UNITED STATES
                   SECURITIES AND EXCHANGE COMMISSION        OMB APPROVAL
                          WASHINGTON, D.C. 20549       -------------------------
                                                       OMB Number: 3235-0145
                                                       Expires: October 31, 1997
                                                       Estimated average burden
                                                       hours per response..14.90


                              SCHEDULE 13D

                  UNDER THE SECURITIES EXCHANGE ACT OF 1934
                              (AMENDMENT NO. 1)*

                       IDEC Pharmaceuticals Corporation
                               (Name of Issuer)

                                 Common Stock
                         (Title of Class Securities)

                                 449370 10 5
                                (CUSIP Number)


                             Dr. Robert E. Curry
                            ML/MS Associates, L.P.
                             3000 Sand Hill Road
                            Menlo Park, CA  94025
 (Name, Address and Telephone Number of Person Authorized to Receive Notices
and Communications)

                                 May 1, 1997
            (Date of Event which Requires Filing of this Statement)





*The remainder  of  this cover  page  shall be  filled  out for  a  reporting
person's initial filing  on this form  with respect to  the subject class  of
securities, and  for any  subsequent amendment  containing information  which
would alter the disclosures provided in a prior cover page.

The information  required in the  remainder of this  cover page shall  not be
deemed to be "filed" for the purpose of Section 18 of the Securities Exchange
Act of 1934 ("Act")  or otherwise subject to the liabilities  of that section
of the Act but shall be subject to all other  provisions of the Act (however,
see the Notes).




                                 SCHEDULE 13D

CUSIP NO.  449370 10 5                         PAGE   2    OF   21   PAGES
          ------------                             -------   --------


<TABLE>
<CAPTION>
<S>    <C>                                                               <C>
1      NAME OF REPORTING PERSON
       S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON  
            ML/MS Associates, L.P.
2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                 (a) / /
                                                                         (b) /x/
3      SEC USE ONLY
4      SOURCE OF FUND*

            WC
5      CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED
       PURSUANT TO ITEMS 2(d) or 2(e)

            Not Applicable
6      CITIZENSHIP OR PLACE OF ORGANIZATION

            California

</TABLE>




<TABLE>
<CAPTION>
<S>               <C>    <C>
    NUMBER OF     7      SOLE VOTING POWER
      SHARES                  0
   BENEFICIALLY   8      SHARED VOTING POWER
     OWNED BY
                              372,048 shares of common stock
      EACH        9      SOLE DISPOSITIVE POWER
    REPORTING
                              0
      PERSON      10     SHARED DISPOSITIVE POWER
       WITH 
                              372,048 shares of common stock

</TABLE>



<TABLE>
<CAPTION>
<S>    <C>                                                                             <C>
11     AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
            372,048 shares of common stock
12     CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES*          / /

            Not Applicable
13     PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

            2.02%
14     TYPE OF REPORTING PERSON*

            PN

</TABLE>


                   *SEE INSTRUCTION BEFORE FILLING OUT!
         INCLUDE BOTH SIDES OF THE COVER PAGE, RESPONSES TO ITEMS 1-7
     (INCLUDING EXHIBITS) OF THE SCHEDULE, AND THE SIGNATURE ATTESTATION


                                 SCHEDULE 13D
CUSIP NO.  449370 10 5                             PAGE   3    OF   21   PAGES
         --------------                                 -------   --------


<TABLE>
<CAPTION>
<S>    <C>                                                               <C>
1      NAME OF REPORTING PERSON
       S.S. or I.R.S  IDENTIFICATION NO. OF ABOVE PERSON
            MLMS Cancer Research, Inc.
2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                 (a) / /
                                                                         (b) /x/
3      SEC USE ONLY
4      SOURCE OF FUND*

            AF
5      CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED
       PURSUANT TO ITEMS 2(d) or 2(e)

            Not Applicable
6      CITIZENSHIP OR PLACE OF ORGANIZATION

            California

</TABLE>



<TABLE>
<CAPTION>
<S>               <C>    <C>
    NUMBER OF     7      SOLE VOTING POWER
      SHARES                  0
   BENEFICIALLY   8      SHARED VOTING POWER
     OWNED BY
                              372,048 shares of common stock
      EACH        9      SOLE DISPOSITIVE POWER
    REPORTING   
                              0
      PERSON      10     SHARED DISPOSITIVE POWER
       WITH 
                              372,048 shares of common stock

</TABLE>



<TABLE>
<CAPTION>
<S>    <C>                                                                             <C>
11     AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
            372,048 shares of common stock
12     CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES*          / /

            Not Applicable
13     PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

            2.02%
14     TYPE OF REPORTING PERSON*

            CO

</TABLE>


                     *SEE INSTRUCTION BEFORE FILLING OUT!
         INCLUDE BOTH SIDES OF THE COVER PAGE, RESPONSES TO ITEMS 1-7
     (INCLUDING EXHIBITS) OF THE SCHEDULE, AND THE SIGNATURE ATTESTATION


                                 SCHEDULE 13D
CUSIP NO.  449370 10 5                           PAGE   4    OF   21   PAGES
         --------------                              -------   --------


<TABLE>
<CAPTION>
<S>    <C>                                                               <C>
1      NAME OF REPORTING PERSON
       S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
            ML Venture Partners II, L.P.
2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                 (a) / /
                                                                         (b) /x/
3      SEC USE ONLY
4      SOURCE OF FUND*

            AF
5      CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED
       PURSUANT TO ITEMS 2(d) or 2(e)

            Not Applicable
6      CITIZENSHIP OR PLACE OF ORGANIZATION

            Delaware

</TABLE>



<TABLE>
<CAPTION>
<S>               <C>    <C>
    NUMBER OF     7      SOLE VOTING POWER
      SHARES                  150,264
   BENEFICIALLY   8      SHARED VOTING POWER
     OWNED BY
                              129,409 shares of common stock
      EACH        9      SOLE DISPOSITIVE POWER
    REPORTING   
                              150,264
      PERSON      10     SHARED DISPOSITIVE POWER
       WITH 
                              129,409 shares of common stock

</TABLE>



<TABLE>
<CAPTION>
<S>    <C>                                                                             <C>
11     AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
            279,673 shares of common stock
12     CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES*          / /

            Not Applicable
13     PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

            1.52%
14     TYPE OF REPORTING PERSON*

            PN

</TABLE>



                     *SEE INSTRUCTION BEFORE FILLING OUT!
         INCLUDE BOTH SIDES OF THE COVER PAGE, RESPONSES TO ITEMS 1-7
     (INCLUDING EXHIBITS) OF THE SCHEDULE, AND THE SIGNATURE ATTESTATION


                                 SCHEDULE 13D

CUSIP NO.  449370 10 5                              PAGE   5    OF   21   PAGES
          --------------                                -------   --------


<TABLE>
<CAPTION>
<S>    <C>                                                               <C>
1      NAME OF REPORTING PERSON
       S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
            MLVPII Co., L.P.
2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                 (a) / /
                                                                         (b) /x/
3      SEC USE ONLY
4      SOURCE OF FUND*

            AF
5      CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED
       PURSUANT TO ITEMS 2(d) or 2(e)

            Not Applicable
6      CITIZENSHIP OR PLACE OF ORGANIZATION

            New York

</TABLE>



<TABLE>
<CAPTION>
<S>               <C>    <C>
    NUMBER OF     7      SOLE VOTING POWER
      SHARES                  150,264
   BENEFICIALLY   8      SHARED VOTING POWER
     OWNED BY
                              129,409 shares of common stock
      EACH        9      SOLE DISPOSITIVE POWER
    REPORTING   
                              150,264
      PERSON      10     SHARED DISPOSITIVE POWER
       WITH
                              129,409 shares of common stock

</TABLE>



<TABLE>
<CAPTION>
<S>    <C>                                                                             <C>
11     AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
            279,673 shares of common stock
12     CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES*          / /

            Not Applicable
13     PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

            1.52%
14     TYPE OF REPORTING PERSON*

            PN

</TABLE>


                     *SEE INSTRUCTION BEFORE FILLING OUT!
         INCLUDE BOTH SIDES OF THE COVER PAGE, RESPONSES TO ITEMS 1-7
     (INCLUDING EXHIBITS) OF THE SCHEDULE, AND THE SIGNATURE ATTESTATION


                                 SCHEDULE 13D
CUSIP NO.  449370 10 5                               PAGE   6   OF   21   PAGES
         --------------                                  -------  --------


<TABLE>
<CAPTION>
<S>    <C>                                                               <C>
1      NAME OF REPORTING PERSON
       S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
            Merrill Lynch Venture Capital Inc.
2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                 (a) / /
                                                                         (b) /x/
3      SEC USE ONLY
4      SOURCE OF FUND*

            AF
5      CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED
       PURSUANT TO ITEMS 2(d) or 2(e)

            Not Applicable
6      CITIZENSHIP OR PLACE OF ORGANIZATION

            Delaware

</TABLE>



<TABLE>
<CAPTION>
<S>               <S>    <C>
    NUMBER OF     7      SOLE VOTING POWER
      SHARES                  150,264
   BENEFICIALLY   8      SHARED VOTING POWER
     OWNED BY
                              129,409 shares of common stock
      EACH        9      SOLE DISPOSITIVE POWER
    REPORTING   
                              150,264
      PERSON      10     SHARED DISPOSITIVE POWER
       WITH 
                              129,409 shares of common stock

</TABLE>




<TABLE>
<CAPTION>
<S>    <C>                                                                             <C>
11     AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
            279,673 shares of common stock
12     CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES*          / /

            Not Applicable
13     PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

            1.52%
14     TYPE OF REPORTING PERSON*

            CO

</TABLE>


                 *SEE INSTRUCTION BEFORE FILLING OUT!
         INCLUDE BOTH SIDES OF THE COVER PAGE, RESPONSES TO ITEMS 1-7
     (INCLUDING EXHIBITS) OF THE SCHEDULE, AND THE SIGNATURE ATTESTATION


                                 SCHEDULE 13D
CUSIP NO.  449370 10 5                            PAGE   7    OF   21   PAGES
         --------------                                -------   --------


<TABLE>
<CAPTION>
<S>    <C>                                                               <C>
1      NAME OF REPORTING PERSON
       S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
            ML Technology Ventures, L.P.
2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                 (a) / /
                                                                         (b) /x/
3      SEC USE ONLY
4      SOURCE OF FUND*

            AF
5      CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED
       PURSUANT TO ITEMS 2(d) or 2(e)

            Not Applicable
6      CITIZENSHIP OR PLACE OF ORGANIZATION

            Delaware

</TABLE>



<TABLE>
<CAPTION>
<S>               <C>    <C>
    NUMBER OF     7      SOLE VOTING POWER
      SHARES                  157,779
   BENEFICIALLY   8      SHARED VOTING POWER
     OWNED BY
                              135,880 shares of common stock
      EACH        9      SOLE DISPOSITIVE POWER
    REPORTING   
                              157,779
      PERSON      10     SHARED DISPOSITIVE POWER
       WITH 
                              135,880 shares of common stock

</TABLE>



<TABLE>
<CAPTION>
<S>    <C>                                                                             <C>
11     AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
            293,659 shares of common stock
12     CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES*          / /

            Not Applicable
13     PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

            1.59%
14     TYPE OF REPORTING PERSON*

            PN

</TABLE>


                      *SEE INSTRUCTION BEFORE FILLING OUT!
         INCLUDE BOTH SIDES OF THE COVER PAGE, RESPONSES TO ITEMS 1-7
     (INCLUDING EXHIBITS) OF THE SCHEDULE, AND THE SIGNATURE ATTESTATION


                                 SCHEDULE 13D
CUSIP NO.  449370 10 5                            PAGE   8    OF   21   PAGES
         --------------                                ------   --------


<TABLE>
<CAPTION>
<S>    <C>                                                               <C>
1      NAME OF REPORTING PERSON
       S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
            ML R&D Co., L.P.
2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                 (a) / /
                                                                         (b) /x/
3      SEC USE ONLY
4      SOURCE OF FUND*

            AF
5      CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED
       PURSUANT TO ITEMS 2(d) or 2(e)

            Not Applicable
6      CITIZENSHIP OR PLACE OF ORGANIZATION

            Delaware

</TABLE>



<TABLE>
<CAPTION>
<S>               <C>    <C>
    NUMBER OF     7      SOLE VOTING POWER
      SHARES                  157,779
   BENEFICIALLY   8      SHARED VOTING POWER
     OWNED BY
                              135,880 shares of common stock
      EACH        9      SOLE DISPOSITIVE POWER
    REPORTING   
                              157,779
      PERSON      10     SHARED DISPOSITIVE POWER
       WITH 
                              135,880 shares of common stock

</TABLE>



<TABLE>
<CAPTION>
<S>    <C>                                                                             <C>
11     AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
            293,659 shares of common stock
12     CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES*          / /

            Not Applicable
13     PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

            1.59%
14     TYPE OF REPORTING PERSON*

            PN

</TABLE>


                     *SEE INSTRUCTION BEFORE FILLING OUT!
         INCLUDE BOTH SIDES OF THE COVER PAGE, RESPONSES TO ITEMS 1-7
     (INCLUDING EXHIBITS) OF THE SCHEDULE, AND THE SIGNATURE ATTESTATION


                                 SCHEDULE 13D
CUSIP NO.  449370 10 5                              PAGE   9    OF   21   PAGES
         --------------                                 -------   --------

<TABLE>
<CAPTION>
<S>    <C>
1      NAME OF REPORTING PERSON
       S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
            Merrill Lynch R&D Management, Inc.
2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                 (a) / /
                                                                         (b) /x/
3      SEC USE ONLY
4      SOURCE OF FUND*

            AF
5      CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED
       PURSUANT TO ITEMS 2(d) or 2(e)

            Not Applicable
6      CITIZENSHIP OR PLACE OF ORGANIZATION

            Delaware

</TABLE>



<TABLE>
<CAPTION>
<S>               <C>    <C>
    NUMBER OF     7      SOLE VOTING POWER
      SHARES                  157,779
   BENEFICIALLY   8      SHARED VOTING POWER
     OWNED BY
                              135,880 shares of common stock
      EACH        9      SOLE DISPOSITIVE POWER
    REPORTING   
                              157,779
      PERSON      10     SHARED DISPOSITIVE POWER
       WITH 
                              135,880 shares of common stock

</TABLE>



<TABLE>
<CAPTION>
<S>    <C>                                                                             <C>
11     AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
            293,659 shares of common stock
12     CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES*          / /

            Not Applicable
13     PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

            1.59%
14     TYPE OF REPORTING PERSON*

            CO

</TABLE>


                     *SEE INSTRUCTION BEFORE FILLING OUT!
         INCLUDE BOTH SIDES OF THE COVER PAGE, RESPONSES TO ITEMS 1-7
     (INCLUDING EXHIBITS) OF THE SCHEDULE, AND THE SIGNATURE ATTESTATION


                                 SCHEDULE 13D
CUSIP NO.  449370 10 5                             PAGE   10    OF   21   PAGES
         --------------                                 --------   --------


<TABLE>
<CAPTION>
<S>    <C>                                                               <C>
1      NAME OF REPORTING PERSON
       S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
            Merrill Lynch KECALP L.P. 1987
2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                 (a) / /
                                                                         (b) /x/
3      SEC USE ONLY
4      SOURCE OF FUND*

            AF
5      CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED
       PURSUANT TO ITEMS 2(d) or 2(e)

            Not Applicable
6      CITIZENSHIP OR PLACE OF ORGANIZATION

            Delaware

</TABLE>



<TABLE>
<CAPTION>
<S>               <C>    <C>
    NUMBER OF     7      SOLE VOTING POWER
      SHARES                  10,000
   BENEFICIALLY   8      SHARED VOTING POWER
     OWNED BY
                              9,707 shares of common stock
      EACH        9      SOLE DISPOSITIVE POWER
    REPORTING   
                              10,000
       PERSON     10     SHARED DISPOSITIVE POWER
        WITH 
                              9,707 shares of common stock

</TABLE>



<TABLE>
<CAPTION>
<S>    <C>                                                                             <C>
11     AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
            19,707 shares of common stock
12     CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES*          / /

            Not Applicable
13     PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

            0.11%
14     TYPE OF REPORTING PERSON*

            PN

</TABLE>


                     *SEE INSTRUCTION BEFORE FILLING OUT!
         INCLUDE BOTH SIDES OF THE COVER PAGE, RESPONSES TO ITEMS 1-7
     (INCLUDING EXHIBITS) OF THE SCHEDULE, AND THE SIGNATURE ATTESTATION


                                 SCHEDULE 13D
CUSIP NO.  449370 10 5                             PAGE   11    OF   21   PAGES
         --------------                                 --------   --------


<TABLE>
<CAPTION>
<S>    <C>                                                               <C>
1      NAME OF REPORTING PERSON
       S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
            KECALP Inc.
2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                 (a) / /
                                                                         (b) /x/
3      SEC USE ONLY
4      SOURCE OF FUND*

            AF
5      CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED
       PURSUANT TO ITEMS 2(d) or 2(e)

            Not Applicable
6      CITIZENSHIP OR PLACE OF ORGANIZATION

            Delaware

</TABLE>



<TABLE>
<CAPTION>
<S>               <C>   <C>
    NUMBER OF     7      SOLE VOTING POWER
      SHARES                  10,000
   BENEFICIALLY   8      SHARED VOTING POWER
     OWNED BY
                              9,707 shares of common stock
      EACH        9      SOLE DISPOSITIVE POWER
    REPORTING   
                              10,000
      PERSON      10     SHARED DISPOSITIVE POWER
        WITH 
                              9,707 shares of common stock

</TABLE>



<TABLE>
<CAPTION>
<S>    <C>                                                                             <C>
11     AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
            19,707 shares of common stock
12     CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES*          / /

            Not Applicable
13     PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

            0.11%
14     TYPE OF REPORTING PERSON*

            CO

</TABLE>



                     *SEE INSTRUCTION BEFORE FILLING OUT!
         INCLUDE BOTH SIDES OF THE COVER PAGE, RESPONSES TO ITEMS 1-7
     (INCLUDING EXHIBITS) OF THE SCHEDULE, AND THE SIGNATURE ATTESTATION


                                 SCHEDULE 13D
CUSIP NO.  449370 10 5                           PAGE   12    OF   21   PAGES
          --------------                             --------   --------

<TABLE>
<CAPTION>
<S>    <C>                                                               <C>
1      NAME OF REPORTING PERSON
       S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
            Merrill Lynch & Co., Inc.
2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                 (a) / /
                                                                         (b) /x/
3      SEC USE ONLY
4      SOURCE OF FUND*

            AF
5      CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED
       PURSUANT TO ITEMS 2(d) or 2(e)

            Not Applicable
6      CITIZENSHIP OR PLACE OF ORGANIZATION

            Delaware

</TABLE>



<TABLE>
<CAPTION>
<S>               <C>    <C>
    NUMBER OF     7      SOLE VOTING POWER
      SHARES                  0
   BENEFICIALLY   8      SHARED VOTING POWER
     OWNED BY
                              274,996 shares of common stock
      EACH        9      SOLE DISPOSITIVE POWER
    REPORTING   
                              0
      PERSON      10     SHARED DISPOSITIVE POWER
       WITH 
                              274,996 shares of common stock

</TABLE>



<TABLE>
<CAPTION>
<S>    <C>                                                                             <C>
11     AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
            274,996 shares of common stock
12     CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES*          / /

            Not Applicable
13     PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

            1.49%
14     TYPE OF REPORTING PERSON*

            HC

</TABLE>


                     *SEE INSTRUCTION BEFORE FILLING OUT!
         INCLUDE BOTH SIDES OF THE COVER PAGE, RESPONSES TO ITEMS 1-7
     (INCLUDING EXHIBITS) OF THE SCHEDULE, AND THE SIGNATURE ATTESTATION



ITEM 1.   SECURITY AND ISSUER.

          Title of Security:  Common Stock, no par value.

          Issuer:  IDEC Pharmaceuticals Corporation

          The address of  the issuer's principal  executive offices is  11011
          Torreyana Road, San Diego, California  92121


ITEM 2.   IDENTITY AND BACKGROUND.

          (a)  ML/MS  Associates, L.P. (the "Partnership"), is organized as a
               California limited partnership.  The principal business of the
               Partnership  is  to   enter  into  a  series   of  contractual
               arrangements  with  IDEC Pharmaceuticals  Corporation  for the
               research,   design,  development   and  commercialization   of
               monoclonal  antibodies for the  treatment of  B-cell lymphomas
               and leukemias.

               The General Partner of the Partnership is MLMS Cancer Research
               Inc., a corporation organized  and existing under the  laws of
               the  state of  California.   The  stockholders of  the General
               Partner include each of the Limited Partners referenced below.
               A list of the directors  and executive officers of the General
               Partner is set forth as Schedule A hereto.

               There are four Limited Partners of the Partnership.  The first
               Limited Partner  of the Partnership is ML Venture Partners II,
               L.P.,  a  business development  company  under  the Investment
               Company Act of 1940, as amended (the "Investment Company Act")
               organized as  a Delaware  limited partnership.   The  Managing
               General Partner of ML Venture Partners II, L.P. is MLVPII Co.,
               L.P., a New York limited  partnership.  The General Partner of
               MLVPII  Co., L.P.  is Merrill  Lynch Venture  Capital Inc.,  a
               Delaware corporation and  an indirect, wholly-owned subsidiary
               of Merrill Lynch & Co., Inc.

               The second Limited Partner of the Partnership is ML Technology
               Ventures,  L.P. which  is  organized  as  a  Delaware  limited
               partnership.   The Managing  General Partner of  ML Technology
               Ventures, L.P.  is  ML  R&D  Co.,  L.P.,  a  Delaware  limited
               partnership.   The  General Partner  of  ML R&D  Co., L.P.  is
               Merrill Lynch R&D Management, Inc., a Delaware corporation and
               an indirect, wholly-owned  subsidiary of Merrill Lynch  & Co.,
               Inc.

               The third Limited Partner of  the Partnership is Merrill Lynch
               KECALP  L.P. 1987, a  closed-end investment company  under the
               Investment   Company  Act  organized  as  a  Delaware  limited
               partnership.  The General Partner of Merrill Lynch 
               KECALP L.P. 1987 is KECALP Inc., a Delaware corporation and an
               indirect, wholly-owned subsidiary of Merrill Lynch & Co., Inc.

               A list  of the  directors and  executive  officers of  Merrill
               Lynch & Co., Inc. is set forth as Schedule B hereto.

               The  fourth Limited  Partner  of  the  Partnership  is  Morgan
               Stanley Research Ventures, L.P.  The General Partner of Morgan
               Stanley  Research Ventures,  L.P. is  Morgan Stanley  Ventures
               Management  L.P.    The  General  Partner  of  Morgan  Stanley
               Ventures Management L.P. is Morgan Stanley Ventures, Inc.

          (b)  The address of the Partnership's principal business and office
               is 3000 Sand Hill Road, Menlo Park, California  94025.

          (c)  Not applicable.

          (d)  The  Partnership  has   not  been  convicted  in   a  criminal
               proceeding during the last five years.

          (e)  The  Partnership has not been a party to a civil proceeding of
               a judicial or administrative body during the last five years.

          (f)  Not applicable.


ITEM 3.   SOURCE AND AMOUNT OF FUNDS OR OTHER CONSIDERATION.

          In   connection  with  a  joint  venture  arrangement  among  ML/MS
          Associates,  L.P.  (the  "Partnership")  and  IDEC  Pharmaceuticals
          Corporation  ("IDEC"), the Partnership  contributed an aggregate of
          $11,500,000   toward   the  research,   design,   development,  and
          commercialization  of monoclonal antibodies for the treatment of B-
          cell lymphomas and leukemias.   Pursuant to such joint venture, the
          Partnership  was entitled  to certain  future  royalties and  other
          moneys attributable  to products  developed pursuant  to the  joint
          venture.    On  April  4,  1995, IDEC  issued  to  the  Partnership
          1,000,000 shares  of IDEC common stock and 69,375 shares of Class B
          preferred stock  of IDEC,  in consideration  for the  Partnership's
          rights to  such future  royalties and other  moneys from  the joint
          arrangement.   The  source of funds  for the  Partnership's initial
          contribution to  the joint venture  was the working capital  of the
          Partnership.



ITEM 4.   PURPOSE OF TRANSACTION.

          The  purpose of  the Partnership  in acquiring  the Shares  of IDEC
          Pharmaceuticals Corporation ("IDEC")  is to  obtain more  liquidity
          through acquiring  such shares  in exchange  for the  Partnership's
          interest in the joint venture arrangement referred to in Item 3.

          At  the present  time, the  Partnership has  no plans  or proposals
          which  relate  to  or  would  result in  any  of  the  transactions
          described in  subparagraphs (a) through  (j) of Item 4  of Schedule
          13D;  however, the  Partnership reserves  the right  to change  its
          plans  or intentions at  any time and  to take any  and all actions
          that it deems appropriate to  maximize the value of its investment,
          including  among other  things,  from time  to  time increasing  or
          decreasing the number of Shares  by acquiring additional shares, or
          by disposing of all or a portion  of the Shares through open market
          or privately negotiated transactions.



ITEM 5.   INTEREST IN SECURITIES OF THE ISSUER.

          (a)  Amount of Common Stock of IDEC Pharmaceuticals Corporation
               Beneficially Owned
               ------------------

          ML/MS Associates, L.P.:  372,048 Shares of Common Stock
          MLMS Cancer Research Inc.:  372,048 Shares of Common Stock
          ML Venture Partners II, L.P.:  279,673 Shares of Common Stock
          MLVPII Co., L.P.:  279,673 Shares of Common Stock
          Merrill Lynch Venture Capital Inc.:  279,673 Shares of Common Stock
          ML Technology Ventures, L.P.:  293,659 Shares of Common Stock
          ML R&D Co., L.P.:  293,659 Shares of Common Stock
          Merrill Lynch R&D Management, Inc.:  293,659 Shares of Common Stock
          Merrill Lynch KECALP L.P. 1987:  19,707 Shares of Common Stock
          KECALP Inc.:  19,707 Shares of Common Stock
          Merrill Lynch & Co., Inc.:  274,996 Shares of Common Stock

          Percent of Class
          ----------------

          ML/MS Associates, L.P.:  2.02%
          MLMS Cancer Research Inc.:  2.02%
          ML Venture Partners II, L.P.:  1.52%
          MLVPII Co., L.P.:  1.52%
          Merrill Lynch Venture Capital Inc.:  1.52%
          ML Technology Ventures, L.P.:  1.59%
          ML R&D Co., L.P.:  1.59%
          Merrill Lynch R&D Management, Inc.:  1.59%
          Merrill Lynch KECALP L.P. 1987:  0.11%
          KECALP Inc.:  0.11%
          Merrill Lynch & Co., Inc.:  1.49%

     (b) Number of Shares as to which such person has
            (i)     sole power to vote or to direct the vote:

               ML/MS Associates, L.P.:  0
               MLMS Cancer Research Inc.:  0
               ML Venture Partners II, L.P.:  150,264
               MLVPII Co., L.P.:  150,264
               Merrill Lynch Venture Capital Inc.:  150,264
               ML Technology Ventures, L.P.:  157,779
               ML R&D Co., L.P.:  157,779
               Merrill Lynch R&D Management, Inc.:  157,779
               Merrill Lynch KECALP L.P. 1987:  10,000
               KECALP Inc.:  10,000
               Merrill Lynch & Co., Inc.:  0

           (ii)     shared power to vote or direct the vote:

               ML/MS Associates, L.P.:  372,048 Shares of Common Stock
               MLMS Cancer Research Inc.:  372,048 Shares of Common Stock
               ML Venture Partners II, L.P.:  129,409 Shares of Common Stock
               MLVPII Co., L.P.:  129,409 Shares of Common Stock
               Merrill Lynch Venture  Capital Inc.:  129,409 Shares of Common
               Stock
               ML Technology Ventures, L.P.:  135,880 Shares of Common Stock
               ML R&D Co., L.P.:  135,880 Shares of Common Stock
               Merrill Lynch  R&D Management, Inc.:  135,880 Shares of Common
               Stock
               Merrill Lynch KECALP L.P. 1987:  9,707 Shares of Common Stock
               KECALP Inc.:  9,707 Shares of Common Stock
               Merrill Lynch & Co., Inc.:  274,996 Shares of Common Stock

          (iii)     sole power to dispose of or direct the disposition of:

               ML/MS Associates, L.P.:  0
               MLMS Cancer Research Inc.:  0
               ML Venture Partners II, L.P.:  150,264
               MLVPII Co., L.P.:  150,264
               Merrill Lynch Venture Capital Inc.:  150,264
               ML Technology Ventures, L.P.:  157,779
               ML R&D Co., L.P.:  157,779
               Merrill Lynch R&D Management, Inc.:  157,779
               Merrill Lynch KECALP L.P. 1987:  10,000
               KECALP Inc.:  10,000
               Merrill Lynch & Co., Inc.:  0

           (iv)     shared power to dispose or to direct the disposition of:

               ML/MS Associates, L.P.:  372,048 Shares of Common Stock
               MLMS Cancer Research Inc.:  372,048 Shares of Common Stock
               ML Venture Partners II, L.P.:  129,409 Shares of Common Stock
               MLVPII Co., L.P.:  129,409 Shares of Common Stock
               Merrill Lynch Venture Capital Inc.:  129,409  Shares of Common
               Stock
               ML Technology Ventures, L.P.:  135,880 Shares of Common Stock
               ML R&D Co., L.P.:  135,880 Shares of Common Stock
               Merrill Lynch R&D Management, Inc.:   135,880 Shares of Common
               Stock
               Merrill Lynch KECALP L.P. 1987:  9,707 Shares of Common Stock
               KECALP Inc.:  9,707 Shares of Common Stock
               Merrill Lynch & Co., Inc.:  274,996 Shares of Common Stock

          (c)  Not Applicable.

          (d)  Not Applicable.

          (e)  Not Applicable.


ITEM 6.   CONTRACTS,  ARRANGEMENTS,  UNDERSTANDINGS   OR  RELATIONSHIPS  WITH
          RESPECT TO SECURITIES OF THE ISSUER.

          MLMS  Cancer Research,  Inc. is  the General Partner  (the "General
          Partner")  of ML/MS  Associates,  L.P.  (the  "Partnership").    In
          accordance with Article 7  of the Limited Partnership  Agreement of
          ML/MS Associates, L.P. (the "Agreement"), the General Partner shall
          have full  and exclusive  charge and control  over the  management,
          conduct and operation of the Partnership in all respects and in all
          matters.  Pursuant to the Agreement, therefore, the General Partner
          has   full  control  over  the  Partnership's  investment  in  IDEC
          Pharmaceuticals Corporation.


ITEM 7.   MATERIAL TO BE FILED AS EXHIBITS.

          (a)  Limited Partnership Agreement of ML/MS Associates, L.P., dated
               as of the 17th day of February, 1987./*/

          (b)  Power  of Attorney  on behalf  of Merrill  Lynch &  Co., Inc.,
               dated as of the 30th day of November, 1994./*/

- -------------------
/*/  Incorporated by reference to the initial filing of the Schedule 13D as
     filed with the United States Securities and Exchange Commission by
     reporting persons on or about May 3, 1995.


                                  SIGNATURE

     After reasonable  inquiry and to the best of  my knowledge and belief, I
hereby certify that  the information  set forth  in this  statement is  true,
complete and correct.


Date:     ML/MS ASSOCIATES, L.P.

     By:  MLMS CANCER RESEARCH INC.
          General Partner



     By:  /s/ ROBERT F. AUFENANGER      
          ------------------------------


     MLMS CANCER RESEARCH, INC.


     By:  /s/ ROBERT F. AUFENANGER      
          ------------------------------


     ML VENTURE PARTNERS II, L.P.

     By:  MLVPII Co., L.P.
          Managing General Partner

     By:  Merrill Lynch Venture Capital Inc.
          General Partner


     By:  /s/ ROBERT F. AUFENANGER      
          ------------------------------


     MLVPII CO., L.P.

     By:  Merrill Lynch Venture Capital Inc.
          General Partner


     By:  /s/ ROBERT F. AUFENANGER      
          ------------------------------


     MERRILL LYNCH VENTURE CAPITAL INC.


     By:  /s/ ROBERT F. AUFENANGER      
          ------------------------------



     ML TECHNOLOGY VENTURES, L.P.

     By:  ML R&D Co., L.P.
          Managing General Partner

     By:  Merrill Lynch R&D Management, Inc.
          General Partner


     By:  /s/ ROBERT F. AUFENANGER      
          ------------------------------


     ML R&D CO., L.P.

     By:  Merrill Lynch R&D Management, Inc.
     General Partner


     By:  /s/ ROBERT F. AUFENANGER      
          ------------------------------



     MERRILL LYNCH R&D MANAGEMENT, INC.


     By:  /s/ ROBERT F. AUFENANGER      
          ------------------------------


     MERRILL LYNCH KECALP L.P. 1987

     By:  KECALP Inc.
          General Partner


     By:  /s/ ROBERT F. TULLY           
          ------------------------------


     KECALP INC.


     By:  /s/ ROBERT F. TULLY           
          ------------------------------


     MERRILL LYNCH & CO., INC.


     By:  /s/ MARCIA L. TU              
          ------------------------------


                                  SCHEDULE A

                          MLMS CANCER RESEARCH, INC.



Directors:
- ---------

     Kevin K. Albert (Chairman)
     Scott Halsted
     Robert F. Aufenanger



Officers:
- --------

     Kevin K. Albert   Chief Executive Officer
     Scott Halsted   President
     Robert F. Aufenanger   Vice President

                                  SCHEDULE B

                          MERRILL LYNCH & CO., INC.



Directors:
- ---------

     Herbert M. Allison, Jr.
     William O. Bourke
     Worley H. Clark
     Jill K. Conway
     Stephen L. Hammerman
     Earle H. Harbison, Jr.
     George B. Harvey
     William R. Hoover
     David H. Komansky
     Robert P. Luciano
     David K. Newbigging
     Aulana L. Peters
     John J. Phelan, Jr.
     John L. Steffens
     William L. Weiss


Officers:
- --------

     David H. Komansky  -  Chairman of the Board & Chief Executive Officer
     Herbert M. Allison, Jr.  -  President and Chief Operating Officer
     Stephen L. Hammerman  -  Vice Chairman and General Counsel
     John L. Steffens - Vice Chairman
     Thomas W. Davis - Executive Vice President
     Barry S. Friedberg - Executive Vice President
     Edward L. Goldberg -  Executive Vice President
     Jerome P. Kenney - Executive Vice President
     E. Stanley O'Neal - Executive Vice President
     Thomas H. Patrick - Executive Vice President
     Winthrop H. Smith, Jr. -  Executive Vice President
     Arthur Zeikel -  Executive Vice President
     Michael J. Castellano - Senior Vice President and Controller
     Paul W. Critchlow - Senior Vice President
     Theresa Lang - Senior Vice President and Treasurer
     Robert G. Murphy - Senior Vice President
     Patrick J. Walsh - Senior Vice President
     H. Allen White - Senior Vice President
     Joseph T. Willett - Senior Vice President and Chief Financial Officer
     Curtis C. Brown, Jr. - Vice President
     Keith L. Horn - Vice President
     Bruce E. Thompson, Jr. - Vice President
     Gregory T. Russo - Secretary
     Richard B. Alsop - Assistant Secretary
     Joan A. Clancy - Assistant Secretary
     Darryl W. Colletti - Assistant Secretary
     Lawrence M. Egan, Jr. - Assistant Secretary
     Margaret E. Nelson - Assistant Secretary
     Dauna R. Williams - Assistant Secretary