A Study of SRSD384 in Overweight or Obese Participants

A Phase 1/2a, Randomized, Double Blind, Placebo Controlled, Dose-Escalation Study to Evaluate the Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of Subcutaneously Administered SRSD384 in Overweight or Obese Participants

This is a two-part study, intended to investigate the safety, tolerability, characteristics of PK and PD of single SC dose of SRSD384 alone in overweight or obese participants (Part A) and in combination with tirzepatide in overweight or obese participants with T2DM (Part B).

Study Overview

• Status: Not yet recruiting
• Conditions: Overweight , Obesity
• Intervention / Treatment: Drug: SRSD384 injection; Drug: Placebo

• Study Type: Interventional
• Enrollment (Estimated): 78
• Phase: Phase 2; Phase 1

Contacts and Locations

• Study Contact: Name: Medical Director
• Study Contact Backup: Name: Medical Director; Phone Number: +86 21 61207756; Email: medical@siriusrna.com

Study Locations

• Australia
  • New South Wales
    • Charlestown, New South Wales, Australia, 2290
      • Novatrials
      • Principal Investigator: Deniz Kugulugil, MD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Able to comprehend and willing to sign an informed consent form (ICF) and to abide by the study restrictions;
• Males or females;
• Body mass index (BMI) between 27.0 and 40.0 kg/m2, inclusive;
• Male subjects are not allowed to donate sperm, and female subjects are not allowed to donate eggs from the time the ICF is signed until at least 3 months after the last follow-up.

Exclusion Criteria:

• Obesity attributable, in the investigator's opinion, to medication use, endocrinologic or monogenic disorders;
• Having a significant medical history or clinical manifestations related to any allergic, dermatological, hepatic, renal, hematological, pulmonary, cardiovascular, gastrointestinal, neurological, respiratory, endocrine (other than overweight or obesity), or psychiatric conditions that are severe or unstable (determined by the investigator or medically qualified designee);
• Evidence of active cancer within 2 years prior to screening (non-melanoma skin cancer, localized prostate cancer treated with curative intent, or other in situ carcinoma that does not require systemic therapy and is considered cured for at least 1 year is allowed);
• Acute febrile illness within 7 days prior to randomization or evidence of active infection
• Any major surgery within 3 months prior to screening or plan to have any major surgery during the study;
• History of clinically significant hypersensitivity, intolerance, or allergy to any oligonucleotide or GalNAc as determined by the investigator;
• Receipt of an investigational drug within 30 days or 5 half-lives of that drug, whichever is longer, prior to dose administration in this study;
• Have previously completed or withdrawn from this study or any other study investigating SRSD384 and have previously received SRSD384.

Study Plan

How is the study designed?

Design Details

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

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: SRSD384 injection (Part A)	Drug: SRSD384 injection; Administered S.C. per the protocol
Placebo Comparator: 0.9% Sodium Chloride (Part A)	Drug: Placebo; Administered S.C. per the protocol
Experimental: SRSD384 injection (Part B)	Drug: SRSD384 injection; Administered S.C. per the protocol
Placebo Comparator: 0.9% Sodium Chloride (Part B)	Drug: Placebo; Administered S.C. per the protocol

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Incidence of treatment-emergent adverse events (TEAEs)	168 days

Secondary Outcome Measures

Outcome Measure	Time Frame
Maximal concentration of SRSD384	48 hours
Area under the concentration-time curve from time 0 to infinity of SRSD384	48 hours
Time to the maximal concentration of SRSD384	48 hours

Collaborators and Investigators

• Sponsor: Sirius Therapeutics Co., Ltd.

Study record dates

Study Major Dates

• Study Start (Estimated): June 1, 2026
• Primary Completion (Estimated): October 1, 2027
• Study Completion (Estimated): October 1, 2027

Study Registration Dates

• First Submitted: April 22, 2026
• First Submitted That Met QC Criteria: April 22, 2026
• First Posted (Actual): April 29, 2026

Study Record Updates

• Last Update Posted (Actual): June 5, 2026
• Last Update Submitted That Met QC Criteria: June 3, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Nutrition Disorders; Overnutrition; Body Weight; Pathological Conditions, Signs and Symptoms; Nutritional and Metabolic Diseases; Signs and Symptoms; Overweight; Obesity
• Other Study ID Numbers: SRSD384-101

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

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