# Post Hoc, Sex‐Specific Subgroup Analysis of Efgartigimod in Patients With Generalized Myasthenia Gravis From the ADAPT Trial: A Sex and Gender Equity in Research (SAGER) Guidelines Approach

## TL;DR

This study analyzed how a drug called efgartigimod affects men and women with a muscle disease called generalized myasthenia gravis, finding similar results in both sexes.

## Contribution

The study provides new evidence on sex-specific treatment outcomes for generalized myasthenia gravis using efgartigimod, following sex and gender equity research guidelines.

## Key findings

- Efgartigimod showed similar efficacy in improving symptoms in both male and female patients with generalized myasthenia gravis.
- Quality of life improvements and safety profiles were consistent across sexes in the efgartigimod-treated group.
- Baseline disease severity and patient characteristics differed between male and female participants.

## Abstract

Sex‐specific differences in myasthenia gravis (MG) are widely acknowledged, yet data on sex‐based outcomes of MG treatment are scarce. In accordance with Sex and Gender Equity in Research guidelines, this post hoc analysis assessed potential sex‐specific differences in treatment outcomes in acetylcholine receptor antibody–positive (AChR‐Ab+) generalized (g)MG participants in the Phase 3 ADAPT trial (NCT03669588).

Participants received four once‐weekly efgartigimod infusions (10 mg/kg) or placebo per cycle. Endpoints (primary: proportion of Myasthenia Gravis Activities of Daily Living (MG‐ADL) responders (Cycle 1); secondary: proportion of Quantitative Myasthenia Gravis (QMG) and early (Cycle 1) MG‐ADL responders, and time with clinically meaningful improvements in MG‐ADL score; additional: quality of life outcomes, pharmacodynamics) were assessed according to sex.

Females were younger (mean age: 42.9 vs. 54.8 years), more likely to have undergone thymectomy (65.1% [56/86] vs. 44.2% [19/43]), and had higher baseline QMG scores (16.3 vs. 14.3) compared with males. Efgartigimod demonstrated homogeneous effects between sexes, with no significant difference in proportions of MG‐ADL (p = 0.7014), early (Cycle 1) MG‐ADL (p = 1.00), or QMG responders (p = 0.1595). Improvements in quality‐of‐life assessments, rates of minimal symptom expression, and mean total immunoglobulin G reductions (Cycle 1) were greater with efgartigimod verso placebo in females and males. Efgartigimod was well tolerated, with similar safety profiles across sexes.

In ADAPT, efgartigimod‐treated female and male AChR‐Ab+ gMG patients had similar efficacy and safety outcomes. These data provide valuable insight for clinicians, given the established sex differences in MG disease course and treatment responses.

Trial Registration: The ADAPT trial is registered on ClinicalTrials.gov (NCT03669588).