Perineural Incobotulinumtoxin-A for Complex Regional Pain Syndrome - An Open-label Feasibility Study

NCT07473635 | Recruiting

• 2 other identifiers: PINCom2024-519832-17-00
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

Complex Regional Pain Syndrome (CRPS) is a chronic pain condition characterized by severe regional pain, sensory disturbances, and functional impairment. Current treatment options are limited, and many patients experience substantial pain-related disability and symptom fluctuations, including flare-ups triggered by invasive procedures. Perineural administration of botulinum toxin A has shown analgesic effects in other neuropathic pain conditions and may represent a less painful alternative to subcutaneous injection techniques. However, the feasibility, tolerability, and safety of perineural botulinum toxin administration in patients with CRPS have not been systematically evaluated. The PINCom study is a single-center, open-label feasibility study designed to assess the safety, tolerability, and practical feasibility of ultrasound-guided perineural injection of incobotulinumtoxin-A in patients with unilateral chronic CRPS affecting an upper or lower limb. Participants receive a single perineural injection targeting major sensory nerves supplying the affected limb and are followed for 12 weeks. Primary outcomes focus on feasibility metrics, including recruitment, retention, adherence, and data completeness, as well as safety outcomes, including serious adverse events and procedure-related complications. Tolerability is assessed through monitoring of CRPS flare-ups and a dedicated qualitative interview exploring participant experience. Exploratory outcomes include pain intensity, CRPS severity, and patient-reported measures collected to inform the design of a future randomized controlled trial.

Conditions

CRPS (Complex Regional Pain Syndromes); CRPS (Complex Regional Pain Syndrome) Type I; CRPS Type II

Keywords

botulinum toxin; CRPS; Pilot; perineural

Outcome Measures

Primary Outcomes (4)

• Recruitment rate

  Number of participants enrolled over time in the study

  From study start through Day 84 (12 weeks)

• Screening-to-enrolment ratio

  Proportion of screened patients who are enrolled in the study.

  From study start through Day 84

• Study completion rate

  Proportion of enrolled participants completing the study per protocol

  Day -7 to 84

• Completeness of study data

  Proportion of expected study data successfully collected, including completion of scheduled study visits and daily pain diary entries.

  Day -7 to 84

Secondary Outcomes (3)

• Serious Adverse Events (SAEs)

  From treatment (Day 0) through Day 84

• CRPS flare-ups

  From treatment (Day 0) through Day 84

• Participant-reported acceptability and experience

  From enrolment to day 42

Other Outcomes (8)

• Pain intensity (NRS)

  Day -7 to Day 84

• CRPS Disease Severity

  Baseline, Day 5, Day 28

• Sensory symptoms and allodynia

  Baseline, Day 28

Study Arms (1)

Active

EXPERIMENTAL

Open-label treatment with 200 U of perineural Xeomin, either around the brachial plexus or the distal ischial and saphenus nerves.

Drug: Perineural Incobotulinumtoxin-A 200 U

Interventions

Perineural Incobotulinumtoxin-A 200 U DRUG

Single perineural injection of 200 U iBonT-A around the brachial plexus in the case of upper limb CRPS, or 150 U iBonT-A around the distal ischial nerve and 50 U around the saphenus nerve in the case of lower limb CRPS.

Active

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• 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

You may not qualify if:

• 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

Sponsors & Collaborators

• Bo Biering-Soerensen: lead
• Merz Pharmaceuticals GmbH: collaborator
• The GCP unit at Copenhagen University Hospital: collaborator

Study Sites (1)

CRPS- and Nerve Pain Clinic, Rigshospitalet Glostrup

Glostrup, Region Sjælland, 2600, Denmark

RECRUITING

MeSH Terms

Conditions

Complex Regional Pain Syndromes; Causalgia

Condition Hierarchy (Ancestors)

Autonomic Nervous System Diseases; Nervous System Diseases; Peripheral Nervous System Diseases; Neuromuscular Diseases; Neuralgia

Central Study Contacts

Marc K Olsen, MD

CONTACT

+45 38633030; marc.klee.olsen@regionh.dk

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: OTHER
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Associate Professor

Study Record Dates

• First Submitted: January 26, 2026
• First Posted: March 16, 2026
• Study Start: January 7, 2026
• Primary Completion: July 1, 2026
• Study Completion: August 1, 2026
• Last Updated: March 16, 2026

Record last verified: 2026-03

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, ICF, CSR

Locations

DK (1)