Abstract Objective Assess the long‐term efficacy and safety of erenumab in patients with chronic migraine with acute medication overuse. Background Overuse of acute medication in patients with chronic migraine has been linked to greater pain intensity and disability and may diminish the effectiveness of preventive therapies. Methods This 52‐week open‐label extension study followed a 12‐week double‐blind placebo‐controlled study in which patients with chronic migraine were randomized 3:2:2 to placebo or once‐monthly erenumab 70 mg or 140 mg. Patients were stratified by region and medication overuse status. Patients received erenumab 70 mg or 140 mg throughout or switched from erenumab 70 to 140 mg (based on protocol amendment to augment safety data at higher dose). Efficacy was assessed in patients with and without medication overuse at parent study baseline. Results Of 609 patients enrolled in the extension study, 252/609 (41.4%) met the criteria for medication overuse at parent study baseline. At Week 52, the mean change in monthly migraine days from parent study baseline was −9.3 (95% confidence interval: −10.4, −8.1 days) in the medication overuse subgroup versus −9.3 (−10.1, −8.5 days) in the non‐medication overuse subgroup (combined erenumab doses); proportion of patients achieving ≥50% reduction in monthly migraine days at Week 52 was 55.9% (90/161; 48.2%, 63.3%) versus 61.3% (136/222; 54.7%, 67.4%), respectively. Among baseline users of acute migraine‐specific medication, the mean change in monthly migraine‐specific medication days at Week 52 was −7.4 (−8.3, −6.4 days) in the medication overuse subgroup versus −5.4 (−6.1, −4.7 days) in the non–medication overuse subgroup. Most patients (197/298; 66.1%) in the medication overuse subgroup transitioned to non‐overuse status by Week 52. Erenumab 140 mg was associated with numerically greater efficacy than erenumab 70 mg across all endpoints. No new safety signals were identified. Conclusion Long‐term erenumab treatment demonstrated sustained efficacy and safety in patients with chronic migraine with and without acute medication overuse.
Timing and durability of response to erenumab in patients with chronic migraine
Abstract Background Erenumab is a human anti‐calcitonin gene‐related peptide receptor monoclonal antibody approved for migraine prevention. We sought to further assess the temporal patterns of response to erenumab in patients with chronic migraine (CM), specifically the onset and sustainability of monthly migraine day (MMD) response. Methods This is a post hoc analysis of a 12‐week, randomized, double‐blind, placebo‐controlled study of erenumab for migraine prevention in patients with CM (≥15 headache days/month, including ≥8 migraine days/month). Onset and sustainability were assessed according to MMD reduction from baseline, with the following response categories: responders (≥50% reduction), partial responders (≥30% and <50%), or nonresponders (<30%). Results Among the erenumab 140 mg group ( n = 187), 54.0% (101/187) achieved a response at any month during the study with a median time to onset of monthly response of 1 month. This improvement was maintained in most patients with continued treatment. An initial response was achieved at Month 1 by 28.3% (53/187) of patients; 69.8% (37/53) of whom maintained a response at Months 2 and 3. Although many patients responded early, some patients required longer treatment to achieve a response; 79.4% (27/34) of initial partial responders and 21.0% (21/100) of initial nonresponders subsequently achieved a response. Similar findings were observed for the erenumab 70mg group ( n = 188). Conclusion A majority of erenumab‐treated patients with CM who achieved an initial response at Month 1 sustained this benefit. Many patients responded later with continued treatment. Our data support recommendations to assess outcomes after ≥3 months of preventive treatment with erenumab in CM.
Efficacy of erenumab in chronic migraine patients with and without ictal allodynia
Background Ictal cutaneous allodynia, common in chronic migraine, is associated with reduced responses to acute treatment with triptans. Allodynia’s impact on the efficacy of newer preventive treatments such as erenumab is unknown. Methods Post-hoc subgroup analysis of a double-blind, randomized, placebo-controlled 12-week study of erenumab in chronic migraine, contrasting those with no allodynia with those with moderate-severe allodynia assessed with the Allodynia Symptom Checklist-12, was undertaken. Results Of 648 randomized individuals with baseline Allodynia Symptom Checklist-12 scores, 386 (59.6%) had no allodynia and 153 (23.6%) had moderate-to-severe allodynia. Mean (standard deviation) baseline monthly migraine days were 17.6 (4.8) and 18.9 (4.3), respectively. Compared to placebo, the erenumab group had greater reductions in monthly migraine days and monthly acute migraine-specific medication days in both no allodynia and allodynia subgroups. Mean (95% confidence interval) treatment differences in change from baseline for monthly migraine days at week 12 were −2.5 (−3.7, −1.4) in the no allodynia subgroup and −3.3 (−5.3, −1.3) in the moderate-severe allodynia subgroup. Change in acute migraine-specific medication days were −3.3 (−4.3, −2.3) and −2.5 (−4.3, −0.8), respectively. Conclusions Erenumab’s efficacy in reducing monthly migraine days and acute migraine-specific medication days in chronic migraine was not impacted by the presence of moderate-severe ictal allodynia. Trial registration: ClinicalTrials.gov NCT02066415
The Spectrum of Response to Erenumab in Patients With Episodic Migraine and Subgroup Analysis of Patients Achieving ≥50%, ≥75%, and 100% Response
Objective To assess the efficacy of erenumab at the ≥50%, ≥75%, and 100% reduction in monthly migraine days (MMD) response thresholds, using data from the 6‐month double‐blind treatment phase (DBTP) of the Study to Evaluate the Efficacy and Safety of Erenumab in Migraine Prevention (STRIVE) pivotal clinical trial. Methods Enrolled patients with episodic migraine (EM; ≥4 MMD and <15 monthly headache days) were randomized (1:1:1) to erenumab 70 mg (n = 312), erenumab 140 mg (n = 318), or placebo (n = 316) once monthly. We determined the proportions of patients with ≥50%, ≥75% and 100% reduction in MMD over the last 3 months of the STRIVE DBTP (months 4 through 6) and conducted post hoc analyses to contextualize the treatment benefit in patient subgroups achieving, and not achieving, these response thresholds. Outcome measures included changes in MMD, acute migraine‐specific medication days (MSMD), and patient‐reported outcomes. Results The proportions of patients with a reduction in MMD from baseline were greater for erenumab than for placebo at all response thresholds. As previously reported for the ≥50% response threshold, 135/312 (43.3%) of patients on erenumab 70 mg and 159/318 (50.0%) on erenumab 140 mg responded, vs 84/316 (26.6%) for placebo. At months 4 through 6, 65/312 (20.8%) and 70/318 (22.0%) of those on erenumab 70 mg and erenumab 140 mg, respectively, achieved ≥75% reductions vs 25/316 (7.9%) on placebo. A reduction of 100% response, which required no migraine days over 3 consecutive months based on observed data, was achieved by 10/312 (3.2%) of patients treated with erenumab 70 mg and 16/318 (5.0%) for erenumab 140 mg, vs 9/316 (2.8%) for placebo. At all response thresholds, responders achieved numerically greater reductions in mean MMD and MSMD, and greater improvements in disability than did the overall population; importantly, these remarkable responses were noted early. Meanwhile, 60/312 (19.2%) and 53/318 (16.7%) patients on erenumab 70 and 140 mg, respectively, had no reduction in MMD from baseline in months 4 through 6, compared with 104/316 (32.9%) patients on placebo. Conclusions The responses at the ≥50%, ≥75%, and 100% thresholds provide context for establishing realistic patient and physician expectations regarding the magnitude of treatment benefit that may be achieved by patients with EM responding to erenumab (STRIVE, NCT02456740).
Vascular safety of erenumab for migraine prevention
Background Previously published three-month placebo-controlled and one-year open-label clinical trial data have provided information on the efficacy and safety of erenumab. Methods Interim analysis was undertaken from an ongoing five-year open-label treatment phase after all patients completed three years in the open-label treatment phase or discontinued the study. Adult patients with episodic migraine enrolled in the open-label treatment phase initially received 70 mg erenumab monthly. A protocol amendment increased the dosage to 140 mg monthly to assess long-term safety of the higher dose. Safety and tolerability were assessed by monitoring adverse events, electrocardiograms, laboratory assessments, and vital signs. Results Of 383 patients enrolled in the open-label treatment phase, at data cutoff 235 (61.3%) remained in the study, all received 140 mg for ≥1 year. Median (Q1, Q3) exposure (70 or 140 mg) for all patients enrolled was 3.2 (1.3, 3.4) years. The most frequent adverse events (≥4.0/100 patient-years) were reported as viral upper respiratory tract infection, sinusitis, influenza, and back pain. Exposure-adjusted serious adverse event rates were 4.2/100 patient-years. There was no increase in cardiovascular events over time. Conclusions In this long-term study of a CGRP-receptor antibody, erenumab was found to be safe and well-tolerated with a spectrum and rate of adverse events consistent with shorter-term placebo-controlled studies. Trial registration ClinicalTrials.gov NCT01952574