Efficacy profile

The ADAPT phase 3 clinical trial and ADAPT+ open-label extension study design^1,2

The primary endpoint in ADAPT was the proportion of AChRAb+ patients who were MG-ADL responders in the first treatment cycle.¹

MG-ADL responders were defined as:¹

≥2-point reduction in the total MG-ADL score compared to the treatment cycle baseline
Response sustained for ≥4 weeks
First reduction occurring no later than 1 week after the last infusion of the cycle

The secondary endpoint in ADAPT was the proportion of AChRAb+ patients who were QMG responders in the first treatment cycle.¹

QMG responders were defined as:¹

≥3-point reduction in the total QMG score compared to the treatment cycle baseline
Response sustained for ≥4 weeks
First reduction occurring no later than 1 week after the last infusion of the cycle

AChRAb+=acetylcholine receptor antibody-positive; CMI=clinically meaningful improvement; gMG=generalized Myasthenia Gravis; MG-ADL=Myasthenia Gravis Activities of Daily Living; QMG=Quantitative Myasthenia Gravis; Tx=treatment.

†	All patients received an initial cycle, with subsequent cycles administered based on individual clinical evaluation when their MG-ADL score was at least 5 (with >50% MG-ADL non-ocular) and if the patient was an MG-ADL responder, when they no longer had a CMI compared to baseline. The minimum time between treatment cycles, specified by study protocol, was 4 weeks from the last infusion. A maximum of 3 cycles were possible in the 26-week study.²
‡	CMI is defined as having ≥2-point improvement in total MG-ADL score.²
§	All patients received stable doses of their current gMG treatment.²
¶	Participants requiring rescue therapy in ADAPT and in Year 1 of ADAPT+ were discontinued from the study. Participants requiring rescue therapy in Years 2 and 3 of ADAPT+ were not discontinued.²
††	Participants who were eligible for a treatment cycle but could not complete the cycle by Week 26 of ADAPT were also eligible to enroll in ADAPT+.²

The ADAPT trial population represented a range of adults with gMG

The five most prevalent comorbidities at baseline (overall population):^2¶

Hypertension (28%)
Depression (13%)
Diabetes Mellitus (10%)
Osteoporosis (9%)
Gastroesophageal reflux disease (9%)

AChRAb+=acetylcholine receptor antibody-positive; gMG=generalized Myasthenia Gravis; MG-ADL=Myasthenia Gravis Activities of Daily Living; MGFA=Myasthenia Gravis Foundation of America; MuSK=Muscle specific kinase; QMG=Quantitative Myasthenia Gravis; NSIST=non-steroidal immunosuppressant therapy.

†	Data are mean (SD) or n (%).
‡	Includes American Indian or Alaska Native (n=2) and multiple (n=1) for the efgartigimod group, and not reported for the placebo group (n=1).²
§	MG-ADL total score of ≥5 required at screening.²
¶	Conditions shown represent the 5 most prevalent comorbidities reported by investigator at baseline in the ADAPT clinical trial (N=167).²

ADAPT efficacy data

VYVGART^® improved daily function and reduced muscle weakness in significantly more patients vs. placebo²

Significantly more patients treated with VYVGART^® were MG-ADL responders vs. placebo (AChRAb+ patients; primary endpoint)²

MG-ADL responders were defined as:¹

≥2-point reduction in the total MG-ADL score compared to the treatment cycle baseline
Response sustained for ≥4 weeks
First reduction occurring no later than 1 week after the last infusion of the cycle

Significantly more patients treated with VYVGART^® were QMG responders vs. placebo (AChRAb+ patients; secondary endpoint)²

QMG responders were defined as:¹

≥3-point reduction in the total QMG score compared to the treatment cycle baseline
Response sustained for ≥4 weeks
First reduction occurring no later than 1 week after the last infusion of the cycle

AChRAb+=acetylcholine receptor antibody-positive; MG-ADL=Myasthenia Gravis Activities of Daily Living; QMG=Quantitative Myasthenia; Tx=treatment.

Mean change in MG-ADL from baseline following the first treatment cycle in ADAPT (AChRAb+ patients)¹

Adapted from the VYVGART^® Product Monograph.

AChRAb+=acetylcholine receptor antibody-positive; MG-ADL=Myasthenia Gravis Activities of Daily Living; SE=standard error; Tx=treatment.

MG-ADL response with VYVGART^® followed a similar time course as reductions in IgG and AChR Ab levels²

Consistent reductions in total IgG levels and AChR Abs were observed for both the AChRAb+ and overall populations (Cycle 1, AChRAb+)

AChR=acetylcholine receptor; AChRAb+=acetylcholine receptor antibody-positive; IgG=immunoglobulin G; MG-ADL=Myasthenia Gravis Activities of Daily Living.

Patients treated with VYVGART^® achieved higher levels of improvement vs. placebo at Week 4²

Proportion of AChRAb+ patients with increasing thresholds of MG-ADL improvement^2†

Patients treated with VYVGART^® reported up to a 9-point reduction in their MG-ADL scores.^2†

AChRAb+=acetylcholine receptor antibody-positive; MG-ADL=Myasthenia Gravis Activities of Daily Living; Tx=treatment.

† Four weeks after the initial infusion of the first treatment cycle.

Exploratory endpoint: Early response data by Week 2 during the first treatment cycle for patients treated with VYVGART^® (AChRAb+ patients)^2†

Study limitations: Percentage of early responders (response by Week 2) in AChRAb+ patients treated with VYVGART^® was a prespecified descriptive exploratory analysis not controlled for multiplicity and not powered; therefore, data should be interpreted with caution and conclusions cannot be drawn.²

AChRAb+=acetylcholine receptor antibody-positive; MG-ADL=Myasthenia Gravis Activities of Daily Living.

†	Patients were treated with VYVGART^® + current treatment, or placebo + current treatment.²
‡	MG-ADL early response was defined as a ≥2-point reduction in the total MG-ADL score compared to the treatment cycle baseline for at least 4 consecutive weeks during the first treatment cycle (by Week 8), with the first reduction occurring no later than 1 week after the scheduled second infusion (Week 2).²

Exploratory endpoint: Percentage of AChRAb+ patients that achieved Minimal Symptom Expression (MSE)²

The term MSE is used to describe an MG-ADL score of 0 or 12

If a person living with gMG achieves MSE, it means they are experiencing little to no gMG symptoms.

Study limitations: Percentage of anti-AChR antibody positive patients with MSE was a prespecified descriptive exploratory analysis not controlled for multiplicity and not powered; therefore, data should be interpreted with caution and conclusions cannot be drawn.²

AChRAb+=acetylcholine receptor antibody-positive; MG-ADL=Myasthenia Gravis Activities of Daily Living; Tx=treatment.

ADAPT+ efficacy data

VYVGART® demonstrated sustained benefit in patients with gMG in ADAPT+^3†‡

Long-term clinically meaningful improvement in MG-ADL and QMG scores was consistently observed with VYVGART® in ADAPT+ (AChRAb+ patients)^3†‡

>90% of patients had a maximum reduction of ≥2 points (CMI) at any time point in each of the first 10 treatment cycles.^3†

69.4% to 91.3% of patients demonstrated a maximum reduction of ≥3 points (CMI) across the 7 cycles in which QMG was measured.^3†‡

The annualized mean number of cycles was 4.7 cycles per year (median [range] 5.0 [0.5–7.6]).^3§

Study limitations: ADAPT+ is a single arm, open-label study. Endpoint assessments were taken at different (or fewer) timepoints than ADAPT. Results should not directly be compared to ADAPT. Change in MG-ADL and QMG score were prespecified descriptive exploratory analyses not controlled for multiplicity and not powered. Data should be interpreted with caution, and conclusions cannot be drawn.

In ADAPT+, mean total IgG levels decreased with maximum reductions observed at Week 3 and reached baseline between Weeks 7-11³

IgG monitoring is not required before or during VYVGART^® treatment.³

AChRAb+=acetylcholine receptor antibody-positive; CMI=clinically meaningful improvement; gMG=generalized Myasthenia Gravis; IgG=immunoglobulin G; MG-ADL=Myasthenia Gravis Activities of Daily Living; QMG=Quantitative Myasthenia Gravis.

†	Mean change from cycle baseline in MG-ADL total score, by cycle. Only timepoints with ≥3 participants are included.³
‡	Data for Week 11 were not graphed for Cycles 6 and 7 because they were unavailable.⁴
§	In AChR antibody-positive participants (N=95) with ≥1 year of combined follow-up between ADAPT and ADAPT+.³

Consider VYVGART^® for symptomatic AChRAb+ gMG patients prior to IVIg²

AChRAb+=acetylcholine receptor antibody-positive; AChEI=acetylcholine esterase inhibitor; gMG=generalized Myasthenia Gravis; IVIg=intravenous immunoglobulin; NSIST=nonsteroidal immunosuppressive therapy (NSISTs included azathioprine, cyclosporine, cyclophosphamide, methotrexate, mycophenolate mofetil, and tacrolimus); TPE=therapeutic plasma exchange.

†	Stable dose=adequate trial as determined by treating physician of at least 1 AChEIs, corticosteroids, &/or NSISTs in previous 12 months.

Post hoc analyses

Mean change in QMG score sustained for 64 weeks (post hoc analyses of ADAPT and ADAPT+)⁴

Adapted from Dewilde, et al. 2024.

VYVGART^® group spent a substantially greater percentage of time in response across all observed treatment cycles during the ADAPT study.
Percentage of time spent in response in the first 20 weeks was 2.37 times greater (95% CI: 1.49, 3.78) for the VYVGART^® group (p=0.0034 from beta regression model).
Extending the analysis period for efgartigimod to 64 weeks (by incorporating both ADAPT and ADAPT+ data) demonstrated that this effect was sustained in the long-term, with 56% of the time spent in response.

The clinical benefit of VYVGART^® was sustained over repeat treatment cycles and maintained over 64 weeks.⁴

Study limitations: This post hoc analyses of ADAPT and ADAPT+ is exploratory, and therefore, conclusions cannot be drawn.
Data should be interpreted with caution as the assessment frequency and other aspects of the trial design limit the analysis.

AChRAb+=acetylcholine receptor antibody-positive; MG-ADL=Myasthenia Gravis Activities of Daily Living; QMG=Quantitative Myasthenia Gravis.

Mean change in observed MG-ADL total score sustained for 64 weeks (post hoc analyses of ADAPT and ADAPT+)⁴

The clinical benefit of VYVGART^® was sustained over repeat treatment cycles and maintained over 64 weeks.⁴

AChRAb+=acetylcholine receptor antibody-positive; MG-ADL=Myasthenia Gravis Activities of Daily Living; QMG=Quantitative Myasthenia Gravis.

Real-world data

Patients with gMG were able to reduce their OCS usage (US retrospective cohort study; N=316)^6*

OCS usage continued to reduce significantly over 1-year post-VYVGART^® initiation from baseline, while retaining expected MG-ADL response.⁷

More than half (55%) of patients reduced OCS usage by at least ≥5 mg/day on average.
42% of patients were using OCS average daily dose of 5 mg/day or less, and 62% were using OCS average daily dose of 10 mg/day or less

ADD=average daily dose; gMG=generalized Myasthenia Gravis; MG-ADL=Myasthenia Gravis Activities of Daily Living; OCS=oral corticosteroid.

Retrospective cohort study using US medical and pharmacy claims (IQVIA) covering April 2016 to November 2023. The study included 316 patients (≥18 years) with their first VYVGART® claim between January 1 and December 31, 2022, and continuous quarterly claims activity. Patients must have had at least 6 months of VYVGART® usage, evidence of chronic oral corticosteroid usage prior to VYVGART® initiation, and no concomitant use of eculizumab, rituximab, or ravulizumab with VYVGART®. The primary outcome was the change in average daily dose of OCS doses, which were converted to prednisone-equivalent strengths: 1 at 3 months (60-90 days) and 6 months (150-180 days) from baseline.

Consistent MG-ADL responses with VYVGART^® and with comparable results in patients with and without GC tapering (real-world study)⁷

ADD=average daily dose; GC=glucocorticosteroid; MG-ADL=Myasthenia Gravis Activities of Daily Living.

Marked reduction in disease burden with VYVGART® (Italian single-center; real-world experience)^8†

VYVGART^® had a dramatic impact on the course of disease: Rates of hospitalization, ICU admission, and need for IVIg or PLEX were reduced in all patients, except one patient who required immunomodulation.¹

Study limitations: This prospective study is limited by its small sample size at a single center; therefore, caution should be exercised in interpreting the results, and conclusions cannot be drawn.

gMG=generalized Myasthenia Gravis; ICU=intensive care unit; IVIg=intravenous immunoglobulin; PLEX=plasma exchange.

†

Prospective study of 19 patients with gMG administered efgartigimod and followed from November 2021 to January 2023 (14-month follow-up period) at a single center in Milan, Italy. Patients with AChRAb seropositive (AChR-Ab+, n=8; 42.1%) or seronegative gMG were included in the study. VYVGART® is only approved for use in the AchRAb+ population in Canada.⁸

VYVGART^® vs. IVIg: efficacy and safety data in elderly gMG patients (Chinese, single-center study)^9‡

*** p<0.05 is significant

Study limitations: This prospective study is limited by its small sample size and focus on a single treatment cycle of efgartigimod with a short-term (8-week) follow-up, while the ADAPT study required patients to initiate a second treatment cycle following changes in MG-ADL scores. Therefore, caution should be exercised in interpreting the conclusions.

AChRAb+=acetylcholine receptor antibody-positive; ADL=Activities of Daily Living; gMG=generalized Myasthenia Gravis; IVIg=intravenous immunoglobulin; MG-ADL=Myasthenia Gravis Activities of Daily Living.

‡	Single-center, prospective cohort study enrolled elderly patients with AChR-Ab+ gMG from the First Affiliated Hospital of Guangzhou University of Chinese Medicine from January 2024 to July 2024.⁹

References: 1. VYVGART® Product Monograph. argenx. July 17, 2025. 2. Howard JF, et al. 2021. Safety, efficacy, and tolerability of efgartigimod in patients with generalised myasthenia gravis (ADAPT): a multicentre, randomised, placebo-controlled, phase 3 trial Supplementary Appendix. The Lancet Neurology; 20(7). 3. Howard JF, et al. 2024. Long-Term Safety, Tolerability, and Efficacy of Efgartigimod (ADAPT+): Interim Results From a Phase 3 Open-Label Extension Study in Participants With Generalized Myasthenia Gravis. Front Neurol; 14, 1284444. 4. Dewilde S, et al. 2024. Post-hoc analyses from the ADAPT clinical study demonstrate aggregate sustained benefit of Efgartigimod in generalized myasthenia gravis. J Neurol Sci; 2024;466:123264. 5. CADTH reimbursement review - efgartigimod alfa. April 2024; V4(4). Available at: https://www.cda-amc.ca/sites/default/files/DRR/2024/SR0782-Vyvgart.pdf 6. Ruck T, et al. 2024, June 29-July 2. Real world reduction in oral corticosteroid utilization following efgartigimod initiation [Poster Presentation]. Presented at: 10^th EAN Congress 2024, Helenski, Finland. 7. Goyal N, et al. 2024, October 15-18. Real-World Reduction in Oral Glucocorticoid Utilization at 1-Year Following Efgartigimod Initiation [Poster Presentation]. Presented at: American Association of Neuromuscular & Electrodiagnostic Medicine (AANEM) Annual Meeting, Savana, Georgia, United States. 8. Frangiamore R, et al. 2023 Efgartigimod in generalized myasthenia gravis: A real‐life experience at a national reference center. Eur J Neurol. 31(4):e16189. 9. Zhang C, et al. 2025. The efficacy and safety between efgartigimod and intravenous immunoglobulin in elderly generalized myasthenia gravis patients. Clin Immunol. 274:110457.

The ADAPT trial population represented a range of adults with gMG

The five most prevalent comorbidities at baseline (overall population):2¶

ADAPT efficacy data

VYVGART® improved daily function and reduced muscle weakness in significantly more patients vs. placebo2

Significantly more patients treated with VYVGART® were MG-ADL responders vs. placebo (AChRAb+ patients; primary endpoint)2

Significantly more patients treated with VYVGART® were QMG responders vs. placebo (AChRAb+ patients; secondary endpoint)2

Mean change in MG-ADL from baseline following the first treatment cycle in ADAPT (AChRAb+ patients)1

MG-ADL response with VYVGART® followed a similar time course as reductions in IgG and AChR Ab levels2

Patients treated with VYVGART® achieved higher levels of improvement vs. placebo at Week 42

Proportion of AChRAb+ patients with increasing thresholds of MG-ADL improvement2†

Exploratory endpoint: Early response data by Week 2 during the first treatment cycle for patients treated with VYVGART® (AChRAb+ patients)2†

Exploratory endpoint: Percentage of AChRAb+ patients that achieved Minimal Symptom Expression (MSE)2