Opexa (OPXA) presents Tovaxin® Data
OPXA presented clinical data highlighting efficacy data from OPXA’s Phase IIb TERMS clinical trial in a sub-population of patients that had previously not been exposed to or taken any drugs for the treatment of MS.
In this treatment-free or “naïve” subpopulation, patients treated with Tovaxin demonstrated a significant improvement in Annualized Relapse Rate (ARR) compared to those on placebo. In patients who had at least one relapse in the 12 months prior to enrolling in the study and who had no previous exposure to MS therapy (n=70), Tovaxin reduced their ARR by 64% compared to placebo (p=0.046). The overall ARR for Tovaxin-treated patients dropped to 0.18 relapses per patient per year by the end of the 52-week study. Additionally, 76% of Tovaxin treated patients remained relapse-free at 1 year compared with 60% of placebo patients.
- Prior treatment with Disease Modifying Therapies (DMTs), especially immuno-suppressants or broad acting T-cell therapies, may influence the ARR in the placebo group by imparting a long-term benefit or “legacy” effect. This could explain the observed decline in ARR for placebo controls in more recent MS clinical trials. The impact of prior therapies on the placebo group would indicate that despite a washout period to remove potential DMTs as defined by pharmacokinetics, a legacy effect might persist.
The Bottom Line: The analysis conducted on this patient subgroup provides critical information on clinical trial design. Eliminating a possible “legacy” effect due to previous exposure to MS drugs may increase study power to detect a treatment effect. Results identified in this population are encouraging and support OPXA’s plans to initiate a pivotal clinical study later this year. Tovaxin could be very well positioned to treat all MS patients who are faced with limited treatment options.