Cost-utility and Physiological Effects of LDN in Patients With Fibromyalgia
Status:
Not yet recruiting
Trial end date:
2024-07-31
Target enrollment:
Participant gender:
Summary
Background: Low-dose naltrexone (LDN) may be useful in managing the pathologies that alter
inflammatory markers, such as Crohn's disease or fibromyalgia (FM). The anti-inflammatory
effect of LDN should be produced through the inhibition of Toll-like receptor 4 activity
expressed in the membrane of various immune system cells (e.g. microglia). Conversely, due to
a rebound effect, LDN could exercise an analgesic effect that strengthens the endogenous
inhibitory system. According to this hypothesis, the low-intensity and intermittent blocking
of the opioid receptors generated by LDN should induce a compensatory mechanism that should
facilitate an increase in the production of endogenous opioids and greater sensitivity of the
system to their effects. To date, the effects of LDN in patients with FM have been evaluated
through crossover studies that have yielded promising results. Given that the studies
conducted up to now have had small sample sizes and crossover designs, and given that there
are still no studies in which its potential cost-utility is assessed, studies with greater
methodological rigor and larger samples are necessary to confirm the effectiveness of LDN in
FM.
Jointly evaluating the effectiveness and cost-utility, the changes in metabolites in certain
areas of the brain, and systemic inflammatory markers potentially linked to the
etiopathogenesis of FM, should allow us to gain a more detailed knowledge of the
neurobiological mechanisms underlying the effectiveness of LDN in this population.
Objectives: To evaluate the effectiveness and safety of LDN in patients with FM and analyse
its cost-utility both from the government and the healthcare perspective at 1-year follow-up.
Brain metabolites and systemic inflammatory biomarkers will be included to evaluate
neurobiological mechanisms behind LDN therapeutic effects.
Design: Randomized, Controlled Trial. Centre: Parc Sanitari Sant Joan de Déu (St. Boi de
Llobregat, Spain). Participants: 120 patients with FM will be randomly assigned to LDN
(4.5mg/day) or placebo.
Main outcome measure: Pain severity using Ecological Momentary Assessment. Secondary
outcomes: functionality, affective symptoms, fibrofog, quality of life. Costs and QALYs will
be also calculated. Biomarkers: 50% of the patients will be scanned at baseline and at week
12 for changes in brain metabolites related to neuroinflammation and central sensitization.
Immune-inflammatory markers in serum will also be evaluated.