Perineural incobotulinumtoxin-A for unilateral CRPS of an arm or leg
Perineural Incobotulinumtoxin-A for Complex Regional Pain Syndrome - An Open-label Feasibility Study (PINCom)
This study will try a single ultrasound-guided perineural injection of incobotulinumtoxin-A to see if it is safe and tolerable for adults with long-standing unilateral CRPS of an arm or leg.
Quick facts
| Phase | Not applicable |
|---|---|
| Study type | Interventional |
| Enrollment | 20 (estimated) |
| Ages | 18 Years and up |
| Sex | All |
| Sponsor | Rigshospitalet, Denmark Academic / other |
| Locations | 1 site (Glostrup, Region Sjælland) |
| Trial ID | NCT07473635 on ClinicalTrials.gov |
What this trial studies
The PINCom study is a single-center, open-label feasibility study testing a single ultrasound-guided perineural injection of 200 U incobotulinumtoxin-A in adults with unilateral chronic CRPS of an upper or lower limb. Injection sites are chosen based on symptom distribution and include the supraclavicular brachial plexus for upper-limb CRPS or distal sciatic and/or femoral nerve targets for lower-limb CRPS, all performed under ultrasound guidance in one treatment session. Primary outcomes focus on feasibility measures such as recruitment rate, retention, adherence to visits and daily pain diaries, and completeness of outcome data, while safety is monitored via adverse event reporting and targeted screening for procedure-related complications and systemic toxin spread. Tolerability and participant experience are assessed with structured symptom monitoring and a semi-structured qualitative interview during follow-up.
Who should consider this trial
Good fit: Adults (≥18) with unilateral CRPS type I or II of an arm or leg for at least six months who meet the Budapest research criteria, are on a stable analgesic regimen, and can read and speak Danish.
Not a fit: Patients with allergy to botulinum toxin A, recent botulinum toxin treatment within three months, neuromuscular disorders (e.g., myasthenia gravis, Lambert-Eaton, ALS), active infection in the affected limb, or inability to undergo ultrasound-guided perineural injection are unlikely to benefit.
Why it matters
Potential benefit: If successful, this approach could offer a targeted, potentially less painful perineural option to reduce neuropathic pain and flare-ups in CRPS and inform larger trials.
How similar studies have performed: Perineural botulinum toxin A has shown analgesic effects in some other neuropathic pain conditions, but its use specifically for CRPS is novel and has not been tested in randomized trials.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion Criteria: * Are over the age of 18 * Have a diagnosis of CRPS type 1 or 2 in either one upper or one lower extremity which fulfils the Budapest research criteria * Have had the condition for at least 6 months * Rate CRPS as their primary pain condition * Have been on a stable analgesic regimen, including any rescue medications, for at least 1 month prior to the study and intend to maintain this regimen throughout the study * For pre-menopausal females: are using a safe and approved contraceptive * Speak, read, and understand Danish Exclusion Criteria: * Are allergic to botulinum toxin A * Have been treated with botulinum toxin A for any indication within 3 months prior to study start * Are diagnosed with myasthenia, Lambert-Eaton syndrome, amyotrophic lateral sclerosis, or any other condition which makes differentiation of CRPS-specific pain difficult * Have an ongoing infection in the affected limb * Do not intend to start physical therapy, psychotherapy, or any other non-pharmaceutical intervention aimed at reducing pain * Have used a topical analgesic treatment such as lidocaine patches within 1 week prior to study start or have been treated with capsaicin patches in the affected area within 3 months prior to study start * Have psychiatric comorbidities which are considered by the investigators to impact their ability to participate * Consume alcohol in excess of what is recommended by the Danish Health Ministry * Are active abusers of illicit narcotics * Are pregnant, lactating, or plan on becoming pregnant during the study period * Have any other condition or circumstance that, in the investigators' opinion, will hinder safe and timely participation and completion of the study
Where this trial is running
Glostrup, Region Sjælland
- CRPS- and Nerve Pain Clinic, Rigshospitalet Glostrup — Glostrup, Region Sjælland, Denmark (Recruiting)
Study contacts
- Study coordinator: Marc K Olsen, MD
- Email: marc.klee.olsen@regionh.dk
- Phone: +45 38633030
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.