Exhibit 99.1
Opexa Therapeutics Reports Positive Top-line Data in Phase I/II Dose
Escalation Trial with Tovaxin(TM) for Multiple Sclerosis
THE WOODLANDS, Texas--(BUSINESS WIRE)--April 3, 2007--Opexa Therapeutics,
Inc. (NASDAQ: OPXA), a company involved in the development and commercialization
of cell therapies, today announced positive top-line data in an open-label Phase
I/II dose escalation clinical trial of the investigational T-cell vaccine,
Tovaxin(TM), for multiple sclerosis. In this one-year, 10-subject dose
escalation clinical trial, Tovaxin therapy was shown to be safe and effective.
The "per-protocol" analysis of Tovaxin therapy achieved a 90% reduction (p =
0.0039) in annualized relapse rate (ARR) in subjects who received one of the
three dosage levels; the doses were 6 - 9 x 10(6), 30 - 45 x 10(6) or 60 - 90 x
10(6) attenuated T-cells. Subjects in the study received subcutaneous injections
of Tovaxin over a period of 20 weeks (0, 4, 12 and 20 weeks) and were monitored
for an additional 32 weeks.
The safety profile for all dosage levels revealed no severe adverse
reactions related to T-cell vaccination. With increasing dosage, an increase in
mild injection site reactions was observed and these resolved within 48 hours.
All subjects currently are enrolled in an extension study to collect
longitudinal safety and effectiveness data.
David McWilliams, president and chief executive officer of Opexa, commented,
"We are particularly encouraged by the data from this dose escalation trial.
While all three dosage levels were safe and effective, the group treated with
the 30 - 45 x 10(6) T-cell dose achieved a 100% reduction in ARR. The currently
enrolling Tovaxin IIb clinical trial is being conducted with the 30 - 45 x 10(6)
T-cell dose."
About TERMS
The Tovaxin 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. As of
March 19, 2007, Opexa reported that more than 110 patients have been enrolled in
the TERMS clinical trial and the Company expects enrollment to be complete by
mid 2007.
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.
The TERMS study is being conducted at 36 U.S. sites to evaluate the safety
and effectiveness of Tovaxin It is registered on the U.S. National Institutes of
Health-sponsored website, www.clinicaltrials.gov, where pharmaceutical companies
are required to register trials for medicines that will treat serious or
life-threatening diseases or conditions. For more information, visit the TERMS
website at www.tovaxin.com.
About T-cell Vaccination
For a T-cell vaccine to be effective, it should be able to induce T-cell
cytotoxic and/or regulatory immune responses against the pathogenic T-cells.
Studies of T-cell vaccine have indicated that T-cell vaccination with peripheral
blood-derived autologous myelin-peptide selected T-cells in multiple sclerosis
patients resulted in the in vivo induction of CD8+ cytotoxic T-cells and
CD4+CD25+FoxP3 Tregs specific for T-cell vaccine. The induction of
anti-idiotypic cytotoxic CD8+ effector T-cells and anti-ergotypic CD4+CD25+FoxP3
positive Tregs is believed to provide a therapeutically effective dual mechanism
of protection to patients treated with Tovaxin(TM). The observed regulatory
immune responses have been shown to collectively correlate with clinical
improvement in treated patients.
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 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.
Editor's Note:
In first and fourth paragraphs of this release, T-cell dosage levels include
the figure 10(6), which should be read as ten to the sixth power.
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
Bruce Voss, 310-691-7100
bvoss@lhai.com