TERMINATION AGREEMENT

EXHIBIT 2.1

TERMINATION AGREEMENT

This TERMINATION AGREEMENT (this "Agreement"), dated as of December 1, 2013, is entered into by and among PharmAthene, Inc. ("PharmAthene"), Theraclone Sciences, Inc. ("Theraclone"), and Taurus Merger Sub, Inc. ("Merger Sub").

WHEREAS, the parties hereto are party to that certain Agreement and Plan of Merger, dated as of July 31, 2013, among the parties and Steven Gillis, Ph.D., as representative of the Theraclone stockholders (the "Merger Agreement"), pursuant to which Merger Sub would be merged with and into Theraclone, with Theraclone as the surviving corporation (the “Merger”), and as a result of the Merger, Theraclone would become a direct, wholly owned subsidiary of PharmAthene;

WHEREAS, a meeting of the PharmAthene stockholders to vote on the Merger (the "PharmAthene Stockholder Meeting") is scheduled to take place on Tuesday, December 3, 2013;

WHEREAS, certain developments and communications have come to the attention of the parties, including (i) Theraclone's receipt of notification from the Biomedical Advanced Research and Development Authority informing Theraclone that their proposal “Broad-spectrum anti-influenza A M2e fully human monoclonal antibody TCN-032: Determination of efficacy in serious influenza disease” was not selected for funding under the current proposal, (ii) communications from certain PharmAthene stockholders indicating that they will not vote in favor of the Merger, (iii) a recommendation against the Merger by Institutional Shareholder Services; and (iv) the commencement of an action against the members of PharmAthene's board of directors in the Court of Chancery of the State of Delaware alleging that the PharmAthene Directors individually breached their fiduciary duties by recommending the Merger;

WHEREAS, based on the foregoing recent developments and communications, the parties have each concluded that it is unlikely that the Merger will be approved at the PharmAthene Shareholder Meeting, or any adjournments thereof;

WHEREAS, the parties have concluded that it is in their respective best interests and the best interests of their respective stockholders to terminate the Merger Agreement and to abandon the Merger; and

WHEREAS, Section 8.2(a)(v) of the Merger Agreement requires PharmAthene to pay to Theraclone a termination fee of up to one million dollars ($1,000,000) in certain circumstances (the "Termination Fee").

NOW, THEREFORE, the parties hereto hereby agrees as follows:

1.                  Termination. The parties hereto hereby terminate the Merger Agreement and abandon the Merger by mutual consent pursuant to section 8.1(a) of the Merger Agreement (the "Termination"). PharmAthene agrees to promptly cancel the PharmAthene Stockholder Meeting.

2.                  No Further Obligations. Except with respect to the confidentiality provisions set forth in the Confidentiality Agreement (as defined in the Merger Agreement), and except as set forth herein with respect to the Termination Payment (as defined below), neither party shall have any further obligations to the other under the Merger Agreement or otherwise; and from and after the date hereof, each party shall be free to conduct its business and affairs in the same manner as if the Merger Agreement had not been executed.

3.                  Termination Payment. In consideration of the Termination, and in recognition of the provisions of the Merger Agreement pertaining to the Termination Fee, PharmAthene shall promptly pay Theraclone One Million Dollars ($1,000,000) (the "Termination Payment"), by wire transfer before the close of business on December 2, 2013.

4.                  Mutual Release.

5.                  General Provisions.

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IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be duly executed and delivered as of the date first above written.