Sustained response to onabotulinumtoxin A in patients with chronic migraine: real-life data

Abstract

Background: Treatment with onabotulinumtoxin A (BT-A) is safe and effective for chronic migraine (CM). Several studies assessed possible predictors of response to treatment with BT-A, but there is little knowledge on the frequency and predictors of sustained response. The aim of this study was to evaluate sustained response to BT-A in patients with CM. Main body: In this prospective open-label study, 115 patients with CM and treated with BT-A were consecutively enrolled in two Italian headache centers and followed up for 15 months. Anytime responders were defined as those patients who achieved a ≥ 50% reduction in headache days during any three-month treatment cycle compared with the 3 months prior to initiation of BT-A treatment. Sustained responders were defined as those who achieved a ≥ 50% reduction in headache days within the third treatment cycle and maintained response until the end of follow-up. Non-responders were defined as those patients who never achieved a ≥ 50% reduction in headache days during the follow-up. Headache characteristics prior to BT-A treatment were assessed in order to evaluate their ability in predicting treatment response. The 115 enrolled patients (84.3% female; median age 50 years) had a median migraine duration of 30 years (interquartile range 22-38). At the end of follow-up, 66 patients (57.4%) were classified as anytime responders. Among the 51 patients who achieved a clinical response within the third month of treatment, 33 (64.7%) were sustained responders. Patients with sustained response had a lower CM duration (median 31 vs 65 months; P = 0.030) and a lower number of headache days (median 25 vs 30; P = 0.013) at baseline compared with nonresponders. Conclusions: About two thirds of patients who gain ≥50% response to BT-A within the third cycle of treatment maintain this positive response over time. More recent onset of CM and more headache-free days at baseline are associated with sustained response. We suggest not to delay preventive treatment of CM with BT-A, in order to increase the likelihood to achieve sustained clinical response.

Benefits Beyond Headache Days With OnabotulinumtoxinA Treatment: A Pooled PREEMPT Analysis

“…In agreement with this survey, a real-world observational cohort study using the PREEMPT protocol suggests that approximately 25% of patients might not respond until after four treatment cycles and 1 year, cautioning against adjudicating responder/nonresponder status to avoid missing a significant percentage of patients who might benefit from onabotulinumtoxinA treatment [12]. Real-world data from headache centers in Italy also support the notion that the benefits of onabotulinumtoxinA treatment using the PREEMPT protocol are sustained, even in patients with a recent onset of CM [28]. Preliminary results also suggest that treatment using the PREEMPT protocol may be beneficial to patients with other chronic, difficult-to-treat headache disorders [29].…”

The Impact of OnabotulinumtoxinA vs. Placebo on Efficacy Outcomes in Headache Day Responder and Nonresponder Patients with Chronic Migraine

“…Consistent with these guidelines, a quarter of Italian headache physicians surveyed believed that patients achieving a ≥ 30% reduction in headache days were considered responders (instead of ≥ 50% reduction), and 40% of these clinicians believed that more than 4 treatment cycles were required before classifying a patient as a nonresponder [ 20 ]. Also supporting this guidance, a real-world study demonstrated that patients who do not achieve a 50% reduction in headache days by the third onabotulinumtoxinA treatment cycle still exhibit improvements in disability and headache-related impact [ 21 ]. However, the outcomes measured may also impact the perception of treatment response, as a prospective study of patients with CM conducted in Spain showed that migraine-associated disability was more closely related to headache pain intensity than to headache frequency [ 22 ].…”

Early Management of OnabotulinumtoxinA Treatment in Chronic Migraine: Insights from a Real-Life European Multicenter Study

“…Evidence suggests that about one quarter of patients treated with BT-A who develop a response to the drug within the first two cycles might lose their response during the fourth cycle, while a comparable proportion of patients develop a new-onset response to BT-A during the third or fourth cycle [29]. Response to BT-A may fluctuate over time, and not all responders show a sustained response to the drug [29,30]. Fluctuations in response to BT-A might be common in the long term if we consider each single patient.…”