Opexa Therapeutics, Inc. (NASDAQ:OPXA), a company developing Tcelna ™, a novel T-cell therapy for multiple sclerosis (MS), today announced the initiation of a Phase IIb clinical trial of Tcelna in patients with Secondary Progressive Multiple Sclerosis (SPMS). Several patients have already been enrolled in the study and enrollment is expected to increase rapidly as additional sites begin screening and enrolling patients in the coming weeks. Tcelna is the first ever personalized T-cell therapy for MS patients and has received Fast Track Designation from the United States Food and Drug Administration (FDA) for the treatment of SPMS. The therapy is specifically tailored to each patient’s individual disease profile and has demonstrated superior safety and encouraging indications of efficacy in previous clinical studies in MS that included the treatment of SPMS patients. There is currently only one FDA-approved treatment for SPMS but safety warnings have severely restricted its use.
The newly initiated trial, named Abili-T, is a randomized, double-blind, placebo-controlled clinical study in SPMS patients who demonstrate evidence of disease progression without associated relapses. The trial is expected to enroll 180 patients at approximately 30 leading clinical sites in the U.S. and Canada with each patient receiving two annual courses of Tcelna treatment consisting of five subcutaneous injections per year. The study will assess a number of clinical endpoints to evaluate the efficacy and safety of Tcelna in patients with SPMS. The primary efficacy outcome of the trial is the percentage of brain volume change (atrophy) at 24 months. Study investigators will also measure several important secondary outcomes commonly associated with MS including disease progression as measured by the Expanded Disability Status Scale (EDSS), annualized relapse rate (ARR) and changes in disability as measured by EDSS and the Multiple Sclerosis Functional Composite (MSFC).
In multiple previously conducted clinical trials for the treatment of patients with MS, Tcelna has demonstrated one of the safest side effect profiles of any marketed or development-stage MS therapy, as well as encouraging efficacy signals indicating Opexa’s therapy may have the potential to be both safe and effective for the treatment of both SPMS and RRMS patients. In Phase I/II studies involving SPMS patients treated with Tcelna (n=36), 80 percent of the patients treated with Tcelna showed no evidence of disease progression at 24 months (a 50% improvement, with respect to patients showing evidence of disease progression, over historical controls). Following two years of treatment, a subset of these patients (n=10) reported no worsening of their physical or psychological condition. Additionally, in 21 years of cumulative follow up in the same SPMS patients treated with Tcelna, the annualized relapse rate for this same subset of patients was reduced significantly compared to baseline and only one patient experienced a relapse during this time.