OBJECTIVE

The objective of this study was to assess the clinical benefits of onabotulinumtoxinA (BOTOX®) treatment on the symptoms of cervical dystonia and the frequency, severity, and associated symptoms of migraine in patients with cervical dystonia and concurrent migraine.

BACKGROUND

Botulinum toxin is established as first-line treatment of cervical dystonia. Recent clinical trials have shown onabotulinumtoxinA to be an effective prophylactic therapy for patients with chronic migraine, and onabotulinumtoxinA has been approved for use in this patient population by the Food and Drug Administration. Patients with headache associated with cervical dystonia have been identified as a specific subpopulation of patients in whom botulinum toxin treatment may be effective for controlling the symptoms of both conditions.

METHODS

An open-label pilot study was conducted for 7.5 months in patients at least 18 years old with primary cervical dystonia of moderate severity (baseline rating of at least 20 on the Toronto Western Spasmodic Torticollis Rating Scale) complicated by migraine headache meeting the International Classification of Headache Disorders-II criteria for migraines with or without aura. Each patient received 2 cycles of treatment at Visit 3 (baseline) and Visit 6 (Day 90). For cervical dystonia, each patient was injected with a maximum of 175 units. At the same visit, a maximum of 125 units was also injected for migraine using a fixed-site, fixed-dose injection paradigm, with additional cervical dystonia injection-site treatment to a maximum dose of 300 units. Patients were assessed following onabotulinumtoxinA injection and at follow-up on Visit 4 (Day 30), Visit 5 (Day 60), Visit 6 (Day 90), and at Visits 7, 8, and 9 (Days 120, 150, and 180). The primary outcome measures for this study were change in Toronto Western Spasmodic Torticollis Rating Scale total score for cervical dystonia and frequency of headache episodes per 28-day period. Migraine episodes were defined as at least 4 hours of sustained pain with no upper limit. An episode was considered new if the patient was pain free for at least 24 hours. Secondary study end points included number of headache days per month, headache intensity, headache disability (assessed using Headache Impact Test-6 and the Migraine Disability Assessment score scales), acute headache medication use, resource utilization, and allodynia pain. Adverse events were reported.

RESULTS

A total of 25 patients (24 women, mean age 50.5 years; mean age of disease onset 21.9 years) were enrolled in the study. Patients experienced improvement in cervical dystonia symptoms with significant reductions from baseline in Toronto Western Spasmodic Torticollis Rating Scale scores at 30, 60, 90, 120, 150, and 180 days (-9.84 ± 8.49, -12.67 ± 8.22, -13.63 ± 7.27, -14.92 ± 7.05, -14.76 ± 6.97, -14.49 ± 6.14, respectively, P < .0001 at all time points from a baseline of 31.03 ± 3.61). Changes from baseline were assessed using the t-test. Reductions in the number of headache episodes from baseline on concurrent onabotulinumtoxinA treatment for coexistent chronic migraine did not attain significance. However, patients experienced significant reductions from baseline in the number of headache days at 90, 120, and 180 days (-3.39 ± 6.78, P = .0289; -4.29 ± 7.94, P = .0194; -4.38 ± 7.99, P = .0178, respectively, from a baseline of 15.33 ± 6.76). Changes from baseline were assessed using the t-test. The change from baseline in Headache Impact Test-6 total scores was significant at 30, 60, 90, 150, and 180 days (3.21 ± 4.14, P = .0009; -3.04 ± 4.04, P = .0012; -2.41 ± 2.79, P = .0006; -2.59 ± 3.87, P = .0050; -3.09 ± 3.80, respectively, from a baseline of 22.68 ± 3.20). Changes from baseline were assessed using the t-test. The change from baseline in Migraine Disability Assessment was significant at 120, 150, and 180 days (-38.09 ± 47.87, P < .0001, Wilcoxon signed rank test; -16.91 ± 62.69, P = .0358, Wilcoxon signed rank test; -23.73 ± 40.57, P = .0122, t-test, respectively, from a baseline of 56.68 ± 50.41). There were no serious adverse events or treatment-related discontinuations.

CONCLUSIONS

Concurrent treatment with onabotulinumtoxinA is effective and well tolerated in controlling the symptoms of cervical dystonia complicated by concurrent migraine.