Table 1.

Schedule of enrolment, interventions and assessments (SPIRIT)

TIMEPOINT	STUDY PERIOD
	Screening	Baseline/ treatment	Treatment period			End of study	Safety registration
	Within 6 weeks before baseline	Day 0	Day 14	Day 42	Day 98	Day 154	Day 278
ENROLMENT:
Eligibility screen	X
Informed consent	X
Medical history	X
MRI-scana	X					X
Chest X-ray	X
Urine pregnancy testb	X	X		X	X	X
Blood samples (hematology, clinical chemistry, CRP)c	X	X	X	X	X	X
TB, Hep C, Hep B-screening	X
Allocation		X
INTERVENTION:
Infliximab		X	X	X	X
Placebo		X	X	X	X
ASSESSMENTS:
Background datad	X	X
Clinical safety evaluatione	X	X	X	X	X	X
Clinical pain/neuro evaluationf	X
Blood samples for drug concentrations and antibodiesg		X	X	X	X	X
Blood samples for biobank		X			X	X
Adverse events			X	X	X	X	X
Primary outcomeh		X	X	X	X		X
Pain monitoringi		X	X	X	X	X	X
Concomitant medication	X	X	X	X	X	X	X
Co-interventions (non-pharm)	X	X	X	X	X	X	X
Sick listing		X			X	X	X
Questionnairesj		X			X	X
Compliancek		X	X	X	X

^aBaseline MRI according to the study protocol can be maximum 4 weeks old when treatment starts. A follow-up MRI is taken between 6 and 7 months after treatment start (i.e. 7 to 8 months after baseline MRI).

^bUrine pregnancy test will be performed at screening and monthly from treatment initiation until 9 months. Results will be enquired with telephone follow up.

^cHaematological parameters (hemoglobin, haematocrit (hct), erythrocytes, white blood cells with differentials, platelet counts), Clinical chemistry (AST and/or ALT, ALP, albumine, creatinine, random glucose, potassium, sodium) and CRP (SLV-imposed). Random glucose is for further safety monitoring (self-imposed)

^dBaseline data

^eWeight, blood pressure, pulse, auscultation of hearth and lunges, GI and neurological examination

^fPain provocation tests, neurological tests

^gAntibodies to infliximab

^hODI

ⁱPain-monitoring (LBP intensity) weekly during follow-up period

^jEQ 5D-5L,RMDQ, Patients’satisfaction, global perceived effect, symptom specific well-being, leg pain intensity, hours with LBP last 4 weeks

^kNumber of completed intravenous infusions with the IMP