A Phase 1 interventional study of XmAb657 in Healthy, Idiopathic Inflammatory Myopathies and Systemic Sclerosis, sponsored by Xencor, Inc.. Recruiting at 1 site in Australia. Open to participants aged 18 Years to 75 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-08-03.
Sponsored by Xencor, Inc. · Phase 1, Interventional, and Treatment
The purpose of this study is to determine the safety and tolerability of XmAb657 in healthy participants and participants with autoimmune diseases. Participants will be given XmAb657 subcutaneously (SC) by injection under the skin.
This is a Phase 1 study to determine the safety, tolerability, pharmacokinetic (PK), and pharmacodynamics (PD), and immunogenicity of XmAb657 in healthy adult participants and participants with autoimmune diseases.
215 studies on the registry are indexed under Myositis; 100 are open to participants now.
This study's planned enrollment of 60 is above the median of 30 across 141 interventional studies indexed under Myositis.
Browse Myositis studies →Xencor, Inc. is the lead sponsor of 30 studies on the registry; 7 are open to participants now.
Of its 15 completed or terminated interventional studies of FDA-regulated products, 2 (13%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Healthy participants - Adult participants in good health
Idiopathic inflammatory myopathy (IIM) participants - Adult participants that meet the 2017 European Alliance of Association Rheumatology (EULAR)/American College of Rheumatology (ACR) Classification Criterion for IIM
Systemic sclerosis (SSc) participants - Adult participants that meet the 2013 ACR/EULAR Classification Criteria for SSc
Sjogren's Disease participants that meet the 2016 ACR/EULAR Classification Criteria for Primary Sjogren's Syndrome
All participants - Use of highly effective methods of
Exclusion Criteria:
Note: Additional, more specific inclusion/exclusion criteria are defined in the protocol.
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
XmAb657 administered SC
Biological: XmAb657
Biological
Percentage of participants with treatment emergent adverse events (TEAEs) and serious adverse events (SAEs)
Time frame: Through Week 52
Serum concentration of XmAb657
Time frame: Through Week 52
Started Feb 2026 (actual). Primary completion is estimated for Oct 2028, 32 months after the start.
How these figures are worked out, and which studies are left out of them.
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