Sustained reductions in migraine days, moderate-to-severe headache days and days with acute medication use for HFEM and CM patients taking fremanezumab: Post-hoc analyses from phase 2 trials

Background In phase 2 and 3 studies, fremanezumab, a monoclonal CGRP antibody, was an effective preventive treatment for high-frequency episodic migraine (HFEM) and chronic migraine (CM). Objective Post-hoc analyses evaluated population-wise 50%, 75% and 100% responder rates, and the extent to which individual responders sustained a 50%, 75% and 100% reduction in migraine days, moderate-to-severe (M/S) headache days and days of acute medication use during all three treatment months of the fremanezumab phase 2 studies. Design/methods HFEM patients received either placebo or three once-monthly injections of 225 mg or 675 mg. CM patients received either placebo or three once-monthly injections of 900 mg, or an initial loading dose of 675 mg and subsequent injections of 225 mg. Patients reported headache-related data daily using an electronic diary. Results In the HFEM study, the percent of patients on fremanezumab doses 225 mg and 675 mg were greater compared to the percent of placebo patients with sustained 50% reduction in migraine days (39% and 35% vs. 10% for placebo, both p < 0.0001), M/S headache days (36% and 38% vs. 16% placebo, p = 0.0017 and p = 0.0007 respectively), and acute medication use days (36% and 27% vs. 8% placebo, p < 0.0001 and p = 0.0003). Likewise, although there were fewer patients with sustained 75% reduction, there were increases in the percent of patients on fremanezumab 225 mg and 675 mg in the HFEM study relative to placebo patients in migraine days (19% and 11% vs. 3% placebo, p = 0.0002 and p = 0.0176), M/S headache days (19% and 15% vs. 2% placebo, p = 0.0001 and p = 0.0011) and days of acute medication use (16% and 8% vs. 2% placebo, p = 0.0005 and p = 0.0377). In the CM study, there were increases in the percent of patients on fremanezumab 675/225 mg and 900 mg with 50% sustained reduction in M/S headache days (32% and 40% vs. 15% placebo, p = 0.0058 and p = 0.0002) and days of acute medication use (26% and 22% vs. 11% placebo, p = 0.0098 and p = 0.0492). There were also increases in the percent of patients on fremanezumab 675/225 mg and 900 mg compared to patients on placebo with 75% sustained reduction in M/S headache days (10% and 13% vs. 3%, p = 0.0665 and p = 0.0203). Few patients had 100% sustained reductions in these parameters in either study. Conclusions Post-hoc results must be interpreted with caution; nonetheless, a statistically significant percentage of patients who initially responded to fremanezumab within 1 month sustained this response over the subsequent 2 months. Sustained reduction in individual patients may provide a novel patient-centric, clinically meaningful endpoint for future trials assessing the effectiveness of preventive migraine treatments. Trials are registered as as NCT02025556 and NCT02021773.