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

Phase 3

Active, not recruiting

• Conditions: Primary Immune Thrombocytopenia
• Interventions: Biological: efgartigimod PH20 SC

• Registration Number: NCT04812925
• Lead Sponsor: argenx

Brief Summary

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

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2021-03-15
• Study First Submitted QC: 2021-03-19
• Study First Posted: 2021-03-24
• Study Start: 2021-11-17
• Status Verified: 2024-12
• Last Update Submitted: 2024-12-02
• Last Update Posted: 2024-12-04
• Primary Completion: 2026-10-01
• Study Completion: 2026-10-01

Recruitment & Eligibility

• Status: ACTIVE_NOT_RECRUITING
• Sex: All
• Target Recruitment: 173

Inclusion Criteria

1. 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).
2. 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.

3a. 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:

4. 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).

5. Participant has completed a 52-week treatment period.

Exclusion criteria:

1. 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)
2. Use of any other investigational drug or participation in any other investigational trial
3. Known hypersensitivity reaction to efgartigimod PH20 SC or any of its excipients
4. 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

Exclusion Criteria

Not provided

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
efgartigimod PH20 SC	efgartigimod PH20 SC	Patients receiving efgartigimod PH20 SC treatment

Primary Outcome Measures

Name	Time	Method
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 Outcome Measures

Name	Time	Method
Severity of the World Health Organization (WHO)-classified bleeding events	52 weeks
Mean change from baseline in platelet count at each visit	52 weeks
Change from baseline in PRO (QoL (Short Form-36 [SF-36]) at planned visits	52 weeks
Number of patients who performed self-administration at home over time	52 weeks
Percentage of caregivers who administered the injection to the patient at home over time	52 weeks
In patients with a baseline platelet count of <15×10E9/L in the current trial (ARGX-113-2005), the percentage of weeks in the trial with platelet counts of ≥30×10E9/L and ≥20×10E9/L above baseline	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
In patients with the first exposure to efgartigimod PH20 SC, the proportion of patients achieving platelet counts of ≥50×10E9/L for at least 6 of the 8 visits between week 17 and week 24	7 weeks (week 17-24)
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
The percentage of weeks in the trial with platelet counts of ≥30×10E9/L and ≥20×10E9/L above baseline	52 weeks
In patients with the first exposure to efgartigimod PH20 SC, the proportion of patients who achieve a sustained platelet response defined as achieving platelet counts of ≥50×10E9/L for at least 4 of the 6 visits between week 19 and week 24	5 weeks (week 19-24)
Rate of receipt of rescue therapy (rescue per patient per month)	52 weeks
Percentage of patients who performed self-administration at home over time	52 weeks
Proportion of patients for whom dose and/or frequency of concurrent ITP therapies have been reduced compared to baseline	52 weeks
Number of caregivers who administered the injection to the patient at home over time	52 weeks
Number of self- or caregiver-supported administrations at home	52 weeks
Presence of neutralizing antibodies (NAb) against efgartigimod	216 weeks
Incidence of the World Health Organization (WHO)-classified bleeding events	52 weeks
Change from baseline in PRO (Functional Assessment of Chronic Illness Therapy Fatigue Scale [FACIT-fatigue]) at planned visits	52 weeks
Pharmacodynamics markers: total IgG	52 weeks
Number of training visits needed for the participant or caregiver to be competent to start administering efgartigimod PH20 SC	52 weeks
Percentage of self- or caregiver-supported administrations at home	52 weeks
Incidence and prevalence of antibodies to efgartigimod	216 weeks
Titers of antibodies to efgartigimod	216 weeks
Serum efgartigimod concentration observed predose (Ctrough)	52 weeks
Change from baseline in PRO (Functional Assessment of Cancer Therapy questionnaire-Th6 [FACT-Th6]) at planned visits	52 weeks

Trial Locations

Locations (83)

Investigator Site 0010116; 🇺🇸 Bentonville, Arkansas, United States

Investigator site 0010045; 🇺🇸 Washington, District of Columbia, United States

Investigator Site 0010062; 🇺🇸 Fort Wayne, Indiana, United States

Investigator site US0010042; 🇺🇸 Iowa City, Iowa, United States

Investigator Site 0010095; 🇺🇸 Oklahoma City, Oklahoma, United States

Investigator Site 0540001; 🇦🇷 Buenos Aires, Argentina

Investigator site 540004; 🇦🇷 Buenos Aires, Argentina

Investigator Site 0610012; 🇦🇺 Garran, Australia

Investigator Site 0610003; 🇦🇺 West Perth, Australia

Investigator site 610005; 🇦🇺 Westmead, Australia

Scroll for more (73 remaining)