Pharmacological, pharmacokinetic and clinical profile of eletriptan (Relpax®), a new triptan for migraine

Eletriptan (Relpax®) is a new anti-migraine medication commonly referred to as triptans. Eletriptan is considered to reduce neuronal transmission of pain by causing vasoconstriction of dilated cranial vessels and inhibiting the release of neuropeptides from trigeminal nerves via activation of the 5-HT1B/1D receptors. Eletriptan showed selectivity, high affinities, and potent agonistic activity to human 5-HT1B/1D receptors. It selectively constricted the cranial artery relative to the coronary artery of the anesthetized dog and the isolated human specimen. The affinity to the 5-HT1B/1D receptors and the selectivity for the cranial artery over the coronary artery of eletriptan are higher than those of sumatriptan. Eletriptan inhibited the trigeminal nerve mediated inflammation in the rat dura mater with equal potency and efficacy to sumatriptan. Orally taken eletriptan was rapidly absorbed with good bioavailability. In clinical trials, eletriptan improved the headache response rate with rapid onset, and reduced headache recurrence. The functional impairments as well as associated symptoms such as nausea, vomiting, and photophobia were also improved by eletriptan. Eletriptan showed stable efficacy in chronic use against multiple attacks with no increase in adverse events. Eletriptan was well tolerated in patients and most adverse events were mild-to-moderate in nature.