Perineural Incobotulinumtoxin-A for Complex Regional Pain Syndrome - An Open-label Feasibility Study (PINCom)
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.
• 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