Tuesday, January 30, 2007

Opexa Achieves Midpoint in Patient Admissions in Phase IIb Trial of Tovaxin for Multiple Sclerosis

THE WOODLANDS, Texas--(BUSINESS WIRE)--Jan 30, 2007 - Opexa Therapeutics, Inc. (NASDAQ: OPXA), a company involved in the development and commercialization of cell therapies, announced today that it has admitted the first 75 patients in its 150-patient Phase IIb clinical trial of Tovaxin(TM) in multiple sclerosis. Enrollment is expected to be completed by mid-2007. There are currently 34 trial sites in the U.S., all of which are actively recruiting patients.

David McWilliams, president and chief executive officer of Opexa, commented, "Given the efficacy and safety demonstrated in our Phase I/II study of Tovaxin and the emerging understanding in the scientific literature of the involvement of pathogenic T-cells in multiple sclerosis, this trial has been highly anticipated in the MS community. We are excited about the enrollment interest we are receiving and feel comfortable that we will be able to achieve our 100% enrollment goal in the first half of this year."

Jim Williams, Ph.D., chief operating officer of Opexa, commented, "We are pleased to have reached this important milestone in our clinical program for the development of Tovaxin as a first line therapy for multiple sclerosis. The admission of 75 patients into the Phase IIb trial attests to the ability of Opexa to organize its clinical trials, including patient recruitment, site selection and manufacturing capacity as we meet the challenge of developing a patient-specific autologous T-cell vaccination therapy for multiple sclerosis."

As previously announced, this Phase IIb clinical study will include 150 patients in a multicenter, randomized, double blind, placebo-controlled trial designed primarily to evaluate the efficacy, safety and tolerability of the Tovaxin T-cell vaccination with clinically isolated syndrome (CIS) and relapsing-remitting MS (RR-MS) patients. A total of 100 patients will receive Tovaxin, while 50 will receive placebo. The study is designed as a two-arm, 52-week, parallel-group study, whereby patients will be given five subcutaneous injections at 0, 4, 8, 12 and 24 weeks. The analyses will be performed at the end of the 52-week study to assess the safety and efficacy of Tovaxin. The primary efficacy variable is the cumulative number of gadolinium-enhancing lesions on T1-weighted MRI scans summed over the Week 28, 36, 44, and 52 MRIs. The secondary efficacy variables are the cumulative number of new gadolinium-enhancing lesions at Weeks 28-52, the change in T2-weighted lesion volume, and the annualized relapse rate.

All patients who complete the trial will be eligible to participate in an optional one-year extension study, in which they will receive Tovaxin under an open-label protocol. The open-label study is being planned under a different protocol that will be submitted to the FDA.

About Opexa Therapeutics

Opexa Therapeutics develops and commercializes cell therapies to treat autoimmune diseases such as MS, 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 type 1 diabetes.

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.


Opexa Therapeutics, Inc.
Lynne Hohlfeld, 281-719-3421
Investor Relations Contacts:
Lippert/Heilshorn & Associates
Kim Sutton Golodetz, 212-838-3777
Bruce Voss, 310-691-7100