Feasibility Study of Subcutaneous Botulinum Toxin Type A (Xeomin) for Chronic Postsurgical Pain in Lung Cancer Surgery Patients

The primary objective is to assess the feasibility of a definitive trial of Botulinum toxin A for established chronic postsurgical pain after lung cancer resection by quantifying (1) the recruitment rate, (2) the proportion of screened patients who are enrolled, and (3) the overall study completion percentage; these metrics are essential to determine whether a larger efficacy study can be realistically conducted.

Secondary objectives include:

• Evaluation of the practical feasibility of subcutaneous administration in the chest wall of patients with chronic postsurgical pain.
• Assessment of tolerability and identification of adverse events following subcutaneous injection.
• Measurement of response rates to the questionnaires employed for pain and functional assessment.
• Proof‑of‑concept evaluation of analgesic effect of subcutaneous Botulinum toxin A in this patient population.

The trial enrolled adult patients (≥18 years) of both sexes who had undergone curative lung cancer resection, with or without (neo)adjuvant therapy, and were diagnosed with chronic postsurgical pain according to IASP criteria. Eligible participants reported at least moderate pain (≥4 on a 0–10 numerical rating scale) and/or neuropathic pain (DN4 score ≥4). Inclusion required fluency in Danish and, for premenopausal women, use of an approved contraceptive method. General health status was limited to individuals who were otherwise stable post‑surgery. The sponsor did not provide the total number of participants; consequently, the exact sample size is unavailable. Selection was based on screening of postoperative lung cancer patients who met the specified pain and language criteria, without additional lifestyle restrictions such as diet or physical activity reported.

The study is a Phase 4, feasibility trial evaluating subcutaneous Botulinum toxin A (Xeomin, 100 IU) for chronic postsurgical pain in patients who have undergone curative lung cancer surgery; eligibility requires age ≥18 years, moderate to severe pain (≥4 on the NRS or DN4 ≥ 4), and ability to understand Danish, with premenopausal women using approved contraception. After an initial screening visit to confirm inclusion criteria and obtain baseline assessments, eligible participants receive a single subcutaneous injection of the investigational product into the chest wall and are subsequently observed at scheduled follow‑up visits for collection of pain questionnaires, tolerability data, and adverse‑event monitoring. Participation extends from the screening visit through the final end‑of‑study visit, with the overall trial period defined by the recruitment window from September 2026 to February 2027. Primary feasibility outcomes include recruitment rate, enrollment proportion of screened patients, and study completion percentage, while secondary outcomes assess administration practicality, tolerability, questionnaire completion, and preliminary analgesic effect.

The investigational product is Xeomin, a powder for injection supplied as a 100‑unit solution for subcutaneous administration. Each vial contains clostridium botulinum neurotoxin type A (150 kDa), free of complexing proteins and is classified under ATC code M03AX01. The study protocol specifies a single subcutaneous injection of 100 IU (international units) delivered by qualified personnel, with the injection site and technique documented in the source data. Dosing is performed in accordance with the sponsor’s standard operating procedures, and participants are observed for a predefined post‑administration period to monitor safety and tolerability.

All participants continue to receive routine analgesic management as part of standard clinical practice for chronic post‑surgical pain. No additional investigational agents are administered, and any concomitant medications are recorded to ensure adherence to the study’s compliance monitoring plan, which includes regular review of medication logs and patient diaries.

Efficacy will be evaluated through the secondary objective of “proof of concept” for subcutaneous BTX‑A as pain relief in chronic postsurgical pain following lung cancer surgery. The assessment focuses on determining whether the intervention provides analgesic benefit in the target population.