To test the efficacy of Mitochondrial Augmentation Therapy (MAT) to improve physiological and metabolic status of a patient with Kearns-Sayre syndrome (KSS)

A 14 year old girl with KSS with a known mtDNA deletion treated with MAT under IRB-approved compassionate use. Maternal mitochondria (confirmed non-deleted) were harvested from peripheral blood. Patient underwent leukapheresis and positively selected CD34+ cells were augmented with maternal mitochondria prior to infusion (2x10^6 cells/kg). The patient was followed for clinical and metabolic parameters 7 months after treatment.

There was a marked improvement in her function over 7 months. At base line she weighed 19 kg, she had only light/dark perception, she could not sit, walk or express words and had 1-2 seizures a week. Seven months after treatment, she had improved appetite and gained 3.6 kg.  She could reach to 2 cm² objects, sit independently, walk with an aid and express herself in short sentences. Her seizures resolved 4 months after treatment. Her normalized functional score on the International Pediatric Mitochondrial Disease Score improved from 91% to 57%. The ATP content of the peripheral blood lymphocytes increased.