mycophenolic-acid and Complex-Regional-Pain-Syndromes

Current therapies for persistent complex regional pain syndrome (CRPS) are grossly inadequate. With accruing evidence to support an underlying immunological process and anecdotal evidence suggesting potential efficacy of mycophenolate, we wished to explore the feasibility and effectiveness of this treatment in patients with CRPS.. A randomised, open, parallel, proof of concept trial was conducted. Patients with Budapest research criteria CRPS of >2-year duration and moderate or high pain intensity (numeric rating scale score ≥5) were enrolled. Eligible patients were randomised 1:1 to openly receive mycophenolate as add-on treatment, or their usual treatment alone, over 5.5 months. They then switched to the other treatment arm for 5.5 months. The main outcome was average the patients' average pain intensity recorded over 14 days, between 5.0 and 5.5 months post randomisation, on 11-point (0-10) numeric rating scales, compared between trial arms. Skin sensitivities and additional outcomes were also assessed.. Twelve patients were enrolled. Nine provided outcomes and were analysed for the main outcome. Mycophenolate treatment was significantly more effective than control [drug-group mean (SD): pre: 7.4 (1.2)- post: 5.2 (1.3), n=4, control: pre: 7.7 (1.4)- post: 8.1 (0.9), n=5; -2.8 (95% CI: -4.7, -1.0), p=0.01, analysis of covariance]. There were four treatment responders (to mycophenolate treatment either before, or after switch), whose initial exquisite skin hyper-sensitivities, function and quality of life strongly improved. Side effects including itchiness, skin-cryptitis, increased pain, and increased depression caused 45% of the subjects to stop taking mycophenolate.. Mycophenolate appears to reduce pain intensity and improve quality of life in a subgroup of patients with persistent CRPS.. These results support the feasibility of conducting a definite trial to confirm the efficacy and effect size of mycophenolate treatment for persistent CRPS (EudraCT 2015-000263-14).

Topics: Adult; Analgesics, Non-Narcotic; Chronic Pain; Complex Regional Pain Syndromes; Humans; Male; Middle Aged; Mycophenolic Acid; Pain Management; Proof of Concept Study; Quality of Life; Treatment Outcome

Objectives Complex regional pain syndrome (CRPS) is a rare chronic pain condition for which no curative treatment exists. Patients in tertiary centres are often required to make decisions about treatment options. This study was conducted to explore how prior attendance of a pain management program might alter patients' decision making processes. Methods This qualitative study uses focus groups to gather patient views on an immunosuppressant drug treatment (mycophenolate) for the management of CRPS. Participants were allocated to one of three focus groups based on their treatment journey; Group 1 (n=3) were involved in a recent mycophenolate drug trial; Group 2 (n=5) were neither involved in the trial nor attended a Pain Management Programme (PMP); Group 3 (n=6) were not involved in the trial but had attended a PMP. Outcomes were considered within the framework of Leventhal's Common Sense Model (CSM) in relation to the decision making process. Results Thematic analysis identified differing themes for each group. Group 1: (1) Medication as a positive form of treatment, (2) The trial/drug and (3) Pacing. Group 2: (1) Medication as form of treatment, (2) Other forms of support/treatment and (3) Side effects of mycophenolate. Group 3: (1) Varied view of medication, (2) Consideration of other forms of support and (3) Side effects. Conclusions Attendance on a PMP might provide patients with skills to better manage uncertainty when faced with various treatment options. Leventhal's model goes some way to explaining this. The specific importance of, and benefit from understanding pacing when commencing an effective drug treatment for chronic pain became apparent.

Topics: Complex Regional Pain Syndromes; Decision Making; Focus Groups; Humans; Immunosuppressive Agents; Mycophenolic Acid; Pain Management; Patient Acceptance of Health Care; Qualitative Research