AbobotulinumtoxinA in the management of cervical dystonia in the United Kingdom: a budget impact analysis

Figures & data

Table 1 Prevalence of CD

Disease	Base case value	Range	Reference
CD
Total population with CD	13,324	3,631–23,571	Erjanti et al^Citation20 Epidemiological Study of Dystonia in Europe (ESDE) Collaborative Group^Citation6 Ipsen Biopharm Ltd, unpublished data, 2012
Percentage of patients with CD receiving care with BoNT-A	80.0%	Not applicable	Ipsen Biopharm Ltd, unpublished data, 2012

Abbreviations: CD, cervical dystonia; BoNT-A, botulinum neurotoxin A.

Table 2 Market share and absolute number of patients receiving BoNT-A

Scenarios	BoNT-A treatment	Year 1		Year 2		Year 3		Year 4		Year 5
		Proportion of patients eligible (%)	Number of patients eligible	Proportion of patients eligible (%)	Number of patients eligible	Proportion of patients eligible (%)	Number of patients eligible	Proportion of patients eligible (%)	Number of patients eligible	Proportion of patients eligible (%)	Number of patients eligible
Status quo	AbobotulinumtoxinA	69	7,525	69	7,601	69	7,678	69	7,756	69	7,834
	OnabotulinumtoxinA	15.5	1,690	15.5	1,708	15.5	1,725	15.5	1,742	15.5	1,760
	IncobotulinumtoxinA	15.5	1,690	15.5	1,708	15.5	1,725	15.5	1,742	15.5	1,760
Total		100	10,906	100	11,016	100	11,128	100	11,240	100	11,353
New projections	AbobotulinumtoxinA	69	7,525	72	7,932	75	8,346	78	8,767	81	9,196
	OnabotulinumtoxinA	15.5	1,690	14	1,542	12.5	1,391	11	1,236	9.5	1,079
	IncobotulinumtoxinA	15.5	1,690	14	1,542	12.5	1,391	11	1,236	9.5	1,079
Total		100	10,906	100	11,016	100	11,128	100	11,240	100	11,353

Abbreviation: BoNT-A, botulinum neurotoxin A.

Table 3 BoNT-A medication treatment cost and dosage

BoNT-A	Base case value	Range		Source
		Minimum	Maximum
AbobotulinumtoxinA
Vial cost of abobotulinumtoxinA (300 units)	£92.40	£73.92	£110.88	British National Formulary;^Citation18 range for costs were assumed at ±20%
Vial cost of abobotulinumtoxinA (500 units)	£154.00	£123.20	£184.80	British National Formulary;^Citation18 range for costs were assumed at ±20%
Dosage per injection of abobotulinumtoxinA	500 units	500 units	1000 units	SPC;^Citation22 range informed by clinical expert opinion
Reinjection interval for abobotulinumtoxinA	12 weeks	12 weeks	12 weeks	SPC;^Citation22 range informed by clinical expert opinion
OnabotulinumtoxinA
Vial cost of onabotulinumtoxinA (50 units)	£77.50	£62.00	£93.00	British National Formulary;^Citation18 range for costs were assumed at ±20%
Vial cost of onabotulinumtoxinA (100 units)	£138.20	£110.56	£165.84	British National Formulary;^Citation18 range for costs wereassumed at ±20%
Vial cost of onabotulinumtoxinA(200 units)	£276.40	£221.12	£331.68	British National Formulary;^Citation18 range for costs wereassumed at ±20%
Dosage per injection of onabotulinumtoxinA	200 units	200 units	300 units	SPC;^Citation23 range informed by clinical expert opinion
Reinjection interval for onabotulinumtoxinA	12 weeks	10 weeks	12 weeks	SPC;^Citation23 range informed by clinical expert opinion
IncobotulinumtoxinA
Vial cost of incobotulinumtoxinA(50 units)	£72.00	£57.60	£86.40	British National Formulary;^Citation18 range for costs wereassumed at ±20%
Vial cost of incobotulinumtoxinA(100 units)	£129.90	£103.92	£155.88	British National Formulary;^Citation18 range for costs wereassumed at ±20%
Dosage per injection of incobotulinumtoxinA	200 units	200 units	300 units	SPC;^Citation24 range informed by clinical expert opinion
Reinjection interval for incobotulinumtoxinA	10 weeks	10 weeks	12 weeks	SPC;^Citation24 range informed by clinical expert opinion

Abbreviations: BoNT-A, botulinum neurotoxin A; SPC, summary of product characteristics.

Table 4 Resource use for BoNT-A and best supportive care (without BoNT-A) arms in the base case

Resource use item	BoNT-A arm, % using	BoNT-A arm, amount	BSC arm, % using	BSC arm, amount	Sources
Concomitant medication
Anticholinergics	0.6	1 mg daily dose	5	1 mg daily dose	UK clinical expert opinion;British National Formulary^Citation18
Clonazepam	26.5	1 mg daily dose	26.5	1 mg daily dose	UK clinical expert opinion;British National Formulary^Citation18
Analgesics	33.5	1 g daily dose	33.5	1 g daily dose	UK clinical expert opinion;British National Formulary^Citation18
Dopamine antagonist	0	NA	5	2.5 mg daily dose	UK clinical expert opinion;British National Formulary^Citation18
Beta-blockers	0	NA	0.6	40 mg daily dose	UK clinical expert opinion;British National Formulary^Citation18
Baclofen	0	NA	3.2	60 mg daily dose	UK clinical expert opinion;British National Formulary^Citation18
Antiepileptics	0	NA	5.8	600 mg daily dose	UK clinical expert opinion;British National Formulary^Citation18
Other muscle relaxants	0	NA	22.6	7.5 mg daily dose	UK clinical expert opinion;British National Formulary^Citation18
Health care professional
Neurologist visit (for injection)	73.5	4.33 visits per yeara	0	NA	UK clinical expert opinion
Neurophysiologist visit (for injection)	26.5	4.3 visits per yeara	0	NA	UK clinical expert opinion
Neurologist visit (excluding injections)	0	NA	100	2 visits per year	UK clinical expert opinion
GP visit	100	2 visits per year	100	2 visits per year	UK clinical expert opinion
Hospitalization	1.5	1 visit per year	1.5	1 visit per year	UK clinical expert opinion
Laboratory test
Blood test	0	0	10	4 times per year	UK clinical expert opinion
Procedures
EMG with needle	5	4.33 times per yeara	0	NA	UK clinical expert opinion
Deep brain stimulation	0	NA	1	1 time per year	UK clinical expert opinion
Selective peripheral denervation	0	NA	1	1 time per year	UK clinical expert opinion

Note:

a Frequency of resource use is linked to reinjection interval.

Abbreviations: BoNT-A, botulinum neurotoxin A; BSC, best supportive care; NA, not available; GP, general practitioner; EMG, electromyography; UK, United Kingdom.

Table 5 BoNT-A medication dosage for “real-world” settings

BoNT-A	Mean	Source
AbobotulinumtoxinA
Dosage per injection ofabobotulinumtoxinA	448 units	Hubble et al^Citation27
Reinjection interval forabobotulinumtoxinA	11 weeks	Clinical expert opinion
OnabotulinumtoxinA
Dosage per injection ofonabotulinumtoxinA	142 units	Marchetti et al^Citation28
Reinjection interval foronabotulinumtoxinA	11 weeks	Clinical expert opinion
IncobotulinumtoxinA
Dosage per injection ofincobotulinumtoxinA	200 units	Misra et al^Citation29
Reinjection interval forincobotulinumtoxinA	10 weeks	Clinical expert opinion

Abbreviation: BoNT-A, botulinum neurotoxin A.

Table 6 Net 5-year budget impact of increasing abobotulinumtoxinA market share compared to status quo assumptions in the treatment of cervical dystonia in the UK

	Year 1 (£)	Year 2 (£)	Year 3 (£)	Year 4 (£)	Year 5 (£)	Total (£)
Budget under status quo assumptions	19,991,484	20,193,298	20,397,149	20,603,059	20,811,047	101,996,037
Budget under new market share assumptions	19,991,484	19,972,687	19,951,473	19,927,795	19,901,606	99,745,045
Net budget impact	0	–220,611	–445,677	–675,264	–909,441	–2,250,992

Figure 1 Cost of BoNT-A and best supportive care per patient per year by cost component.

Abbreviation: BoNT-A, botulinum neurotoxin A.

Figure 2 Tornado diagram of one-way sensitivity analysis showing the parameters that are most influential on net budget impact.

Table 7 Variable description for tornado diagram

Variable	Variable description
Time_Dysport	Time to reinjection of abobotulinumtoxinA
NumVisY_D_NeurInj	Number of visits per year – neurologist(for injection) on abobotulinumtoxinA arm
Time_Botox	Time to reinjection of onabotulinumtoxinA
Dose_Dysport	Dosage per injection of abobotulinumtoxinA
Dose_Botox	Dosage per injection of onabotulinumtoxinA
Dose_Xeomin	Dosage per injection of incobotulinumtoxinA
CDPrev	Prevalence of cervical dystonia
VialC_Xeomin100	Vial cost of incobotulinumtoxinA (100 units)
VialC_Dysport500	Vial cost of abobotulinumtoxinA (500 units)
Time_Xeomin	Time to reinjection of incobotulinumtoxinA
VialC_Botox200	Vial cost of onabotulinumtoxinA (200 units)
CDTrt	Percentage of cervical dystonia patientswho receive care
NumVisY_D_Physio	Number of visits per year – neurophysiologiston abobotulinumtoxinA arm
PropUt_D_NeurInj	Proportion utilizing neurologist (for injection)on abobotulinumtoxinA arm
UnitC_D_NeurInj	Unit cost – neurologist (for injection) onabobotulinumtoxinA arm

ErjantiHMarttilaRRinneUThe prevalence and incidence of cervical dystonia in south-western FinlandMov Disord199611Suppl 1A215

 Google Scholar

Epidemiological Study of Dystonia in Europe (ESDE) Collaborative GroupA prevalence study of primary dystonia in eight European countriesJ Neurol20002471078779211127535

 PubMed Web of Science ®Google Scholar

British National Formulary [webpage on the Internet]Joint Formulary CommitteeBritish National Formulary2012 Available from: https://www.medicinescomplete.com/mc/bnf/current/Accessed December 14, 2012

 Google Scholar

MHRADysport Powder for Solution for Injection and Botulinum Toxin Type A Powder for Solution for Injection (Clostridium botulinum Type A Toxin – Haemagglutinin Complex). PL 34926/0014 and 0015Slough, UKUKPAR2011 Available from: http://www.mhra.gov.uk/home/groups/par/documents/websiteresources/con108612.pdfAccessed July 22, 2014

 Google Scholar

MHRABotox (Botulinum Toxin Type A). PL 00426/0074-0110, PL 00426/0118-0030, PL 00426/0119-0012Slough, UKUKPAR2012 Available from: http://www.mhra.gov.uk/home/groups/par/documents/websiteresources/con208720.pdfAccessed July 22, 2014

 Google Scholar

MHRAXeomin 100 LD50 Units Powder for Solution for InjectionSlough, UKUKPAR2012 Available from: http://www.mhra.gov.uk/home/groups/spcpil/documents/spcpil/con1427432040685.pdfAccessed July 22, 2014

 Google Scholar

HubbleJSchwabJHubertCAbbottCCDysport (botulinum toxin type A) in routine therapeutic usage: a telephone needs assessment survey of European physicians to evaluate current awareness and adherence to product labeling changesClin Neuropharmacol201336412212723783005

 PubMed Web of Science ®Google Scholar

MarchettiAMagarRFindleyLRetrospective evaluation of the dose of Dysport and BOTOX in the management of cervical dystonia and blepharospasm: the REAL DOSE studyMov Disord200520893794415810022

 PubMed Web of Science ®Google Scholar

MisraVPEhlerEZakineBMaisonobePSimonetta-MoreauMINTEREST IN CD groupFactors influencing response to Botulinum toxin type A in patients with idiopathic cervical dystonia: results from an international observational studyBMJ Open201223piie000881

 Web of Science ®Google Scholar