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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C.  20549

SCHEDULE 13G
Under the Securities Exchange Act of 1934

Amendment No.:  1

Name of Issuer:  Idec Pharmaceuticals Corporation

Title of Class of Securities:  common stock, $.001 par value

CUSIP Number:  449370105



  (Date of Event Which Requires Filing of this Statement)

                     December 31, 1998

Check the appropriate box to designate the rule pursuant to
which this Schedule is filed:

/ / Rule 13d-1(b)
/X/ Rule 13d-1(c)
/ / Rule 13d-1(d)

*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).






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CUSIP Number: 449370105

1.  Name of Reporting Person
    I.R.S. Identification No. of Above Person

         Larry N. Feinberg
         

2.  Check the Appropriate Box if a Member of a Group

         a.   
         b.   

3.  SEC Use Only


4.  Citizenship or Place of Organization

         United States

Number of Shares Beneficially Owned by Each Reporting Person
With:

5.  Sole Voting Power:

         844,000

6.  Shared Voting Power:

         

7.  Sole Dispositive Power:

         844,000

8.  Shared Dispositive Power:

         

9.  Aggregate Amount Beneficially Owned by Each Reporting
Person

          844,000

10. Check Box if the Aggregate Amount in Row (9) Excludes
    Certain Shares





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11. Percent of Class Represented by Amount in Row (9)

          4.25%

12. Type of Reporting Person

          IN












































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Item 1(a) Name of Issuer:  Idec Pharmaceuticals Corporation

      (b) Address of Issuer's Principal Executive Offices:

          11011 Torreyana Road
          San Diego, California 92121

Item 2(a) - (c).  Name, Principal Business Address, and
Citizenship of Persons Filing:

          Larry N. Feinberg - United States citizen
          c/o Oracle Investment Management, Inc.
          712 Fifth Avenue
          45th Floor
          New York, New York 10019

    (d)   Title of Class of Securities:  common stock, $.001
          par value

    (e)   CUSIP Number:  449370105

Item 3.  If this statement is filed pursuant to Rule
13d-1(b)(1) or 13d-2(b) or (c) check whether the person
filing is:

    (a)  / / Broker or dealer registered under Section 15 of
             the Act,

    (b)  / / Bank as defined in Section 3(a)(6) of the Act,

    (c)  / / Insurance Company as defined in
             Section 3(a)(19) of the Act,

    (d)  / / Investment Company registered under Section 8
             of the Investment Company Act,

    (e)  / / Investment Adviser registered under Section 203
             of the Investment Advisers Act of 1940,

    (f)  / / Employee Benefit Plan, Pension Fund which is
             subject to the provisions of the Employee
             Retirement Income Security Act of 1974 or
             Endowment Fund,

    (g)  / / Parent Holding Company, in accordance with Rule
             13d-1(b)(ii)(G),





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    (h)  / / Savings association as defined in Section 3(b)
             of the Federal Deposit Insurance Act,

    (i)  / / Church plan excluded from the definition of an
             investment company under Section 3(c)(14) of
             the Investment Company Act,

    (j)  / / Group, in accordance with Rule 13d-
             1(b)(1)(ii)(H).

If this statement is filed pursuant to Rule 13d-1(c), check
this box. /X/

 Item 4. Ownership.
         
         (a) Amount Beneficially Owned:  844,000

         (b) Percent of Class:  4.25%

         (c) 0 shares with shared power to vote or to direct
             the vote; 844,000 shares with sole power to
             vote or to direct the vote; 0 shares with
             shared power to dispose or to direct the
             disposition of; 844,000 shares with the sole
             power to dispose or to direct the disposition
             of

Item 5.  Ownership of Five Percent or Less of a Class.

         As of December 23, 1998, the Reporting Person
         ceased to be a beneficial owner of more than five
         percent of the class of securities.

Item 6.  Ownership of More than Five Percent on Behalf of
         Another Person.

         N/A

Item 7.  Identification and Classification of the Subsidiary
         Which Acquired the Security Being Reported by the
         Parent Holding Company.
    
         N/A

Item 8.  Identification and Classification of Members of the
         Group.
    
         N/A



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Item 9.  Notice of Dissolution of the Group.
    
         N/A

Item 10.

    Certification for Rule 13d-1(c): By signing below I
certify that, to the best of my knowledge and belief, the
securities referred to above were not acquired and are not
held for the purpose of or with the effect of changing or
influencing the control of the issuer of the securities and
were not acquired and are not held in connection with or as
a participant in any transaction having that purpose or
effect.

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



    /s/ Larry N. Feinberg                   
    _________________________               
    Larry N. Feinberg                       
   
    February 11, 1999
    __________________
    Date





















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