Low-dose naltrexone for the treatment of fibromyalgia: protocol for a double-blind, randomized, placebo-controlled trial

Table 1 Schedule of enrolment, interventions, and assessments

	Study period
	Enrolment	Allocation	Post-allocation				Follow-up
Week	*−4–0*	0	2^a *(telephone)*	4^a	8^b	12^b	16^b
Enrolment
Informed consent	X
Medication history	X	X	X	X	X	X	X
Demographic data	X
Eligibility screen	X
Allocation		X
Interventions
Low-dose naltrexone
Placebo
Assessments
Vital tests: blood pressure, weight, height		X				X	X
Safety tests: ALAT, creatinine, GFR, thrombocyte count, bilirubin. ECG	X					X
hCRP		X
Blood for biobank		X				X
PROMs
PHQ-9	X
GAD-7	X
FIQR		X		X	X	X	X
PGI-C				X	X	X	X
EQ-5D		X		X	X	X	X
EQ-VAS		X		X	X	X	X
Pain sensitivity
Handheld algometry		X				X
Computerized cuff algometry		X				X
Muscle tests
Isometric muscle exhaustion of deltoid		X				X
30-s stand chair test		X				X
Compliance assessment						X
Adverse events		X	X	X	X	X	X

ALAT alanine aminotransferase, GFR glomerular filtration rate, ECG electrocardiogram, PHQ-9 Patient Health Questionnaire – 9 items, GAD-7 Generalized Anxiety Disorder – 7 items, hCRP high-sensitive C-reactive protein, FIQR Fibromyalgia Impact Questionnaire Revised, PGI-C Patient Global Impression of Change, EQ-5D EuroQol 5 dimensions, EQ-VAS EuroQol Visual Analogue Scale
^a±2 days
^b±7 days

ISSN: 1745-6215