After a long and winding road that included two Phase III detours, Chelsea Therapeutics International Ltd. moved forward with a new drug application (NDA) for its lead candidate Northera (droxidopa), an orally active synthetic precursor of norepinephrine, to treat symptomatic neurogenic orthostatic hypotension (NOH) in patients with primary autonomic failure, dopamine beta hydroxylase deficiency and nondiabetic autonomic neuropathy.