Clinical data

Explore the data behind VYVGART from the pivotal clinical trial, including improvement in daily function and reduction in muscle weakness.

PRIMARY ENDPOINT

VYVGART improved daily function in significantly more patients vs placebo1,2

The primary endpoint was the percentage of anti-AChR antibody positive patients who were MG-ADL responders, defined as a patient with 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 last infusion of the cycle.1

AChR=acetylcholine receptor; MG-ADL=Myasthenia Gravis Activities of Daily Living; Tx=treatment.

MSE
EXPLORATORY ENDPOINT

Exploratory endpoint: MG-ADL data for Minimal Symptom Expression (MSE)2,3*

Percent of patients with MSE. MSE is characterized by an MG-ADL total score of 0 or 1 out of a maximum of 24. Patients were evaluated at any visit during the first treatment cycle.

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.

*Clinical trial data for anti-AChR antibody positive patients. Patients were treated with VYVGART + current treatment or placebo + current treatment.

MSE evaluation occurred at any visit from week 1 through week 26.
AChR=acetylcholine receptor; MG-ADL=Myasthenia Gravis Activities of Daily Living; Tx=treatment.

Secondary Endpoint
SECONDARY ENDPOINT

VYVGART reduced muscle weakness in significantly more patients vs placebo1,2

The secondary endpoint was the percentage of anti-AChR antibody positive patients who were QMG responders, defined as a patient with a ≥3-point reduction in the total QMG 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 last infusion of the cycle.1

AChR=acetylcholine receptor; QMG=Quantitative Myasthenia Gravis; Tx=treatment.

IMPROVEMENT IN DAILY FUNCTION

VYVGART demonstrated greater improvement in daily function vs placebo at week 41*

MG-ADL skyline

*Clinical trial data from patients who were anti-AChR antibody positive.

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

AChR=acetylcholine receptor; MG-ADL=Myasthenia Gravis Activities of Daily Living; Tx=treatment.

REDUCTION IN MUSCLE WEAKNESS

VYVGART demonstrated greater reduction in muscle weakness vs placebo at week 41*

QMG Skyline

*Clinical trial data from patients who were anti-AChR antibody positive.

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

AChR=acetylcholine receptor; QMG=Quantitative Myasthenia Gravis; Tx=treatment.

EXPLORATORY ENDPOINT

Exploratory endpoint: early response data for patients on VYVGART2,3*

84%

(n=37/44)

of patients treated with VYVGART who were MG-ADL responders showed a response by week 2 in the first treatment cycle. These patients were considered early responders.

Of the 19 placebo-treated patients who met the primary endpoint, 16 (84%) showed a response by week 2.

Study Limitations: Percentage of early responders (response by week 2) in anti-AChR antibody positive 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.

*Clinical trial data for anti-AChR antibody positive patients. Patients were treated with VYVGART + current treatment or placebo + current treatment.

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 one week after the scheduled second infusion (week 2).

AChR=acetylcholine receptor; MG-ADL=Myasthenia Gravis Activities of Daily Living.

POST-HOC ANALYSIS

Post-hoc analysis: MG-ADL response data across first or second treatment cycles for patients on VYVGART3*

44/65 patients treated with VYVGART had a response during the first treatment cycle vs 19/64 treated with placebo. Of the 21 patients treated with VYVGART who did not have a response during the first treatment cycle, 7 were responders during the second treatment cycle. Of the 45 patients treated with placebo who did not have a response during the first treatment cycle, 9 were responders during the second treatment cycle.†‡

Study Limitations: The MG-ADL responder data across first or second treatment cycles was a post-hoc analysis based on a prespecified exploratory endpoint not controlled for multiplicity and not powered; therefore, data should be interpreted with caution and conclusions cannot be drawn.

*Clinical trial data from patients who were anti-AChR antibody positive. Patients were treated with VYVGART + current treatment or placebo + current treatment.

MG-ADL 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 last infusion of the cycle.

The same measure for response was applied to the analysis during the second treatment cycle.

AChR=acetylcholine receptor; MG-ADL=Myasthenia Gravis Activities of Daily Living; Tx=treatment.

Infection

VYVGART may increase the risk of infection. The most common infections observed in Study 1 were urinary tract infection (10% for VYVGART vs 5% for placebo) and respiratory tract infection (33% for VYVGART vs 29% for placebo). Patients on VYVGART vs placebo had below normal levels for white blood cell counts (12% vs 5%, respectively), lymphocyte counts (28% vs 19%, respectively), and neutrophil counts (13% vs 6%, respectively). The majority of infections and hematologic abnormalities were mild to moderate in severity. Delay VYVGART administration in patients with an active infection until the infection is resolved; monitor for clinical signs and symptoms of infections. If serious infection occurs, administer appropriate treatment and consider withholding VYVGART until the infection has resolved.

Immunization

Immunization with vaccines during VYVGART treatment has not been studied; the safety with live or live-attenuated vaccines and the response to immunization with any vaccine are unknown. Because VYVGART causes a reduction in immunoglobulin G (IgG) levels, vaccination with live-attenuated or live vaccines is not recommended during VYVGART treatment. Evaluate the need to administer age-appropriate vaccines according to immunization guidelines before initiation of a new treatment cycle with VYVGART.

Hypersensitivity Reactions

Hypersensitivity reactions, including rash, angioedema, and dyspnea, were observed with VYVGART. In clinical trials, hypersensitivity reactions were mild or moderate, occurred within 1 hour to 3 weeks of administration, and did not lead to treatment discontinuation. Monitor patients during administration and for 1 hour thereafter for clinical signs and symptoms of hypersensitivity reactions. If a hypersensitivity reaction occurs during administration, discontinue VYVGART infusion and institute appropriate supportive measures if needed.

ADVERSE REACTIONS

The most common (≥10%) adverse reactions with VYVGART were respiratory tract infection, headache, and urinary tract infection.

USE IN SPECIFIC POPULATIONS

Pregnancy

As VYVGART is expected to reduce maternal IgG antibody levels, reduction in passive protection to the newborn is anticipated. Risks and benefits should be considered prior to administering live or live-attenuated vaccines to infants exposed to VYVGART in utero.

Lactation

There is no information regarding the presence of VYVGART in human milk, the effects on the breastfed infant, or the effects on milk production. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for VYVGART and any potential adverse effects on the breastfed infant from VYVGART or from the underlying maternal condition.

INDICATION

VYVGART® (efgartigimod alfa-fcab) is indicated for the treatment of generalized myasthenia gravis in adult patients who are anti-acetylcholine receptor (AChR) antibody positive.

Please see the full Prescribing Information.

You may report side effects to the US Food and Drug Administration by visiting http://www.fda.gov/medwatch or calling 1-800-FDA-1088. You may also report side effects to argenx US, Inc, at 1-833-argx411 (1-833-274-9411).

Infection

VYVGART may increase the risk of infection. The most common infections observed in Study 1 were urinary tract infection (10% for VYVGART vs 5% for placebo) and respiratory tract infection (33% for VYVGART vs 29% for placebo). Patients on VYVGART vs placebo had below normal levels for white blood cell counts (12% vs 5%, respectively), lymphocyte counts (28% vs 19%, respectively), and neutrophil counts (13% vs 6%, respectively). The majority of infections and hematologic abnormalities were mild to moderate in severity. Delay VYVGART administration in patients with an active infection until the infection is resolved; monitor for clinical signs and symptoms of infections. If serious infection occurs, administer appropriate treatment and consider withholding VYVGART until the infection has resolved.

Immunization

Immunization with vaccines during VYVGART treatment has not been studied; the safety with live or live-attenuated vaccines and the response to immunization with any vaccine are unknown. Because VYVGART causes a reduction in immunoglobulin G (IgG) levels, vaccination with live-attenuated or live vaccines is not recommended during VYVGART treatment. Evaluate the need to administer age-appropriate vaccines according to immunization guidelines before initiation of a new treatment cycle with VYVGART.

Hypersensitivity Reactions

Hypersensitivity reactions, including rash, angioedema, and dyspnea, were observed with VYVGART. In clinical trials, hypersensitivity reactions were mild or moderate, occurred within 1 hour to 3 weeks of administration, and did not lead to treatment discontinuation. Monitor patients during administration and for 1 hour thereafter for clinical signs and symptoms of hypersensitivity reactions. If a hypersensitivity reaction occurs during administration, discontinue VYVGART infusion and institute appropriate supportive measures if needed.

ADVERSE REACTIONS

The most common (≥10%) adverse reactions with VYVGART were respiratory tract infection, headache, and urinary tract infection.

USE IN SPECIFIC POPULATIONS

Pregnancy

As VYVGART is expected to reduce maternal IgG antibody levels, reduction in passive protection to the newborn is anticipated. Risks and benefits should be considered prior to administering live or live-attenuated vaccines to infants exposed to VYVGART in utero.

Lactation

There is no information regarding the presence of VYVGART in human milk, the effects on the breastfed infant, or the effects on milk production. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for VYVGART and any potential adverse effects on the breastfed infant from VYVGART or from the underlying maternal condition.

INDICATION

VYVGART® (efgartigimod alfa-fcab) is indicated for the treatment of generalized myasthenia gravis in adult patients who are anti-acetylcholine receptor (AChR) antibody positive.

Please see the full Prescribing Information.

You may report side effects to the US Food and Drug Administration by visiting http://www.fda.gov/medwatch or calling 1-800-FDA-1088. You may also report side effects to argenx US, Inc, at 1-833-argx411 (1-833-274-9411).

References: 1. VYVGART. Prescribing information. argenx US Inc; 2022. 2. Howard JF Jr et al. Lancet Neurol. 2021;20(7):526-536. doi:10.1016/S1474-4422(21)00159-9 3. Data on file, argenx US Inc. May 2023. 4. Wolfe GI et al. Neurology. 1999;52(7):1487-1489. doi:10.1212/wnl.52.7.1487