A Phase 3 Study to Evaluate the Safety and Efficacy of Efgartigimod PH20 Subcutaneous in Adult Patients With Primary Immune Thrombocytopenia

NCT04812925 | Active Not Recruiting Phase 3 DMC FDA Drug

• 1 other identifier: ARGX-113-2005
• Study Type: interventional
• Target: 173
• Locations: 24 countries
• Sites: 81

Brief Summary

A Phase 3 study to evaluate the safety and efficacy of efgartigimod PH20 subcutaneous in adult patients with primary immune thrombocytopenia

Conditions

Primary Immune Thrombocytopenia

Outcome Measures

Primary Outcomes (4)

• Incidence, frequency, and severity of adverse events (AEs), AEs of special interest (AESIs), and serious AEs (SAEs)

  216 weeks

• Vital sign measurement: blood pressure in the overall population

  216 weeks

• ECG: PR, QT and QRS interval in the overall population

  216 weeks

• Laboratory safety evaluations: CRP analysis in the overall population

  216 weeks

Secondary Outcomes (27)

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

  52 weeks

• Proportion of patients with overall platelet count response defined as achieving a platelet count of ≥50×10E9/L on at least 4 occasions at any time during the 52-week treatment period

  52 weeks

• Mean change from baseline in platelet count at each visit

  52 weeks

• For patients rolling over from the ARGX-113-2004 trial with a platelet count of <30×10E9/L: time to response defined as the time to achieve 2 consecutive platelet counts of ≥50×10E9/L

  52 weeks

• The percentage of weeks in the trial with platelet counts of ≥30×10E9/L and ≥20×10E9/L above baseline

  52 weeks

Study Arms (1)

efgartigimod PH20 SC

EXPERIMENTAL

Patients receiving efgartigimod PH20 SC treatment

Biological: efgartigimod PH20 SC

Interventions

efgartigimod PH20 SC BIOLOGICAL

Subcutaneous injection with efgartigimod PH20 SC

Also known as: ARGX-113 PH20 SC

efgartigimod PH20 SC

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 and provide written informed consent (including consent for the use and disclosure of research-related health information), willing and able to comply with the trial protocol procedures (including attending the required trial visits).
• Participants enrolled in the ARGX-113-2004 trial who completed the 24-week trial period.
• Note: If a participant has had an SAE during the ARGX-113-2004 trial, their eligibility should be evaluated by the investigator and the sponsor's trial physician. The decision of enrolling the participant will be evaluated case by case.
• a. Agree to use contraceptives consistent with local regulations and the following:
• Female participants of childbearing potential must have a negative urine pregnancy test at baseline before receiving IMP.
• In addition to the above criteria, for participants who want to continue receiving efgartigimod during an additional 52-week treatment period (only applicable in case efgartigimod is not yet commercially available for patients with primary ITP or available through another patient program for patients with primary ITP), the following criteria apply:
• \. 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).
• \. Participant has completed a 52-week treatment period.

You may not qualify if:

• Introduction or continuation of nonpermitted medications during the ARGX-113-2004 trial (such as anti-CD20 therapy, romiplostim, monoclonal antibodies, Fc fusion proteins, or live/live-attenuated vaccines)
• Use of any other investigational drug or participation in any other investigational trial
• Known hypersensitivity reaction to efgartigimod PH20 SC or any of its excipients
• Pregnant or lactating females and those who intend to become pregnant during the trial or within 90 days after last dose of efgartigimod PH20 SC

Sponsors & Collaborators

• argenx: lead

Study Sites (83)

Investigator Site 0010116

Bentonville, Arkansas, 72758, United States

Location

Investigator site 0010045

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

Location

Investigator Site 0010062

Fort Wayne, Indiana, 46804, United States

Location

Investigator site US0010042

Iowa City, Iowa, 52242, United States

Location

Investigator Site 0010095

Oklahoma City, Oklahoma, 73142, United States

Location

Investigator Site 0540001

Buenos Aires, Argentina

Location

Investigator site 540004

Buenos Aires, Argentina

Location

Investigator Site 0610012

Garran, Australia

Location

Investigator Site 0610003

West Perth, Australia

Location

Investigator site 610005

Westmead, Australia

Location

Investigator Site 3590017

Plovdiv, Bulgaria

Location

Investigator site 0560003

Reñaca, Chile

Location

Investigator site 560002

Santiago, Chile

Location

Investigator site 0560004

Temuco, Chile

Location

Investigator site 860013

Beijing, China

Location

Investigator Site 0860008

Bengbu, China

Location

Investigator site 860055

Huizhou, China

Location

Investigator Site 0860015

Shenzhen, China

Location

Investigator Site 0860001

Tianjin, China

Location

Investigator Site 0860010

Wuhan, China

Location

Investigator Site 0860002

Wuxi, China

Location

Investigator Site 0860011

Zhengzhou, China

Location

Investigator site 860058

Zhenjiang, China

Location

Investigator Site 9950007

Tbilisi, Georgia

Location

Investigator site 9950009

Tbilisi, Georgia

Location

Investigator site 9950011

Tbilisi, Georgia

Location

Investigator site 300008

Athens, Greece

Location

Investigator Site 0300009

Thessaloniki, Greece

Location

Investigator site 3530003

Dublin, Ireland

Location

Investigator site 390043

Ferrara, Italy

Location

Investigator Site 0390032

Milan, Italy

Location

Investigator Site 0390044

Naples, Italy

Location

Investigator site 390041

Naples, Italy

Location

Investigator site JP0810015

Hirakata, 5731191, Japan

Location

Investigator Site 0810017

Iruma, Japan

Location

Investigator Site 0810053

Kanagawa, Japan

Location

Investigator Site 0810051

Kitakyushu, Japan

Location

Investigator site 0810016

Shibukawa, 377-0280, Japan

Location

Investigator site 810023

Shimotsuke, Japan

Location

Investigator Site 0810038

Tama, Japan

Location

Investigator site 9620001

Irbid, Jordan

Location

Investigator site 520002

Aguascalientes, Mexico

Location

Investigator site 640005

Christchurch, New Zealand

Location

Investigator site 0470003

Sarpsborg, 1714, Norway

Location

Investigator site PL0480013

Katowice, 40-519, Poland

Location

Investigator Site 0480026

Nowy Sącz, Poland

Location

Investigator Site 0480037

Skorzewo, Poland

Location

Investigator Site 3510007

Lisbon, Portugal

Location

Investigator site 3510004

Porto, Portugal

Location

Investigator site 3510001

Vila Nova de Gaia, Portugal

Location

Investigator Site 0400005

Bucharest, Romania

Location

Investigator site 400012

Bucharest, Romania

Location

Investigator Site 0400007

Craiova, Romania

Location

Investigator site 0070040

Kirov, Russia

Location

Investigator Site 0070026

Moscow, Russia

Location

Investigator Site 0070038

Nizhny Novgorod, Russia

Location

Investigator Site 0070037

Novosibirsk, Russia

Location

Investigator site 270003

Johannesburg, South Africa

Location

Investigator site 270004

Observatory, South Africa

Location

Investigator site 270001

Pretoria, South Africa

Location

Investigator site 270002

Randburg, South Africa

Location

Investigator site 820004

Seoul, South Korea

Location

Investigator site KO0820007

Seoul, South Korea

Location

Investigator Site 0660002

Bangkok, Thailand

Location

Investigator Site 0660003

Bangkok, Thailand

Location

Investigator site 660005

Bangkok, Thailand

Location

Investigator Site 0660001

Bangkok Noi, Thailand

Location

Investigator site 0660004

Chiang Mai, 50200, Thailand

Location

Investigator site TH0660009

Khon Kaen, Thailand

Location

Investigator site 2610001

Sousse, Tunisia

Location

Investigator site 2160002

Tunis, Tunisia

Location

Investigator Site 0900007

Adapazarı, Turkey (Türkiye)

Location

Investigator Site 0900003

Ankara, Turkey (Türkiye)

Location

Investigator Site 0900008

Ankara, Turkey (Türkiye)

Location

Investigator Site 0900015

Ankara, Turkey (Türkiye)

Location

Investigator site 900004

Izmir, Turkey (Türkiye)

Location

Investigator Site 0900014

Kocaeli, Turkey (Türkiye)

Location

Investigator site 900010

Mersin, Turkey (Türkiye)

Location

Investigator site 0900017

Tekirdağ, 59100, Turkey (Türkiye)

Location

Investigator site 900019

Trabzon, Turkey (Türkiye)

Location

Investigator site 440005

Coventry, United Kingdom

Location

Investigator site UK044041

London, United Kingdom

Location

Investigator site UK0440014

Penzance, TR18 2PF, United Kingdom

Location

MeSH Terms

Conditions

Purpura, Thrombocytopenic, Idiopathic

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: March 15, 2021
• First Posted: March 24, 2021
• Study Start: November 17, 2021
• Primary Completion (Estimated): October 1, 2026
• Study Completion (Estimated): October 1, 2026
• Last Updated: January 12, 2026

Record last verified: 2026-01

Locations

PT (3); AR (2); BU (1); JP (7); PL (3); IE (1); IT (4); NZ (1); KR (2); US (5); CL (3); TU (9); AU (3); RO (3); TH (6); ME (1); GE (3); RU (4); GR (2); JO (1); CN (9); NO (1); ZA (4); GB (3)