Treatment with onabotulinumtoxinA not only reduces the number of headache days in patients with chronic migraine, but also reduces headache severity, according to a pooled analysis presented at the 2016 Annual Meeting of the American Headache Society in San Diego, CA.
Data from the Phase 3 Research Evaluating Migraine Prophylaxis Therapy (PREEMPT) trial outlining changes in headache frequency were previously presented.
For this pooled analysis, patients with chronic migraine were randomized to receive either onabotulinumtoxinA or placebo in 2 12-week treatment cycles over a 24-week double-blind phase. Headache-day severity was assessed at baseline and 24 weeks, with treatment responders defined as those who achieved ≥1-grade improvement in average daily headache severity (ADHS) score at 24 weeks vs baseline.
Overall, 1384 patients were included in the study. At baseline, 37.3% + 27.3% of the onabotulinumtoxinA group (n=688) reported severe/moderate headache days compared to 37.0% + 27.3% of the placebo group (P= .58 and P= .97, respectively). At week 24, the proportion of patients in the onabotulinumtoxinA group with severe/moderate headache days dropped to 21.3% + 15.6% vs 26.3% + 15.6% in the placebo group (P< .001). Significantly more patients in the onabotulinumtoxinA group demonstrated >1-grade improvement in ADHS score from baseline to 24-week follow-up compared to placebo (35.8% vs 23.1%, P<.001).
“… In addition to the previously reported benefit of onabotulinumtoxinA on reducing headache-day frequency, this analysis demonstrates a reduction in daily headache severity, which is clinically meaningful to patients with CM, enabling them to be more active,” the authors wrote.
Aurora SK, Halker R, Pozo-Rosich P, DeGryse R, Adams A, Matharu M. Abstract PF28. The Impact of OnabotulinumtoxinA on Severe Headache Days: PREEMPT 24-Week Pooled Analysis. Presented at: 2016 American Headache Society Annual Meeting. June 9-12, 2016; San Diego, CA.