Anrikefon Injection for Postoperative Analgesia in Thoracoscopic Lung Surgery: A Randomized, Double-Blind, Active-Controlled, Parallel-Group, Single-Center Clinical Study

This is a randomized, double-blind, active-controlled clinical study evaluating the efficacy and safety of Anrikefon (HSK21542) Injection for patient-controlled analgesia (PCA) in patients undergoing thoracoscopic lung surgery. Subjects aged 18-85 years with a postoperative resting NRS score ≥ 4 will be enrolled. Eligible participants will be randomized 1:1 to receive either Anrikefon (HSK21542) or sufentanil via PCA pump for 24 hours post-surgery. The primary endpoint is the 24-hour summed pain intensity difference (SPID₂₄). A total of 88 subjects are planned for enrollment. The study has received ethics committee approval.

Study Overview

• Status: Not yet recruiting
• Conditions: Postoperative Pain
• Intervention / Treatment: Drug: Anrikefon Injection; Drug: Sufentanil Citrate Injection

• Study Type: Interventional
• Enrollment (Estimated): 88
• Phase: Not Applicable

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Age 18 to 85 years (inclusive), either sex.
2. Body mass index (BMI) 18.0 to 30.0 kg/m² (inclusive).
3. American Society of Anesthesiologists (ASA) physical status Class I to III preoperatively.
4. Undergoing elective thoracoscopic lung surgery under general anesthesia (complete video-assisted thoracoscopic surgery, without conversion to thoracotomy), with successful recovery from anesthesia within 1 hour postoperatively, fully awake, able to accurately complete NRS scoring with an NRS score ≥ 4, and willing to accept the analgesic regimen defined in the study protocol.
5. Able to understand the purpose, procedures, and scale scoring methods of the study, capable of operating the PCA device, and able to communicate effectively with investigators.
6. Voluntarily participating and providing written informed consent.

Exclusion Criteria:

1. Known or suspected allergy or contraindication to any of the study drugs.
2. History of opioid abuse, drug or alcohol dependence, or current preoperative use of opioids.
3. Use of analgesic medications (acetaminophen, NSAIDs, opioids, tramadol, etc.) within 24 hours preoperatively.
4. Uncontrolled severe cardiovascular disease (second-degree or higher atrioventricular block, resting heart rate < 50 bpm, uncontrolled hypertension, myocardial infarction or unstable angina within the past 6 months), hepatic insufficiency (ALT/AST > 2× upper limit of normal), renal insufficiency (eGFR < 30 mL/min/1.73m² or maintenance dialysis), neuropsychiatric dysfunction, or inability to cooperate with pain assessment.
5. History of chronic pain.
6. Severe respiratory or circulatory failure during anesthesia/surgery (including intraoperative conversion to thoracotomy, operative time > 6 hours, or intraoperative hemorrhage > 1000 mL).
7. Pregnancy or lactation, or positive urine pregnancy test in women of childbearing potential.
8. Participation in another drug/device clinical trial within 30 days before randomization.
9. Any other condition that the investigator deems unsuitable for participation.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Anrikefon (HSK21542) Group	Drug: Anrikefon Injection; Active ingredient: Anrikefon. Specification: 1 mL: 0.1 mg. Dosage: diluted to working solution of 10 μg/mL in 100 mL; loading dose 1.0 μg/kg; PCA bolus 2 mL per demand; lockout interval 15 min.
Active Comparator: Sufentanil Group	Drug: Sufentanil Citrate Injection; Specification: 1 mL: 50 μg. Dosage: 2 μg/kg diluted to 100 mL solution; loading dose 0.1 μg/kg; PCA bolus 2 mL per demand; lockout interval 15 min.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Sum of Pain Intensity Difference over 24 Hours (SPID₂₄)	0 to 24 hours after first dose

Secondary Outcome Measures

Outcome Measure	Time Frame
Number and Dose of Rescue Medication	0 to 24 hours after first dose
Incidence of Postoperative Nausea and Vomiting (PONV) at 24 Hours	0 to 24 hours after first dose
PCA Pump Demand (Total, Effective, and Delivered Dose)	0 to 24 hours after first dose
Time to First Rescue Medication	0 to 24 hours after first dose
Proportion of Subjects Requiring Rescue Medication	0 to 24 hours after first dose
Treatment Failure Rate Due to Inadequate Analgesia	0 to 24 hours after first dose

Collaborators and Investigators

• Sponsor: The First People's Hospital of Lianyungang

Study record dates

Study Major Dates

• Study Start (Estimated): September 30, 2026
• Primary Completion (Estimated): December 31, 2026
• Study Completion (Estimated): May 30, 2027

Study Registration Dates

• First Submitted: September 3, 2026
• First Submitted That Met QC Criteria: September 3, 2026
• First Posted (Actual): September 9, 2026

Study Record Updates

• Last Update Posted (Actual): September 9, 2026
• Last Update Submitted That Met QC Criteria: September 3, 2026
• Last Verified: August 1, 2026

More Information

Terms related to this study

• Keywords: Sufentanil; Thoracic Surgery; Anrikefon
• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Postoperative Complications; Pathologic Processes; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Pain, Postoperative; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Piperidines; Fentanyl; Sufentanil
• Other Study ID Numbers: KY-20250709002-02

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No