OnabotulinumtoxinA treatment for chronic migraine: experience in 52 patients treated with the PREEMPT paradigm.

OnabotulinumtoxinA (OnabotA) was approved for treatment of chronic migraine (CM) after publication of PREEMPT trials. Thus, we set out to evaluate the efficacy of OnabotA in a series of patients with CM treated according to the PREEMPT protocol. In May 2012 we began to offer OnabotA to patients with CM who did not respond to topiramate and at least one other preventive therapy (beta blocker and/or calcium channel antagonist). We prospectively recorded demographic data and the characteristics of migraine, and we assessed the modifications in monthly headache and migraine days, as well as the number of days of symptomatic medication and triptan intake. By September 2014 we had treated 52 patients (8 male, 44 female), whose age at treatment onset was 42.8 ± 12.7 years (range: 16-71) and age at migraine onset was 16.8 ± 7.8 years (3-32). In 43 of these patients (82.7%) symptomatic overuse of medication was observed at the onset of treatment. A total of 168 procedures were performed and after the first session, we observed a significant reduction in all the variables considered. Twelve (23.1%) patients failed to perceive a positive effect after the first procedure and it was not repeated in 4 of them. By contrast, there was a significant decreasing in all the variables evaluated compared to the baseline in the 39 patients that received a second series of injections. The use of OnabotA according to the PREEMPT paradigm is an effective treatment in patients with chronic migraine in a real-life setting.