The Durability of OnabotulinumtoxinA for the Treatment of Chronic Migraine: CLARITY Pilot Study (P7.186)

Abstract

Objective: To evaluate the durability of benefit with onabotulinumtoxinA when given for 7-9 cycles on the number of headache (HA) days for patients with a confirmed diagnosis of chronic migraine. Background: Limited data exists on the durability of benefit beyond 5 cycles for the treatment of chronic migraine with onabotulinumtoxinA. Methods: Retrospective medical records review for patients with chronic migraine per ICHD - III beta criteria with 15 or more HA days per month. Patients must have had a baseline visit and at least 7 onabotulinumtoxinA injection cycles with an interval of 12 weeks (+/- 2 weeks) between injections. Dosing must have been within the range of 155-195U using the PREEMPT injection paradigm. Abstracted data included dose, headache days, MIDAS, HIT-6, and adverse events. Results: Thirty-three patients qualified with a minimum of 7 injections cycles. Of these patients, 17 had 8 cycles and 10 had 9 cycles. Mean HA days at baseline, cycles 7 and 9 were 19.08, 6.25 and 6.57, respectively. Mean HA free days at baseline, cycles 7 and 9 were 10.92, 23.75 and 23.43, respectively. Proportion of patients achieving >50% reduction in HA days at cycles 7 and 9 were 85% and 90%, respectively. Proportion of patients considered incapacitated based on MIDAS scores at baseline and cycle 7 were 53% and 12%, respectively. For HIT-6, 50% of patients had > 5 point reduction in score by cycle 7. No serious adverse events were reported. Conclusions: Results suggest durability of benefit for onabotulinumtoxinA based on the reduction in HA days after 7 treatments and in this small series of patients, through 9 treatments. OnabotulinumtoxinA demonstrated long-term improvements in migraine related disability as evaluated by the MIDAS and HIT-6 instruments. Results warrant investigation in a larger study to better understand the durability of onabotulinumtoxinA in clinical practice for chronic migraine. Study Supported by: Allergan Inc.

Disclosure: Dr. Blumenfeld has received personal compensation for activities with Pfizer Inc., Allergan Inc., Medtronic Inc., Merck & Co. Inc., Forest, and Keller Laboratories. Dr. Blumenfeld has received research support from Allergan Inc., Medtronic Inc., GlaxoSmithKline Inc., and Keller Laboratories. Dr. Inocelda has received personal compensation for activities with Allergan Inc. as an advisory board member. Dr. Cunanan has received personal compensation for activities with Allergan Inc. Dr. Purdy has received personal compensation for activities with Allergan Inc., Salix, and Astellas. Dr. Purdy has received research support from Allergan Inc., Salix, and Astellas. Dr. Dalfonso has received personal compensation for activities with Allergan Inc., Salix, and Astellas. Dr. Dalfonso has received research support from Allergan Inc., Salix, and Astellas. Dr. Magar has received personal compensation for activities with Allergan Inc., Salix, and Astellas. Dr. Magar has received research support from Allergan Inc., Salix, and Astellas.