The introduction of the CGRP mAbs migraine prevention therapies five years ago has seen a decrease in prescriptions of older oral preventive therapies such as antiseizure, antihypertensive, and antidepressant medications, according to a US study.
A retrospective study comprised de-identified data from 6,595 patients treated at the Stanford Headache Clinic, California across pre-CGRP mAb years of 2015-2017 and post-approval years of 2019-2021.
Erenumab was the first CGRP mAb to be FDA-approved in May 2018 followed by fremanezumab in Sept 2018, which did not have wide uptake, galcanezumab in Sept 2018 then eptinezumab in February 2020.
The study, published in the journal Headache [link here] found 15.7% of patients were prescribed any one of the four CGRP mAbs during 2019-2021.
As well, they reported a statistically significant decrease in the proportion of patients receiving any of the previous top 10 most prescribed preventive medications for migraine after the introduction of the CGRP mAbs (46.3% v 43.1%; p=0.001).
In particular, statistically significant decreases were seen for amitriptyline and nortriptyline, valproate, duloxetine, memantine, onabotA, propranolol, and verapamil.
There was no statistically significant change in venlafaxine or gabapentin prescriptions.
The investigators said it was not unexpected that the CGRP mAbs would divert patients away from a second or third oral medication.