NT-3. Takeda/Regeneron/Amgen

Regeneron, in collaboration with Amgen, is developing neurotrophin-3 (NT-3), a neuronal growth factor, for the potential treatment of neuropathies, as well as Parkinson's disease (PD). The product was inlicensed from Takeda Chemical Industries [179174]. By May 1999, Regeneron had started phase I/II trials in patients who suffer constipation due to spinal cord injury, PD or other medical conditions [272155,325270]. Initial results, presented at the annual meeting of the American Gastroenterological Association in May 1999, showed that NT-3 exerted strong prokinetic effects [325270], which are thought to be due to increased cholinergic activity and a decrease in NO transmission and number of NO synthase-positive neurons [368906]. By 1994, Amgen had begun phase I/II trials on behalf of Amgen-Regeneron Partners for NT-3 in the US and Canada for the potential treatment for peripheral neuropathies [168371]. The mechanism by which NT-3 excities intestinal muscle is thought to involve increased non-cholinergic contractility, decreased non-adrenergic, non-cholinergic inhibitory neurotransmission, and a reduction in the number of NOS-positive neurons [368906].