A Phase 3 interventional study of efgartigimod in Primary Immune Thrombocytopenia, sponsored by argenx. Completed at 87 sites in 18 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-03-16.
Sponsored by argenx · Phase 3, Interventional, and Treatment
This is an open-label long-term multicenter phase 3 trial to evaluate the efficacy and safety of ARGX-113 in adult patients with primary ITP.
517 studies on the registry are indexed under Purpura, Thrombocytopenic, Idiopathic; 161 are open to participants now.
This study's enrollment of 101 is above the median of 60 across 381 interventional studies indexed under Purpura, Thrombocytopenic, Idiopathic.
Browse Purpura, Thrombocytopenic, Idiopathic studies →argenx is the lead sponsor of 87 studies on the registry; 33 are open to participants now.
Of its 22 completed or terminated interventional studies of FDA-regulated products, 16 (73%) have results posted.
Counted across the registry records on this site, refreshed daily.
6. Ability to understand the requirements of the additional 52-week treatment period of the trial, to provide written informed consent (including consent for the use and disclosure of research-related health information), and to comply with the trial protocol procedures (including required trial visits).
7. Patient has completed a 52-week treatment period.
Exclusion criteria:
patients receiving efgartigimod
Biological: efgartigimod
Intravenous infusion of efgartigimod
Also known as: ARGX-113
Frequency and severity of Adverse Events
Time frame: Up to 60 weeks
Frequency and severity of vital signs
Time frame: Up to 60 weeks
Frequency and severity of laboratory assessments
Time frame: Up to 60 weeks
Extent of disease control defined as the percentage of weeks in the trial with platelet counts of ≥50×10E9/L.
Time frame: Over the 52 weeks of treatment
Percentage of patients with overall platelet count response defined as achieving a platelet count of ≥50×10^9/L on at least 4 occasions at any time during the 52-week treatment period.
Time frame: Over the 52 weeks of treatment
Mean change from baseline in platelet count at each visit.
Time frame: Up to 60 weeks, at each visit
For patients rolling-over from the ARGX-113-1801 trial with a platelet count of <30×10^9/L: time to response is defined as the time to achieve 2 consecutive platelet counts of ≥50×10^9/L
Time frame: Up to 60 weeks, at each visit
The percentage of weeks in the trial with platelet counts of ≥30×109/L and at least 20×10E9/L above baseline.
Time frame: Over the 52 weeks of treatment
In patients with baseline platelet count of <15×10E9/L in the current trial (ARGX-113-1803), the percentage of weeks in the trial with platelet counts of ≥30×10E9/L and at least 20×10E9/L above baseline.
Time frame: Over the 52 weeks of treatment
In patients with first exposure to efgartigimod: proportion of patients who achieve a sustained platelet response defined as achieving platelet counts of at least 50×10^9/L for at least 4 of the 6 visits between week 19 and 24 of the trial.
Time frame: Up to 5 weeks, between visit 19 and 24 of the trial
In patients with first exposure to efgartigimod: proportion of patients in the overall population achieving platelet counts of at least 50x10^9/L for at least 6 of the 8 visits between week 17 and 24 of the trial.
Time frame: Up to 7 weeks, between visit 17 and 24 of the trial
Rate of receipt of rescue therapy (rescue per patient per month).
Time frame: Up to 60 weeks, at each visit
Reduction in concurrent ITP therapy.
Time frame: Up to 60 weeks, at each visit
Incidence and severity of the WHO-classified bleeding events.
Time frame: Up to 60 weeks, at each visit
Change from baseline in Patient reported Outcomes (FACIT-Fatigue) at planned visits.
Time frame: Up to 52 weeks
Change from baseline in Patient reported Outcomes (Fact-Th6) at planned visits.
Time frame: Up to 52 weeks
Change from baseline in Quality of Life (SF-36) at planned visits.
Time frame: Up to 52 weeks
Incidence of anti-drug antibodies (ADA) to efgartigimod.
Time frame: Up to 216 weeks
Pharmacokinetic parameter of efgartigimod: serum concentration observed predose (Ctrough).
Time frame: Up to 60 weeks
Pharmacodynamics markers: total IgG.
Time frame: Up to 60 weeks
Plan to share: Undecided
No publications or documents are linked to this record.
This study is completed, as verified in Mar 2026. You cannot join it, but the record below documents what was studied.
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Purpura, Thrombocytopenic, Idiopathic→
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