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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
Under the Securities Exchange Act of 1934
SIGA PHARMACEUTICALS, INC
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(Name of Issuer)
COMMON STOCK
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(Title of Class of Securities)
826917106
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(CUSIP Number)
February 10, 1998
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(Date of Event Which Requires Filing of this Statement)
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)
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*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 NO. 826917106 13G Page 2 of 5 Pages
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1 NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
MedImmune, Inc.
I.R.S. #52-1555759
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2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A
GROUP (a) [ ]
(b) [ ]
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3 SEC USE ONLY
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4 CITIZENSHIP OR PLACE OF ORGANIZATION
State of Delaware
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NUMBER OF 5 SOLE VOTING POWER
SHARES
BENEFICIALLY 335,530
OWNED BY
EACH
REPORTING
PERSON
WITH
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6 SHARED VOTING POWER
-0-
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7 SOLE DISPOSITIVE POWER
335,530
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8 SHARED DISPOSITIVE
POWER
-0-
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9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
335,530
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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
5.3%
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12 TYPE OF REPORTING PERSON
CO
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Item 1(a) NAME OF ISSUER
SIGA Pharmaceuticals, Inc.
Item 1(b) ADDRESS OF ISSUER'S PRINCIPAL EXECUTIVE OFFICE
666 Third Avenue
New York, New York 10017
Item 2(a) NAME OF PERSON FILING
MedImmune, Inc.
Item 2(b) ADDRESS OF PRINCIPAL BUSINESS OFFICE
35 West Watkins Mill Road
Gaithersburg, Maryland 20878
Item 2(c) CITIZENSHIP
Delaware
Item 2(d) TITLE OF CLASS OF SECURITIES
Common Stock
Item 2(e) CUSIP NUMBER
826917106
Item 3 IF THIS STATEMENT IS FILED PURSUANT TO RULES 13d-1(b) OR 13d-
2(b), CHECK WHETHER THE PERSON FILING IS A:
(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 of 1940
(e) [ ] An Investment Adviser in accordance with
Section 240.13d-1(b)(1)(ii)(E)
(f) [ ] An employee benefit plan or endowment
fund in accordance with Section 240.13d-1(b)(1)(ii)(F)
(g) [ ] A parent holding company or control
person in accordance with Section 240.13d-1(b)(ii)(G)
(h) [ ] A savings association as defined in
Section 3(b) of the Federal Deposit Insurance Act
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(i) [ ] A church plan that is excluded from the
definition of an investment company under section
3(c)(14) of the Investment Company Act of 1940
(j) [ ] Group, in accordance with Section
240.13d-1(b)(1)(ii)(J)
If this Statement is filed pursuant to Section 240.13d-
1(c), check this box. [X]
Item 4 OWNERSHIP
(see cover page)
Item 5 OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS
If this statement is being filed to report the fact that as
of the date hereof the reporting person has ceased to be the
beneficial owner of more than five percent of the class of
securities, check the following [ ].
Item 6 OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER
PERSON
Not applicable
Item 7 IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH
ACQUIRED THE SECURITY BEING REPORTED ON BY THE PARENT HOLDING
COMPANY
Not applicable
Item 8 IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP
Not applicable
Item 9 NOTICE OF DISSOLUTION OF GROUP
Not applicable
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Item 10 CERTIFICATION
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.
SIGNATURE
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.
Dated: February 23, 1998
MEDIMMUNE, INC.
By: /s/DAVID LEBUHN
Name: DAVID LEBUHN
Title: TREASURER