A Long-Term, Single-Arm, Open-label, Multicenter Phase 3 Study to Evaluate the Safety and Tolerability of Multiple Subcutaneous Injections of Efgartigimod PH20 SC in Patients With Generalized Myasthenia Gravis

argenx47 sites in 12 countries184 target enrollmentApril 26, 2021

ConditionsGeneralized Myasthenia Gravis

Interventionsefgartigimod PH20 SC

Drugsefgartigimod PH20 SC

Overview

Phase: Phase 3
Intervention: efgartigimod PH20 SC
Conditions: Generalized Myasthenia Gravis
Sponsor: argenx
Enrollment: 184
Locations: 47
Primary Endpoint: Incidence of Adverse Events of Special Interest (AESI)
Status: Completed
Last Updated: 3 months ago

Overview Investigators Eligibility Criteria Arms & Interventions Outcomes Sites Similar Trials

Overview

Brief Summary

The purpose of this study is to evaluate the long-term safety and tolerability of efgartigimod PH20 SC 1000 mg, and the clinical efficacy, PD, pharmacokinetics (PK), immunogenicity, impact on the quality of life (QoL) of the participants, treatment satisfaction, and administration method preference, and the feasibility of self- and caregiver-supported administration of the SC injection.

Treatment duration: 3-week treatment periods, repeated as needed with at least 28 days in between treatment periods

Health measurements: total levels of immunoglobulin G (IgG), Acetylcholine receptor binding autoantibodies (AChR-Ab) levels, Myasthenia Gravis Activities of Daly Living (MG-ADL).

Registry

clinicaltrials.gov

Start Date

April 26, 2021

End Date

December 31, 2024

Last Updated

3 months ago

Study Type

Interventional

Study Design

Single Group

Sex

All

Investigators

Sponsor

argenx

Responsible Party

Sponsor

Eligibility Criteria

Inclusion Criteria

•Must be capable of giving signed informed consent, which includes compliance with the requirements and restrictions listed in the informed consent form (ICF) and in this protocol.
•Previously participated in antecedent studies ARGX-113-2001 or ARGX-113-1705 and are eligible for roll over.
•Contraceptive use by men and women should be consistent with local regulations regarding the methods of contraception for those participating in clinical studies and:
•Women of Child bearing potential (WOCBP) must have a negative urine pregnancy test at baseline before investigational medicinal product (IMP) can be administered.

Exclusion Criteria

•The participant was discontinued early from studies ARGX-113-2001 or ARGX-113-1705, unless the reason for discontinuation from study ARGX-113-1705 was to roll over into study ARGX-113-
•a. Participants who, in the investigator's judgment, are not benefiting from efgartigimod IV in study ARGX-113-1705 Part B are not eligible for roll over into ARGX-113-
•Are pregnant or lactating, or intend to become pregnant during the study or within 90 days after the last dose of investigational medicinal product (IMP)
•Has any of the following medical conditions:
•Clinically significant uncontrolled chronic bacterial, viral, or fungal infection at roll-over
•Any other known autoimmune disease that, in the opinion of the investigator, would interfere with accurate assessment of clinical symptoms of myasthenia gravis or put the participant at undue risk
•History of malignancy unless deemed cured by adequate treatment with no evidence of reoccurrence for ≥3 years before the first administration of investigational medicinal product (IMP).
•Participants with the following cancers can be included at any time:
•adequately treated basal cell or squamous cell skin cancer
•carcinoma in situ of the cervix

Arms & Interventions

efgartigimod PH20 SC

Patients receiving efgartigimod PH20 subcutaneous (SC) treatment

Intervention: efgartigimod PH20 SC

Outcomes

Primary Outcomes

Incidence of Adverse Events of Special Interest (AESI)

Time Frame: Up to 3.5 years

Incidence and severity of Adverse Events (AEs)

Time Frame: Up to 3.5 years

Incidence of Serious Adverse Events (SAEs)

Time Frame: Up to 3.5 years

Secondary Outcomes

Number of training visits needed for the participant or caregiver to be competent to start administering efgartigimod PH20 SC(Up to 3.5 years)
Percentage of caregivers who administered the injection to the participant at home over time by cycle(Up to 3.5 years)
Myasthenia Gravis Activities of Daily Living (MG-ADL) total score changes from baseline(Up to 3.5 years)
Percentage change in levels of total immunoglobulin G (IgG) from baseline(Up to 3.5 years)
Cycle baseline over time by cycle (for total immunoglobulin G (IgG)(Up to 3.5 years)
Percentage change of anti-acetylcholine receptor antibodies (AChR-Ab) from baseline(Up to 3.5 years)
Cycle baseline over time by cycle (for MG-ADL)(Up to 3.5 years)
Number of participants who performed self-administration at home over time by cycle(Up to 3.5 years)
Cycle baseline over time by cycle in AChR-Ab seropositive participants (for acetylcholine receptor binding autoantibodies (AChR-Ab))(Up to 3.5 years)
Prevalence of anti-drug antibodies (ADAs) to efgartigimod over time(Up to 3.5 years)
Incidence of neutralizing antibodies (NAbs) against efgartigimod over time(Up to 3.5 years)
Incidence of ADAs to rHuPH20 over time(Up to 3.5 years)
Incidence of NAbs against rHuPH20 over time(Up to 3.5 years)
EQ-5D-5L responses over time by cycle(Up to 3.5 years)
Percentage of self- or caregiver-supported study drug administration among all study treatment visits at home(Up to 3.5 years)
Efgartigimod serum concentrations(Up to 3.5 years)
Prevalence of NAbs against rHuPH20 over time(Up to 3.5 years)
Number of self- or caregiver-supported study drug administration among all study treatment visits at home(Up to 3.5 years)
Incidence of anti-drug antibodies (ADAs) to efgartigimod over time(Up to 3.5 years)
Cycle baseline by cycle (for MG-QoL15r)(Up to 3.5 years)
Changes in EuroQoL 5 Dimensions 5-Level (EQ-5D-5L) visual analog scale (VAS) score from baseline(Up to 3.5 years)
Prevalence of neutralizing antibodies (NAbs) against efgartigimod over time(Up to 3.5 years)
Prevalence of ADAs to rHuPH20 over time(Up to 3.5 years)
Cycle baseline by cycle (for EQ-5D-5L)(Up to 3.5 years)
Number of caregivers who administered the injection to the participant at home over time by cycle(Up to 3.5 years)
Changes in total Myasthenia Gravis Quality of Life Questionnaire (15-item scale revised) (MG-QoL15r) from baseline(Up to 3.5 years)
Percentage of participants who performed self-administration at home over time by cycle(Up to 3.5 years)