Why minimal symptom expression matters: raising the bar for people living with myasthenia gravis

For people living with myasthenia gravis (MG), a rare, chronic autoimmune disease characterized by fluctuating muscle weakness and fatigue, clinical improvements measured in practice may not always capture the day-to-day reality of living well with the condition.

Throughout my career, and particularly during my years working alongside the MG community, I have witnessed advances in how MG is diagnosed, managed and treated. Yet what has stayed with me most is not a clinical result or a study outcome, but the stories patients share about the impact of the disease on their everyday lives.

Clinical measures are essential. They help us understand disease activity, assess treatment effects and guide medical decision-making. But they do not always capture the full reality of living with MG. The experiences that matter most to patients often extend beyond what can be measured in a clinic.

Looking beyond symptom control

Current treatment approaches for MG focus on reducing disease activity, controlling symptoms, and helping patients maintain daily functioning and quality of life. These goals remain fundamental to meaningfully managing the impact of MG.

At the same time, conversations with people living with MG continually remind me that success is often defined in more personal terms. It may mean enjoying a meal without difficulty swallowing, speaking confidently through an entire conversation, or making plans without worrying whether symptoms will unexpectedly interfere.

These experiences may appear ordinary to many, but for someone living with MG they can represent a profound difference in daily life. Over the years, I have heard patients describe these moments not as milestones, but as pieces of normal life that many of us take for granted. Those conversations have reinforced for me how differently clinicians and patients can sometimes define success.

As medical professionals, researchers and innovators, we have a responsibility to understand and value these perspectives. Doing so helps ensure that our treatment goals reflect not only what is clinically important, but also what is meaningful to patients.

What is Minimal Symptom Expression?

Minimal Symptom Expression (MSE) is defined as a Myasthenia Gravis Activities of Daily Living (MG-ADL) score of 0 or 1, a definition increasingly recognized and applied in MG research and clinical studies.

In practical terms, MSE means living with minimal or no symptoms and little impact on daily life.

What makes MSE particularly meaningful is its focus on the patient experience. Rather than concentrating solely on clinician-assessed measures of disease activity, it reflects how people experience MG in their everyday lives. MSE has increasingly been described as a patient-centered outcome because it is based on the Myasthenia Gravis Activities of Daily Living (MG-ADL) questionnaire, a patient-reported measure of disease impact.

A more patient-centered measure of success

For me, the significance of MSE extends beyond its definition as a clinical endpoint.

It reflects an evolution in how we think about success in MG. Rather than asking only whether treatment has improved symptoms, we can also ask whether it has enabled someone to participate more fully in the activities that matter most to them.

This shift encourages a more ambitious vision for patient care. It challenges us to consider whether people living with MG can achieve greater freedom, confidence and participation in everyday life, with fewer reminders of their condition.

Importantly, it also reinforces the principle that patients should help define what meaningful improvement looks like.

Why does patient experience matter in MG?

As Chief Medical Officer at UCB, I believe that scientific rigor and patient experience must go hand in hand.

Robust data guides our decisions, informs treatment development and helps advance standards of care. Yet data alone is not enough. The ultimate purpose of medical innovation is to improve the lives of people affected by disease.

This balance is particularly important in MG, where symptoms can fluctuate considerably and where the impact of disease varies from one individual to another. Two patients with similar clinical assessments may describe very different experiences in their daily lives.

Understanding those lived experiences helps us better appreciate what patients value, what challenges remain unmet and how treatment goals may continue to evolve over time.

At the American Association of Neuromuscular and Electrodiagnostic Medicine (AANEM) annual meeting / MGFA Scientific Session this week, UCB research being presented - including 23 abstracts and 2 oral presentations - is contributing to the growing evidence base evaluating MSE as a meaningful, patient-centered treatment outcome in generalized MG. The research adds to our understanding of how frequently MSE can be achieved and how it may inform evolving treatment goals in clinical practice.

By considering both scientific evidence and patient perspectives, we can gain deeper insight into what meaningful improvement truly looks like for people living with MG.

Looking ahead

Looking ahead, I believe our ambition should extend beyond managing symptoms and controlling disease activity.

As our understanding of MG advances, so too should our expectations of what treatment can achieve. For many people living with MG, meaningful success is not simply measured by clinical improvement, but by the ability to participate more fully in daily life with fewer limitations and less uncertainty.

MSE reflects that aspiration. It represents a state associated with minimal symptom burden and limited interference from MG in everyday activities, allowing people to focus more on the people, relationships and opportunities that matter most to them.

Whenever I meet people living with MG, I am reminded that their aspirations are rarely about scores or measurements. They talk about family, work, travel, friendships and the simple freedom to make plans with confidence.

If MSE helps us move closer to that reality for more people, then it represents much more than a clinical outcome. It represents meaningful progress.

That is what continues to motivate me, and what motivates all of us at UCB.
 

Frequently Asked Questions 

What is myasthenia gravis (MG)?
Myasthenia gravis is an autoimmune disease that causes muscle weakness and fatigue. Symptoms can affect activities such as speaking, swallowing, breathing and mobility.

What is minimal symptom expression (MSE)?
Minimal symptom expression is a treatment goal in myasthenia gravis, defined as an MG-ADL score of 0 or 1, that reflects minimal or no interference from MG symptoms.

Why is MSE important for people living with MG?
MSE provides patient perspective beyond clinical assessment and focuses on how people experience their condition.

What is the MG-ADL scale?
The Myasthenia Gravis Activities of Daily Living (MG-ADL) scale is a patient-reported measure used to assess how MG symptoms affect every day functioning e.g. talking, chewing, swallowing.