botulinum toxin type A, 50 unit, 100 unit and 200 unit powder for solution for injection (Botox ) SMC No. (692/11) Allergan Ltd

Transcription

1 Resubmission botulinum toxin type A, 50 unit, 100 unit and 200 unit powder for solution for injection (Botox ) SMC No. (692/11) Allergan Ltd 08 March 2013 The Scottish Medicines Consortium (SMC) has completed its assessment of the above product and advises NHS Boards and Area Drug and Therapeutic Committees (ADTCs) on its use in Scotland. The advice is summarised as follows: ADVICE: following a resubmission botulinum toxin type A (Botox ) is not recommended for use within NHS Scotland. Indication under review: the prophylaxis of headaches in adults with chronic migraine (headaches on at least 15 days per month of which at least 8 days are with migraine). In pooled analysis of the two pivotal phase III studies, botulinum toxin type A significantly reduced the frequency of headache days compared with placebo. The submitting company did not present a sufficiently robust clinical and economic analysis to gain acceptance by SMC. Overleaf is the detailed advice on this product. Chairman, Scottish Medicines Consortium Published 08 April 2013 Page 1

2 Indication The prophylaxis of headaches in adults with chronic migraine (headaches on at least 15 days per month of which at least 8 days are with migraine). Dosing Information The recommended reconstituted botulinum toxin type A dose for treating chronic migraine is 155 units to 195 units administered intramuscularly (im) using a 30-gauge, 0.5 inch needle as 0.1 ml (5 units) injections to 31 and up to 39 sites. Injections should be divided across seven specific head/neck muscle areas. The recommended re-treatment schedule is every 12 weeks. Doses recommended for botulinum toxin type A (Botox ) are not interchangeable with other preparations of botulinum toxin. Botulinum toxin type A should only be administered by physicians with appropriate qualifications and expertise in the treatment and the use of the required equipment Product availability date July 2010 Summary of evidence on comparative efficacy Botulinum toxin type A, a purified neurotoxin complex derived from the bacterium Clostridium botulinum, blocks the release of neuromuscular transmitters. The presumed mechanism for headache prophylaxis is by blockade of peripheral signals to the central nervous system, which inhibits central sensitisation, as suggested by pre-clinical and clinical pharmacodynamic studies. The submitting company has requested that the Scottish Medicines Consortium (SMC) considers the use of botulinum toxin type A when positioned for use in patients with chronic migraine whose condition has failed to respond to 3 prior oral prophylactic treatments, where medication overuse has been appropriately managed and who are under the care of a headache specialist in a secondary care centre. The supporting evidence comes from two similarly designed, multi-centre, double-blind, placebo-controlled studies (PREEMPT 1 and 2) in adults with a history of chronic migraine meeting International Classification of Headache Disorders (ICHD-II) (2004) criteria. 1,2 During a 28-day baseline screening period patients were required to have 15 headache days with each day consisting of 4 hours of continuous headache and with 50% of days being migraine or probable migraine days, and 4 distinct headache episodes, each lasting 4 hours. The study had two phases, a 24-week double-blind, placebo-controlled phase with two injection cycles, followed by a 32-week open-label phase with three injection cycles. Eligible patients were randomised equally to botulinum toxin type A or placebo with stratification for frequency of acute headache pain medication intake during the 28-day baseline period (yes/no) and overuse of acute headache pain medications (defined as intake during baseline of simple analgesics on 15 days or other medication types or combination of types for 10 days, with intake 2 days/week from the category of overuse). Botulinum toxin type A (155 units) or placebo (sodium chloride 0.9%) was administered intramuscularly in 31 fixed-site, fixed-dose injections 2

3 across seven specific head/neck muscle areas. An additional 40 units could be administered at the investigator s discretion. All efficacy analyses used the intent-to-treat population, which included all randomised patients. In the PREEMPT 1 study, the primary endpoint was the mean change from baseline in frequency of headache episodes (defined as patient-reported headache with a start and stop time indicating that the pain lasted at least 4 continuous hours recorded in the patient diary) for the 28-day period ending with week In the PREEMPT 2 study, the primary endpoint was the mean change from baseline in frequency of headache days (defined as a calendar day when the patient reported four or more continuous hours of a headache, in the patient diary) for the 28- day period ending with week Botulinum toxin type A was significantly more effective than placebo for the primary endpoint in PREEMPT 2 only. Primary and key secondary endpoints for the two studies are included in the tables below. Table 1: PREEMPT 1, efficacy at week Efficacy Botulinum toxin Placebo variable type A (n=341) (n=338) Baseline Mean Baseline change Primary endpoint Headache episodes Mean change Difference (95% CI) p-value (-1.12 to 0.39) p=0.344 Secondary endpoints Headache days (-2.40 to -0.40) p=0.006 Migraine episodes (-1.21 to 0.26) p= Migraine days (-2.60 to -0.59) p=0.002 CI=confidence interval Table 2: PREEMPT 2, efficacy at week Efficacy Botulinum toxin Placebo variable type A (n=347) (N=358) Baseline Mean Baseline change Mean change Difference (95% CI) p-value Primary endpoint Headache days (-3.25 to -1.31) p<0.01 Secondary endpoints Headache episodes (-1.65 to -0.33) p=0.003 Migraine NR NR NR NR NR episodes Migraine days (-3.31 to -1.36) p< CI=confidence interval, NR=not reported There were no significant differences between groups in the frequency of acute headache pain medication consumption in either study, although there were significant differences in favour of botulinum toxin type A for reduction of triptan intake. 3

4 In the pooled analysis of the double-blind phase of the PREEMPT 1 and 2 studies, there was a significantly greater reduction in the mean change from baseline in the frequency of headache days in the botulinum toxin type A group compared with placebo (Table 3). 3 Post hoc subgroup analyses of this pooled analysis, which represents the target population proposed by the company, are also included in Table 3. Secondary endpoints that were significantly improved with botulinum toxin type A compared with placebo included: headache episodes (-5.2 versus -4.9) and Health-related quality of life (HRQL) measures, total Headache Impact Test-6 (HIT-6) score (mean change from baseline at week 24: versus -2.4) and changes in the three domains of the Migraine-Specific Quality of Life Questionnaire (preventive, restrictive and emotional). Table 3: Pooled analysis for the mean change from baseline in the frequency of headache days in PREEMPT 1 and 2, at week 24, 3 including subgroup analyses. Botulinum toxin Placebo Difference (95% CI) p-value ITT population for pooled analysis Mean change in headache days per 28 days n=688 n= (-2.52 to -1.13) p<0.01 During the open-label phase in which all patients received treatment with botulinum toxin type A at weeks 24, 36 and 48, the mean change in number of headache days fell in both groups; those who had previously received botulinum toxin type A and those who had previously received placebo. However, those patients who had received botulinum toxin type A from the start of the studies continued to improve more during the open-label phase, resulting in a significant difference between the two patient groups at one year. Discontinuation rates at the end of the double-blind phase were 12% versus 9.6% compared to 25% versus 29% at the end of the open-label phase in patients that were initially assigned to the botulinum toxin type A and placebo groups respectively. 4 In a published abstract of longer term follow up, 100 patients with chronic migraine treated with botulinum toxin type A as per the PREEMPT protocol who experienced a 50% reduction in headache frequency (days/month), relative to the baseline pre-treatment month ( responders ) continued treatment and were followed for two years (mean 2.9 years). Eight patients relapsed to chronic migraine. 24 patients discontinued treatment and remained largely free of headache for >6months. However, 68 patients remained responders but required ongoing treatment with throughout the study period. 5 Other data were also assessed but remain commercially confidential.* Summary of evidence on comparative safety There are limited safety data versus active comparators. In the pooled analysis the frequency of treatment-related adverse events was 29% in the botulinum toxin A group and 13% in the placebo group. There were 33 (4.8%) versus 16 (2.3%) serious adverse events and 26 (3.8%) versus 8 (1.2%) discontinuations related to adverse events, respectively. No deaths were reported. Adverse events with an incidence 5% were neck pain (6.7% versus 2.2%) and muscular weakness (5.5% versus 0.3%). No unexpected treatment related adverse events 4

5 were observed. 3 The Medicines and Healthcare products Regulatory Agency (MHRA) noted that the safety profile of botulinum toxin type A is well known and the incidence of adverse reactions of concern is low. 6 Summary of clinical effectiveness issues In pooled analysis of the two pivotal phase III studies, botulinum toxin type A significantly reduced the mean frequency of headache days compared with placebo. Although a number of treatments are recommended in guidelines for the prophylaxis of migraine, some have limited effectiveness and many are unlicensed for this indication. Limitations of the evidence include the primary outcome measure not being met in the PREEMPT 1 study, although at baseline there were significant differences between groups for headache episodes, migraine episodes and cumulative headache hours occurring on headache days. The primary outcome in the PREEMPT 2 study was changed to frequency of headache days prior to the study s completion and treatment unmasking. The mean change in frequency of headache days was met in PREEMPT 2 and in a pooled analysis of the two studies. The MHRA was satisfied with the consistency of the results between the endpoints for both trials. 4 There was a high placebo response in both studies which could not fully be accounted for and there was no test that study blinding had been maintained. Both studies allowed patients who had overused acute migraine medication to be recruited which accounted for approximately two-thirds of patients overall. As the International Classification of Headache Disorders, 2 nd edition, (ICHD-II) (2006) excludes patients who overuse acute medication in a diagnosis of chronic migraine, 7 the study population may therefore not reflect the population of patients who would currently be diagnosed with chronic migraine. However randomisation in the studies was stratified for this variable and analysis of the headache days endpoint in the sub-group of patients who overused acute medication at enrolment (n=904 in the pooled population) resulted in a similar outcome to that of the total population. There are limited efficacy data in males, who accounted for only 14% of the phase III study population. The SPC notes that the treatment effect appeared smaller in the subgroup of male patients (N=188) than in the whole study population. 8 A significant proportion of patients recruited to the PREEMPT 1 and 2 studies had received no previous prophylactic medication. In this resubmission, the submitting company has requested that the Scottish Medicines Consortium (SMC) considers the use of botulinum toxin type A when positioned for use in patients with chronic migraine whose condition has failed to respond to 3 prior oral prophylactic treatments, where medication overuse has been appropriately managed and who are under the care of a headache specialist in a secondary care centre. Post-hoc sub-group analysis of PREEMPT 1 and 2 study data and a proxy population supports efficacy in the proposed target population. There was no stratification in the study design for the patients treated with at least three previous prophylactic medications, however previous prophylactic medication for each patient was recorded in the case report form. As a sensitivity analysis and to support this re-analysis of the data, patients previously treated with topiramate, were used as a proxy for the target population, using the assumption that topiramate as a second line treatment after beta-blockers and amitriptyline would approximate to patients previously treated with at least three previous prophylactic therapies. 5

6 There are no comparative data against other recommended prophylactic migraine treatments. The submitting company has proposed that best supportive care is the most relevant comparator when botulinum toxin type A is positioned after the use of 3 prior oral prophylactic treatments. The British Association for the Study of Headache (BASH) guidelines 2010 provide recommendations for first, second and third line treatments in migraine prophylaxis. 7 Comparing use of botulinum toxin type A against best supportive care after at least three other oral treatments does not seem unreasonable. Quality of life as measured by three tools, including one migraine specific measure, and was significantly improved for botulinum toxin type A patients compared with placebo patients. Botulinum toxin type A injections require to be administered by appropriately trained personnel in hospital specialist centres. This may have significant implications for service delivery due to the potential number of eligible patients as well as for the patient. The decision to treat with botulinum toxin type A may require additional consultation time and additional time and resource to administer the treatment. The company has proposed a negative stopping rule; treatment would be stopped when patients have failed to achieve a 30% reduction in headache days per month. A positive stopping rule is also proposed whereby patients may cease treatment when it may no longer be required. This positive stopping rule is likely to require continued specialist consultation both for a decision to cease, continue or re-introduce treatment on relapse. At present there is no evidence to support this positive stopping rule but a single study reporting longer term use of botulinum toxin type A injections would suggest that only a small number of patients are likely to have treatment discontinued. Successful use of this prophylactic treatment may lead to a reduction in acute medication intake and result in episodic rather than chronic migraine. Summary of comparative health economic evidence The submitting company provided a cost-utility analysis comparing botulinum toxin type A injections, given every 12 weeks, to best supportive care in a population of patients experiencing chronic migraine, who have previously failed on >3 prophylactic therapies, where medication overuse has been appropriately managed and who are in the care of a headache specialist in a secondary care centre. Best supportive care was assumed to encompass treatments including use of off-label medicines such as gabapentin, venlafaxine and interventional procedures, for example, greater occipital nerve blocks. Alternatively, patients in the model may not be given a prophylactic treatment and be managed by acute treatments only. Negative and positive stopping rules for botulinum toxin type A were incorporated into the model. After discussion with clinicians, the submitting company assumed that if a patient was in the same or a worse health state at 24 weeks, treatment would be discontinued due to nonresponse. Treatment also ceased at one year for a proportion of successfully treated patients (those moving from chronic to episodic migraine). A two year time horizon was used for the analysis. Effectiveness data for the model were taken from patient level data from the post hoc pooled analysis of the key studies. The mean headache days over a 28 day period was used to 6

7 categorise patients into health states in the model. Best supportive care was assumed to be as effective as the placebo saline solution injections arm of the key studies. Clinical study data were available for up to one year for botulinum toxin type A treated patients. Thereafter, it was assumed that the transition probabilities came from the clinical studies for patients with three or more treatments: the active arm used a combination of 24-36, and week movements of the relevant patients; and The modelled placebo arm used week movements. The submitting company estimated EQ-5D values by transforming the Migraine Specific Questionnaire (MSQ) scores collected in the clinical studies. A regression analysis was developed from the patient level EQ-5D and MSQ values collected in the International Burden of Migraine Study (IBMS) study and applied to the MSQ data from the studies. Medicine acquisition costs for botulinum toxin type A plus associated administration costs were incorporated into the analysis. Administration was assumed to take 15 minutes of time from a specialist nurse in an outpatient setting. No medication costs were assumed for the comparator arm of the model, despite the assumption that these would be used as part of best supportive care. This is a therefore a conservative assumption. Patients in the best supportive care arm were however assumed to have a consultant neurologist visit every 12 weeks. Other resource use, including GP visits, A&E and hospitalisation, relating to acute episodes was estimated from the International Burden of Migraine Study. These data may not generalise to a Scottish setting. The base case incremental cost per quality adjusted life year (QALY) was 12,176 based on an incremental cost of 1,012 and a QALY gain of Substituting the Information Services Division s (ISD) published cost for outpatient appointments of 206 for a consultant neurologist and 67 for a nurse outpatient increased the cost per QALY to 14,915. This may have been a more appropriate base case cost per QALY ratio. Sensitivity analyses showed that the results were sensitive to the assumed transitional probabilities, changes in utility values, the time horizon, the stopping criteria and cost of botulinum toxin type A and its administration. The results were most sensitive to the assumed health states for those who discontinue botulinum toxin type A at one year because of good response. The base case assumed these people would remain in the same health state as occupied at end of year 1. If however these people respond as per the BSC arm the cost/qaly increased to over 20,100. With a one year time horizon the incremental cost effectiveness ratio (ICER) was 19,152. For 10 and 20 years time horizons, the ICERS were about 15,350 (26% higher). In these scenarios, episodic patients who discontinue after one year were assumed to have placebo efficacy and utility values. Applying the positive stopping criteria requires that, at the end of the first year, people who benefit from the treatment, being those who have moved from chronic to episodic migraines, cease the treatment. With no positive stopping rule the baseline cost per QALY increased from 12,176 to 16,873, almost a 40% increase. If there was no negative stopping rule, the cost per QALY rose to 16,184. SMC clinical experts have given mixed views as to the feasibility of such a rule in Scottish clinical practice. 7

8 The results were not unduly sensitive to resources use. A sensitivity analysis assumed patients attended four outpatient consultations over two years, compared to eight in the base case; and that the only resource saving was seven triptan-based doses a month to treat the migraines. The resulting cost/qaly was 14,671, an increase of about 2,500 (20%) from the original base case. There were a number of limitations associated with the analysis: The clinical data underpinning the model were based on a post hoc subgroup analysis comprising about one third of the pooled study population, and limitations with this data are noted above. There is uncertainty about the feasibility of applying both the positive and negative stopping criteria in clinical practice, and the results were particularly sensitive to this aspect. There is uncertainty in relation to the comparator effectiveness which is assumed to be the same as the placebo response rate in the pooled analysis. However, sensitivity analysis reported that if BSC reduced the number of headache days a month by one more than placebo then the ICER rose to 13,160. Resource costs underestimated the cost of outpatient appointments. Applying the published ISD cost for relevant outpatient appointments increased the cost /QALY to 14,915. There is uncertainty regarding the continued efficacy of treatment and the results of the analysis were sensitive to the assumed time horizon. There is uncertainty about the optimal duration of treatment. No training costs were included which may not be appropriate given this is a new treatment modality. However, additional sensitivity analysis was provided which indicated that the results were not sensitive to the addition of some staff time for training. Any costs of providing a new service are also excluded. While the base case cost per QALY ratio was not unduly high, it was clear from the range of one-way sensitivity analyses presented that there was upward uncertainty associated with several of the inputs to the analysis, which if they had been combined, would be likely to cause the cost per QALY to rise further. Given the uncertainty around this, the economic case was not demonstrated. Summary of patient and public involvement Patient Interest Group submissions were received from: Migraine Action The Migraine Trust Additional information: guidelines and protocols The Scottish Intercollegiate Guideline Network (SIGN) published; Diagnosis and management of headache in adults, a national clinical guideline (no. 107) in November Propranolol is recommended for first-line use for migraine prophylaxis and timolol, atenolol, nadolol and metoprolol can be used as alternatives to propranolol. Topiramate, gabapentin, amitriptyline or venlafaxine are alternative treatment options. Botulinum toxin type A is not recommended for the prophylactic treatment of migraine. Need for updating being considered. 9 8

9 The National Institute of Health and Clinical Excellence Clinical Guideline (NICECG) 150: Headaches. Diagnosis and management of headaches in young people and adults. September This guideline provides guidance on the assessment, diagnosis and management of all types of headache. For prophylaxis of migraine after discussion with the patient: offer topiramate or propranolol according to comorbidities and risk of adverse events. If both topiramate and propranolol are unsuitable or ineffective, consider a course of up to 10 sessions of acupuncture over 5 8 weeks or gabapentin (up to 1200 mg per day) according to preference, comorbidities and risk of adverse events. For people who are already having treatment with another form of prophylaxis such as amitriptyline, and whose migraine is well controlled, continue the current treatment as required. Review the need for continuing migraine prophylaxis 6 months after the start of prophylactic treatment. Advise people with migraine that riboflavin (400 mg once a day) may be effective in reducing migraine frequency and intensity for some people. 10 The British Association for Study of Headache (BASH) published Guidelines for All Healthcare Professionals in the Diagnosis and Management of Migraine, Tension-Type, Cluster and Medication-Overuse Headache (3 rd edition, 1 st revisions) in January The following recommendations are based on this evidence coupled with expert clinical experience. First-line prophylactic drugs include beta-adrenergic blockers without partial agonism (atenolol, metoprolol, propranolol or bisoprolol) or amitriptyline. Second-line prophylactic drugs include topiramate or sodium valproate. Third-line prophylactic drugs include gabapentin or methysergide. The guidelines note that: botulinum toxin type A is licensed for prophylaxis of patients with more than 15 headache days per month, of which at least eight days are with migraine. The difference between active and placebo treatments was small in reported clinical trials, although statistically significant. 7 Additional information: comparators There are a number of treatments recommended in treatment guidelines for the prophylaxis of migraine, many of which are unlicensed (off-label) in this indication. However, most guidelines only recommend up to three lines of treatment. 9

10 Cost of relevant comparators Drug Dose Regimen Cost per year ( ) Cost per course ( ) Botulinum toxin type A (Botox ) Gabapentin* 155 to 195 units intramuscularly every 12 weeks. 1,200mg to 2,400mg orally to 302 per day Topiramate 50mg to 200mg orally per day 22 to 85 Venlafaxine* 75 to 150mg orally per day 20 to 40 Propranolol 80mg to 240mg orally per day 14 to 45 Amitriptyline* 25mg to 150mg orally per day 11 to 36 Doses are for general comparison and do not imply therapeutic equivalence. Costs from evadis and MIMS on 14 Jan. The cost of botulinum toxin type A is based on 5 treatments. The dose regimens for comparators are taken from the SIGN 107 guideline (and may be higher than SPC recommendations), and are used *off-label for gabapentin, amtriptyline and venlafaxine. Additional information: budget impact The submitting company estimated the population eligible for treatment to be 4,700 in year 1 rising to 4,803 in year five with an estimated uptake rate of 2.5% in year 1 and 7.00% in year 5. The gross impact on the medicines budget was estimated to be 108k in year 1 and 308k in year 5. As no other drugs were assumed to be displaced the net medicines budget impact is expected to remain as 108k in year 1 and 308k in year 5. SMC clinical experts advised that there would be significant service implications associated with the introduction of this treatment for chronic migraine. 10

11 References The undernoted references were supplied with the submission. Those shaded in grey are additional to those supplied with the submission. 1. Aurora SK, Dodick DW, Turkel CC, et al. OnabotulinumtoxinA for treatment of chronic migraine: results from the double-blind, randomized, placebo-controlled phase of the PREEMPT 1 trial. Cephalalgia Jul;30(7): Diener HC, Dodick DW, Aurora SK, et al. OnabotulinumtoxinA for treatment of chronic migraine: results from the double-blind, randomized, placebo-controlled phase of the PREEMPT 2 trial. Cephalalgia Jul;30(7): Dodick DW, Turkel CC, Degryse RE, et al. OnabotulinumtoxinA for Treatment of Chronic Migraine: Pooled Results From the Double-Blind, Randomized, Placebo-Controlled Phases of the PREEMPT Clinical Program. Headache Jun;50(6): Aurora SK, Winner P, Freeman MC et al. OnabotulinumtoxinA for Treatment of Chronic Migraine: Pooled Analysis of the 56-week PREEMPT Clinical Program. Headache. 2011;51: Rothrock JF, Andress-Rothrock D, Scanlon C, Weibelt S. OnabotulinumtoxinA for the treatment of chronic migraine: Long-term outcome. American Headache Society 53rd Annual Scientific Meeting. Washington DC (USA), Medicines and Healthcare Products Regulatory Agency (MHRA) UK Product Assessment Report (UKPAR) botulinum toxin type A (Botox ). 7. MacGregor EA, Steiner TJ, Davies PTG. Guidelines for all healthcare professionals in the diagnosis and management of migraine, tension-type, cluster and medication-overuse headache. British Association for the Study of Headache. 3 rd Edition (1 st revision) Allergen Ltd. Summary of Product Characteristics for botulinum toxin type A (Botox ). Last updated 04 October Scottish Intercollegiate Guidelines Network. Diagnosis and management of headache in adults: A national clinical guideline. Guideline No. 107; The National Institute of Health and Clinical Excellence Clinical Guideline (NICECG) 150: Headaches. Diagnosis and management of headaches in young people and adults. September This assessment is based on data submitted by the applicant company up to and including 15 February *Agreement between the Association of the British Pharmaceutical Industry (ABPI) and the SMC on guidelines for the release of company data into the public domain during a health technology appraisal: Drug prices are those available at the time the papers were issued to SMC for consideration. These have been confirmed from the evadis drug database. SMC is aware that for some hospital-only products national or local contracts may be in place for comparator products that can significantly reduce the acquisition cost to Health Boards. These contract prices are commercial in confidence and cannot be put in the public domain, including via the SMC Detailed Advice Document. Area Drug and Therapeutics Committees and NHS Boards are therefore asked to consider contract pricing when reviewing advice on medicines accepted by SMC. 11

12 Advice context: No part of this advice may be used without the whole of the advice being quoted in full. This advice represents the view of the Scottish Medicines Consortium and was arrived at after careful consideration and evaluation of the available evidence. It is provided to inform the considerations of Area Drug & Therapeutics Committees and NHS Boards in Scotland in determining medicines for local use or local formulary inclusion. This advice does not override the individual responsibility of health professionals to make decisions in the exercise of their clinical judgement in the circumstances of the individual patient, in consultation with the patient and/or guardian or carer. 12