[Answer] Adults with more than 12 months history of migraines were assigned randomly in a double-blinded study to receive treatment with experimental drug X or placebo. The primary efficacy measure was the reduction in the severity of the migraine attacks. Enrollment was 1200 subjects. Which clinical phase does this best describe?

Answer: Phase 3

Most relevant text from all around the web:

Adults with more than 12 months history of migraines were assigned randomly in a double-blinded study to receive treatment with experimental drug X or placebo. The primary efficacy measure was the reduction in the severity of the migraine attacks. Enrollment was 1200 subjects. Which clinical phase does this best describe? Adults with more than 12 months history of migraines were assigned randomly in a double-blinded study to receive treatment with experimental drug X or placebo . The primary efficacy measure was the reduction in the severity of the migraine attacks . Enrollment was 1200 subjects . Adults with more than a 12 -month history of migraines were assigned randomly in a double-blinded study to receive treatment with experimental drug X (10 or 20 mg/day) or placebo . The primary efficacy measure was the reduction in severity of the migraine attacks . Enrollment was 1200 subjects . Adults with more than a twelve ( 12 )-month history of migraines were assigned randomly in a double-blinded study to receive treatment with experimental drug X (10 or 20 mg/day) or placebo . The primary efficacy measure was the reduction in severity of the migraine attacks . Enrollment was twelve-hundred ( 1200 ) subjects . Adults with more than a 12 -month history of migraines were assigned randomly in a double-blinded study to receive treatment with...

Disclaimer: 

Our tool is still learning and trying its best to find the correct answer to your question. Now its your turn, "The more we share The more we have". Comment any other details to improve the description, we will update answer while you visit us next time...Kindly check our comments section, Sometimes our tool may wrong but not our users.

Are We Wrong To Think We're Right? Then Give Right Answer Below As Comment