Open Label Extension of Efgartigimod in Adults With Post-COVID-19 POTS

Study Overview
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Brief Summary
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The OLE study aims to investigate the safety, efficacy, pharmacodynamics (PD), pharmacokinetics (PK), and immunogenicity of efgartigimod in participants with post-COVID-19 postural orthostatic.

Detailed Description
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Study ARGX-113-2105 is a long-term, single-arm, open-label, multicenter extension of the ARGX-113-2104 study, designed to evaluate the long-term safety of efgartigimod IV in adult patients with PC-POTS. Participants will be enrolled from both active and placebo arms of the ARGX-113-2104 study and will receive efgartigimod IV 10 mg/kg in the extension study without knowledge of their prior treatment arm. To be eligible to enroll in this study, participants must have completed the 24-week treatment period of the ARGX-113-2104 study and must not have permanently discontinued the IMP in that study.

Official Title
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Open-Label Extension Study to Evaluate the Long-term Safety and Efficacy of Efgartigimod in Adult Patients With Post-COVID-19 Postural Orthostatic Tachycardia Syndrome (PC-POTS) Who Completed Study ARGX-113-2104

Conditions
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Post-COVID Postural Orthostatic Tachycardia Syndrome Postural Orthostatic Tachycardia Syndrome

Intervention / Treatment
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* Drug: Efgartigimod


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: The participant has completed the ARGX-113-2104 study without permanent discontinuation of IMP and agrees to directly roll over into the extension study without discontinuation of IMP. The participant signs the informed consent form, and can comply with OLE study (ARGX-113-2105) protocol requirements. The participant agrees to use contraceptives consistent with local regulations regarding the methods of contraception for those participating in clinical studies. Contraceptive requirements are provided. Female participants of childbearing potential must have a negative urine pregnancy test at baseline before receiving IMP. Exclusion Criteria: The participant has a clinically significant condition, based on the judgement of the Study Investigator, eg, laboratory abnormalities, 12-lead ECG readings, concomitant medical disease(s), etc., which may place them at undue risk or confound interpretation of study data. The participant intends to become pregnant or start breastfeeding during the study.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Efgartigimod<br>Receive efgartigimod IV 10mg/kg infusions during a treatment period of 48 weeks | Drug: Efgartigimod<br>* Participants will receive efgartigimod IV 10 mg/kg open label, respectively.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence and severity of AESIs. | adverse events of special interest | Up to 56 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from baseline to week 24 and week 48 in COMPASS 31 (modified) | COMPASS 31 is a self-rated questionnaire with 31 questions in 6 domains | Up to 48 weeks | 
| Change from baseline to week 24 and week 48 in MaPS | The MaPS questionnaire was developed specifically for patients with POTS by investigators at the Skåne University Hospital, Lund University in Malmö, Sweden. The 12-item evaluation score is being evaluated in a case-control study in patients with POTS compared to healthy controls. | Up to 48 weeks | 
| Change from baseline to week 24 and week 48 in PGI-S |  | Up to 48 weeks | 
| PGI-C at week 24 and week 48 |  | Up to 48 weeks | 
| Change from baseline to week 24 and 48 in the PROMIS Fatigue Short Form 8a |  | Up to 48 weeks | 
| Change from baseline to week 24 and 48 in the PROMIS Cognitive Function Short Form 6a |  | Up to 48 weeks | 
| Percent reduction from baseline in total IgG levels over the 48-week treatment period |  | Up to 48 weeks | 
| Efgartigimod serum trough concentrations over the 48-week treatment period |  | Up to 48 weeks | 
| Incidence of ADA against efgartigimod over the 48-week treatment period |  | Up to 48 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Tachycardia Post-COVID, Postural Orthostatic Tachycardia Syndrome efgartigimod