T-cell fighting cancer cell representing immunotherapy, with a faded figure struggling to breathe.

Nivolumab and Myasthenia Gravis: What You Need to Know About This Cancer Treatment's Unexpected Side Effect

Beau Callahan in Health & Wellness November 2025 • 4 min read.

"A comprehensive look at nivolumab-induced myasthenia gravis, its symptoms, and what patients and caregivers should watch out for."

Nivolumab is an immunotherapy drug that has revolutionized the treatment of several aggressive cancers. By blocking the programmed cell death-1 (PD-1) receptor, it unleashes the immune system to fight cancer cells. While this approach has shown remarkable success, it also carries the risk of triggering immune-related adverse effects, one of which is myasthenia gravis (MG).

Myasthenia gravis is a chronic autoimmune neuromuscular disease that causes weakness in the skeletal muscles, which are responsible for breathing and moving parts of the body. It occurs when the body's immune system mistakenly attacks the connections between nerves and muscles. Symptoms can vary widely, but often include drooping eyelids, double vision, difficulty swallowing, and fatigue. In severe cases, MG can lead to respiratory failure.

This article will explore a case of nivolumab-induced myasthenia gravis, shedding light on the importance of recognizing this potential side effect. We'll delve into the symptoms, diagnosis, and management of MG in the context of cancer immunotherapy, providing valuable information for patients, caregivers, and healthcare professionals.

Understanding Nivolumab and Its Mechanism of Action

T-cell fighting cancer cell representing immunotherapy, with a faded figure struggling to breathe.

Nivolumab is a type of immunotherapy called a checkpoint inhibitor. These drugs work by blocking certain proteins, called checkpoints, that prevent T cells (a type of immune cell) from attacking cancer cells. PD-1 is one such checkpoint found on T cells. By blocking PD-1, nivolumab allows T cells to recognize and kill cancer cells more effectively.

While nivolumab is effective against cancers like melanoma, non-small cell lung cancer, and renal cell carcinoma, its mechanism of action can also lead to unintended consequences. By revving up the immune system, nivolumab can sometimes cause it to attack healthy tissues, leading to autoimmune diseases. Myasthenia gravis is one such potential autoimmune side effect.

Here's a breakdown of the process:

Nivolumab binds to the PD-1 receptor on T cells.
This blocks the interaction between PD-1 and its ligands (PD-L1 and PD-L2), which are often found on cancer cells.
By blocking this interaction, nivolumab prevents the cancer cell from deactivating the T cell.
The T cell remains active and is able to attack and kill the cancer cell.

The case study presented in the original article highlights this risk. A 73-year-old male with metastatic renal cell carcinoma developed myasthenia gravis after starting nivolumab treatment. He presented with fatigue and weakness, eventually progressing to respiratory failure. This case underscores the importance of vigilance and prompt recognition of MG symptoms in patients receiving nivolumab.

The Importance of Early Detection and Management

Nivolumab is a valuable tool in the fight against cancer, but it's crucial to be aware of its potential side effects. If you or a loved one is undergoing nivolumab treatment, be vigilant for symptoms of myasthenia gravis, such as muscle weakness, drooping eyelids, double vision, and difficulty swallowing or breathing. Early detection and prompt treatment can significantly improve outcomes and prevent severe complications.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.7759/cureus.1702, Alternate LINK

Title: Myasthenia Gravis Induced By Nivolumab: A Case Report

Subject: Aerospace Engineering

Journal: Cureus

Publisher: Cureus, Inc.

Authors: Jeet J Mehta, Eamon Maloney, Sachin Srinivasan, Patrick Seitz, Michael Cannon

Published: 2017-09-20

Everything You Need To Know

How does Nivolumab work to fight cancer, and what is the role of the PD-1 receptor in this process?

Nivolumab is an immunotherapy medication known as a checkpoint inhibitor. It functions by obstructing the programmed cell death-1 (PD-1) receptor found on T cells. This blockade prevents the PD-1 receptor from interacting with its ligands, PD-L1 and PD-L2, which are frequently present on cancer cells. By disrupting this interaction, Nivolumab prevents the cancer cells from deactivating T cells, enabling the T cells to remain active and target and eliminate cancer cells more effectively.

What is Myasthenia gravis (MG), and what are the common symptoms that patients and caregivers should be aware of?

Myasthenia gravis (MG) is a chronic autoimmune neuromuscular condition marked by skeletal muscle weakness. This weakness arises when the immune system mistakenly attacks the connections between nerves and muscles. Key symptoms include drooping eyelids, double vision, difficulty swallowing, and fatigue. In severe instances, Myasthenia gravis can lead to respiratory failure, highlighting the importance of early detection and management.

What is the connection between Nivolumab treatment and the development of Myasthenia gravis (MG), and why does this side effect occur?

While Nivolumab is an effective cancer treatment, it can induce immune-related adverse effects, including Myasthenia gravis (MG). Nivolumab's mechanism, which involves enhancing the immune system, can lead to the immune system attacking healthy tissues, resulting in autoimmune conditions like Myasthenia gravis. Therefore, vigilance for symptoms such as muscle weakness, drooping eyelids, and double vision is essential for those undergoing Nivolumab treatment.

Why is early detection and management of Myasthenia gravis (MG) so important for patients undergoing Nivolumab treatment?

Early detection of Myasthenia gravis (MG) symptoms is critical for improving outcomes in patients undergoing Nivolumab treatment. Symptoms such as muscle weakness, drooping eyelids, double vision, and difficulty swallowing or breathing should be promptly reported. Early diagnosis and management can prevent severe complications like respiratory failure and significantly enhance the patient's quality of life. The 73-year-old male with metastatic renal cell carcinoma developed Myasthenia gravis after starting Nivolumab treatment as described, highlights the importance of vigilance.

What are the potential implications of Nivolumab's mechanism of action, specifically regarding the balance between anti-cancer immunity and autoimmune reactions?

Nivolumab's mechanism of action, which involves blocking the PD-1 receptor on T cells to enhance the immune system's ability to fight cancer cells, can have unintended consequences. While this blockade prevents cancer cells from deactivating T cells, it can also lead to the immune system attacking healthy tissues, resulting in autoimmune diseases like Myasthenia gravis (MG). This underscores the delicate balance between enhancing anti-cancer immunity and the risk of triggering autoimmune reactions, necessitating careful monitoring and management of patients receiving Nivolumab.