NCT06807164

Serratus Plane Block (SPB) Versus Capsaïcine Versus Botox-A for Chronic Neuropathic Pain in Post-mastectomy Syndrome

• Status: Recruiting
• Phase: Phase 2
• Study type: Interventional
• Enrollment: 123 (estimated)
• Sponsor: Centre Oscar Lambret · Academic / Other
• Sex: Female
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

The goal of this phase II clinical trial is to study the effectiveness of a treatment with Serratus Plane Block (SPB) or Botox-A in comparison with capsaicin for the control of chronic neuropathic pain of post-mastectomy syndrom, that is not adequately managed by systemic treatment alone. The primary outcome will be the pain evaluation at 8 weeks. 123 patients with chronic neuropathic pain of post-mastectomy syndrom insufficiently relieved by systemic treatment alone will be recruited over 24 months at the Centre Oscar Lambret. Patients will be randomly assigned to one of three treatment groups (41 patients per group): Capsaicin Botulinum toxin A SPB Patients will be followed for 24 weeks after the study treatment. The follow-up will include remote evaluation and 2 medical visits during which pain and quality of life will be assessed.

Detailed description

SerCaBot is a randomized, open-label, phase II clinical trial designed to evaluate the efficacy of a treatment with Serratus Plane Block (SPB) or Botox-A compared to capsaicin for the control of chronic neuropathic pain of post-mastectomy syndrom, that is not adequately managed by systemic treatment alone. 123 patients with will be recruited over 24 months at the Centre Oscar Lambret. This clinical trial will be proposed to patients with chronic neuropathic pain of post-mastectomy syndrome that is not adequately managed by systemic treatment alone. After consent, an inclusion assessment will be carried out including clinical examination, anamnesis, pain assessment (questionnaires PCS, NPS, DN4, NPSI and collect of antalgic treatment) and evaluation of quality of life (questionnaire SF12) and depression (questionnaire HADS). Patients will then be randomly assigned to one of three treatment groups : Capsaicin, Botox-A, SPB (41 patients per group). The randomization will be balanced 1:1:1, controlled by minimisation (with a random factor set at 0.8) for the distribution of the following factors: * Pain level at enrolment (continuous NPS) * Axillary dissection (yes vs. no) * Loco-regional adjuvant radiotherapy (yes vs. no) * Prior change of systemic treatment (yes vs. no) The study treatment will be administered 1 to 2 weeks after randomization. Treatment will be stopped prematurely in the event of unacceptable toxicity or complication. In each group, a repeat of the treatment may be considered after 12 weeks if further pain control is required. In the SPB group, a repeat is also possible every 2 weeks. Patients will be followed for 24 weeks after the study treatment. Follow-up will include: * 2 medical visits at 8 weeks and at 24 weeks including pain assessment (questionnaires NPS, NPSI, record of antalgic treatment), record of adverse events related to study treatment and assessment of quality of life (SF12 questionnaire) and depression (questionnaire HADS). * remote assessment at week-1, week-2, week-4 and week-6 including assessment of pain (questionnaires NPS, NPSI, record of antalgic treatment) and record of adverse events. This remote assessment will be repeated in case of repetition of treatment at week 12. Patients will withdraw from the study after the 24 week medical visit. Early withdrawal will be possible in case of patient's decision of withdrawal, breast surgery during follow-up, or death.

Conditions

• Post-Mastectomy Neuropathic Pain Syndrome

Interventions

Type	Name	Description
DRUG	Capsaicin 8% Patch	One or two capsaicin patch (8%) are applied for 60 minutes to the site of neuropathic pain, in day-hospital. An oral, antalgic pre-medication may be done with one of the following medications (alone or association): paracetamol 1g, nefopam 30 mg, tramadol 100 mg, morphine 10mg, oxycodone 5mg. Capsaicin will be administered in addition to a systemic treatment that has been ongoing for at least 4 weeks. If pain persists, the capsaicin patch application may be repeated at 12 weeks.
PROCEDURE	Serratus Plane Block	The Serratus Plane Block (SPB) is a nerve block performed by a trained anesthesiologist to provide localized pain relief. It involves the injection of a local anesthetic: Maximum 150 mg naropeine combined with 150 μg clonidine hydrochloride into the serratus anterior plane under ultrasound guidance. An anesthesiologist will perform the procedure in a post-interventional recovery room, with light sedation.The SBP will be carried out in addition to a systemic treatment that has been ongoing for at least 4 weeks. The SPB may be repeated every two weeks up to four times in the initial 8-week period, with an additional repeat at 12 weeks if pain control remains insufficient.
PROCEDURE	Botulinum Toxin A	Botulinum Toxin A (Botox-A) is injected into the affected area, with a total of 300 units administered across up to 60 injection sites. An anesthesiologist will perform the procedure in a post-interventional recovery room, with light sedation. This intervention will be carried out in addition to a systemic treatment that has been ongoing for at least 4 weeks, and is aimed at providing prolonged pain relief for post-mastectomy neuropathic pain. Light sedation is provided, and injections may be repeated at 12 weeks if necessary.

Timeline

• Start date: 2026-03-31
• Primary completion: 2027-08-30
• Completion: 2027-12-30
• First posted: 2025-02-04
• Last updated: 2026-03-27

Locations

1 site across 1 country: France