OT-15 is an innovative and highly specialized cell-based and personalized ERT for Mitochondrial Neurogastrointestinal Encephalomyopathy (MNGIE).


MNGIE is an ultra-rare, fatal, inherited metabolic disorder.   MNGIE is relentlessly progressive, with patients dying at an average age of 37.6 years.

The disease is caused by mutations in the nuclear TYMP gene encoding for the enzyme Thymidine Phosphorylase (TP). The resulting enzyme deficiency often leads to abnormalities of the digestive and nervous systems. GI symptoms can include abdominal pain, diarrhea, and intestinal blockage, which in turn lead to extreme weight loss and cachexia, Neurologic symptoms include mainly peripheral neuropathy, ptosis, ophthalmoplegia and hearing loss.


About OT-15

  • OT-15 is based on encapsulation of TP within autologous erythrocytes. Erythrocyte Encapsulated Thymidine Phosphorylase (EE-TP) was invented by Bridget Bax, Ph.D one of the world’s leading authorities on MNGIE. It addresses the fundamental lesion in MNGIE by replacement of the deficient enzyme thereby preventing or reversing the severe and life-threatening complications in patients with MNGIE. The encapsulation technology has the advantage of prolonging the circulatory half-life of enzymes and minimizing immunogenic reactions.
  • Several patients with urgent medical needs have obtained access to the therapy through compassionate use treatment. Administration of EE-TP was shown to be effective in reducing/eliminating the elevated plasma and urine concentrations of thymidine and deoxyuridine.
  • OT-15 has been granted orphan designation by both FDA and EMA. Upon approval, this will be the first approved treatment for a mitochondrial disease.