A Study of CLN-978, a Subcutaneously Administered CD19-directed T Cell Engager, in Subjects With Rheumatoid Arthritis

NCT06994143 | Recruiting Phase 1

• 1 other identifier: CLN-978-RA-101
• Study Type: interventional
• Target: 37
• Locations: 2 countries
• Sites: 2

Brief Summary

A Phase I, open-label study of CLN-978 in patients with treatment-refractory rheumatoid arthritis.

Conditions

Rheumatoid Arthritis (RA

Keywords

RA; Treatment-refractory RA

Outcome Measures

Primary Outcomes (1)

• Incidence and severity of adverse events

  Incidence and severity of adverse events (AEs)/adverse events of special interest (AESIs)/serious adverse events (SAEs)

  48 wks

Secondary Outcomes (3)

• Serum concentrations of CLN-978

  12 wks

• Level of anti-drug antibodies

  12 wks

• Pharmacodynamics-related biomarker

  48 wks

Study Arms (2)

Part A: Dose Escalation

EXPERIMENTAL

Patients with RA treated with CLN-978 in dose escalation cohorts

Drug: CLN-978

Part B Further Dose Evaluation

EXPERIMENTAL

Further evaluation of CLN-978 treatment of patients with RA

Drug: CLN-978

Interventions

CLN-978 DRUG

Specified dose on specified days

Part A: Dose Escalation; Part B Further Dose Evaluation

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Documented diagnosis of RA which fulfills the 2010 American College of Rheumatology (ACR)/European League Against Rheumatism (EULAR) Classification Criteria ≥12 weeks prior to screening.
• Evidence of B-cell-driven disease at Screening or previous medical documentation, defined as either (i) seropositivity for RF and/or any AMPA and/or (ii) a synovial biopsy showing B-cell infiltration
• Active RA disease, as demonstrated by a DAS28 - ESR ≥3.2 and at least one swollen joint at screening.
• Inadequate response to at least 2 targeted treatments with different mechanisms. These can include tsDMARD and/or bDMARD, after failing conventional synthetic DMARD (unless contraindicated).
• Local laboratory assessments must meet the following criteria:
• Absolute lymphocyte count (ALC) ≥0.5 x 10\^9/L
• Peripheral CD19+ B cell count ≥25 cells/μL
• Absolute neutrophil count (ANC) ≥1.0 x 10\^9/L
• Hemoglobin (Hgb) ≥8 g/dL
• Platelet count ≥75 x 10\^9/L
• Estimated glomerular filtration rate (eGFR) (based on the Chronic Kidney Disease Epidemiology Collaboration \[CKD-EPI\] formula) ≥30 mL/min/1.73m\^2
• Total bilirubin ≤1.5 × ULN, except patients with confirmed Gilbert's Syndrome
• Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤2.5 × ULN
• Concurrent corticosteroids is permitted if the dose is ≤10 mg/day prednisone equivalent in the 2 weeks prior to initiation of study treatment. Hydroxychloroquine ≤400 mg/d or chloroquine ≤ 250 mg/d is allowed.

You may not qualify if:

• Active inflammatory disease other than RA within 12 months prior to screening or during screening that may interfere with the study assessments. Thyroiditis or secondary Sjogren's syndrome is allowed.
• Clinical evidence of any other significant unstable or uncontrolled acute or chronic disease not due to RA which, in the opinion of the Investigator could put the patient at undue risk or confound study results.
• Prior treatment with the following:
• Cellular therapy (e.g., chimeric antigen receptor T-cell (CAR-T) or gene therapy product directed at any target.
• Receipt of an investigational therapy within 30 days or 5 drug-elimination half-lives (whichever is longer) prior to Day 1 and during the study.
• Received any anti-CD19 or anti-CD20 therapy such as blinatumomab, obinutuzumab, rituximab, ocrelizumab, or ofatumumab within 3 months prior to Day 1.
• Non-biologic DMARD within 14 days prior to Day 1.
• Cyclophosphamide or a biologic immunomodulating therapy within 2 months of Day 1.
• Live or live-attenuated vaccines within the 4 weeks prior to the Screening visit or during the Screening Period
• Active or latent tuberculosis (TB) evidenced by a positive or indeterminant Interferon Gamma Release Assay (IGRA), unless the patient has documented previous completion of TB treatment and no current clinical indication of TB.

Sponsors & Collaborators

• Cullinan Therapeutics Inc.: lead

Study Sites (2)

Cullinan Investigative Site

Erlangen, Germany

RECRUITING

Cullinan Investigative Site

Rome, Italy

RECRUITING

MeSH Terms

Conditions

Arthritis, Rheumatoid

Condition Hierarchy (Ancestors)

Arthritis; Joint Diseases; Musculoskeletal Diseases; Rheumatic Diseases; Connective Tissue Diseases; Skin and Connective Tissue Diseases; Autoimmune Diseases; Immune System Diseases

Central Study Contacts

Amy Gubits, MPH

CONTACT

1 617 410 4650; ClinOps@cullinantx.com

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SEQUENTIAL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: May 20, 2025
• First Posted: May 29, 2025
• Study Start: May 19, 2025
• Primary Completion (Estimated): December 30, 2027
• Study Completion (Estimated): December 30, 2028
• Last Updated: July 4, 2025

Record last verified: 2025-07

Locations

IT (1); DE (1)