An Economic Comparison of Treatment Strategies with Anakinra in Systemic Juvenile Idiopathic Arthritis (sJIA)

Figures & data

Table 1 Economic Analysis Input Parameters

Input	Value	Reference
Clinical parameters (first-line anakinra) These parameters are used to establish which proportion of patients have CAD versus CID over the time frame of the economic analysis, for patients managed with first-line anakinra.
CID at 1 year	76%	ter Haar et al.^Citation21
CID at 3 years	94%
CID at 5 years	96%
CID off treatment at 1 year	52%
CID off treatment at 3 years	71%
CID off treatment at 5 years	72%
Clinical parameters (later-line anakinra) These parameters are used to establish which proportion of patients have CAD versus CID over the time frame of the economic analysis, for patients managed with later-line anakinra. A multitude of sources is used for this treatment strategy, owing to a lack of data available specifically reporting on the experience of sJIA patients managed with later-line anakinra following initial treatment with NSAIDs and csDMARDs.
Monocyclic course	25.5%	Grevich and Shenoi^Citation33
CID w/ corticosteroids (monocyclic)	30% (in 6 weeks)	Assumption
CID w/ methotrexate (monocyclic)	20% (in 24 weeks)	Assumption based on Nordström et al.^Citation17
CID w/ corticosteroids (chronic)	0%	Assumption
CID w/ methotrexate (chronic)	0%	Assumption
CID w/ bDMARDs	50% (in 24 weeks)	Assumption based on Nordström et al.^Citation17
Discontinuation for NSAIDs + corticosteroids	95% off by 6 weeks	Assumption
Discontinuation for csDMARD ± NSAIDs + corticosteroids	95% off by 16 weeks	Assumption
Discontinuation for bDMARDs	12.6% per year	NICE TA238^Citation30
Proportion on bDMARDs with CID	50%	Assumption
CID at 5 years	78%	Calculation based on input parameters above
Difference in CID at 5 years	18%
Drug costs per week These parameters are used to inform drug acquisition cost results. These costs refer to the estimated cost per week.
NSAIDs + corticosteroids	€ 0.82	Z-Index B.V.^Citation35
csDMARD	€ 18.88
Anakinra	€ 225.40
Tocilizumab	€ 275.68
Annual medical resource use These parameters are used to estimate the medical resource utilization associated with patients that have CAD versus CID, noting that in general patients with CAD require additional resource.
Rheumatology (CAD)	12.0	NICE TA238.^Citation30 For rheumatology, increased from 10 reported in NICE TA238 to 12 reflecting an average of 1 appointment per month
Hematology (CAD)	12.0
GP (CAD)	20.8
Hospitalization (CAD)	22.1
Rheumatology (CID)	4.0	Assumed 1 appointment every 3 months
GP (CID, on treatment)	3.5	NICE TA238^Citation30
GP (CID, off treatment)	0.0	Assumption
Unit costs for medical resource use These parameters are used to assign costs based on the expected frequency of use (separated by CAD versus CID, as shown in the preceding rows).
Rheumatology or hematology	€ 101.00	iMTA costing tool:^Citation34 Outpatient visit, pediatrics
GP	€ 33.00	iMTA costing tool:^Citation34 General practitioner, standard consultation
Hospitalization	€ 642.00	iMTA costing tool:^Citation34 Nursing day, academic hospital

Abbreviations: bDMARD, biologic disease-modifying anti-rheumatic drug; csDMARD, conventional synthetic disease-modifying anti-rheumatic drug; CAD, clinically-active disease; CID, clinically-inactive disease; GP, General practitioner; iMTA, Institute for Medical Technology Assessment; NICE, National Institute for Health and Care Excellence; NSAID, non-steroidal anti-inflammatory drug; TA, technology appraisal.

Figure 1 Base-case analysis results.

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