A Phase 1b Open-label Study to Evaluate Safety of Plamotamab in Participants With Rheumatoid Arthritis

A Phase 1b, Open-label, Dose-Escalation Trial to Evaluate Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of Plamotamab in Participants With Rheumatoid Arthritis

Status

Recruiting

Phases

Phase 1

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT07230353

Enrollment

Registered

2025-11-17

Start date

2025-10-21

Completion date

2028-06-01

Last updated

2026-08-03

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Rheumatoid Arthritis

Keywords

Rheumatoid Arthritis, Arthritis Rheumatoid, Arthritis

Brief summary

The purpose of this study is to determine the safety and tolerability of plamotamab in patients with rheumatoid arthritis. Participants will be given XmAb13676 subcutaneously (SC) by injection under the skin.

Detailed description

This is a Phase 1b study to determine the safety, tolerability, pharmacokinetic (PK), and pharmacodynamics (PD), and immunogenicity of plamotamab in adult participants with moderately to severely active RA. This is an open label dose optimization trial with approximately 68 participants assigned to different dose escalation cohorts.

Interventions

BIOLOGICALPlamotamab

Biological

Study design

Allocation

Intervention model

SINGLE_GROUP

Primary purpose

TREATMENT

Masking

NONE

Eligibility

Sex/Gender

ALL

Age

18 Years to No maximum

Healthy volunteers

Inclusion criteria

Adult participants with moderately to severely active RA. * Documented diagnosis of RA and meeting the 2010 American College of Rheumatology/European Alliance of Associations for Rheumatology classification criteria for RA at least 3 months prior to screening * Inadequate response to, loss of response to, or intolerance to available RA therapies. * Stable doses of RA medications prior to screening * Use of highly effective methods of contraception

Exclusion criteria

* Major surgery within 12 weeks prior to screening or planned within 12 months after dosing * Recurrent infections or active clinically significant infection * Active or untreated latent tuberculosis * Cancer or history of cancer or lymphoproliferative disease within the previous 5 years * Uncontrolled cardiovascular, pulmonary, renal, hepatic, endocrine, or gastrointestinal disease Note: Additional, more specific inclusion/

Design outcomes

Primary

Measure	Time frame	Description
Primary	Through Week 52	Percentage of participants with treatment emergent adverse events (TEAEs) and serious adverse events (SAEs)

Secondary

Measure	Time frame	Description
Secondary	Through Week 52	Serum concentration of plamotamab

Countries

Georgia, Moldova, New Zealand

Contacts

CONTACT676-06 Study Information

676-Aiinfo@xencor.com

STUDY_DIRECTOR676-06 Study Information

Xencor, Inc.

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Aug 4, 2026