The title is misleading, as other medications have been used for migraine prophylaxis. This is the first drug, per the article, that has been specifically approved for migraine prophylaxis. Medications such as beta blockers and valproic acid are other medications used for migraine prophylaxis but were originally approved for other conditions.

Additionally, please note that this drug has already been approved in the US, since May.

Now, onto the meat of this. If I'm not mistaken, erenumab is a cgrp inhibitor that made much fanfare a few months ago in New England Journal of Medicine when two studies found a clinical benefit in cgrp.

Basically healthcare providers are prescribing this if you failed the aforementioned therapies for migraine prophylaxis (since those are way cheaper).

On a funnier note, medical students such as myself have started referring to all of these new biologic drugs as "what-the-f*-umabs" since they all have weird names and we can't keep up with the rapid development of them.