A Long-term Study to Assess the Safety and Efficacy of Efgartigimod in Adult Patients With Primary Immune Thrombocytopenia (ITP).

NCT04225156 | Completed Phase 3 DMC FDA Drug

• 2 other identifiers: ARGX-113-18032019-002101-21
• Study Type: interventional
• Target: 101
• Locations: 18 countries
• Sites: 87

Brief Summary

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.

Conditions

Primary Immune Thrombocytopenia

Outcome Measures

Primary Outcomes (3)

• Frequency and severity of Adverse Events

  Up to 60 weeks

• Frequency and severity of vital signs

  Up to 60 weeks

• Frequency and severity of laboratory assessments

  Up to 60 weeks

Secondary Outcomes (17)

• Extent of disease control defined as the percentage of weeks in the trial with platelet counts of ≥50×10E9/L.

  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.

  Over the 52 weeks of treatment

• Mean change from baseline in platelet count at each visit.

  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

  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.

  Over the 52 weeks of treatment

Study Arms (1)

efgartigimod

EXPERIMENTAL

patients receiving efgartigimod

Biological: efgartigimod

Interventions

efgartigimod BIOLOGICAL

Intravenous infusion of efgartigimod

Also known as: ARGX-113

efgartigimod

Eligibility Criteria

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

You may qualify if:

• Ability to understand the requirements 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).
• Patients enrolled in the ARGX-113-1801 trial who completed the 24-weeks trial period.
• Women of childbearing potential must have a negative urine pregnancy test at baseline before trial medication (infusion) can be administered.
• Women of childbearing potential should use a highly effective or acceptable method of contraception during the trial and for 90 days after the last administration of the IMP. They must be on a stable regimen, for at least 1 month (as listed in the protocol)
• \. 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).
• \. Patient has completed a 52-week treatment period.

You may not qualify if:

• Introduction or continuation of non-permitted medications during the ARGX-113-1801 trial (such as anti-CD20 therapy, romiplostim, monoclonal antibodies, Fc fusion proteins or live/live-attenuated vaccines).
• Pregnant or lactating women, and those intending to become pregnant during the trial or within 90 days after the last dosing.
• Patients with known medical history of hypersensitivity to any of the ingredients of efgartigimod.
• Use of any other investigational drug or participation in any other investigational trial.

Sponsors & Collaborators

• argenx: lead

Study Sites (87)

Investigator Site 0010045

Washington D.C., District of Columbia, 20007, United States

Location

Investigator Site 0010037

Ocala, Florida, 34474, United States

Location

Investigator Site 0010042

Iowa City, Iowa, 52242, United States

Location

Investigator Site 0010040

Columbus, Ohio, 43210, United States

Location

Investigator Site 0430002

Vienna, Austria

Location

Investigator Site 0430003

Vienna, Austria

Location

Investigator Site 0320012

Brasschaat, Belgium

Location

Investigator Site 0320011

Bruges, Belgium

Location

Investigator Site 0320014

Turnhout, Belgium

Location

Investigator Site 0320002

Yvoir, Belgium

Location

Investigator Site 3590001

Pleven, Bulgaria

Location

Investigator Site 3590002

Sofia, Bulgaria

Location

Investigator Site 4200001

Brno, Czechia

Location

Investigator Site 4200008

Olomouc, Czechia

Location

Investigator Site 4200006

Ostrava, Czechia

Location

Investigator Site 4200007

Prague, Czechia

Location

Investigator Site 0330009

Créteil, France

Location

Investigator Site 0330018

Montpellier, France

Location

Investigator Site 0330008

Pessac, France

Location

Investigator Site 0330016

Périgueux, France

Location

Investigator site 9950007

Tbilisi, Georgia

Location

Investigator site 9950008

Tbilisi, Georgia

Location

Investigator site 9950009

Tbilisi, Georgia

Location

Investigator site 9950011

Tbilisi, Georgia

Location

Investigator site 9950012

Tbilisi, Georgia

Location

Investigator Site 0490010

Düsseldorf, Germany

Location

Investigator Site 0490008

Essen, Germany

Location

Investigator Site 0360004

Budapest, Hungary

Location

Investigator Site 0360006

Debrecen, Hungary

Location

Investigator Site 0360015

Győr, Hungary

Location

Investigator Site 0360010

Nyíregyháza, Hungary

Location

Investigator Site 0360014

Szombathely, Hungary

Location

Investigator Site 0390014

Milan, Italy

Location

Investigator Site 0390020

Monza, Italy

Location

Investigator Site 0390015

Novara, Italy

Location

Investigator Site 0390010

Ravenna, Italy

Location

Investigator Site 0390011

Reggio Calabria, Italy

Location

Investigator Site 0390018

Reggio Emilia, Italy

Location

Investigator Site 0390019

Rimini, Italy

Location

Investigator Site 0390009

Siena, Italy

Location

Investigator Site 0390016

Trieste, Italy

Location

Investigator Site 0810015

Hirakata, Japan

Location

Investigator Site 0810010

Hiroshima, Japan

Location

Investigator Site 0810017

Iruma, Japan

Location

Investigator Site 0810022

Kashiwa, Japan

Location

Investigator Site 0810018

Maebashi, Japan

Location

Investigator Site 0810021

Niigata, Japan

Location

Investigator Site 0810014

Sapporo, Japan

Location

Investigator Site 0810016

Shibukawa, Japan

Location

Investigator Site 0810023

Shimotsuke, Japan

Location

Investigator Site 0310005

Rotterdam, Netherlands

Location

Investigator Site 0310006

The Hague, Netherlands

Location

Investigator Site 0480012

Gdansk, Poland

Location

Investigator Site 0480013

Katowice, Poland

Location

Investigator Site 0480011

Lodz, Poland

Location

Investigator Site 0480014

Lublin, Poland

Location

Investigator Site 0480026

Nowy Sącz, Poland

Location

Investigator Site 0070006

Kaluga, Russia

Location

Investigator Site 0070008

Moscow, Russia

Location

Investigator Site 0070007

Petrozavodsk, Russia

Location

Investigator Site 0070013

Rostov-on-Don, Russia

Location

Investigator Site 0070015

Syktyvkar, Russia

Location

Investigator Site 0070012

Tula, Russia

Location

Investigator Site 0070010

Ufa, Russia

Location

Investigator Site 0340006

Barcelona, Spain

Location

Investigator Site 0340007

Barcelona, Spain

Location

Investigator Site 0340009

Madrid, Spain

Location

Investigator Site 0340014

Madrid, Spain

Location

Investigator Site 0340012

Palma de Mallorca, Spain

Location

Investigator Site 0340015

Pozuelo de Alarcón, Spain

Location

Investigator Site 0340013

Seville, Spain

Location

Investigator Site 0340004

Valencia, Spain

Location

Investigator Site 0340011

Valencia, Spain

Location

Investigator Site 0900003

Ankara, Turkey (Türkiye)

Location

Investigator Site 0900006

Ankara, Turkey (Türkiye)

Location

Investigator Site 0900015

Ankara, Turkey (Türkiye)

Location

Investigator Site 0900016

Edirne, Turkey (Türkiye)

Location

Investigator Site 0900013

Istanbul, Turkey (Türkiye)

Location

Investigator Site 0900004

Izmir, Turkey (Türkiye)

Location

Investigator Site 0900010

Mersin, Turkey (Türkiye)

Location

Investigator Site 0900007

Sakarya, Turkey (Türkiye)

Location

Investigator Site 0900009

Samsun, Turkey (Türkiye)

Location

Investigator Site 0900017

Tekirdağ, Turkey (Türkiye)

Location

Investigator Site 0900019

Trabzon, Turkey (Türkiye)

Location

Investigator Site 3800006

Mykolaiv, Ukraine

Location

Investigator Site 0440008

London, United Kingdom

Location

Investigator Site 0440012

Southampton, United Kingdom

Location

MeSH Terms

Conditions

Purpura, Thrombocytopenic, Idiopathic

Interventions

efgartigimod alfa

Condition Hierarchy (Ancestors)

Purpura, Thrombocytopenic; Purpura; Blood Coagulation Disorders; Hematologic Diseases; Hemic and Lymphatic Diseases; Thrombotic Microangiopathies; Thrombocytopenia; Blood Platelet Disorders; Cytopenia; Hemorrhagic Disorders; Autoimmune Diseases; Immune System Diseases; Hemorrhage; Pathologic Processes; Pathological Conditions, Signs and Symptoms; Skin Manifestations; Signs and Symptoms

Study Design

• Study Type: interventional
• Phase: phase 3
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: January 6, 2020
• First Posted: January 13, 2020
• Study Start: June 2, 2020
• Primary Completion: March 11, 2026
• Study Completion: March 11, 2026
• Last Updated: March 16, 2026

Record last verified: 2026-03

Locations

NL (2); BE (4); DE (2); GE (5); PL (5); ES (9); CZ (4); IT (9); UA (1); AU (2); FR (4); US (4); HU (5); GB (2); JP (9); RU (7); TU (11); BU (2)