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                                                                     EXHIBIT 4.1

               SECOND AGREEMENT AND AMENDMENT TO RIGHTS AGREEMENT

                  This SECOND AGREEMENT AND AMENDMENT TO RIGHTS AGREEMENT (this
"Amendment") is being entered into as of June 20, 2003, between Biogen, Inc., a
Massachusetts corporation (the "Company"), and EquiServe Trust Company, N.A., as
rights agent (the "Rights Agent").

                  WHEREAS, the Company and the Rights Agent are parties to a
Rights Agreement, dated as of May 8, 1999, between the Company and the Rights
Agent, as previously amended by an Agreement and Amendment to Rights Agreement,
dated as of May 31, 2002, between State Street Bank and Trust Company, the
Company and EquiServe Trust Company, N.A. (as so amended, the "Rights
Agreement"); and

                  WHEREAS, it is proposed that the Company enter into an
Agreement and Plan of Merger (as it may be amended from time to time, the
"Merger Agreement") by and among IDEC Pharmaceuticals Corporation, a Delaware
corporation ("IDEC"), Bridges Merger Corporation, a Massachusetts corporation
and wholly owned subsidiary of IDEC ("Merger Sub"), and the Company, pursuant to
which Merger Sub will merge with and into the Company; and

                  WHEREAS, pursuant to Section 27 of the Rights Agreement, the
Company and the Rights Agent may supplement or amend the Rights Agreement in
accordance with the provisions of such Section 27. The Company now desires to
amend the Rights Agreement as set forth in this Amendment and deems such
amendments to be necessary and desirable. Capitalized terms used but not defined
herein shall have the meanings ascribed to such terms in the Rights Agreement.

                  NOW THEREFORE, in consideration of the premises and the mutual
agreements herein set forth, the parties hereby agree as follows:

                  1. AMENDMENT OF SECTION 1(a). Section 1(a) of the Rights
Agreement is hereby replaced in its entirety to read as follows:

                           "(a) 'ACQUIRING PERSON' shall mean any Person (as
                  such term is hereinafter defined) who or which, together with
                  all Affiliates and Associates (as such terms are hereinafter
                  defined) of such Person, shall be the Beneficial Owner (as
                  such term is hereinafter defined) of 10% or more of the Common
                  Shares of the Company then outstanding. Notwithstanding the
                  foregoing, (A) the term Acquiring Person shall not include (i)
                  the Company, (ii) any Subsidiary (as such term is hereinafter
                  defined) of the Company or (iii) any employee

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                  benefit plan of the Company or any Subsidiary of the Company
                  or any entity holding Common Shares of the Company for or
                  pursuant to the terms of any such employee benefit plan and
                  (B) no Person shall become an 'Acquiring Person' (x) as the
                  result of an acquisition of Common Shares of the Company by
                  the Company which, by reducing the number of shares
                  outstanding, increases the proportionate number of shares
                  beneficially owned by such Person to 10% or more of the Common
                  Shares of the Company then outstanding; provided, however,
                  that, if a Person shall become the Beneficial Owner of 10% or
                  more of the Common Shares of the Company then outstanding by
                  reason of share acquisitions by the Company and shall, after
                  such share acquisitions by the Company, become the Beneficial
                  Owner of any additional Common Shares of the Company, then
                  such Person shall be deemed to be an 'Acquiring Person,' (y)
                  if such Person, prior to June 20, 2003 became the Beneficial
                  Owner of 10% or more of the Common Shares of the Company then
                  outstanding, unless such Person becomes the Beneficial Owner
                  of (1) 1% (or any percentage greater than 1%) of the Common
                  Shares of the Company then outstanding in excess of (2) the
                  percentage of Common Shares of the Company then outstanding
                  Beneficially Owned by such Person on (aa) June 20, 2003 or
                  (bb) thereafter, whichever such percentage is less; provided,
                  however, that the sum of the percentage referred to in clause
                  (y)(2) immediately above, plus 1%, shall not be less than 10%
                  or (z) if such Person is the Beneficial Owner of less than 15%
                  of the Common Shares of the Company then outstanding and has
                  reported or is required to report such Person's Beneficial
                  Ownership on Schedule 13G under the Exchange Act (or any
                  comparable or successor report), or on Schedule 13D under the
                  Exchange Act (or any comparable or successor report) which
                  Schedule 13D does not state any intention to or reserve the
                  right to control or influence the management or policies of
                  the Company or engage in any of the actions specified in Item
                  4 (or any comparable or successor item) of such schedule
                  (other than the disposition of the Common Shares of the
                  Company) and, within 10 Business Days of being requested by
                  the Company to advise it regarding the same, certifies to the
                  Company that such Person acquired Common Shares of the Company
                  in excess of 9.99% inadvertently or without knowledge of the
                  terms of the Rights and who, together with all of such
                  Person's Affiliates and Associates, thereafter does not
                  acquire additional Common Shares of the Company while the
                  Beneficial Owner of 10% or more of the Common Shares of the
                  Company then outstanding; provided,

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                  however, that if the Person requested to so certify fails to
                  do so within 10 Business Days, then such Person shall become
                  an Acquiring Person immediately after such 10-Business-Day
                  period. Notwithstanding anything in this Agreement to the
                  contrary, neither IDEC nor any of its existing or future
                  Affiliates or Associates shall be deemed to be an Acquiring
                  Person solely by virtue of (i) the execution or delivery of
                  the Merger Agreement, (ii) the acquisition of Common Shares of
                  the Company (including the conversion of shares of common
                  stock of Merger Sub into Common Shares or other common stock
                  of the Company) pursuant to the Merger Agreement or (iii) the
                  consummation of the other transactions contemplated by the
                  Merger Agreement."

                  2. AMENDMENT OF SECTION 1(o). Section 1(o) of the Rights
Agreement is hereby replaced in its entirety to read as follows:

                           "(s) 'SHARES ACQUISITION DATE' shall mean the earlier
                  of the first date of (i) the public announcement by the
                  Company or an Acquiring Person that an Acquiring Person has
                  become such or (ii) the public disclosure of facts by the
                  Company or an Acquiring Person indicating that an Acquiring
                  Person has become such."

                  3. AMENDMENT OF SECTION 1. Section 1 of the Rights Agreement
is hereby amended to add the following subparagraphs at the end thereof:

                           (r) "'AMENDMENT NO. 2' shall mean the Second
                  Agreement and Amendment to Rights Agreement, dated as of June
                  20, 2003, by and between the Company and the Rights Agent."

                           (s) "'AMENDMENT NO. 2 EFFECTIVE TIME' shall mean the
                  date and time the Amendment No. 2 is fully executed and
                  delivered."

                           (t) "'IDEC' shall mean IDEC Pharmaceuticals
                  Corporation, a Delaware corporation."

                           (u) "'MERGER' shall have the meaning set forth in the
                  Merger Agreement."

                           (v) "'MERGER AGREEMENT' shall have the meaning set
                  forth in Section 35 hereof."

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                           (w) "'MERGER SUB' shall have the meaning set forth in
                  Section 35 hereof."

                  4. AMENDMENT OF SECTION 3(a). Section 3(a) of the Rights
Agreement is hereby amended to add the following sentence at the end thereof:

                  "Notwithstanding anything in this Agreement to the contrary, a
                  Distribution Date shall not be deemed to have occurred solely
                  by virtue of (i) the execution or delivery of the Merger
                  Agreement, (ii) the acquisition of Common Shares of the
                  Company (including the conversion of shares of common stock of
                  Merger Sub into Common Shares or other common stock of the
                  Company) pursuant to the Merger Agreement or (iii) the
                  consummation of the other transactions contemplated by the
                  Merger Agreement."

                  5. AMENDMENT OF SECTION 7(a). Section 7(a) of the Rights
Agreement is hereby amended to add the following sentence at the end thereof:

                  "Notwithstanding anything in this Agreement to the contrary,
                  none of (i) the execution or delivery of the Merger Agreement,
                  (ii) the acquisition of Common Shares of the Company
                  (including the conversion of shares of common stock of Merger
                  Sub into Common Shares or other common stock of the Company)
                  pursuant to the Merger Agreement or (iii) the consummation of
                  the other transactions contemplated by the Merger Agreement
                  shall be deemed to be events that cause the Rights to become
                  exercisable pursuant to the provisions of this Section 7 or
                  otherwise."

                  6. AMENDMENT OF SECTION 11. Section 11 of the Rights Agreement
is hereby amended to add the following sentence after the first sentence of said
Section:

                  "Notwithstanding anything in this Agreement to the contrary,
                  none of (i) the execution or delivery of the Merger Agreement,
                  (ii) the acquisition of Common Shares of the Company
                  (including the conversion of shares of common stock of Merger
                  Sub into Common Shares or other common stock of the Company)
                  pursuant to the Merger Agreement or (iii) the consummation of
                  the other transactions

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                  contemplated by the Merger Agreement shall be deemed to be
                  events of the type described in this Section 11 or to cause
                  the Rights to be adjusted or to become exercisable in
                  accordance with this Section 11."

                  7. AMENDMENT OF SECTION 13. Section 13 of the Rights Agreement
is hereby amended to add the following subparagraph at the end thereof:

                  "(e) Notwithstanding anything in this Agreement to the
                  contrary, none of (i) the execution or delivery of the Merger
                  Agreement, (ii) the acquisition of Common Shares of the
                  Company (including the conversion of shares of common stock of
                  Merger Sub into Common Shares or other common stock of the
                  Company) pursuant to the Merger Agreement or (iii) the
                  consummation of the other transactions contemplated by the
                  Merger Agreement shall be deemed to be events of the type
                  described in this Section 13 or to cause the Rights to be
                  adjusted or to become exercisable in accordance with this
                  Section 13 or otherwise to be subject to any restrictions
                  contained in this Section 13."

                  8. AMENDMENT OF SECTION 21. Section 21 of the Rights Agreement
is hereby amended to add the following sentence after the first sentence of said
Section:

                  "In the event the transfer agency relationship in effect
                  between the Company and the Rights Agent terminates, the
                  Rights Agent will be deemed to resign automatically on the
                  effective date of such termination; and any required notice
                  will be sent by the Company."

                  9. AMENDMENT OF SECTION 23(b). Section 23(b) of the Rights
Agreement is hereby replaced in its entirety to read as follows:

                  "(b) The Board of Directors of the Company may, at its option,
                  at any time prior to the earlier of (i) the Close of Business
                  on the tenth Business Day following the Shares Acquisition
                  Date; or (ii) the Final Expiration Date, redeem all but not
                  less than all of the then outstanding Rights at a redemption
                  price of $.001 per Right, appropriately adjusted to reflect
                  any stock split, stock dividend or similar transaction
                  occurring after the date hereof (such redemption price being
                  hereinafter referred to as the "Redemption Price"). The
                  redemption of the Rights by the Board of Directors may be made

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                  effective at such time, on such basis and subject to such
                  conditions as the Board of Directors in its sole discretion
                  may establish."

                  10. ADDITION OF SECTION 35. The Rights Agreement is hereby
amended to add the following new Section 35:

                  "SECTION 35. MERGER WITH BRIDGES MERGER CORPORATION

                  The Company, IDEC and Bridges Merger Corporation, a
                  Massachusetts corporation and wholly owned subsidiary of IDEC
                  ("Merger Sub"), intend to enter into an Agreement and Plan of
                  Merger, of even date of the Amendment No. 2, to be entered
                  into following the Amendment No. 2 Effective Time (as it may
                  be amended from time to time, the "Merger Agreement"),
                  pursuant to which Merger Sub shall merge with and into the
                  Company, with the Company continuing as the surviving
                  corporation. Notwithstanding anything in this Agreement to the
                  contrary, if the Merger Agreement shall be terminated for any
                  reason, then, effective as of the time of such termination,
                  the following provisions which were added to this Agreement by
                  the Amendment No. 2 shall be deemed repealed and deleted
                  without any further action on the part of the Company or the
                  Rights Agent: (1) the last sentence of Section 1(a) hereof,
                  (2) subsections (r) through (w) of Section 1 hereof, (3) the
                  last sentence of Section 3(a) hereof, (4) the last sentence of
                  Section 7(a) hereof, (5) the second sentence of Section 11
                  hereof and (6) Section 13(e) hereof."

                  11. ADDITION OF SECTION 36. The Rights Agreement is hereby
amended to add the following new Section 36:

                  "SECTION 36. FORCE MAJEURE

                  Notwithstanding anything to the contrary contained herein, the
                  Rights Agent shall not be liable for any delays or failures in
                  performance resulting from acts beyond its reasonable control
                  including, without limitation, acts of God, terrorist acts,
                  shortage of supply, breakdowns or malfunctions, interruptions
                  or malfunction of computer facilities, or loss of data due to
                  power failures or mechanical difficulties with information
                  storage or retrieval systems, labor difficulties, war, or

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                  civil unrest, to the extent such acts or events are actually
                  beyond the Rights Agent's reasonable control."

                  12. EFFECTIVENESS. This Amendment shall be deemed effective as
of the date first set forth above, as if executed and delivered on such date.
Except as amended hereby, the Rights Agreement shall remain in full force and
effect and shall be otherwise unaffected hereby.

                  13. MISCELLANEOUS. This Amendment shall be deemed to be a
contract made under the laws of the Commonwealth of Massachusetts and for all
purposes shall be governed by and construed in accordance with the laws of the
Commonwealth of Massachusetts applicable to contracts to be made and performed
entirely within the Commonwealth of Massachusetts without giving effect to the
principles of conflict of laws thereof that would require the application of any
other law. This Amendment may be executed in separate counterparts, each of such
counterparts shall for all purposes be deemed to be an original, and all such
counterparts shall together constitute but one and the same instrument. If any
provision, covenant or restriction of this Amendment is held by a court of
competent jurisdiction or other authority to be invalid, illegal or
unenforceable, the remainder of the terms, provisions, covenants and
restrictions of this Amendment shall remain in full force and effect and shall
in no way be affected, impaired or invalidated.

                           [Signature Page To Follow]

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                  IN WITNESS WHEREOF, this Second Agreement and Amendment to
Rights Agreement is executed under seal as of the date first set forth above.

                                  BIOGEN, INC.

                                  By:   /s/  Anne Marie Cook
                                      ------------------------------------------
                                      Name:  Anne Marie Cook
                                      Title: Vice President, Chief Corporate
                                             Counsel

                                  EQUISERVE TRUST COMPANY, N.A., as Rights Agent

                                  By:   /s/  Dennis V. Moccia
                                      ------------------------------------------
                                      Name:  Dennis V. Moccia
                                      Title: Managing Director<PAGE>

                      CERTIFICATE OF DESIGNATION OF SERIES

                   AND DETERMINATION OF RIGHTS AND PREFERENCES

                                       OF

                      CONVERTIBLE PREFERRED STOCK, SERIES B

                                       OF

                              VALESC HOLDINGS INC.

         Valesc Holdings Inc., a Delaware corporation (the "Company"), acting
pursuant to ss.151 of the General Corporation Law of Delaware, does hereby
submit the following Certificate of Designation of Series and Determination of
Rights and Preferences of its Convertible Preferred Stock, Series B.

         FIRST:  The name of the Company is Valesc Holdings Inc.

         SECOND: By unanimous consent of the Board of Directors of the Company
dated June 17, 2003, the following resolutions were duly adopted:

         WHEREAS the Certificate of Incorporation of the Company authorizes
Preferred Stock consisting of up to 20,000,000 shares, par value $.0001 per
share, issuable from time to time in one or more series; and

         WHEREAS the Board of Directors of the Company is authorized, subject to
limitations prescribed by law and by the provisions of Article FOURTH of the
Company's Certificate of Incorporation, as amended, to establish and fix the
number of shares to be included in any series of Preferred Stock and the
designation, rights, preferences, powers, restrictions and limitations of the
shares of such series; and

         WHEREAS it is the desire of the Board of Directors to establish and fix
the number of shares to be included in a new series of Preferred Stock and the
designation, rights, preferences and limitations of the shares of such new
series;

         NOW, THEREFORE, BE IT RESOLVED that pursuant to Article FOURTH of the
Company's Certificate of Incorporation, as amended, there is hereby established
a new series of 100,000 shares of convertible Preferred Stock of the Company
(the "Series B Preferred Stock") to have the designation, rights, preferences,
powers, restrictions and limitations set forth in a supplement of Article FOURTH
as follows:

         1. Dividends.

         The holders of the Series B Preferred Stock shall be entitled to such
dividends paid and distributions made to the holders of Common Stock to the same
extent as if the holders of the Series B Preferred Stock had converted their
shares of Series B Preferred Stock pursuant to the

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provisions of Section 3 hereof and had been issued such Common Stock on the day
before the record date for said dividend or distribution, provided that the
holders of the Series B Preferred Stock will not receive dividends or
distributions which are payable in Common Stock. Cash payments under the
preceding sentence, if any, shall be made concurrently with cash dividends and
cash distributions to the holders of Common Stock.

         2. Voting.

         Except as otherwise provided by applicable law, the holders of
outstanding shares of the Series B Preferred Stock will not have any voting
rights.

         3. Optional Conversion.

         (a) Each holder of Series B Preferred Stock may, at any time and from
time to time beginning three months after the issue date, convert some or all of
such holder's shares of Series B Preferred Stock into a number of shares of
Common Stock determined by multiplying the number of shares to be converted by
$100 and then dividing the product by the Market Price (the "Conversion Ratio").
Each conversion shall be for no fewer than 1,000 shares of Series B Preferred
Stock, unless the holder is converting all shares then held by him or her of
record. "Market Price" shall mean the average closing price of the Common Stock
(in U.S. dollars) over the 60 trading days immediately preceding the date the
shares are submitted to the Company for conversion, as reported on the NASD OTC
Bulletin Board or (if applicable) on the primary national securities exchange
over which the Common Stock is regularly traded in the United States. If the
Common Stock is not listed on the NASD OTC Bulletin Board or a national
securities exchange, then Market Price shall be determined by multiplying the
Company's net income for the prior year by 6 and then dividing the product by
the number of fully diluted common shares outstanding at the time of conversion.

         (b) In order for a holder of Series B Preferred Stock to effect a
conversion of Series B Preferred Stock into shares of Common Stock such holder
shall (i) fax a copy of the fully executed notice of conversion in the form of
Exhibit A attached hereto ("Notice of Conversion") to the Company, and (ii)
surrender or cause to be surrendered the certificates representing the Series B
Preferred Stock being converted accompanied by duly executed stock powers and
the original executed version of the Notice of Conversion as soon as practicable
thereafter.

         (c) Within five business days after the Company's receipt of a Notice
of Conversion, the Company shall require the Company's transfer agent to
promptly issue and deliver to the holder of Series B Preferred Stock who
provided the Notice of Conversion (i) that number of shares of Common Stock
issuable upon conversion of such shares of Series B Preferred Stock being
converted, and (ii) a certificate representing the number of shares of Series B
Preferred Stock not being converted, if any.

         (d) The Company shall at all times reserve and keep available for
issuance upon the conversion of the Series B Preferred Stock, free from any
preemptive rights, such number of its authorized but unissued shares of Common
Stock as will from time to time be necessary to permit the conversion of all
outstanding shares of Series B Preferred Stock into shares of

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Common Stock, and shall take all action required to increase the authorized
number of shares of Common Stock if necessary to permit the conversion of all
outstanding shares of Series B Preferred Stock. In no event will the amount of
Common Stock reserved for conversion of the Series B Preferred Stock be less
than 2,000,000 shares.

         (e) The issuance of certificates for shares of Common Stock upon
conversion of the Series B Preferred Stock shall be made without charge to the
holders thereof for any issuance tax in respect thereof, provided that the
Company shall not be required to pay any tax which may be payable in respect of
any transfer involved in the issuance and delivery of any certificate in a name
other than that of the holder of the Series B Preferred Stock which is being
converted.

         (f) The Company will at no time close its transfer books against the
transfer of any Series B Preferred Stock, or of any shares of Common Stock
issued or issuable upon the conversion of any shares of Series B Preferred Stock
in any manner which interferes with the timely conversion of such Series B
Preferred Stock, except as may otherwise be required to comply with applicable
securities laws.

         (g) No fractional shares of Common Stock or scrip shall be issued upon
conversion of shares of Series B Preferred Stock. If more than one certificate
for Series B Preferred Stock shall be surrendered for conversion at any one time
by the same holder, the number of full shares of Common Stock issuable upon
conversion thereof shall be computed on the basis of the aggregate number of
shares of Series B Preferred Stock to be converted.

         4. Mandatory Conversion.

         Each share of Series B Preferred Stock outstanding on the fifth
anniversary of the date of original issuance of any such shares shall
automatically be converted into shares of Common Stock in accordance with the
terms of Section 3 utilizing the Conversion Ratio then in effect.

         5. Amendment.

         This Certificate of Designation constitutes an agreement between the
Company and the holders of the Series B Preferred Stock. It may be amended by
vote of the Board of Directors of the Company and the holders of not less than
two-thirds of the outstanding shares of Series B Preferred Stock.

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         IN WITNESS WHEREOF, the Company has caused this Certificate to be
executed by its President and attested to by its Secretary this 17th day of
June, 2003

                                       By:
                                          --------------------------------------
                                                  Samuel Cohen, President

ATTEST:

--------------------------------------
Secretary

[Seal]

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                                                                       EXHIBIT A

                              NOTICE OF CONVERSION

         As of the date of receipt by the Company, the undersigned hereby
irrevocably elects to convert (the "Conversion") shares of the Series B
Convertible Preferred Stock (the "Series B Preferred Stock") into shares of
common stock, $.0001 par value per share ("Common Stock") of Valesc Holdings
Inc. (the "Corporation") according to the conditions of the Certificate of
Designation of Series and Determination of Rights and Preferences of Convertible
Preferred Stock, Series B of the Corporation.

         The undersigned covenants that all offers and sales by the undersigned
of the Common Stock or other securities issuable to the undersigned upon
conversion of this Series B Preferred Stock shall be made pursuant to
registration of such Common Stock under the Securities Act of 1933, as amended
(the "Act"), or pursuant to an exemption from registration under the Act with a
restrictive legend.

         Date of Conversion:                            _____________

         Number of Preferred Shares to be Converted:    _____________

         Applicable Market Price:                       _____________

         Number of Shares of Common Stock to be Issued: _____________

         In the event of partial exercise, please reissue an appropriate Series
B Preferred Stock certificate(s) for the shares of Series B Preferred Stock that
shall not have been converted.

-------------------------------
Signature

Printed Name:
             ------------------
Address:

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