CM336 for Active Sjogren's Syndrome Study

Evaluation of CM336 Injection for Active Sjogren's Syndrome: an Open-Label Phase Ib Study

The purpose of this study is to evaluate the safety, tolerability, pharmacokinetics, and efficacy of CM336 in adult participants with active primary Sjogren's Syndrome.

Study Overview

• Status: Not yet recruiting
• Conditions: Primary Sjögren's Syndrome (pSS)
• Intervention / Treatment: Biological: CM336

Detailed Description

An open-label, multicenter, multiple ascending dose study evaluating safety, tolerability,PK/ADA profile and efficacy of CM336 administered subcutaneously in active primary Sjogren's Syndrome.

• Study Type: Interventional
• Enrollment (Estimated): 30
• Phase: Phase 1

Contacts and Locations

• Study Contact: Name: Qian Jia; Phone Number: 86+028-88610620; Email: clinicaltrial@keymedbio.com

Study Locations

• China
  • Beijing Municipality
    • Beijing, Beijing Municipality, China
      • Peking Union Medical College Hospital
      • Contact: Xiaofeng Zeng; Phone Number: 86+028-88610620; Email: clinicaltrial@keymedbio.com
      • Principal Investigator: Xiaofeng Zeng, Chief physician

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Male or female, aged 18 to 75 years (inclusive) at the time of signing the informed consent form (ICF), and willing to comply with the study protocol requirements.
• Body weight ≥ 45 kg at screening.
• Voluntary compliance with the protocol requirements for permitted/prohibited concomitant therapies.

• Definitive diagnosis of primary Sjögren's disease (SjD) according to the 2016 American College of Rheumatology (ACR)/European League Against Rheumatism (EULAR) classification criteria, and meeting all of the following requirements:

  1. Seropositive for at least one SjD-related autoantibody.
  2. Prior treatment with at least two systemic therapies for SjD symptoms.
  3. Active disease at screening, defined as Clinical EULAR Sjögren's Syndrome Disease Activity Index(ClinESSDAI) ≥ 5.
• No better therapeutic alternative available for the study participant.

Exclusion Criteria:

• Presence of other systemic autoimmune diseases besides primary Sjögren's disease.
• Presence of other autoimmune or inflammatory diseases.
• Presence of any other medical condition with clinical manifestations overlapping with primary Sjögren's disease or that may interfere with result interpretation.
• Presence of active, life-threatening, or organ-threatening SjD complications at screening.
• History of severe allergic reactions (as judged by the investigator), or history of hypersensitivity to monoclonal antibodies or any component of CM336.
• Presence of congenital immunodeficiency, or acquired immunodeficiency not related to the participant's autoimmune disease or its medical treatment.
• Positive HIV antibody, positive Treponema pallidum antibody, or history of hepatitis B virus (HBV) or hepatitis C virus (HCV) infection.
• History of tuberculosis infection.
• Active infection requiring intravenous anti-infective treatment within 3 months before first dose of study drug, or oral anti-infective treatment within 2 weeks before first dose of study drug.
• History of disseminated herpes zoster, or ocular/Central Nervous System herpes zoster, or systemic herpes simplex or symptomatic herpes zoster infection within 3 months before first dose of study drug.
• Deep vein thrombosis or pulmonary embolism within 6 months before first dose of study drug.

• History of severe cardiovascular or cerebrovascular disease, including but not limited to:

  1. Unstable arrhythmia, unstable angina pectoris.
  2. New York Heart Association (NYHA) functional class III or IV.
  3. Uncontrolled hypertension (average systolic blood pressure ≥160 mmHg or diastolic blood pressure ≥100 mmHg on two measurements despite optimal treatment).
  4. Fridericia-corrected QT interval(QTcF) >450 ms for males or >470 ms for females
• History of pulmonary arterial hypertension with WHO functional class II or above.
• Presence of uncontrolled asthma or chronic obstructive pulmonary disease (COPD); uncontrolled diabetes mellitus; uncontrolled thyroid or other endocrine disorders; uncontrolled psychiatric disorders.

• Presence of any of the following during screening:

  1. Neutrophil count <1×10⁹/L, platelet count <100×10⁹/L, or hemoglobin <80 g/L (applicable only to patients without hematologic involvement).
  2. Aspartate aminotransferase (AST) or alanine aminotransferase (ALT) >2× upper limit of normal (ULN).
  3. estimated Glomerular Filtration Rate(eGFR) <40 mL/min/1.73m² (2021 Chronic Kidney Disease Epidemiology Collaboration formula).
  4. Prothrombin time (PT) or activated partial thromboplastin time (APTT) >1.5×Upper Limit of Normal.
• Major surgery within 3 months before screening or planned during the study period (requiring hospitalization and general anesthesia, excluding diagnostic procedures).
• History of malignancy within 5 years before first dose of study drug (except cured basal cell carcinoma, squamous cell carcinoma of the skin, and cervical carcinoma in situ without evidence of recurrence).
• Prior treatment with any anti-B-cell maturation antigen targeted therapy (including cell therapy or antibody therapy, etc.).
• Receipt of prohibited medications within the corresponding timeframes.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: CM336 dose escalation	Biological: CM336; Participants will receive CM336 via subcutaneous injection in ascending dose cohorts

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Safety of drug administration	severity of treatment-emergent adverse events (TEAEs)	Throughout study (Up to 52 weeks)
Tolerability of drug administration	Incidence of treatment-emergent adverse events (TEAEs)	Throughout study (Up to 52 weeks)

Collaborators and Investigators

• Sponsor: Keymed Biosciences Co.Ltd

Study record dates

Study Major Dates

• Study Start (Estimated): June 1, 2026
• Primary Completion (Estimated): April 1, 2028
• Study Completion (Estimated): February 1, 2029

Study Registration Dates

• First Submitted: June 8, 2026
• First Submitted That Met QC Criteria: June 8, 2026
• First Posted (Actual): June 11, 2026

Study Record Updates

• Last Update Posted (Actual): June 11, 2026
• Last Update Submitted That Met QC Criteria: June 8, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Other Study ID Numbers: CM336-127001

Drug and device information, study documents

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