Study to Evaluate the Safety and Efficacy of Efgartigimod (ARGX-113) PH20 Subcutaneous in Adult Patients With Primary Immune Thrombocytopenia

Overview

Sponsor-declared trial summary

Key facts

Sponsor

Argenx

Participant type

Patients

Age range

18-64 years, 65+ years

Gender

Male and Female

Therapeutic area

Diseases [C] - Hemic and Lymphatic Diseases [C15]

Trial duration

26 Apr 2022 → ongoing

Decision date (initial)

2024-07-19

Transition trial

Yes

Low-intervention

No

Rare-disease indication

Yes

Vulnerable population

Yes

Funding sources

argenx BV

External identifiers

EU CT number

2024-513147-90-00

EudraCT number

2020-004033-20

Trial design

CTIS Part I — objectives, methods, condition coding

Main objective

Scope: Pharmacodynamic, Others, Pharmacokinetic, Safety, Efficacy

To evaluate the safety and tolerability of efgartigimod PH20 SC in adult patients with primary ITP

Secondary objectives 8

1. First 52-week treatment period only: To evaluate the efficacy of efgartigimod PH20 SC on overall platelet count response
2. First 52-week treatment period only: To evaluate the use of rescue treatment and reduction in concurrent ITP therapy while receiving treatment with efgartigimod PH20 SC
3. First 52-week treatment period only: To evaluate the incidence and severity of bleeding events while receiving treatment with efgartigimod PH20 SC
4. First 52-week treatment period only: To assess the PK of efgartigimod PH20 SC
5. First 52-week treatment period only: To evaluate the effects of efgartigimod PH20 SC treatment on quality of life (QoL) measures and patient-reported outcomes (PRO)
6. First 52-week treatment period only: To assess the PD effects of efgartigimod PH20 SC
7. First 52-week treatment period only: To evaluate the feasibility of self-administration of efgartigimod PH20 SC
8. First 52-week treatment period and additional 52-week treatment periods: To assess the immunogenicity of efgartigimod

Conditions and MedDRA coding

Primary Immune Thrombocytopenia

Regulatory references

Scientific advice from competent authorities

European Medicines Agency

EMA paediatric investigation plan (PIP)

EMEA-002597-PIP04-21

Plan to share IPD

No

Eligibility criteria

Principal inclusion / exclusion criteria as submitted by sponsor

Inclusion criteria 6

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. The decision of enrolling the participant will be evaluated case by case.
3. Agree to use contraceptive measures consistent with local regulations and the following: Female participants of childbearing potential must have a negative urine pregnancy test at baseline before receiving IMP
4. 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 program for patients with primary ITP), the following criteria apply:
5. 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).
6. Participant has completed a 52-week treatment period.

Exclusion criteria 4

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

Endpoints

Primary and secondary outcome measures (English text)

Primary endpoints 2

1. Incidence, frequency, and severity of adverse events (AEs), AEs of special interest (AESIs), and serious AEs (SAEs)
2. Vital signs, electrocardiogram (ECG), and laboratory safety evaluations

Secondary endpoints 21

1. First 52-week treatment period only: Extent of disease control defined as the percentage of weeks in the trial with platelet counts of ≥50×10^9/L
2. First 52-week treatment period only: Proportion of participants 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
3. First 52-week treatment period only: Mean change from baseline in platelet count at each visit
4. First 52-week treatment period only: For participants rolling over from the ARGX-113-2004 trial with a platelet count of <30×10^9/L: time to response defined as the time to achieve 2 consecutive platelet counts of ≥50×10^9/L
5. First 52-week treatment period only: The percentage of weeks in the trial with platelet counts of ≥ 30×10^9/L and ≥20×10^9/L above baseline
6. First 52-week treatment period only: In patients with a baseline platelet count of <15×10^9/L in the current trial (ARGX-113-2005), the percentage of weeks in the trial with platelet counts of ≥30×10^9/L and ≥20×10^9/L above baseline
7. First 52-week treatment period only: In participants with the first exposure to efgartigimod PH20 SC, the proportion of participants who achieve a sustained platelet response defined as achieving platelet counts of ≥50×10^9/L for at least 4 of the 6 visits between week 19 and week 24
8. First 52-week treatment period only: In participants with the first exposure to efgartigimod PH20 SC, the proportion of participants achieving platelet counts of ≥50×10^9/L for at least 6 of the 8 visits between week 17 and week 24
9. First 52-week treatment period only: Proportion of participants for whom dose and/or frequency of concurrent ITP therapies have been reduced compared to baseline
10. First 52-week treatment period only: Rate of receipt of rescue therapy (rescue per participant per month)
11. First 52-week treatment period only: Incidence and severity of the World Health Organization (WHO)-classified bleeding events
12. First 52-week treatment period only: Serum efgartigimod concentration observed predose (Ctrough)
13. First 52-week treatment period only: Change from baseline in PRO (Functional Assessment of Chronic Illness Therapy Fatigue Scale [FACIT-fatigue], Functional Assessment of Cancer Therapy questionnaire-Th6 [FACT-Th6]), QoL (Short Form-36 [SF-36]), and ITP-Patient Assessment Questionnaire [ITP-PAQ] at planned visits
14. First 52-week treatment period only: PD markers: total IgG
15. First 52-week treatment period only: Number and percentage of participants who performed self-administration at home over time
16. First 52-week treatment period only: Number and percentage of caregivers who administered the injection to the participant at home over time
17. First 52-week treatment period only: Number of training visits needed for the participant or caregiver to become competent in the (self-)administration of efgartigimod PH20 SC
18. First 52-week treatment period only: Number and percentage of self-administrations or caregiver-supported administrations at home First 52-week treatment period and additional 52-week treatment periods
19. First 52-week treatment period and additional 52-week treatment periods: Incidence and prevalence of antibodies to efgartigimod
20. First 52-week treatment period and additional 52-week treatment periods: Titers of antibodies to efgartigimod
21. First 52-week treatment period and additional 52-week treatment periods: Presence of neutralizing antibodies (NAb) against efgartigimod

Investigational products

Investigational medicinal products (IMPs), comparators, placebo, auxiliary

Test 1

Sponsors and contacts

Sponsor organisations, regulatory contacts, third parties

Argenx

Sponsor organisation

Argenx

Address

Industriepark-Zwijnaarde 7

City

Gent

Postcode

9052

Country

Belgium

Scientific contact point

Organisation

Argenx

Contact name

Regulatory

Public contact point

Organisation

Argenx

Contact name

Regulatory

Third parties 10

Locations

6 EU/EEA countries · 9 investigational sites

By country

Investigational sites

Country notifications

Trial-start, recruitment-start, end and early-termination notifications submitted per Member State

Results and documents

Annex IV summary of results, Annex V layperson summary, and all documents registered in CTIS for this trial

Documents 18 files

Public protocol annexes, IB summaries, regulatory submissions and post-authorisation documents registered in CTIS.

Application history

7 submissions — initial application plus substantial / non-substantial modifications