3.1

Exhibit 3.1

AMENDED AND RESTATED

BY-LAWS

OF

ADVANCED MAGNETICS, INC.

(Amended and Restated as of May 14, 2007)

ARTICLE 1 - STOCKHOLDERS

1.1Place Of Meetings. All meetings of stockholders shall be held at such place within or without the State of Delaware as may be designated from time to time by the Board of Directors or the President or, if not so designated, at the registered office of the corporation.

1.2Annual Meeting. The annual meeting of stockholders for the election of directors and for the transaction of such other business as may properly be brought before the meeting shall be held on a date to be fixed by the Board of Directors (which date shall not be a legal holiday in the place where the meeting is to be held) at the time and place to be fixed by the Board of Directors and stated in the notice of the meeting.

1.3Special Meetings. Special meetings of stockholders may be called at any time by the President or by the Board of Directors. Business transacted at any special meeting of stockholders shall be limited to matters relating to the purpose or purposes stated in the notice of meeting.

1.4Notice Of Meetings. Except as otherwise provided by law, written notice of each meeting of stockholders, whether annual or special, shall be given not less than 10 nor more than 60 days before the date of the meeting to each stockholder entitled to vote at such meeting. The notices of all meetings shall state the place, date and hour of the meeting. The notice of a special meeting shall state, in addition, the purpose or purposes for which the meeting is called. If mailed, notice is given when deposited in the United States mail, postage prepaid, directed to the stockholder at his address as it appears on the records of the corporation.

1.5Voting List. The officer who has charge of the stock ledger of the corporation shall prepare, at least 10 days before every meeting of stockholders, a complete list of the stockholders entitled to vote at the meeting, arranged in alphabetical order, and showing the address of each stockholder and the number of shares registered in the name of each stockholder. Such list shall be open to the examination of any stockholder, for any purpose germane to the meeting, during ordinary business hours, for a period of at least 10 days prior to the meeting, at a place within the city where the meeting is to be held. The list shall also be produced and kept at the time and place of the meeting during the whole time of the meeting, and may be inspected by any stockholder who is present.

1.6Quorum. Except as otherwise provided by law, the Certificate of Incorporation or these By-Laws, the holders of a majority of the shares of the capital stock of the corporation issued and outstanding and entitled to vote at the meeting, present in person or represented by proxy, shall constitute a quorum for the transaction of business.

1.7Adjournments. Any meeting of stockholders may be adjourned to any other time and to any other place at which a meeting of stockholders may be held under these By-Laws by the stockholders present or represented at the meeting and entitled to vote, although less than a quorum, or, if no stockholder is present, by any officer entitled to preside at or to act as Secretary of such meeting. It shall not be necessary to notify any stockholder of any adjournment of less than 30 days if the time and place of the adjourned meeting are announced at the meeting at which adjournment is taken, unless after the adjournment a new record date is fixed for the adjourned meeting. At the adjourned meeting, the corporation may transact any business which might have been transacted at the original meeting.

1.8Voting And Proxies. Each stockholder shall have one vote for each share of stock entitled to vote held of record by such stockholder and a proportionate vote for each fractional share so held, unless otherwise provided in the Certificate of Incorporation. Each stockholder of record entitled to vote at a meeting of stockholders, or to express consent or dissent to corporate action in writing without a meeting, may vote or express such consent or dissent in person or may authorize another person or persons to vote or act for him by written proxy executed by the stockholder or his authorized agent and delivered to the Secretary of the corporation. No such proxy shall be voted or acted upon after three years from the date of its execution, unless the proxy expressly provides for a longer period.

1.9Action At Meeting. When a quorum is present at any meeting, the holders of a majority of the stock present or represented and voting on a matter (or if there are two or more classes of stock entitled to vote as separate classes, then in the case of each such class, the holders of a majority of the stock of that class present or represented and voting on a matter) shall decide any matter to be voted upon by the stockholders at such meeting, except when a different vote is required by express provision of law, the Certificate of Incorporation or these By-Laws. Any election by stockholders shall be determined by a plurality of the votes cast by the stockholders entitled to vote at the election.

1.10Action Without Meeting. Any action required or permitted to be taken at any annual or special meeting of stockholders of the corporation may be taken without a meeting, without prior notice and without a vote, if a consent in writing, setting forth the action so taken, is signed by the holders of outstanding stock having not less than the minimum number of votes that would be necessary to authorize or take such action at a meeting at which all shares entitled to vote on such action were present and voted. Prompt notice of the taking of corporate action without a meeting by less than unanimous written consent shall be given to those stockholders who have not consented in writing.

ARTICLE 2 - DIRECTORS

2.1General Powers. The business and affairs of the corporation shall be managed by or under the direction of a Board of Directors, who may exercise all of the powers of the corporation except as otherwise provided by law, the Certificate of Incorporation or these By-Laws. In the event of a vacancy in the Board of Directors, the remaining directors, except as otherwise provided by law, may exercise the powers of the full Board until the vacancy is filled.

2.2Number; Election; Tenure And Qualification. The number of directors which shall constitute the whole Board shall be fixed by resolution of the Board of Directors, but in no event shall be less than one. Each director shall be elected by the stockholders at the annual

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meeting and shall hold office until the next annual meeting and until his successor is elected and qualified, or until his earlier death, resignation or removal. Directors need not be stockholders of the corporation.

2.3Enlargement Of The Board. The number of the Board of Directors may be increased at anytime by vote of a majority of the directors then in office.

2.4Vacancies. Unless and until filled by the stockholders, any vacancy in the Board of Directors, however occurring, including a vacancy resulting from an enlargement of the Board, may be filled by vote of a majority of the directors then in office, although less than a quorum, or by a sole remaining director. A director elected to fill a vacancy shall be elected for the unexpired term of his predecessor in office, and a director chosen to fill a position resulting from an increase in the number of directors shall hold office until the next annual meeting of stockholders and until his successor is elected and qualified, or until his earlier death, resignation or removal.

2.5Resignation. Any director may resign by delivering his written resignation to the corporation at its principal office or to the President or Secretary. Such resignation shall be effective upon receipt unless it is specified to be effective at some other time or upon the happening of some other event.

2.6Regular Meetings. Regular meetings of the Board of Directors may be held without notice at such time and place, either within or without the State of Delaware, as shall be determined from time to time by the Board of Directors; provided that any director who is absent when such a determination is made shall be given notice of the determination. A regular meeting of the Board of Directors may be held without notice immediately after and at the same place as the annual meeting of stockholders. Notice to any such director not attending the meeting shall be given in person, by telephone, by telegram sent to his business or home address or by other electronic transmission directed as instructed by such director at least 48 hours in advance of the meeting, or by written notice mailed to his business or home address at least 72 hours in advance of the scheduled meeting.

2.7Special Meetings. Special meetings of the Board of Directors may be held at any time and place, within or without the State of Delaware, designated in a call by the Chairman of the Board, President, two or more directors, or by one director in the event that there is only a single director in office.

2.8Notice Of Special Meetings. Notice of any special meeting of directors shall be given to each director by the Secretary or by the officer or one of the directors calling the meeting. Notice shall be given to each director in person, by telephone, by telegram sent to his business or home address or by other electronic transmission directed as instructed by such director at least 48 hours in advance of the meeting, or by written notice mailed to his business or home address at least 72 hours in advance of the meeting. A notice or waiver of notice of a meeting of the Board of Directors need not specify the purposes of the meeting.

2.9Meetings By Telephone Conference Calls. Directors or any members of any committee designated by the directors may participate in a meeting of the Board of Directors or such committee by means of conference telephone or similar communications equipment by

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means of which all persons participating in the meeting can hear each other, and participation by such means shall constitute presence in person at such meeting.

2.10Quorum. A majority of the number of directors fixed pursuant to Section 2.2 shall constitute a quorum at all meetings of the Board of Directors. In the event one or more of the directors shall be disqualified to vote at any meeting, then the required quorum shall be reduced by one for each such director so disqualified; provided, however, that in no case shall less than one-third (1/3) of the number so fixed constitute a quorum. In the absence of a quorum at any such meeting, a majority of the directors present may adjourn the meeting from time to time without further notice other than announcement at the meeting, until a quorum shall be present.

2.11Action At Meeting. At any meeting of the Board of Directors at which a quorum is present, the vote of a majority of those present shall be sufficient to take any action, unless a different vote is specified by law, the Certificate of Incorporation or these By-Laws.

2.12Action By Consent. Any action required or permitted to be taken at any meeting of the Board of Directors or of any committee of the Board of Directors may be taken without a meeting, if all members of the Board or committee, as the case may be, consent to the action in writing or by electronic transmission, and the written consents or electronic transmissions are filed with the minutes of proceedings of the Board or committee. Such filing shall be in paper form if the minutes are maintained in paper form and shall be in electronic form if the minutes are maintained in electronic form.

2.13Removal. Any one or more or all of the directors may be removed, with or without cause, by the holders of a majority of the shares then entitled to vote at an election of directors.

2.14Committees. The Board of Directors may, by resolution passed by a majority of the whole Board, designate one or more committees, each committee to consist of one or more of the directors of the corporation. The Board may designate one or more directors as alternate members of any committee, who may replace any absent or disqualified member at any meeting of the committee. In the absence or disqualification of a member of the committee, the member or members of the committee present at any meeting and not disqualified from voting, whether or not he or they constitute a quorum, may unanimously appoint another member of the Board of Directors to act at the meeting in the place of any such absent or disqualified member. Any such committee, to the extent provided in the resolution of the Board of Directors and subject to the provisions of the General Corporation Law of the State of Delaware, shall have and may exercise all the powers and authority of the Board of Directors in the management of the business and affairs of the corporation and may authorize the seal of the corporation to be affixed to all papers which may require it. Each such committee shall keep minutes and make such reports as the Board of Directors may from time to time request. Except as the Board of Directors may otherwise determine, any committee may make rules for the conduct of its business, but unless otherwise provided by the directors or in such rules, its business shall be conducted as nearly as possible in the same manner as is provided in these By-Laws for the Board of Directors.

2.15Compensation Of Directors. Directors may be paid such compensation for their services and such reimbursement for expenses of attendance at meetings as the Board of Directors may from time to time determine. No such payment shall preclude any director from

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serving the corporation or any of its parent or subsidiary corporations in any other capacity and receiving compensation for such service.

ARTICLE 3 - OFFICERS

3.1Enumeration. The officers of the corporation shall consist of a President, a Secretary, a Treasurer and such other officers with such other titles as the Board of Directors shall determine, including a Chairman of the Board, a Vice-Chairman of the Board, and one or more Vice Presidents, Assistant Treasurers, and Assistant Secretaries. The Board of Directors may appoint such other officers as it may deem appropriate.

3.2Election. The President, Treasurer and Secretary shall be elected annually by the Board of Directors at its first meeting following the annual meeting of stockholders. Other officers may be appointed by the Board of Directors at such meeting or at any other meeting.

3.3Qualification. The President shall be a director. No officer need be a stockholder. Any two or more offices may be held by the same person.

3.4Tenure. Except as otherwise provided by law, by the Certificate of Incorporation or by these By-Laws, each officer shall hold office until his successor is elected and qualified, unless a different term is specified in the vote choosing or appointing him, or until his earlier death, resignation or removal.

3.5Resignation And Removal. Any officer may resign by delivering his written resignation to the corporation at its principal office or to the President or Secretary. Such resignation shall be effective upon receipt unless it is specified to be effective at some other time or upon the happening of some other event.

The Board of Directors, or a committee duly authorized to do so, may remove any officer with or without cause. Except as the Board of Directors may otherwise determine, no officer who resigns or is removed shall have any right to any compensation as an officer for any period following his resignation or removal, or any right to damages on account of such removal, whether his compensation be by the month or by the year or otherwise, unless such compensation is expressly provided in a duly authorized written agreement with the corporation.

3.6Vacancies. The Board of Directors may fill any vacancy occurring in any office for any reason and may, in its discretion, leave unfilled for such period as it may determine any offices other than those of President, Treasurer and Secretary. Each such successor shall hold office for the unexpired term of his predecessor and until his successor is elected and qualified, or until his earlier death, resignation or removal.

3.7Chairman Of The Board And Vice-Chairman Of The Board. If the Board of Directors appoints a Chairman of the Board, he shall perform such duties and possess such powers as are assigned to him by the Board of Directors. If the Board of Directors appoints a Vice-Chairman of the Board, he shall, in the absence or disability of the Chairman of the Board, perform the duties and exercise the powers of the Chairman of the Board and shall perform such other duties and possess such other powers as may from time to time be vested in him by the Board of Directors.

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3.8President. The President shall be the chief operating officer of the corporation. He shall also be the chief executive officer of the corporation unless such title is assigned to a Chairman of the Board. The President shall, subject to the direction of the Board of Directors, have general charge and supervision of the business of the corporation. Unless otherwise provided by the Board of Directors, he shall preside at all meetings of the stockholders and of the Board of Directors (except as provided in Section 3.7 above). The President shall perform such other duties and shall have such other powers as the Board of Directors may from time to time prescribe.

3.9Vice Presidents. Any Vice President shall perform such duties and possess such powers as the Board of Directors or the President may from time to time prescribe. In the event of the absence, inability or refusal to act of the President, the Vice President (or if there shall be more than one, the Vice Presidents in the order determined by the Board of Directors) shall perform the duties of the President and when so performing shall have all the powers of and be subject to all the restrictions upon the President. The Board of Directors may assign to any Vice President the title of Executive Vice President, Senior Vice President or any other title selected by the Board of Directors.

3.10Secretary And Assistant Secretaries. The Secretary shall perform such duties and shall have such powers as the Board of Directors or the President may from time to time prescribe. In addition, the Secretary shall perform such duties and have such powers as are incident to the office of the secretary, including without limitation the duty and power to give notices of all meetings of stockholders and special meetings of the Board of Directors, to attend all meetings of stockholders and the Board of Directors and keep a record of the proceedings, to maintain a stock ledger and prepare lists of stockholders and their addresses as required, to be custodian of corporate records and the corporate seal and to affix and attest to the same on documents.

Any Assistant Secretary shall perform such duties and possess such powers as the Board of Directors, the President or the Secretary may from time to time prescribe. In the event of the absence, inability or refusal to act of the Secretary, the Assistant Secretary, (or if there shall be more than one, the Assistant Secretaries in the order determined by the Board of Directors) shall perform the duties and exercise the powers of the Secretary.

In the absence of the Secretary or any Assistant Secretary at any meeting of stockholders or directors, the person presiding at the meeting shall designate a temporary secretary to keep a record of the meeting.

3.11Treasurer And Assistant Treasurers. The Treasurer shall perform such duties and shall have such powers as may from time to time be assigned to him by the Board of Directors or the President. In addition, the Treasurer shall perform such duties and have such powers as are incident to the office of treasurer, including without limitation the duty and power to keep and be responsible for all funds and securities of the corporation, to deposit funds of the corporation in depositories selected in accordance with these By-Laws, to disburse such funds as ordered by the Board of Directors, to make proper accounts of such funds, and to render as required by the Board of Directors statements of all such transactions and of the financial condition of the corporation.

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The Assistant Treasurer shall perform such duties and possess such powers as the Board of Directors, the President or the Treasurer may from time to time prescribe. In the event of the absence, inability or refusal to act of the Treasurer, the Assistant Treasurer, (or if there shall be more than one, the Assistant Treasurers in the order determined by the Board of Directors) shall perform the duties and exercise the powers of the Treasurer.

3.12Bonded Officers. The Board of Directors may require any officer to give the corporation a bond in such sum and with such surety or sureties as shall be satisfactory to the Board of Directors upon such terms and conditions as the Board of Directors may specify, including without limitation a bond for the faithful performance of his duties and for the restoration to the corporation of all property in his possession or under his control belonging to the corporation.

3.13Salaries. Officers of the corporation shall be entitled to such salaries, compensation or reimbursement as shall be fixed or allowed from time to time by the Board of Directors.

ARTICLE 4 - CAPITAL STOCK

4.1Issuance Of Stock. Unless otherwise voted by the stockholders and subject to the provisions of the Certificate of Incorporation, the whole or in part of any unissued balance of the authorized capital stock of the corporation or the whole or any part of any unissued balance of the authorized capital stock of the corporation held in its treasury may be issued, sold, transferred or otherwise disposed of by vote of the Board of Directors in such manner, for such consideration and on such terms as the Board of Directors may determine.

4.2Certificates Of Stock. Every holder of stock of the corporation shall be entitled to have a certificate, in such form as may be prescribed by law and by the Board of Directors, certifying the number and class of shares owned by him in the corporation. Each such certificate shall be signed by, or in the name of the corporation by, the Chairman or Vice-Chairman, if any, of the Board of Directors, or the President or a Vice President, and the Treasurer or an Assistant Treasurer, or the Secretary or an Assistant Secretary of the corporation. Any or all of the signatures on the certificate may be a facsimile.

Each certificate for shares of stock which are subject to any restriction on transfer pursuant to the Certificate of Incorporation, the By-Laws, applicable securities laws or any agreement among any number of shareholders or among such holders and the corporation shall have conspicuously noted on the face or back of the certificate either the full text of the restriction or a statement of the existence of such restriction.

4.3Transfers. Subject to the restrictions, if any, stated or noted on the stock certificates, shares of stock may be transferred on the books of the corporation by the surrender to the corporation or its transfer agent of the certificate representing such shares properly endorsed or accompanied by a written assignment or power of attorney properly executed, and with such proof of authority or the authenticity of signature as the corporation or its transfer agent may reasonably require. Except as may be otherwise required by law, by the Certificate of Incorporation or by these By-Laws, the corporation shall be entitled to treat the record holder of stock as shown on its books as the owner of such stock for all purposes, including the payment of dividends and the right to vote with respect to such stock, regardless of any transfer, pledge or

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other disposition of such stock until the shares have been transferred on the books of the corporation in accordance with the requirements of these By-Laws.

4.4Lost, Stolen Or Destroyed Certificates. The corporation may issue a new certificate of stock in place of any previously issued certificate alleged to have been lost, stolen, or destroyed, upon such terms and conditions as the Board of Directors may prescribe, including the presentation of reasonable evidence of such loss, theft or destruction and the giving of such indemnity as the Board of Directors may require for the protection of the corporation or any transfer agent or registrar.

4.5Record Date. The Board of Directors may fix in advance a date as a record date for the determination of the stockholders entitled to notice of or to vote at any meeting of stockholders or to express consent (or dissent) to corporate action in writing without a meeting, or entitled to receive payment of any dividend or other distribution or allotment of any rights in respect of any change, conversion or exchange of stock, or for the purpose of any other lawful action. Such record date shall not be more than 60 nor less than 10 days before the date of such meeting, nor more than 60 days prior to any other action to which such record date relates.

If no record date is fixed, the record date for determining stockholders entitled to notice of or to vote at a meeting of stockholders shall be at the close of business on the day before the day on which notice is given, or, if notice is waived, at the close of business on the day before the day on which the meeting is held. The record date for determining stockholders entitled to express consent to corporate action in writing without a meeting, when no prior action by the Board of Directors is necessary, shall be the day on which the first written consent is expressed. The record date for determining stockholders for any other purpose shall be at the close of business on the day on which the Board of Directors adopts the resolution relating to such purpose.

A determination of stockholders of record entitled to notice of or to vote at a meeting of stockholders shall apply to any adjournment of the meeting; provided, however, that the Board of Directors may fix a new record date for the adjourned meeting.

ARTICLE 5

(Intentionally Omitted)

ARTICLE 6 - GENERAL PROVISIONS

6.1Fiscal Year. Except as from time to time otherwise designated by the Board of Directors, the fiscal year of the corporation shall begin on the first day of January in each year and end on the last day of December in each year.

6.2Corporate Seal. The corporate seal shall be in such form as shall be approved by the Board of Directors.

6.3Execution Of Instruments. The President or the Treasurer shall have power to execute and deliver on behalf and in the name of the corporation any instrument requiring the signature of an officer of the corporation, except as otherwise provided in these By-Laws, or where the execution and delivery of such an instrument shall be expressly delegated by the Board of Directors to some other officer or agent of the corporation.

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6.4Waiver Of Notice. Whenever any notice whatsoever is required to be given by law, by the Certificate of Incorporation or by these By-Laws, a waiver of such notice either in writing signed by the person entitled to such notice or such person's duly authorized attorney, or by telegraph, cable, or electronic transmission or any other available method, whether before, at or after the time stated in such waiver, or the appearance of such person or persons at such meeting in person or by proxy, shall be deemed equivalent to such notice; provided that a shareholder shall not be deemed to have received notice if that shareholder attends a meeting for the express purpose of objecting, at the beginning of the meeting, to the transaction of any business because the meeting is not lawfully called or convened.

6.5Voting Of Securities. Except as the directors may otherwise designate, the President or Treasurer may waive notice of, and act as, or appoint any person or persons to act as, proxy or attorney-in-fact for this corporation (with or without power of substitution) at, any meeting of stockholders or shareholders or any other corporation or organization, the securities of which may be held by this corporation.

6.6Evidence Of Authority. A certificate by the Secretary, or an Assistant Secretary, or a temporary Secretary, as to any action taken by the stockholders, directors, a committee or any officer or representative of the corporation shall as to all persons who rely on the certificate in good faith be conclusive evidence of such action.

6.7Certificate Of Incorporation. All references in these By-Laws to the Certificate of Incorporation shall be deemed to refer to the Certificate of Incorporation of the corporation, as amended and in effect from time to time.

6.8Transactions With Interested Parties. No contract or transaction between the corporation and one or more of the directors or officers, or between the corporation and any other corporation, partnership, association, or other organization in which one or more of the directors or officers are directors or officers, or have a financial interest, shall be void or voidable solely for this reason, or solely because the director or officers is present at or participates in the meeting of the Board of Directors or a committee of the Board of Directors which authorizes the contract or transaction or solely because his or their votes are counted for such purpose, if:

(1) The material facts as to his relationship or interest and as to the contract or transaction are disclosed or are known to the Board of Directors or the committee, and the Board or committee in good faith authorizes the contract or transaction by the affirmative votes of a majority of the disinterested directors, even though the disinterested directors be less than a quorum;

(2) The material facts as to his relationship or interest, and as to the contract or transaction are disclosed or are known to the stockholders entitled to vote thereon, and the contract or transaction is specifically approved in good faith by vote of the stockholders; or

(3) The contract or transaction is fair as to the corporation as of the time it is authorized, approved or ratified, by the Board of Directors, a committee of the Board of Directors, or the stockholders.

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Common or interested directors may be counted in determining the presence of a quorum at a meeting of the Board of Directors or of a committee which authorizes the contract or transaction.

6.9Severability. Any determination that any provision of these By-Laws is for any reason inapplicable, illegal or ineffective shall not affect or invalidate any other provision of these By-Laws.

6.10Pronouns. All pronouns used in these By-Laws shall be deemed to refer to the masculine, feminine or neuter, singular or plural, as the identity of the person or persons may require.

6.11Electronic Transmission. Any vote, notification or other action to be made by the Corporation or its officers, directors, agents or stockholders may be taken via an electronic transmission or other similar method of communication to the fullest extent permitted by the Delaware General Corporation Law, as amended.

ARTICLE 7 - AMENDMENTS

7.1By The Board Of Directors. These By-Laws may be altered, amended or repealed or new by-laws may be adopted by the affirmative vote of a majority of the directors present at any regular or specific meeting of the Board of Directors at which a quorum is present.

7.2By The Stockholders. These By-Laws may be altered, amended or repealed or new by-laws may be adopted by the affirmative vote of the holders of a majority of the shares of the capital stock of the corporation issued and outstanding and entitled to vote at any regular meeting of stockholders, or at any special meeting of stockholders, provided notice of such alteration, amendment, repeal or adoption of new by-laws shall have been stated in the notice of such special meeting.

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EX-99

Exhibit 99.1

FOR IMMEDIATE RELEASE

Contacts:

Kristen Galfetti (investors)

kgalfetti@advancedmagnetics.com

(617) 498-3362

Lynn Kettleson (media)

lkettleson@clarkecommgroup.com

(978) 463-7952

ADVANCED MAGNETICS ANNOUNCES POSITIVE RESULTS FROM TWO ADDITIONAL PHASE III

STUDIES OF FERUMOXYTOL AS AN INTRAVENOUS IRON REPLACEMENT THERAPEUTIC

CAMBRIDGE, MA (April 11, 2007) - Advanced Magnetics (NASDAQ: AMAG) today announced positive results from two additional Phase III clinical trials of ferumoxytol as an intravenous (IV) iron replacement therapeutic that are being presented today at approximately 6:00 pm EDT as posters at the National Kidney Foundation’s Spring Clinical Meeting in Orlando, Florida. These posters are available in the investor section on the company’s web site at www.advancedmagnetics.com.

The first poster, “Evaluation of the Efficacy and Safety of Ferumoxytol as an Intravenous Iron Replacement Therapy in Chronic Kidney Disease (CKD) Patients Not on Dialysis” shows results from 303 non-dialysis dependent CKD patients who were randomized to receive either two 510 mg doses of ferumoxytol within one week or 200 mg of oral iron daily for three weeks. This Phase III study demonstrated a statistically significant achievement of all primary and secondary endpoints. Additionally, all primary and secondary endpoints were achieved with statistical significance in both patients on erythropoiesis stimulating proteins (ESP) and those not on ESPs. These new results are consistent with the results previously presented at the American Society of Nephrology’s Renal Week in San Diego, CA in November 2006 from another study in non-dialysis dependent CKD patients with an identical protocol.

The second poster, “Evaluation of the Safety of Intravenous Ferumoxytol for Iron Replacement Therapy in Chronic Kidney Disease (CKD)” shows results from a double-blind, placebo-controlled, crossover Phase III study which enrolled a total of 750 patients, including both dialysis-dependent CKD patients and non-dialysis dependent CKD patients, who received either one 510 mg dose of ferumoxytol or IV placebo (saline) at day zero and received the other treatment at day seven. The primary safety analysis was the descriptive comparison of adverse events (AEs) experienced during ferumoxytol and placebo administration. Treatment related AEs occurred in 37 patients (5.2%) after ferumoxytol treatment and in 30 patients (4.2%) after placebo treatment. Treatment related serious adverse events (SAEs), as determined by the investigator, occurred in one patient (0.1%) after ferumoxytol treatment and in one patient (0.1%) after placebo treatment.

“The data from these studies are very promising because they demonstrate a statistically significant improvement in hemoglobin levels for non-dialysis dependent CKD patients undergoing ferumoxytol therapy as compared to oral iron therapy. In my opinion, the results from these two new studies, in conjunction with previous clinical trials, support an attractive profile for ferumoxytol,” stated Allen Nissenson, MD, Professor of Medicine and Director of the Dialysis Program at David Geffen School of Medicine at UCLA and Chair of the Ferumoxytol Scientific Advisory Board.

“We are very pleased with the results that we are presenting today at the National Kidney Foundation meeting,” stated Brian J.G. Pereira, MD, President and CEO of Advanced Magnetics. “We have now presented data from three of the four studies in the pivotal program for ferumoxytol. These new results are encouraging, and we remain on track to file our NDA for ferumoxytol in the fourth calendar quarter of 2007.”

Efficacy and Safety Study in Non-Dialysis DependentCKD Poster

The first poster shows results from the second of two efficacy and safety studies in non-dialysis dependent CKD patients (Protocol 62,745-7; ClinicalTrials.gov identifier NCT00255437). Efficacy results in the intent to treat (ITT) and efficacy evaluable populations were similar. Efficacy results from the ITT analysis showed:

·   For the primary endpoint, which is change in hemoglobin from baseline at Day 35, patients receiving ferumoxytol had a significantly greater mean increase in hemoglobin compared to patients receiving oral iron (ferumoxytol 1.24 ± 1.25 g/dl vs. oral iron 0.50 ± 0.98 g/dl, p<0.0001).

·   Ferumoxytol was more likely to increase baseline hemoglobin by ≥ 1 g/dl compared to oral iron (52.9% of ferumoxytol patients vs. 18.2% of oral iron patients, p<0.0001).

·   Mean increase in serum ferritin from baseline was significantly greater in the ferumoxytol group compared to the oral iron group at Day 21 (ferumoxytol 416.0 ± 249.0 ng/ml vs. oral iron 4.3 ± 48.2 ng/ml, p<0.0001).

·   Stratifying by ESP use, there was a significantly greater increase in hemoglobin at Day 35 for ferumoxytol compared to oral iron in both patients who were on ESPs and those who were not on ESPs.

·   In patients on a stable ESP dose, mean hemoglobin increase at Day 35 was 1.66 ± 1.38 g/dl for ferumoxytol compared to 0.82 ± 1.28 g/dl for oral iron (p=0.0024). In addition, 66.3% of patients treated with ferumoxytol experienced an increase of ≥ 1 g/dl in hemoglobin compared to 35.3% of patients treated with oral iron (p=0.0017).

·   Similarly, in patients not treated with ESPs, mean hemoglobin increase at Day 35 was 0.93 ± 1.05 g/dl for ferumoxytol compared to 0.25 ± 0.56 g/dl for oral iron (p<0.0001). In addition, 43.1% of patients treated with ferumoxytol alone experienced an increase of ≥ 1 g/dl in hemoglobin compared to 4.7% of patients treated with oral iron alone (p<0.0001).

Ferumoxytol was well tolerated with repeated dosing (2 x 510 mg). Adverse events occurred in 55.5% of ferumoxytol patients compared to 59.5% of oral iron patients. Drug-related adverse events occurred in 21.4% of ferumoxytol patients compared to 16.2% of oral iron patients. Serious adverse events occurred in 7.7% of ferumoxytol patients compared to 13.5% of oral iron

patients. There were no drug-related SAEs in ferumoxytol treated patients. There was one drug-related SAE in one oral iron treated patient (1.4%); a case of severe gastritis which led to discontinuation of the study drug.

Safety Study in CKD Poster

The second poster shows results from a double-blind, placebo-controlled, crossover safety study in dialysis- dependent CKD and non-dialysis dependent CKD patients (Protocol 62,745-8; ClinicalTrials.gov identifier NCT00255450). Complete safety data was available for 360 patients randomized to the ferumoxytol to placebo sequence and for 362 patients randomized to the placebo to ferumoxytol sequence. For the ferumoxytol to placebo sequence, 40.3% of patients had dialysis-dependent CKD, and for the placebo to ferumoxytol sequence 43.6% of patients had dialysis-dependent CKD. The results from this safety study showed:

·   There were no meaningful mean changes in vital signs on laboratory values from baseline for patients after either ferumoxytol or placebo administration.

·   AEs occurred in 21.3% of patients after ferumoxytol administration and in 16.3% of patients after placebo administration. On a blinded basis, these were deemed to be related to treatment by the investigator in 5.2% of patients after ferumoxytol and in 4.2% of patients after placebo.

·   SAEs occurred in 2.9% of patients after ferumoxytol administration and in 1.8% of patients after placebo administration. On a blinded basis, these SAEs were deemed to be related to treatment by the investigator in one patient (0.1%) after ferumoxytol and in one patient (0.1%) after placebo.

·   The single SAE attributed to the drug after ferumoxytol administration occurred in an 85 year-old male, with non-dialysis dependent CKD, hypertension, coronary artery disease, cerebrovascular disease and a history of multiple drug allergies to ciprofloxacin, levofloxacin, and percocet. The patient experienced an anaphylactoid reaction with severe hypotension a few minutes after ferumoxytol administration, was treated with subcutaneous epinephrine and recovered without sequelae.

·   The single SAE attributed to the drug after placebo administration occurred in an 81 year-old female, with non-dialysis dependent CKD, hypertension, atrial fibrillation, oxygen-dependent chronic obstructive pulmonary disease, hypothryroidism and gout. The patient developed a petechial rash one day after placebo administration, was withdrawn from the study and did not receive ferumoxytol.

The combined data from three of the four Phase III studies for which results are now available represent a total of approximately 1,588 administrations of 510 mg of ferumoxytol in 1,151 patients (protocols 62,745-6; 62,745-7; and 62,745-8). One of 1,151 patients (0.09%) experienced a drug related SAE after ferumoxytol treatment compared to one of 149 patients (0.67%) treated with oral iron and one of 716 patients (0.14%) treated with IV saline (placebo).

Conference Call Information

The company will host a conference call at 4:30 pm EDT today to discuss and answer questions regarding the data from the completed ferumoxytol studies and the status of the ferumoxytol clinical development program.

To listen to this conference call via audio webcast, please visit the Investors section of the Advanced Magnetics website at www.advancedmagnetics.com. The web cast will also be

available as a replay starting approximately one hour after the call is finished through July 11, 2007. Alternatively, to access the call via live telephone, please dial (800) 909-5202. Internationally, the call may be accessed by dialing (785) 830-7975. The confirmation call for this call is 2603141.

Replay information will be published by the company following this call.

About Ferumoxytol

Ferumoxytol, the company’s key product candidate, is being developed for use as an intravenous iron replacement therapeutic for the treatment of iron deficiency anemia in chronic kidney disease. The company plans to file a New Drug Application for marketing approval of ferumoxytol with the U.S. Food and Drug Administration during the fourth calendar quarter of 2007.

About Advanced Magnetics

Advanced Magnetics, Inc. is a developer of superparamagnetic iron oxide nanoparticles used in pharmaceutical products. As a leader in our field, we are dedicated to the development and commercialization of our proprietary nanoparticle technology for use in therapeutic iron compounds to treat anemia, as well as novel imaging agents to aid in the diagnosis of cancer and cardiovascular disease. For more information about Advanced Magnetics, please visit our website at http://www.advancedmagnetics.com, the content of which is not part of this press release.

Forward-looking Statement

This document contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995 and federal securities laws. Any statements contained in this press release that do not describe historical facts, including but not limited to, statements regarding the promising nature of the ferumoxytol data presented in this press release, the opinion that these results support an attractive profile for ferumoxytol, the encouraging nature of these results and the timing of the planned submission of the NDA for ferumoxytol in the fourth quarter of calendar 2007 are forward-looking statements that involve risks and uncertainties that could cause actual results to differ materially from those discussed in such forward-looking statements. Such risks and uncertainties include the following: (1) the possibility that we may not be able to successfully complete the development of ferumoxytol, or may not be able to complete the development in a timely or cost-effective manner, due to deficiencies in the design or oversight by us of these trials, the failure of our trials to demonstrate that ferumoxytol is safe and efficacious, unexpected results from our clinical sites, inadequate performance by third-party service providers, or any other factor causing an increase in expenses, a delay and/or a negative effect on the results of the clinical studies for ferumoxytol; (2) uncertainties surrounding our ability to obtain regulatory approval for ferumoxytol from the FDA; (3) the possibility that the results of past ferumoxytol studies may not be replicated in future studies; (4) the fact that we have limited sales and marketing expertise; (5) the possibility that we may not be able to raise additional capital on terms and on a timeframe acceptable to us, if at all; (6) uncertainties relating to our patents and proprietary rights; and (7) other risks identified in our Securities and Exchange Commission filings. We caution readers not to place undue reliance on any forward-looking statements which speak only as of the date they are made. We disclaim any obligation to publicly update or revise any such statements to reflect any change in expectations or in events, conditions or circumstances on which any such statements may be based, or that may affect the likelihood that actual results will differ from those set forth in the forward-looking statements.

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