PharmAthene Presents New SparVax® Data At The Bacillus - ACT 2013 International Anthrax Conference

      PharmAthene Presents New SparVax® Data At The Bacillus - ACT 2013
                       International Anthrax Conference

PR Newswire

ANNAPOLIS, Md., Sept. 6, 2013

ANNAPOLIS, Md., Sept.6, 2013 /PRNewswire/ --PharmAthene, Inc. (NYSE MKT:
PIP) announced today that new data from the Company's SparVax^®
next-generation anthrax vaccine program were presented in two separate oral
presentations at the 2013 Bacillus – ACT international anthrax conference in
Victoria, British Columbia, Canada.

In a presentation entitled "Development of an Immunopotency Assay as a Release
and Stability Test for a Recombinant Protective Antigen (rPA) Anthrax
Vaccine," Dr. Peter Fusco, Vice President, Immunobiology and Assay Development
at PharmAthene, presented data showing the Company's progress in developing a
new functional assay to more accurately measure the stability and potency of
rPA, an important requirement for licensure by the United States Food and Drug
Administration (FDA).

"The issue of stability has historically been a major stumbling block for
other recombinant anthrax vaccine programs," said Dr. Fusco. "Current potency
assays, such as the Mouse Challenge Assay (MCA), are not optimal due to the
inherent variability of infectious challenge assays. There remains a clear
need for a more practical and sensitive alternative for potency testing of
anthrax vaccines."

Dr. Fusco continued, "PharmAthene has worked closely with the FDA and our
partner, the Biomedical Advanced Research and Development Authority (BARDA),
to develop more robust assays for anthrax vaccine development. Recently, the
FDA advised us that it has accepted the use of our Immunopotency Assay (IPA)
as a suitable replacement for the MCA. We are proud to be advancing
technologies for next-generation anthrax vaccine development that can provide
a superior alternative to existing technologies."

In a second oral presentation entitled "Development of Stability Assays for a
Recombinant Protective Antigen Anthrax Vaccine," Dr. Bradford Powell, Director
of Analytical Sciences for PharmAthene, presented additional data on the
Company's rPA assay development efforts.

The objective of these studies was to evaluate supportive analytical assays to
determine the potential correlation between the physicochemical structure and
function of rPA. In these experiments, Dr. Powell and his team evaluated the
effects of forced degradation of rPA resulting from increases in temperature
and pH level. The data showed a trend suggesting a correlation between the
structural and functional stability of rPA.

Dr. Powell commented, "By better informing our understanding of how changes to
the structure of the rPA molecule impacts its function, or potency, we can
fulfill an important requirement of the FDA and provide further confidence in
the robustness of our stability data. The continuing refinement of these
supportive assays may lead to the development of faster, more cost-effective
assays to gauge stability and potency of rPA."

"We are very encouraged about the opportunities for our SparVax^® anthrax
vaccine program," remarked Eric I. Richman, President and Chief Executive
Officer. "The benefits of rPA-based anthrax vaccines are well-established and
we believe our program is at the forefront of efforts in this field. Most
importantly, SparVax^® is expected to meet a fundamental objective of Project
BioShield, which was established to encourage the development and acquisition
of newer medical countermeasures that offer potential improvements in cost,
convenience, safety and effectiveness for the U.S. government and its

PharmAthene's rPA anthrax vaccine program has been funded in whole or in part
with federal funds from the National Institute of Allergy and Infectious
Disease, National Institutes of Health and BARDA.

Important Information about the Proposed Merger with Theraclone Sciences, Inc.

This communication is being made in respect of the proposed merger involving
Theraclone and PharmAthene. On August 1, 2013, PharmAthene filed with the SEC
a current report on Form 8-K, which includes the merger agreement and related
documents. PharmAthene expects to file shortly a registration statement on
Form S-4 with the SEC, which will contain a preliminary proxy
statement/prospectus/consent solicitation and other relevant materials, and
plans to file with the SEC other documents regarding the proposed transaction.
The final proxy statement/prospectus/consent solicitation will be sent to the
stockholders of PharmAthene and Theraclone in connection with the stockholder
votes on matters relating to the proposed transaction. The proxy
statement/prospectus/consent solicitation contains information about
PharmAthene, Theraclone, the proposed transaction, and related matters.

In addition to receiving the proxy statement/prospectus/consent solicitation
and proxy card by mail, stockholders will also be able to obtain the proxy
statement/prospectus/consent solicitation, as well as other filings containing
information about PharmAthene, without charge, from the SEC's website
( or, without charge, by contacting Stacey Jurchison at
PharmAthene at (410) 269-2610.

No Offer or Solicitation

This communication is not intended to and does not constitute an offer to sell
or the solicitation of an offer to subscribe for or buy or an invitation to
purchase or subscribe for any securities or the solicitation of any vote or
approval in any jurisdiction in connection with the merger or otherwise, nor
shall there be any sale, issuance or transfer of securities in any
jurisdiction in contravention of applicable law. No offer of securities shall
be made except by means of a prospectus meeting the requirements of Section 10
of the Securities Act of 1933, as amended.

Participants in Solicitation

PharmAthene and its executive officers and directors may be deemed to be
participants in the solicitation of proxies from PharmAthene's stockholders
with respect to the matters relating to the proposed merger. Theraclone may
also be deemed a participant in such solicitation. Information regarding
PharmAthene's executive officers and directors is available in Amendment No. 1
to PharmAthene's proxy statement on Schedule 14A, filed with the SEC on May 9,
2013. Information regarding such executive officers and directors and
regarding any interest that PharmAthene, Theraclone or any of the executive
officers or directors of PharmAthene or Theraclone may have in the transaction
will be set forth in the final proxy statement/prospectus/consent solicitation
that PharmAthene will file with the SEC in connection with its stockholder
vote on matters relating to the proposed transaction. Stockholders will be
able to obtain this information by reading the final proxy
statement/prospectus/consent solicitation when it becomes available.

About PharmAthene

PharmAthene is a leading biodefense company engaged in the development and
commercialization of next generation medical countermeasures against
biological and chemical threats. PharmAthene's current biodefense portfolio
includes the following product candidates:

  oSparVax^® - a next generation recombinant protective antigen (rPA) anthrax
  orBChE bioscavenger - a medical countermeasure for nerve agent poisoning by
    organophosphorous compounds, including nerve gases and pesticides
  oValortim^® - a fully human monoclonal antibody for the prevention and
    treatment of anthrax infection

In addition, in May 2013, the Delaware Supreme Court issued its ruling on the
appeal in our litigation with SIGA Technologies, affirming the Court of
Chancery's finding that SIGA was liable for breach of contract, reversing its
finding of promissory estoppel, and remanding the case back to the Court of
Chancery to reconsider the appropriate remedy and award of attorney's fees and
expert witness costs in light of the Supreme Court's opinion. For more
information about PharmAthene, please visit

Forward-Looking Statement Disclaimer

Except for the historical information presented herein, matters discussed may
constitute forward-looking statements within the meaning of the Private
Securities Litigation Reform Act of 1995 that are subject to certain risks and
uncertainties that could cause actual results to differ materially from any
future results, performance or achievements expressed or implied by such
statements. Statements that are not historical facts, including statements
preceded by, followed by, or that include the words "will"; "potential";
"believe"; "anticipate"; "intend"; "plan"; "expect"; "estimate"; "could";
"may"; "should"; or similar statements are forward-looking statements. Such
statements include, but are not limited to those referring to the potential
for the generation of value, ability to leverage funding sources, potential
for revenue, and potential for growth. PharmAthene disclaims any intent or
obligation to update these forward-looking statements. Risks and
uncertainties include, among others, failure to obtain necessary shareholder
approval for the proposed merger with Theraclone and the matters related
thereto; failure of either party to meet the conditions to closing of the
transaction; delays in completing the transaction and the risk that the
transaction may not be completed at all; failure to realize the anticipated
benefits from the transaction or delay in realization thereof; the businesses
of PharmAthene and Theraclone may not be combined successfully, or such
combination may take longer, be more difficult, time-consuming or costly to
accomplish than expected; operating costs and business disruption during the
pendency of and following the transaction, including adverse effects on
employee retention and on business relationships with third parties; the
combined company's need for and ability to obtain additional financing; risk
associated with the reliability of the results of the studies relating to
human safety and possible adverse effects resulting from the administration of
the combined company's product candidates; unexpected funding delays and/or
reductions or elimination of U.S. government funding for one or more of the
combined company's development programs; the award of government contracts to
competitors; unforeseen safety issues; unexpected determinations that these
product candidates prove not to be effective and/or capable of being marketed
as products; as well as risks detailed from time to time in PharmAthene's Form
10-K and quarterly reports on Form 10-Q under the caption "Risk Factors" and
in its other reports filed with the U.S. Securities and Exchange Commission
(the "SEC"). In particular, there is significant uncertainty regarding the
level and timing of sales of Arestvyr™ and when and whether it will be
approved by the U.S. FDA and corresponding health agencies around the world.
PharmAthene cannot predict with certainty if or when SIGA will begin
recognizing profit on the sale thereof and there can be no assurance that any
profits received by SIGA will be significant. In its May 2013 decision, the
Delaware Supreme Court reversed the remedy ordered by the Court of Chancery
and remanded the issue of a remedy back to the trial court for reconsideration
in light of the Supreme Court's opinion. As a result, there can be no
assurance that the Chancery Court will issue a remedy that provides
PharmAthene with a financial interest in Arestvyr™and related products or any
remedy. In addition, significant additional research work, non-clinical
animal studies, clinical trials, and manufacturing development work remain to
be done with respect to SparVax^® and our other product candidates. At this
point there can be no assurance that SparVax^® or any of our other product
candidates will be shown to be safe and effective and approved by regulatory
authorities for use in humans. Copies of PharmAthene's public disclosure
filings are available from its investor relations department and its website
under the investor relations tab at

SOURCE PharmAthene, Inc.

Contact: Stacey Jurchison, PharmAthene, Inc., Phone: (410) 269-2610,
Press spacebar to pause and continue. Press esc to stop.