There is little evidence of systemic erenumab wearing-off among patients with chronic or episodic migraine, according to a post hoc analysis published in the journal Headache.
Erenumab is a monoclonal antibody drug delivered by monthly injection and was developed to prevent migraine. Some anecdotal evidence has suggested erenumab has a wearing-off effect, in which some patients have a return of migraine in the week prior to their next dose.
This analysis evaluated the potential wearing-off effect of erenumab among patients with episodic migraine (EM) with ≥4 to <15 migraine days and <15 headache days per month or chronic migraine (CM) with ≥8 migraine days and ≥15 headache days per month. Data were sourced from 4 double-blind randomized trials conducted in North America, Europe, Russia, Turkey, and Japan. Wearing-off was assessed by comparing the number of weekly migraine days in week 4 with the number of weekly migraine days during weeks 1 to 3 of each treatment cycle.
The patients who received 70 mg or 140 mg erenumab (n=1407) and placebo (n=864) were included in this analysis. Baseline demographics were generally well-balanced between study treatment groups. The patients were median age, 41-45 years, 84.6%-86.8% were women, and 58.8%-95.6% were taking acute migraine-specific medications. The use of migraine-specific medications was higher in the study conducted in Japan compared with the other study sites.
Overall, the wearing-off effect was minimal, in which weekly migraine days differed between week 4 and weeks 1 through 3 by less than 1 day among either the erenumab recipients or placebo recipients.
Among only responders, (placebo: 10.7%-27.8%; 70 mg erenumab: 19.1%-43.3%; 140 mg erenumab: 24.6%-51.9%) there was a subgroup of patients who experienced wearing-off, however, a similar proportion of erenumab and placebo recipients experienced the wearing-off effect.
Persistent wearing-off, defined as 2 or more consecutive months of wearing off, was observed among 3.3%-3.4% of placebo recipients, 0.0%-2.2% of 70 mg erenumab recipients, and 4.2%-4.3% of 140 mg erenumab recipients.
Stratified by consistent response, defined as ≥50% reduction of weekly migraine days over the first 3 weeks of the cycle for 2 or more consecutive cycles, 10.7%-11.0% of placebo, 19.1%-50.0% of 70 mg erenumab, and 35.3% of 140 mg erenumab recipients were consistent responders. Persistent wearing-off was observed among 14.3%-20.0% of the placebo, 4.2%-5.6% of the low-dose erenumab, and 4.2% among the high-dose erenumab groups.
No difference in erenumab steady-state serum concentrations at week 12 were observed on the basis of wearing-off.
The major limitation of this study was the short study durations. It remains unclear whether trends in wearing-off may change in the long-term.
Researchers noted that erenumab likely did not have a significant wearing-off effect during 6 months of treatment for migraine.
They concluded that, “Further research is needed to determine if wearing-off reported by some patients in clinical practice reflects a vulnerable and identifiable subgroup or is just reflective of normal fluctuations in migraine frequency or to cyclic fluctuations in a subgroup of patients.”
Disclosure: Multiple authors declared affiliations with industry. Please refer to the original article for a full list of disclosures.
This article originally appeared on Neurology Advisor
Dodick DW, Blumenfeld AM, Singh RBH, et al. Post hoc analysis of clinical trial data and pharmacokinetic data to assess wearing-off of erenumab within monthly treatment cycle. Headache. Published online October 13. doi:10.1111/head.14403