EXHIBIT 99.1

        Opexa Appoints Lorin J. Randall to Board of Directors

    THE WOODLANDS, Texas--(BUSINESS WIRE)--Sept. 20, 2007--Opexa
Therapeutics, Inc. (NASDAQ:OPXA), a company dedicated to the
development and commercialization of cell therapies, has announced
that Lorin Jeffry (Jeff) Randall has joined its board of directors,
bringing the number of directors to six. Mr. Randall will also serve
as a member of the audit committee. Dr. Hung will resign from the
audit committee, but remain a member of the board of directors.

    Mr. Randall brings to Opexa extensive biotechnology senior
financial management experience. From 2004 to 2006, Mr. Randall was
senior vice president - chief financial officer of Eximias
Pharmaceutical Corporation, a development stage provider of oncology
therapeutics. From 2002-2004, Mr. Randall held the same position at
i-STAT Corporation, a manufacturer of medical diagnostic devices,
which was acquired by Abbott Laboratories in 2004. His career also
included senior management positions at CFM Technologies, a
semiconductor manufacturing equipment company; Greenwich
Pharmaceutical Corporation, a development stage provider of immune
system disease therapeutics; and Surgilase, a provider of surgical
lasers to hospitals and clinics.

    Mr. Randall received a B.S. in accounting from The Pennsylvania
State University and an M.B.A. from Northeastern University.

    David B. McWilliams, chief executive officer of Opexa, commented,
"Jeff has impressive and broad experience in managing both the
financial and operational aspects of publicly traded companies. His
skills and experience will provide us with helpful perspective as we
build our business."

    About Opexa Therapeutics

    Opexa Therapeutics develops and commercializes cell therapies to
treat autoimmune diseases such as multiple sclerosis, rheumatoid
arthritis, and diabetes. The Company is focused on autologous cellular
therapy applications of its proprietary T-cell and stem cell
therapies. The Company's lead product, Tovaxin(TM), a T-cell therapy
for multiple sclerosis, is in Phase IIb trials. The Company holds the
exclusive worldwide license for adult multipotent stem cells derived
from mononuclear cells of peripheral blood. The technology allows
large quantities of monocyte derived stem cells to be produced
efficiently for use in autologous therapy, thus circumventing the
threat of rejection. The Company is in preclinical development for
diabetes mellitus. For more information, visit the Opexa Therapeutics
website at www.opexatherapeutics.com.

    Safe Harbor Statement

    This press release contains "forward-looking statements,"
including statements about Opexa Therapeutics' growth and future
operating results, discovery and development of products, strategic
alliances and intellectual property, as well as other matters that are
not historical facts or information. These forward-looking statements
are based on management's current assumptions and expectations and
involve risks, uncertainties and other important factors, specifically
including those relating to Opexa Therapeutics' ability to obtain
additional funding, develop its stem cell technologies, achieve its
operational objectives, and obtain patent protection for its
discoveries, that may cause Opexa Therapeutics' actual results to be
materially different from any future results expressed or implied by
such forward-looking statements. Opexa Therapeutics undertakes no
obligation to update or revise any such forward-looking statements,
whether as a result of new information, future events or otherwise.

    CONTACT: Company Contact:
             Opexa Therapeutics, Inc.
             Lynne Hohlfeld, 281-719-3421
             lhohlfeld@opexatherapeutics.com
             or
             Investor Relations Contacts:
             Lippert/Heilshorn & Associates
             Kim Sutton Golodetz, 212-838-3777
             kgolodetz@lhai.com
             or
             Bruce Voss, 310-691-7100
             bvoss@lhai.com