T Cells Treating Multiple Sclerosis

Q&A with Neil WarmaWarma

Opexa Therapeutics, Inc., is a publicly traded biotechnology company dedicated to the development of patient-specific cellular therapies for the treatment of autoimmune diseases The Company’s leading therapy candidate, Tcelna™, is a T-cell immunotherapy that is in a Phase IIb clinical development program (the Abili-T trial) for the treatment of secondary progressive multiple sclerosis (SPMS).

The Stem for Life Foundation recently spoke with Neil K. Warma, President and CEO of Opexa since June 2008. Mr. Warma has more than 20 years of executive level experience in the life sciences industry in the U.S., Europe, and Canada. His experience includes several senior management positions at Novartis Pharmaceuticals at its corporate headquarters in Basel, Switzerland, in international policy and advocacy and global marketing. Prior to joining Opexa, Mr. Warma served as President and CEO and a member of the Board of Directors of Viron Therapeutics, Inc., a privately held clinical stage biopharmaceutical company developing a novel class of protein therapeutics.


SFLF: Opexa Therapeutics lead platform uses T cells. Can you explain what these cells are and why they show potential for SPMS?

Warma: T cells are one type of white blood cell in the immune system. With MS, they become sensitized to myelin and cross the bloodbrain barrier into the central nervous system (CNS). Once in the CNS, these T cells cause the destruction of myelin. This demyelination causes nerve impulses to be slowed or halted and produces the symptoms of SPMS. We believe our T-cell platform shows potential for the treatment of MS as it re-educates the immune system to specifically recognize myelin-reactive T cells (MRTCs) as pathogenic and suppress them, thereby inhibiting further destruction of the myelin sheath.

SFLF: What is the prognosis for patients with SPMS, and what led to the FDA granting a Fast Track Drug Development designation to Opexa for the development of Tcelna to treat SPMS?

Warma: The prognosis for patients with SPMS is, unfortunately, very poor. SPMS is characterized by a steady accrual of irreversible disability. The physical, cognitive, and emotional complications of SPMS substantially reduce quality of life. As disability accumulates, independence is increasingly compromised. Unfortunately, the treatment options for these patients are very limited. Opexa was granted Fast Track Designation by the FDA in SPMS because of the clear unmet medical need and the potential Tcelna has to become the first safe and effective treatment for SPMS.

SFLF: How does Tcelna work for patients, and what does it mean that it is a “personalized” therapy?

Warma: The proposed mechanism of action for Tcelna encompasses a reduction in circulating MRTCs, and an up-regulation in the regulatory cellular components of the immune system. Tcelna is analogous (derived from the patient’s own blood) T-cell immunotherapy administered as a course of 5 doses over a year. Using a proprietary
epitope profiling assay, a patient’s myelin peptide reactivity is assessed prior to manufacture of the treatment, and the patient receives Tcelna tailored to his or her individual profile of MRTCs. Much like the concept behind vaccinations, this repeated exposure to the target antigens is intended to re-educate the patient’s immune system, inducing an immune response against the MRTCs and restoring immune regulation. Each year, every patient receives a personalized dose of Tcelna that is precisely tailored to match his or her disease profile.

SFLF: Opexa has another platform to produce monocyte-derived stem cells from blood. What do you expect these cells can be used for,and what are their advantages?

Warma: Opexa’s stem cell platform generates monocyte-derived stem cells (MDSC), which have been shown to differentiate into three main cell classifications: endoderm, mesoderm, and ectoderm. Examples of these are heart muscle cells, hepatic (liver) cells, skin, blood cells, and pancreatic cells. These differentiated cells are autologous, meaning there is no risk of rejection from the body since the original cells came from that same person. There is also
the potential to freeze one’s own stem cells through a banking process and use them when needed. This form of cellular therapy could conceivably provide differentiated cells for treatment of a variety of medical diseases. Opexa’s initial research has been focused on the generation of beta islet cells, which could then be either put directly back into the pancreas where they produce insulin or injected into the portal vein where these beta cells grow and divide within the liver tissue.

SFLF: There has been growing interest in the cell therapy industry by large pharmaceutical companies. Can you tell us about Opexa’s relationship with Merck?

Warma: Opexa and Merck Serono signed an option and licensing agreement in February of this year for development of Tcelna. It represented an important milestone in cell therapy, marking one of the first partnerships in cell therapy between a large multinational pharmaceutical company and a small biotech company. Potential payments to Opexa from the agreement could total $225 million not including royalties based upon the successful development and commercialization of Tcelna for SPMS. Opexa is very pleased to have partnered with Merck Serono, especially given their long-term strategic commitment to, and existing franchise position in, the field of multiple sclerosis.