DeGryse, Ronald E.

Background The Phase 3 REsearch Evaluating Migraine Prophylaxis Therapy (PREEMPT) trials demonstrated efficacy/tolerability of onabotulinumtoxinA for headache prevention in adults with chronic migraine. This post hoc analysis assessed time of onset of onabotulinumtoxinA after the first treatment in total and responder populations and consistency weekly through five treatment cycles. Methods In the 24-week, double-blind, placebo-controlled phase of PREEMPT, individuals were randomized 1:1 to onabotulinumtoxinA (155-195 U) or placebo every 12 weeks for two cycles. The primary pooled efficacy variable was change in headache days per 28 days at week 24. We assessed change in headache and migraine/probable migraine (hereafter migraine) days/week compared with baseline week 4. Results Baseline mean (SD) headache days/week (week 4 of baseline) for onabotulinumtoxinA (n = 688) and placebo (n = 696) were similar (4.8 [1.6] vs. 4.8 [1.6] days/week, respectively), as were migraine days/week (4.6 [1.7] vs. 4.6 [1.7] days/week). The effect of onabotulinumtoxinA on change in headache and migraine days/week was significantly greater than placebo at week 1, persisting from week 3 after the first treatment (−1.6 [2.2] vs. −1.1 [2.2] headache days/week [ p < 0.001] and −1.6 [2.2] vs. −1.1 [2.2] migraine days/week [ p < 0.001]). Headache and migraine days decreased in onabotulinumtoxinA responders beginning 1 week after treatment 1. Conclusions Treatment with onabotulinumtoxinA is associated with significant reductions in headache and migraine days/week at week 1, persisting after week 3, compared with placebo. Combined with earlier reports showing onabotulinumtoxinA treatment results in a persistent and progressive reduction in headache days over 56 weeks, it is suggested peak benefit may require multiple treatments. Trial registration number ClinicalTrials.gov: NCT00156910 and NCT00168428.

Background and purpose Onabotulinumtoxin A was effective and well tolerated for prophylaxis of headache in patients with chronic migraine ( CM ) in two randomized, double‐blind, placebo‐controlled, phase 3 trials. To further assess the safety and tolerability of onabotulinumtoxin A in CM prophylaxis in adults, the pooled safety data from four double‐blind, placebo‐controlled trials were analyzed. Methods The pooled analysis included two phase 2 and two phase 3 double‐blind, placebo‐controlled trials. The safety population was 2436 patients, 1997 of whom received ≥1 dose of onabotulinumtoxinA. The studies shared similar dosing intervals (approximately 12 weeks) with doses between 75 and 260 U. Safety assessments included adverse events ( AE s), physical examination and clinical laboratory tests. Results Onabotulinumtoxin A was safe and well tolerated, with a low discontinuation rate (3.4%) due to AE s. The majority of patients in this pooled analysis received doses between 150 and 200 U, with an average of 163 U per treatment cycle. Of the 1997 patients who received any onabotulinumtoxin A injections, 1455 patients (72.9%) reported at least one AE . Neck pain (12.6%) was the most common onabotulinumtoxin A ‐associated AE , followed by muscle weakness (8.0%), musculoskeletal stiffness (6.1%) and eyelid ptosis (4.6%). Serious AE s were infrequent, occurring in 5.4% of patients who received any onabotulinumtoxin A treatment and 3.0% of patients receiving placebo. AE s were consistent with the known tolerability profile of onabotulinumtoxin A . Conclusions Multiple treatments with onabotulinumtoxinA at doses of 75–260 U administered every 12 weeks, and up to five treatment cycles, were well tolerated for the prophylaxis of headache in adults with CM .