Patients profiling for Botox® (onabotulinum toxin A) treatment for migraine: a look at white matter lesions in the MRI as a potential marker

Insights from 25 years of onabotulinumtoxinA in migraine - mechanisms and management

OnabotulinumtoxinA (BTX-A) was first linked to beneficial effects in migraine 25 years ago and was approved by the FDA for preventive treatment of chronic migraine in 2010. The treatment has since had a major impact on the well-being of people with chronic migraine. The clinical development programme for BTX-A and research since its approval have provided insights into the neuromodulatory sensory effect of BTX-A, how it can control chronic migraine despite its peripheral action, and the underlying biology of migraine as a disease. In this Review, we consider the impact that BTX-A has had on the management of chronic migraine and on the research field. We discuss the insights provided by clinical research, encompassing the clinical trials and subsequent real-world evidence, and the mechanistic insights provided by preclinical and translational research. We also provide an overview of future directions of research in the field BTX-A in migraine and the clinical translation of this research.

OnabotulinumtoxinA in Migraine: A Review of the Literature and Factors Associated with Efficacy

The efficacy of onabotulinumtoxinA (OnaB-A) as a preventative treatment for chronic migraine, emerging fortuitously from clinical observation is now supported by class one evidence and over two decades of real-world clinical data. There is still limited ability to predict a clinically meaningful response to OnaB-A for individual patients, however. This review summarises briefly the proposed mechanism of OnaB-A in chronic migraine, the literature of predictors of clinical response, and recent developments in the field.

Iron Deposits in Periaqueductal Gray Matter Are Associated with Poor Response to OnabotulinumtoxinA in Chronic Migraine

Previous studies have reported increased brain deposits of iron in patients with chronic migraine (CM). This study aims to determine the relation between iron deposits and outcome after treatment with OnabotulinumtoxinA (OnabotA). Demographic and clinical data were collected for this study through a prospective cohort study including 62 CM patients treated with OnabotA in the Hospital Clínico Universitario de Santiago de Compostela (Spain). Demographic and clinical variables were registered. Selected biomarkers in plasma during interictal periods (calcitonin gene-related peptide (CGRP) and pentraxin-3 (PTX3)) and neuroimaging changes (iron deposits in the red nucleus (RN), substantia nigra (SN), globus pallidus (GP), and periaqueductal gray matter (PAG), and white matter lesions (WML)) were determined. Subjects were classified in responders (≥50% reduction in headache days) or non-responders (<50%). Responders to treatment were younger (mean age difference = 12.2; 95% confidence interval (CI): 5.4–18.9, p = 0.001), showed higher serum levels of CGRP (≥50 ng/mL) and PTX3 (≥1000 pg/mL) and smaller iron deposits in the GP and PAG (mean difference = 805.0; 95% CI: 37.9–1572.1 μL, p = 0.040 and mean difference = 69.8; 95% CI: 31.0–108.6 μL, p = 0.008; respectively). Differences in PAG iron deposits remained significant after adjusting for age (mean difference = 65.7; 95% CI: 22.8–108.6 μL, p = 0.003) and were associated with poor response to OnabotA after adjustment for clinical and biochemical variables (odds ratio (OR) = 0.963; 95% CI: 0.927–0.997, p = 0.041). We conclude that larger PAG iron deposits are associated with poor response to OnabotA in CM.

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

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 non-responders.

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.

The Use of Botulinum Toxin in the Management of Headache Disorders

Tremendous progress has been made in the past decades for the treatment of headache disorders. Chronic migraine is the most disabling type of headache and requires the use of acute and preventive medications, many of which are associated with adverse events that limit patient adherence. Botulinum toxin (BoNT) serotype A, a neurotoxin derived from certain strains of Clostridium, disrupts neuropeptide secretion and receptor translocation related to trigeminal nociception, thereby preventing pain sensitization through peripheral and possibly central mechanisms. Ever since the first randomized controlled trial on onabotulinumtoxinA (onabotA) for migraine was published two decades ago, onabotA has been the only BoNT formulation approved for use in the prevention of chronic migraine. Superior tolerability and efficacy have been demonstrated on multiple migraine endpoints in many controlled trials and real-life studies. OnabotA is a safe and efficacious treatment for chronic migraine and possibly high-frequency episodic migraine. Further research is still needed to understand its mechanism of action to fully develop its therapeutic potential.

Response Predictors in Chronic Migraine: Medication Overuse and Depressive Symptoms Negatively Impact Onabotulinumtoxin-A Treatment

Background: Despite numerous studies that have investigated clinical, radiological, and biochemical response predictors, the clinical profile of those patients who might benefit from OnabotulinumtoxinA is still missing. The aim of the present study was to identify potential OnabotulinumtoxinA response predictors among several clinical characteristics and confirm OnabotulinumtoxinA efficacy and safety in chronic migraine (CM) prevention.

Methods: The study was conducted at the Headache Center—Neurology Clinic—Spedali Civili Hospital of Brescia. Eighty-four consecutive CM patients were enrolled, with a mean age of 48 years (SD 9.7) and a mean disease duration of 10.1 years (SD 6.6). The mean reported headache-days frequency was 22.5 (SD 5.9) per month, while the mean number of severe headache-days was 15.2 (SD 8.9) with a mean monthly medication intake of 33.2 (SD 5.6). The clinical characteristics analyzed as potential response predictors were: gender, disease duration, migraine characteristics (location, side constancy, unilateral autonomic and neurovegetative symptoms), previous prophylactic treatments, add-on therapies, withdrawal therapies, psychiatric (anxiety and depression symptoms) comorbidities and medication overuse.

Results: A significant reduction from baseline to 3, 6, 9, and 12 month treatment cycles in total headache days, high intensity headache days and triptans consumption per month was found. Depressive symptoms and medication overuse negatively predicted OnabotulinumtoxinA outcome.

Conclusions: Our results confirm the efficacy and safety of OnabotulinumtoxinA in CM. Depressive comorbidity and medication overuse, among all clinical variables, were the only significant response predictors. Such findings provide interesting insights regarding patients selection for OnabotulinumtoxinA treatment as, with the introduction of anti calcitonin gene-related (CGRP) monoclonal antibodies, clinicians will have to thoroughly judge and tailor among the many available therapeutic options now available. Future research might be needed to confirm our findings, in particular for its therapeutic implications.

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

OBJECTIVE

The aim of this study is to find a relation between several biomarkers in peripheral blood and outcome after treatment with onabotulinumtoxin A (OnabotA).

BACKGROUND

OnabotA is an effective treatment in chronic migraine (CM). Different studies have tried to find predictors of response to treatment, either with clinical characteristics, neuroimaging features, or molecular biomarkers; however, it is still not possible to predict the individual outcome.

METHODS

We measured serum levels of biomarkers of inflammation (IL-6, IL-10, TNF-α, and hs-CRP), endothelial dysfunction (PTX3 and sTWEAK), blood-brain barrier disruption (cFN), brain damage (S100b, NSE), and trigemino-vascular activation (CGRP) by ELISA in a group of CM patients treated with OnabotA and healthy controls. After 24 weeks, patients were classified in two groups according to their outcome considering variations in headache frequency: nonresponders (nonimprovement or improvement <50%) and responders (improvement >50%). We compared baseline levels of biomarkers between these groups.

RESULTS

Sixty-two patients diagnosed with CM (IHS 2013 criteria) who fulfilled criteria for treatment with OnabotA and 24 healthy controls were included. Fifteen patients did not respond to treatment (24.2%) and 47 were responders (75.8%). Pentraxin 3 (PTX3) serum levels (1455.4 ± 487.5 pg/mL versus 720.3 ± 334.1 pg/mL, P < .0001) and calcitonin gene-related peptide (CGRP) serum levels (133.1 ± 86.6 ng/mL versus 58.2 ± 91.7 ng/mL, P = .004) were significantly higher in responders than nonresponders. Serum basal levels of PTX3 >1000 pg/mL (AUC 0.908; 95% CI: 0.827-0.990) and CGRP >50 ng/mL (AUC 0.800; 95% CI: 0.652-0.947) were associated with good response to OnabotA treatment.

CONCLUSIONS

These results show that molecular markers of trigeminovascular activation (CGRP) and endothelial dysfunction (PTX3) are associated with response to OnabotA and may act as new biomarkers for the selection of treatment in chronic migraineurs.

A two years open-label prospective study of OnabotulinumtoxinA 195 U in medication overuse headache: a real-world experience

Background

The efficacy and safety of OnabotulinumtoxinA (BOTOX®) in adults with chronic migraine (CM) were demonstrated in the PREEMPT program. However, the dosage used in this study was flexible from 155 U to 195 U at the physician’s discretion. Therefore, the objective of this prospective study was to compare the efficacy and safety of OnabotulinumtoxinA 195 U vs. 155 U for the treatment of CM and medication overuse headache (MOH) during a 2-year period.

Methods

We prospectively evaluated the mean reduction in headache days, migraine days, acute pain medication intake days and Headache Impact Test (HIT)-6 score in 172 patients injected with OnabotulinumtoxinA 195 U. Successively, we compared the efficacy measures with data of 155 patients injected with OnabotulinumtoxinA 155 U and followed up for 2 years. All patients were affected by CM and MOH, and failed one or more previous detoxification and preventative therapies.

Results

Both OnabotulinumtoxinA 195 U and 155 U reduced significantly the number of headache and migraine days, acute pain medication intake days and HIT-6 score, when compared with the baseline measures. Nevertheless, OnabotulinumtoxinA 195 U proved to be superior of 155 U in all efficacy measures since the first injection and for all the 2 years of treatment, with the exception of the reduction in pain medication intake days that resulted significantly larger with 195 U only after the 4th injection. The safety and tolerability of the two doses were similar and treatment related adverse events were transient and mild-moderate.

Conclusions

This study represents the largest and longest post-marketing studies of doses comparison with OnabotulinumtoxinA in a real-life clinical setting.

Here, we demonstrate the superior efficacy of OnabotulinumtoxinA 195 U compared to 155 U in CM patients with MOH during a 2-year treatment period with similar safety and tolerability profile.

Electronic supplementary material

The online version of this article (doi:10.1186/s10194-016-0591-3) contains supplementary material, which is available to authorized users.