A Clinical Trial Evaluating the Efficacy and Safety of HSK55718 in Patients for Postoperative Pain Treatment in Abdominal Surgery

A Multicenter, Randomized, Double-Blind, Double-Dummy, Placebo- and Active-Controlled Phase II Clinical Study to Evaluate the Efficacy and Safety of HSK55718 Injection for Postoperative Pain Treatment in Abdominal Surgery

This is a multi-center, randomized, double-blind, double-dummy, placebo/active-controlled study. 200 subjects undergoing abdominal surgery under general anesthesia are planned to be enrolled and randomized into the HSK55718 group, morphine group, and placebo group.

Study Overview

• Status: Recruiting
• Conditions: Pain After Surgery
• Intervention / Treatment: Drug: morphine; Drug: HSK55718 dose level 3; Drug: HSK55718 dose level1; Drug: HSK55718 dose level2; Drug: Placebo control

• Study Type: Interventional
• Enrollment (Estimated): 200
• Phase: Phase 2

Contacts and Locations

• Study Contact: Name: Yongrui Wang; Phone Number: 028-67258779; Email: wangyr@haisco.com

Study Locations

• China
  • Hunan
    • Changsha, Hunan, China
      • Recruiting
      • The Third Xiangya Hospital of Central South University
      • Contact: Saiying Wang; Phone Number: 0731-88618150; Email: 1771303488@qq.com
  • Sichuan
    • Chengdu, Sichuan, China
      • Recruiting
      • Sichuan Provincial People's Hospital
      • Contact: Mengchang Yang; Phone Number: 028-87393632; Email: ymc681@126.com

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Age ≥18 years old, regardless of gender;
• 18 kg/m2≤BMI≤30 kg/m2;
• American Society of Anesthesiologists (ASA) gradeⅰ-ⅲ;
• Accept abdominal surgery under general anesthesia;
• Within 4 hours after the end of surgery, NRS≥4 in the resting state at any time;
• Fully understand and voluntarily participate this trial, and sign the informed consent form;

Exclusion Criteria:

• A history of cardiovascular, respiratory, neurological, or psychiatric diseases that meet the protocol-defined exclusion criteria.
• Clinically significant abnormalities in laboratory tests during the screening period.
• A history of severe drug allergy or known allergy to the investigational drug.
• Continuous use of opioid analgesics for more than 10 days for any reason within 3 months prior to randomization.
• Use of any medication that may affect analgesia, where the last dose was administered less than 5 half-lives of that drug before randomization.
• A history of drug abuse, substance abuse, and/or alcohol abuse within the past year.
• Pregnant or lactating women.
• Participation in another drug clinical trial within 3 months prior to the screening period.
• Presence of any sensory dysfunction.
• Presence of any painful physical condition.
• Subjects with any other factor considered by the investigator to be ineligible for participation in the trial.

Study Plan

How is the study designed?

Design Details

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

Number of Arms

5

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: morphine	Drug: morphine; Patients administrated with morphine
Placebo Comparator: Placebo control	Drug: Placebo control; Patients administrated with placebo
Experimental: HSK55718 dose level1	Drug: HSK55718 dose level1; Patients administrated with HSK55718 at dose level 1
Experimental: HSK55718 dose level 3	Drug: HSK55718 dose level 3; Patients administrated with HSK55718 at dose level 3
Experimental: HSK55718 dose level2	Drug: HSK55718 dose level2; Patients administrated with HSK55718 at dose level 2

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Sum of Pain Intensity Differences (SPID)	24 hours

Secondary Outcome Measures

Outcome Measure	Time Frame
Sum of Pain Intensity Differences (SPID) in other time frame	0-12 hours, 12-24 hours, 24-48 hours, 48 hours
Number of times rescue analgesic medications were administered.	48 hours
Time to Pain Relief	0-48 hours
Postoperative Analgesia Satisfaction Score	48 hours

Collaborators and Investigators

• Sponsor: Haisco Pharmaceutical Group Co., Ltd.

Study record dates

Study Major Dates

• Study Start (Actual): May 22, 2026
• Primary Completion (Estimated): November 22, 2026
• Study Completion (Estimated): November 22, 2026

Study Registration Dates

• First Submitted: April 9, 2026
• First Submitted That Met QC Criteria: April 9, 2026
• First Posted (Actual): April 16, 2026

Study Record Updates

• Last Update Posted (Actual): May 28, 2026
• Last Update Submitted That Met QC Criteria: May 24, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Heterocyclic Compounds; Heterocyclic Compounds, Fused-Ring; Alkaloids; Polycyclic Aromatic Hydrocarbons; Polycyclic Compounds; Heterocyclic Compounds, 4 or More Rings; Morphinans; Opiate Alkaloids; Heterocyclic Compounds, Bridged-Ring; Phenanthrenes; Morphine Derivatives; Morphine
• Other Study ID Numbers: HSK55718-201

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