Pierre Fabre is developing donitriptan, a piperazide 5-HT1D agonist, as a potential treatment for migraine [175854]. In January 2001, donitriptan had completed phase I trials for migraine and was scheduled to enter phase II development [396027]. This compound has an increased potency and, importantly, markedly higher intrinsic activity in comparison to the well described tryptamine derivatives, naratriptan, zolmitriptan and sumatriptan [295769].