Experience with onabotulinumtoxinA (BOTOX) in chronic refractory migraine: focus on severe attacks

Abstract

The objective of this study is to analyse our experience in the treatment of refractory chronic migraine (CM) with onabotulinumtoxinA (BTA) and specifically in its effects over disabling attacks. Patients with CM and inadequate response or intolerance to oral preventatives were treated with pericranial injections of 100 U of TBA every 3 months. The dose was increased up to 200 U in case of no response. The patients kept a headache diary. In addition, we specifically asked on the effect of BTA on the frequency of disabling attacks, consumption of triptans and visits to Emergency for the treatment of severe attacks. This series comprises a total of 35 patients (3 males), aged 24–68 years. All except three met IHS criteria for analgesic overuse. The number of sessions with BTA ranged from 2 to 15 (median 4) and nine (26%) responded (reduction of >50% in headache days). However, the frequency of severe attacks was reduced to an average of 46%. Oral triptan consumption (29 patients) was reduced by 50% (from an average of 22 to 11 tablets/month). Those six patients who used subcutaneous sumatriptan reduced its consumption to a mean of 69% (from 4.5 to 1.5 injections per month). Emergency visits went from an average of 3 to 0.4 per trimester (−83%). Six patients complained of mild adverse events, transient local cervical pain being the most common. Although our data must be taken with caution as this is an open trial, in clinical practice treatment of refractory CM with BTA reduces the frequency of disabling attacks, the consumption of triptans and the need of visits to Emergency, which makes this treatment a profitable option both clinically and pharmacoeconomically.

CGRP and PTX3 as Predictors of Efficacy of Onabotulinumtoxin Type A in Chronic Migraine: An Observational Study

“…Previous studies showed that CGRP levels are sensitive and specific in predicting response to OnabotA in CM, and also that CGRP plasma levels fall after effective treatment with OnabotA . Our study supports these results, showing again that CGRP levels are increased in peripheral blood of responders to treatment with OnabotA.…”

“…We classified patients in two groups according to their outcome: nonresponders (<50% reduction in frequency of headache) and responders (>50% reduction in frequency of headache). Responders were classified in moderate responders (50‐75% reduction in headache frequency) or excellent responders (>75% reduction in headache frequency) …”

“…Different studies have tried to find predictors of response to treatment with OnabotA either through clinical characteristics, neuroimaging features, or molecular biomarkers . Interictal GCRP levels have recently been described as predictors of response to OnabotA in CM when measured in peripheral blood or saliva …”

CGRP and VIP Levels as Predictors of Efficacy of Onabotulinumtoxin Type A in Chronic Migraine

“…It was not until this decade that the efficacy of pericranial injections of 155‐195 U of onabotA was shown in two large controlled phase III trials . This efficacy has also been reported in several open studies20‐23 and in this series in which three quarters of our patients showed an objective and subjective response to onabotA injections. The exact mechanism of action of pericranial injections of onabotA leading to migraine prevention is still unclear, and reliable potential predictors of response have not yet been identified.…”

Tackling chronic migraine: current perspectives

“…OnabotulinumtoxinA is an expensive preventive treatment for CM. However, cost could be reduced by less triptan use for the acute migraine attacks 49. A cost-effectiveness analysis showed that onabotulinumtoxinA reduced headache days by an estimated 38 days per year at a cost of £18 per headache avoided in adults with CM in United Kingdom 50…”