Allergan has today announced that BOTOX® (botulinum toxin type A) has been licensed by the MHRA in the UK for the prophylaxis of headaches in adults who have chronic migraine (headaches on at least 15 days per month of which at least 8 days are with migraine)1. This is the first licence worldwide of BOTOX® for this indication, and is also the first prophylactic (preventative) treatment to receive a specific licence for patients with chronic migraine.

Chronic migraine can be a costly and disabling disorder that can have a devastating impact on the lives of an estimated 700,000 people in the UK suffering from the condition2, as well as their families. Patients suffering from chronic migraine are more likely to visit Accident and Emergency (A&E), general practitioners (GPs) or speciality care physicians than patients with less frequent episodes of migraine. However, although distinct from other types of migraine, approximately 80% of chronic migraine patients may not actually be diagnosed.3 Historically, treatment for chronic migraine has consisted of a combination of over-the-counter and prescription treatments such as triptans, tricyclic antidepressants, β-blockers and anti-epileptics.

“There is an unmet need for effective and well-tolerated therapies specifically designed and studied for the prophylaxis of headache in chronic migraine” said Scott Whitcup, M.D., Allergan’s Executive Vice President, Research and Development and Chief Scientific Officer. “The authorisation of BOTOX® marks an evolution in medical care for the prevention of headache in adults with chronic migraine. It is also a significant milestone in the history of BOTOX® and Allergan is proud to advance novel treatments in the field of neurology through our neurosciences research programme.”

PREEMPT: the largest clinical trial programme in chronic migraine

The PREEMPT (Phase III REsearch Evaluating Migraine Prophylaxis Therapy) programme evaluated the safety profile and efficacy of BOTOX® as a prophylactic (preventative) headache treatment in chronic migraine patients.3 PREEMPT4 is the largest clinical programme in chronic migraine and consists of two phase III clinical trials involving 1,384 adults. Patients were eligible for the study if they had a history of migraine and experienced 15 or more headache days of which at least 50% were migraine or probable migraine during the 28 day baseline period. In a pooled assessment, two thirds of the patients had previously been treated with at least one other headache prophylactic medication and nearly two thirds of the patients were overusing acute medications. During the 28-day baseline period, patients reported suffering from an average of 19.9 headache days (headache for 4 or more hours in any calendar day), of which an average of 19.1 were migraine/probable migraine days (migraine headache on 4 or more hours in any calendar day).

At the end of the 28 day baseline period, patients were randomised to receive either 155 – 195 units of BOTOX® administered as 31 injections (155 units) into 7 specific head and neck muscle with an additional up to 8 injections (up to 40 units) into 3 of these muscles that could be administered in a ‘follow the pain’ strategy, or placebo. Patients received 2 injection cycles in a 24 week double-blind phase and then 3 injection cycles in a 32 week open label phase.

– At baseline, patients in the BOTOX® treatment group had an average of 19.1 days with migraine. Patients in the placebo treated group had an average of 18.9 days with migraine. By week 24 following treatment, BOTOX® treated patients averaged 8.2 fewer migraine days, which was significantly greater than the change from baseline observed in placebo treated patients (6.2 days), p<0.001 – Patients treated with BOTOX® experienced significantly fewer headache days compared to those patients treated with placebo (47.1% of BOTOX® treated patients compared to 35.1% of placebo treated patients achieved ≥50% reduction from baseline in the number of headache days at the week 24 primary timepoint, p<0.001) – Following the open label phase of the trial (week 56), nearly 70% of BOTOX® treated patients experienced ≥50% reduction from baseline in migraine days – Patients treated with BOTOX® had significant improvement from baseline in their quality of life scores (MSQ scores) and in the amount of headache related disability (HIT6 scores) compared with those on placebo, indicating significant improvement in patients functioning, vitality, psychological distress, and overall quality of life Throughout the PREEMPT trials including the open label phase, patients received up to 5 courses of treatment with BOTOX® every 12 weeks. Most adverse events reported in the trials were mild to moderate and resolved without further problems. The treatment was generally well tolerated and the discontinuation rate was low in both treatment arms; 3.8% in the BOTOX® treated arm and 1.2% in the placebo arm4. “This is an important step forward in the management of chronic migraine and will hopefully bring additional recognition to this potentially disabling condition,” said Professor Peter Goadsby of the UCL- Institute of Neurology, London and University of California, San Francisco . “BOTOX® treatment has been shown to reduce the frequency of headache/migraine, which can bring important benefits for patients. Patients with frequent, chronic migraine, have long required evidence-based approaches and this announcement offers them a new option, providing a real advance for patients often significantly impacted by their condition.” Patients who may be suffering from chronic migraine should seek medical advice from neurologists or headache specialists to ensure proper diagnosis and care. Wendy Thomas, Chief Executive of The Migraine Trust says, “Chronic migraine is currently an under-researched, under-diagnosed and under-treated condition. We know that treatment with acute pain medication does not always work for these patients so we welcome new therapies, especially preventative medication, for this potentially disabling condition.” Lee Tomkins, Director at Migraine Action comments, “It is important that patients seek a referral to a specialist for help with chronic migraine as the condition is so often associated with depression and other medical co-morbidities. Within the UK, there are headache clinics offering specialist assistance and support to people with chronic migraine.”

About BOTOX®

BOTOX® is a prescription-only medical product that contains tiny amounts of highly purified botulinum toxin protein refined from the bacterium, Clostridium botulinum.

In the UK, BOTOX® is also indicated for the treatment of:

– blepharospasm (uncontrolled blinking of the eyelids)

– hemifacial spasm (a neuromuscular disorder characterised by unpredictable and involuntary twitching of facial muscles on one side of the face)

– cervical dystonia (a muscle condition affecting the neck making it difficult to hold the head up straight)

– severe axillary hyperhidrosis (excessive sweating) of the armpits

– cerebral palsy (dynamic equinus foot deformity in paediatric patients aged two years and older)

– upper limb spasticity (wrist and hand disability associated with stroke in adults)

In addition, Allergan’s botulinum toxin type A is licensed under the brand name of VISTABEL® for the treatment of glabellar lines (frown lines).

References

1. BOTOX® Summary of Product Characteristics

2. Natoli JL et al. Global prevalence of chronic migraine: a systematic review. Cephalalgia 2010;30(5):599-609.

3. Bigal ME et al. Chronic migraine in the population : burden, diagnosis and satisfaction with treatment Neurology 2008;71(8)559-566.

4. Dodick DW et al. OnabotulinumtoxinA for treatment of chronic migraine: pooled results from the double-blind, randomized, placebo-controlled phases of the PREEMPT clinical program. Headache 2010; e-publication ahead of print, 7 May, 2010.

5. Diener HC et al. OnabotulinumtoxinA for treatment of chronic migraine: results from the double-blind, randomized, placebo-controlled phase of the PREEMPT 2 trial. Cephalalgia. In press.

Source: Allergan, Inc.