MT 300 is an injectable formulation of dihydroergotamine mesylate (DHE; a serotonin 5-HT1 receptor agonist) that is being developed by POZEN for the acute treatment of migraine. POZEN intends to present MT 300 as a prefilled syringe that can be administered alone, or with an autoinjector. In September 2003, POZEN announced that it had formed a commercialisation agreement with Xcel Pharmaceuticals. Under the terms of the agreement Xcel will have exclusive rights to commercialise MT 300 in the United States, and will pay POZEN upfront and milestone payments, as well as royalties on future sales. In December 2002, POZEN submitted an NDA to the US FDA for MT 300 for the acute treatment of migraine with or without aura. In March 2003 POZEN announced that its New Drug Application (NDA) for MT 300 had been accepted for filing by the US FDA. Two phase III trials have been completed in the US. Both studies, the first involving 619 patients with migraine and the second (and final study) involving 550 patients with migraine, have produced promising results. POZEN received a US patent (6,495,535) with claims related to therapeutic packaging of dyhydroergotamine in a prefilled syringe. This is the first issued patent for MT 300. POZEN has multiple pending foreign patent applications. The patents have claims regarding liquid pharmaceutical compositions for the treatment of migraine, which contain concentrated dihydroergotamine.