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                                                                  EXHIBIT 3.1(D)
                             ARTICLES OF AMENDMENT
                                       OF
                               NEORX CORPORATION
 
     Pursuant to RCW 23B.06.020, NeoRx Corporation, a Washington corporation,
hereby states that the Designation of Rights and Preferences of Series 2
Convertible Preferred Stock attached hereto as Exhibit A duly adopted by the
Board of Directors of the corporation on January 25, 1996.
 
     These Articles of Amendment are executed by said corporation by its duly
authorized officer.
 
     DATED: January 25, 1996
 
                                          NEORX CORPORATION
 
                                          By /s/  ROBERT M. LITTAUER
 
                                            ------------------------------------
                                                  Robert M. Littauer
                                                  Senior Vice President
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                                                                       EXHIBIT A
 
                    DESIGNATION OF RIGHTS AND PREFERENCES OF
                      SERIES 2 CONVERTIBLE PREFERRED STOCK
 
     A series of Preferred Stock is hereby designated as Series 2 Convertible
Preferred Stock which series shall consist of 50,000 shares, par value $.02 per
share (the "Series 2 Shares"), and which shall have the rights, preferences,
privileges and limitations as set forth below:
 
          (1) Dividends.  The holders of the Series 2 Shares shall be entitled
     to a dividend of eight percent (8%) per annum of the Stated Value (as
     defined below), on a cumulative basis with quarterly compounding (prorated
     for any portion of the applicable period during which the Series 2 Shares
     are outstanding). Dividends shall accrue from the date of issuance of the
     Series 2 Shares and shall be paid on each Series 2 Share at the time that
     such Series 2 Share is converted or redeemed. Dividends (including
     dividends payable to holders of Series 2 Shares as of the date such holder
     elects to convert the Series 2 Shares into Common Stock as provided in
     Section 2 below) may be paid at the Company's option in cash or Common
     Stock valued based on the Average Market Price (as defined below) of the
     Common Stock for the period of five (5) consecutive trading days ending on
     the trading day before the dividend payment dates or the date of conversion
     or redemption, as the case may be; provided, however, that in no event
     shall accrued dividends be paid in shares of Common Stock if, after giving
     effect to such distribution, the number of shares of Common Stock
     beneficially owned by such holder and all other holders whose holdings
     would be aggregated with such holder for purposes of calculating beneficial
     ownership in accordance with Sections 13(d) and 16 of the Securities
     Exchange Act of 1934, as amended, and the regulations thereunder ("Sections
     13(d) and 16"), including, without limitation, any person serving as an
     adviser to any holder (collectively, the "Related Persons"), would exceed
     four and nine-tenths percent (4.9%) of the outstanding shares of Common
     Stock (calculated in accordance with Sections 13(d) and 16); cash shall be
     paid in lieu of any shares which cannot be issued pursuant to this proviso.
     The Company shall not issue any fraction of a share of Common Stock in
     payment of a dividend, but shall pay cash therefor. The Company shall, so
     long as any of the Series 2 Shares are outstanding, reserve and keep
     available out of its authorized and unissued Common Stock, such number of
     shares of Common Stock as shall from time to time be sufficient to pay
     dividends hereunder. Every reference herein to the Common Stock of the
     Company (unless a different intention is expressed) shall be to the shares
     of the Common Stock of the Company, $.02 par value, as such stock exists
     immediately after the issuance of the Series 2 Shares provided for
     hereunder, or to stock into which such Common Stock may be changed from
     time to time thereafter.
 
          "Average Market Price" of any security for any period shall be
     computed as the arithmetic average of the closing bid prices for such
     security for each trading day in such period on the National Association of
     Securities Dealers Automated Quotation National Market System (the
     "Nasdaq-NMS"), or, if the Nasdaq-NMS is not the principal trading market
     for such security, on the principal trading market for such security, or,
     if market value cannot be calculated for such period on any of the
     foregoing bases, the Average Market Price shall be the average fair market
     value during such period as reasonably determined in good faith by the
     Board of Directors of the Company (all as appropriately adjusted for any
     stock dividend, stock split or other similar transaction during such period
     or between the end of such period and the date of conversion or dividend
     payment, as applicable).
 
          (2) Conversion of Series 2 Shares.  The holders of the Series 2 Shares
     shall have the right, at their option, to convert the Series 2 Shares into
     shares of Common Stock on the following terms and conditions:
 
             (a)(i) Each Series 2 share shall be convertible at any time after
        the date of issuance (or, if such Series 2 Share is called for
        redemption, at any time up to and including, but not after, the close of
        business on the fifth full business day prior to the date filed for such
        redemption, unless default shall be made by the Company in providing the
        funds for the payment of the redemption price), into fully paid and
        nonassessable shares (calculated to the nearest whole share) of Common
        Stock at the
 
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        conversion price (the "Conversion Price") in effect at the time of
        conversion determined as hereinafter provided; provided, however, that
        in no event shall any holder be entitled to convert Series 2 Shares if,
        after giving effect to such conversion, the number of shares of Common
        Stock beneficially owned by such holder and all Related Persons would
        exceed four and nine-tenths percent (4.9%) of the outstanding shares of
        Common Stock (calculated in accordance with Sections 13(d) and 16). Each
        Series 2 Share shall have a value of One Hundred Dollars ($100) (the
        "Stated Value") for the purpose of such conversion.
 
             (ii) Commencing on the later of (A) 180 days after the date of
        original issue of Series 2 Shares or (B) 90 days after the effective
        date of the Registration Statement (the "Registration Statement") filed
        by the Company pursuant to the Registration Rights Agreement between the
        Company and the original purchasers of the Series 2 Shares, the Company
        may at any time cause the automatic conversion of all outstanding Series
        2 Shares pursuant to written notice to the holders given not less than
        30 days and not more than 60 days prior to the date fixed in the notice.
        Any and all Series 2 Shares which have not been previously converted by
        the holders shall be automatically converted into shares of Common Stock
        as provided in Section (2)(a)(i) at the close of business on the date
        fixed in such notice, at the Conversion Price which is eighty-three
        percent (83%) (the "Conversion Percentage") of the Average Market Price
        for the Common Stock for the five (5) consecutive trading days ending
        one trading day prior to the date of automatic conversion; provided,
        however, that in no event shall the Conversion Price be an amount more
        than one hundred ten percent (110%) of the Average Market Price for the
        Common Stock for the five (5) consecutive trading days ending one
        trading day prior to the date of original issue of Series 2 Shares. The
        Conversion Price Floor described in Section (2)(b) shall not be
        applicable to an automatic conversion pursuant to this Section
        (2)(a)(ii).
 
          (b) The Conversion Price shall be eighty-three percent (83%) of the
     Average Market Price for the Common Stock for the five (5) consecutive
     trading days ending one trading day prior to the date the Conversion Notice
     (as defined below) is received by the Company, subject to adjustment as
     provided herein; provided, however, in no event shall the Conversion Price
     be an amount less than $4.41 per share of Common Stock (the "Conversion
     Price Floor") or more than one hundred ten percent (110%) of the Average
     Market Price for the Common Stock for the five (5) consecutive trading days
     ending one trading day prior to the issuance of the Series 2 Shares.
 
          (c) If the Company shall consolidate with or merge into any
     corporation or reclassify its outstanding shares of Common Stock (other
     than by way of subdivision or reduction of such shares) (each a "Major
     Transaction"), then each Series 2 Share shall thereafter be convertible
     into the number of shares of stock or securities (the "Resulting
     Securities") or property of the Company, or of the entity resulting from
     such consolidation or merger, to which a holder of the number of shares of
     Common Stock delivered upon conversion of such Series 2 Share would have
     been entitled upon such Major Transaction, had the holder of such Series 2
     Share exercised its right of conversion and had such Common Stock been
     issued and outstanding and had such holder been the holder of record of
     such Common Stock at the time of such Major Transaction, and the Company
     shall make lawful provision therefor as a part of such consolidation,
     merger or reclassification; provided, however, that during the period
     commencing on the date of original issue of Series 2 Shares and ending on
     the later of (A) 180 days after the date of original issue of Series 2
     Shares or (B) 90 days after the effective date of the Registration
     Statement, the Company shall not consummate a Major Transaction without the
     approval of the holders of a majority of the outstanding Series 2 Shares,
     unless (A) the Resulting Securities (or the securities into which the
     Resulting Securities are immediately convertible without the payment of
     additional consideration) are, at the date of the giving of the notice
     referred to in clause (B) below, listed or included for quotation on
     NASDAQ-NMS, the New York Stock Exchange or the American Stock Exchange (and
     are, at the date of the giving of such notice, reasonably expected to
     continue to be so listed or included for quotation for at least the six (6)
     month period subsequent to the closing of the Major Transaction); and (B)
     the Company gives such holder notice of such Major Transaction at least
     thirty (30) trading days prior to the closing thereof (excluding any
     trading days that sales cannot be made pursuant to the Registration
 
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     Statement for any reason); provided, further, that in any event the Company
     shall give the holders of the Series 2 Shares written notice of any Major
     Transaction not less than 30 days prior to its consummation.
 
          (d) The Company shall not issue any fraction of a share of Common
     Stock upon any conversion, but shall pay cash therefor at the Conversion
     Price then in effect multiplied by such fraction.
 
          (e) On presentation and surrender to the Company (or at any office or
     agency maintained for the transfer of the Series 2 Shares) of the
     certificates of Series 2 Shares so to be converted, duly endorsed in blank
     for transfer or accompanied by proper instruments of assignment or transfer
     in blank (a "Conversion Notice"), with signatures guaranteed, the holder of
     such Series 2 Shares shall be entitled, subject to the limitations herein
     contained, to receive in exchange therefor a certificate or certificates
     for fully paid and nonassessable shares, which certificates shall be
     delivered by the second trading day after the date of delivery of the
     Conversion Notice, and cash for fractional shares, of Common Stock on the
     foregoing basis. The Series 2 Shares shall be deemed to have been
     converted, and the person converting the same to have become the holder of
     record of Common Stock, for all purposes as of the date of delivery of the
     Conversion Notice.
 
          (f) The Company shall, so long as any of the Series 2 Shares are
     outstanding, reserve and keep available out of its authorized and unissued
     Common Stock, solely for the purpose of effecting the conversion of the
     Series 2 Shares, such number of shares of Common Stock as shall from time
     to time be sufficient to effect the conversion of all of the Series 2
     Shares then outstanding.
 
          (g) The Company shall pay any and all taxes which may be imposed upon
     it with respect to the issuance and delivery of Common Stock upon the
     conversion of the Series 2 Shares as herein provided. The Company shall not
     be required in any event to pay any transfer or other taxes by reason of
     the issuance of such Common Stock in names other than those in which the
     Series 2 Shares surrendered for conversion are registered on the Company's
     records, and no such conversion or issuance of Common Stock shall be made
     unless and until the person requesting such issuance has paid to the
     Company the amount of any such tax, or has established to the satisfaction
     of the Company and its transfer agent, if any, that such tax has been paid.
 
     (3) Voting Rights.  Holders of Series 2 Shares shall have no voting rights,
except as required by law.
 
     (4) Redemption.  The Company may, at any time subsequent to ninety (90)
days after the issuance of the Series 2 Shares, redeem the whole or any part of
the Series 2 Shares then outstanding at a redemption price of One Hundred Twenty
Dollars and Fifty Cents ($120.50) per Series 2 Share, plus in each case a sum
equal to all accrued and unpaid dividends thereon through the date fixed for
redemption, in accordance with the following redemption procedures:
 
          (a) In case of redemption of only part of the Series 2 Shares at any
     time outstanding, the Company shall designate the amount of Series 2 Shares
     so to be redeemed and shall redeem such Series 2 Shares on a pro rata
     basis. Subject to the limitations and provisions herein contained, the
     Board of Directors shall have the power and authority to prescribe the
     terms and conditions upon which the Series 2 Shares shall be redeemed from
     time to time.
 
          (b) Notice of every redemption shall be given by mail to every holder
     of record of any Series 2 Shares then to be redeemed, at least thirty (30),
     but no more than ninety (90), days prior to the date fixed as the date for
     the redemption thereof, at the respective addresses of such holders as the
     same shall appear on the stock transfer books of the Company. The notice
     shall state that the Series 2 Shares shall be redeemed by the Company at
     the redemption price specified above, upon the surrender for cancellation,
     at the time and place designated in such notice, of the certificates
     representing the Series 2 Shares to be redeemed, properly endorsed in blank
     for transfer, or accompanied by proper instruments of assignment and
     transfer in blank, with signatures guaranteed, and bearing all necessary
     transfer tax stamps thereto affixed and cancelled. On and after the date
     specified in the notice described above, each holder of Series 2 Shares
     called for redemption shall be entitled to receive therefor the specified
     redemption price upon presentation and surrender at the place designated in
     such notice of the certificates for Series 2 Shares called for redemption,
     properly endorsed in blank for transfer or accompanied by
 
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     proper instruments of assignment or transfer in blank, with signatures
     guaranteed, and bearing all necessary transfer tax stamps thereto affixed
     and cancelled.
 
          (c) If the Company shall give notice of redemption as aforesaid (and
     unless the Company shall fail to pay the redemption price of the Series 2
     Shares presented for redemption in accordance with such notice), all Series
     2 Shares called for redemption shall be deemed to have been redeemed on the
     date specified in such notice, whether or not the certificates for such
     Series 2 Shares shall be surrendered for redemption, and such Series 2
     Shares so called for redemption shall from and after such date cease to
     represent any interest whatsoever in the Company or its property, and the
     holders thereof shall have no rights other than the right to receive such
     redemption price without any interest thereof from and after such date.
 
     (5) Liquidation, Dissolution, Winding Up.  In the event of any voluntary or
involuntary liquidation, dissolution or winding up of the Company, the holders
of the Series 2 Shares shall be entitled to receive in cash out of the assets of
the Company, whether from capital or from earnings, available for distribution
to its stockholders (the "Series 2 Funds"), before any amount shall be paid to
the holders of the Common Stock, an amount equal to the Stated Value per Series
2 Share plus any accrued and unpaid dividends, provided that, if the Series 2
Funds are insufficient to pay the full amount due to the holders of Series 2
Shares and holders of shares of other classes or series of preferred stock of
the Company that are of equal rank with the Series 2 Shares as to payments of
Series 2 Funds (the "Pari Passu Shares"), then each holder of Series 2 Shares
and Pari Passu Shares shall receive a percentage of the Series 2 Funds equal to
the full amount of Series 2 Funds payable to such holder as a percentage of the
full amount of Series 2 Funds payable to all holders of Series 2 Shares and Pari
Passu Shares. The purchase or redemption by the Company of stock of any class,
in any manner permitted by law, shall not, for the purposes hereof, be regarded
as a liquidation, dissolution or winding up of the Company. Neither the
consolidation nor merger of the Company with or into any other corporation or
corporations, nor the sale or transfer by the Company of less than substantially
all of its assets, shall, for the purposes hereof, be deemed to be a
liquidation, dissolution or winding up of the Company. No holder of Series 2
Shares shall be entitled to receive any amounts with respect thereto upon any
liquidation, dissolution or winding up of the Company other than the amounts
provided for herein.
 
     (6) Series 2 Rank.  All shares of Common Stock shall be of junior rank to
all Series 2 Shares in respect to the preferences as to dividends, distributions
and payments upon the liquidation, dissolution or winding up of the Company. The
rights of the shares of Common Stock shall be subject to the preferences and
relative rights of the Series 2 Shares. The Series 2 Shares shall rank junior to
the Company's Convertible Exchangeable Preferred Stock, Series 1 in respect of
dividends and distributions and payments upon the liquidation, dissolution or
winding up of the Company. The Company may authorize and issue additional or
other preferred stock which is of equal rank with the Series 2 Shares in respect
of the preferences as to dividends and distributions and payments upon the
liquidation, dissolution or winding up of the Company. In the event of the
merger or consolidation of the Company with or into another corporation, the
Series 2 Shares shall maintain their relative powers, designations and
preferences provided for herein.
 
     (7) Vote to Change the Terms of Series 2 Shares.  The affirmative vote at a
meeting duly called for such purpose of the written consent without a meeting of
the holders of the not less than two-thirds ( 2/3) of the then outstanding
Series 2 Shares shall be required to amend, alter, change or repeal any of the
powers, designations, preferences and rights of the Series 2 Shares.
 
     (8) Amendments Upon Conversion or Redemption of Outstanding Series 2
Shares.  When, as a result of the conversion or redemption of the Series 2
Shares, no Series 2 Shares remain outstanding, the Board of Directors may, at
its discretion and without a vote of the shareholders of the Company, withdraw
this Designation in its entirety by providing for the filing of the applicable
amendment or restatement of the Company's Restated Articles of Incorporation,
and the Series 2 Shares designated hereby shall thereby return to the status of
authorized but unissued and undesignated shares of Preferred Stock of the
Company.
 
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