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Exhibit 10.1
 

 

MacAndrews & Forbes LLC
35 East 62nd Street
New York, New York 10065
 

   April 29, 2009

SIGA Technologies, Inc.
420 Lexington Avenue, Suite 408
New York, NY  10170

Attn:       Eric A. Rose, M.D.
Chief Executive Officer and Chairman of the Board

Ayelet Dugary
Chief Financial Officer

Ladies and Gentlemen:

Reference is made to that certain letter agreement (together with the term sheet
attached thereto, the "Letter Agreement"), dated June 19, 2008, by and between
MacAndrews & Forbes LLC and SIGA Technologies, Inc. (the "Company"), pursuant to
which, among other things, we agreed to invest, subject to the terms and
conditions set forth in the Letter Agreement, up to $8,000,000 in the Company,
with such commitment remaining available to the Company during the one year
period from the date of the Letter Agreement (the "Commitment Period").  We
shall also have the option, during the commitment period, to invest in the
Company on the commitment terms.

The parties hereby agree to amend the Letter Agreement to extend the Commitment
Period through June 19, 2010 and to increase the number of tranches pursuant to
the Investment Commitment and the Investment Option to no more than six.

This letter shall, upon execution, be binding on the parties hereto.  All rights
and obligations under the Letter Agreement, as amended by this letter, shall
remain in full force and effect until the earlier of (i) the execution of
definitive documentation or (ii) the expiration of the Commitment Period.
 
Neither this letter nor any of the provisions hereof may be amended, modified,
changed or waived except by an instrument in writing signed by the parties
hereto.  This letter shall be governed by and construed in accordance with the
laws of the State of New York.  This letter and the Letter Agreement contain the
full and entire understanding and agreement between the parties with regard to
the subject matters hereof and supersedes all prior understandings and
agreements relating to the matters set forth herein.  This letter may be
executed in counterparts, each of which shall be deemed to constitute an
original but all of which together shall constitute one and the same instrument.

                                Very truly yours,

                                MACANDREWS & FORBES LLC

                                By: /s/ Barry F. Schwartz              
                                       Barry F. Schwartz
                                       Executive Vice Chairman

 
 

AGREED AND ACCEPTED:

SIGA TECHNOLOGIES, INC.

By: /s/ Eric A. Rose
      Eric A. Rose, M.D.
      Chief Executive Officer and Chairman of the Board