The Safety and Tolerability of Kinetin, in Patients With Familial Dysautonomia

Familial dysautonomia (FD, also called Riley Day syndrome or hereditary sensory and autonomic neuropathy type III) is an autosomal recessive disease caused by a point mutation in the kinase complex associated protein (IKAP) gene sequence (1, 2). This leads to a tissue specific splicing defect with variable "skipping" of exon 20 (1, 3, 4). The consequence is a devastating congenital sensory neuropathy, affecting pain and temperature perception (5) as well as afferent information from the viscera (6). As a result, patients suffer recurrent aspiration pneumonias, respiratory insufficiency, proprioceptive ataxia, scoliosis and the long-term consequences of volatile blood pressure including renal failure (7) and left ventricular hypertrophy (8). In-vitro studies have shown that the plant hormone kinetin corrects the splicing defect and increases the production of normal IKAP protein levels in FD derived cell lines (9, 10). Preliminary studies in heterozygous carriers of the IKAP mutation showed that dietary supplementation with kinetin increased the production of correctly spliced IKAP mRNA, in white blood cells (11). Preliminary studies in patients with FD have demonstrated that kinetin also increases the expression of correctly spliced IKAP mRNA extracted from white blood cells. However, the effect of kinetin on mRNA levels in neuronal tissue is unknown. The overall objective of this study is to assess the safety and tolerability of administering kinetin in patients with FD. The specific aim of this proposal is to determine the safety of a once daily dose of kinetin in patients with FD using a dose ascending titration and to determine the long-term safety and tolerability during 3-years of receiving a maximum tolerated steady state dose of kinetin. The investigators hope to also demonstrate early proof of concept that kinetin enhances the ability of neuronal tissue to correctly splice IKAP mRNA.