An Open-Label Study to Evaluate the Safety of NP101 in the Treatment of Acute Migraine Over 12 Months

The primary objective is to evaluate the safety of long-term treatment with NP101 as assessed by: * Subject self-examination skin irritation scores * Adverse events * Changes in vital signs and ECG parameters The secondary objective is to evaluate the long term efficacy of NP101 as assessed by: * Headache pain free at two hours after patch activation for all initial acute migraine attacks treated with NP101 * Headache pain relief at two hours after patch activation for all initial acute migraine attacks treated with NP101 * Nausea free at two hours after patch activation for all initial acute migraine attacks treated with NP101 * Phonophobia free at two hours after patch activation for all initial acute migraine attacks treated with NP101 * Photophobia free at two hours after patch activation for all initial acute migraine attacks treated with NP101 * Migraine free at two hours after patch activation for all initial acute migraine attacks treated with NP101 This study will use an open-label design to assess the long term safety of NP101 (sumatriptan iontophoretic transdermal patch). Subjects who continue to be in good health (use of a triptan or use of an NP101 patch is not contraindicated) and received treatment (patch activation) with the study patch for a qualifying migraine under study NP101-007 will be considered eligible for enrollment into the open-label study. Subjects will be expected to remain in the study for up to 12 months.