Predicting Response to Onabotulinumtoxin A in Chronic Migraine

A year-long treatment with onabotulinumtoxin A (OnabotA) may effectively and safely reduce the number of monthly headaches in individuals with chronic migraine, particularly individuals with unilateral pain, according to a study published in the European Journal of Neurology.1,2

In a letter to the journal editor addressing comments on the publication, the study authors emphasized the fact that their main finding —that unilateral pain in chronic migraine may represent a predictive factor for responsiveness to OnabotA — is particularly the case in patients in whom treatment is initiated early (ie, within 1 month of chronic migraine onset).1 Lower headache-related pain intensity and disability at baseline were also found to be associated with more efficient migraine prophylaxis with OnabotA; however, this was not “discussed in detail,” the researchers pointed out.

The study authors emphasized: “We believe that the presence of unilateral pain identifies in a better way patients diagnosed with ‘pure’ migraines, with less tensional component and therefore with a higher likelihood of being responders to OnabotA.”2

The results are consistent with a 2017 study in which patients with chronic migraine and predominantly unilateral vs bilateral pain — as well as scalp allodynia and pericranial muscle tenderness — showed greater response to OnabotA.3

“We consider that ‘pure’ migraineurs (ie, those with unilateral pain and autonomic symptoms) as well as early treatment in [chronic migraine] could be two elements with a high predictive value in terms of effectiveness when OnabotA treatment is applied in patients with [chronic migraine],” concluded the study authors.

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  1. Domínguez C, Pozo-Rosich P, Leira Y, Leira R. Unilateral pain and shorter duration of chronic migraine are significant predictors of response to onabotulinumtoxin A. Eur J Neurol. 2018;25(4):e48.
  2. Barbanti P, Ferroni P. Onabotulinum toxinA in the treatment of chronic migraine: patient selection and special considerations. J Pain Res. 2017;10:2319-2329.
  3. Mathew NT, Kailasam J, Meadors L. Predictors of response to botulinum toxin type A (BoNTA) in chronic daily headache. Headache. 2008;48:194-200.