Ultomiris: Un tratamiento para la miastenia grave generalizada

If you are diagnosed with generalized miastenia gravis (gMG), your healthcare provider might prescribe Ultomiris. 

What Is Ultomiris?

Ultomiris is an FDA-approved medication indicated for the treatment of generalized myasthenia gravis (gMG) in adult patients who are anti-acetylcholine receptor (Anti-AChR) antibody positive. 

Positive test results for anti-acetylcholine receptor (Anti-AChR) antibodies indicate the presence of these autoantibodies, which contribute to the development of myasthenia gravis. 

Ultomiris is also known by the name of the component (or active substance) it contains, called ravulizumab, and is only available to patients who are registered in the Ultomiris REMS (Risk Evaluation and Mitigation Strategy) program. 

What Happens in Generalized Myasthenia Gravis?

Normally, when a healthy person wants to move or lift something, their brain sends signals to muscles through nerves. These nerves release acetylcholine (a chemical), which attaches to its receptor on the skeletal muscle cell and causes muscle contraction. 

However, in people with gMG, their immune system produces autoantibodies, commonly anti-acetylcholine receptor (Anti-AChR) antibodies that target and block the acetylcholine receptor (AChR) and prevent the muscle from contracting. 

The binding of anti-AChR (autoantibody) to its target triggers the activation of the complement system, consisting of the group of immune proteins that are normally present in the blood in an inactive state. 

When the complement system is activated, it attacks and damages the healthy muscle cells and interrupts the nerve signal transmission, which results in gMG symptoms such as muscle weakness and fatigue.

The binding of anti-AChR (autoantibody) to its target triggers the activation of the complement system, consisting of the group of immune proteins that are normally present in the blood in an inactive state. 
When the complement system is activated, it attacks and damages the healthy muscle cells and interrupts the nerve signal transmission, which results in gMG symptoms such as muscle weakness and fatigue.

How Does Ultomiris Work?

Ultomiris contains an active component, “ravulizumab,” which is a monoclonal antibody specifically designed to bind and inhibit the activation of the complement system. 

Ultomiris Mode of Action

Ravulizumab, which is the active substance of Ultomiris, blocks a key protein (C5-protein) within the complement system. This key protein activates other complement proteins and damages the muscle cells in gMG. By inhibiting the C5 protein, Ultomiris blocks the activation of the complement system and prevents muscle damage in gMG. 
 

How Is Ultomiris Administered to Myasthenia Gravis Patients?

Ultomiris comes in a single-dose vial that is administered intravenously via IV infusion, starting with a loading dose. Following the loading dose, the first maintenance dose is administered 2 weeks later, and the subsequent doses are administered every 8 weeks. 
 

What Are the Recommended Doses of Ultomiris for Myasthenia Gravis Patients?

The dosage of Ultomiris is adjusted according to the patient’s body weight (Kg) and disease condition. Based on the FDA dosage guideline, the usual doses of Ultomiris for adults with gMG are as follows:
For patients weighing 40 kg to less than 60 kg:
The loading dose is 2,400 mg, followed by the maintenance dose of 3,000 mg every 8 weeks. 
For patients weighing 60 kg to less than 100 kg:
The loading dose is 2,700 mg, followed by the maintenance dose of 3,300 mg every 8 weeks. 
For patients weighing 100 kg or greater:
The loading dose is 3,000 mg, followed by the maintenance dose of 3,600 mg every 8 weeks.
 

What Are the Possible Side Effects of Ultomiris in gMG Patients?

The most common side effects of Ultomiris reported by adult patients with generalized myasthenia are diarrhea and upper respiratory tract infection. 

Ultomiris also carries a box warning for serious meningococcal infections and sepsis, which can be life-threatening if not diagnosed and treated earlier. Therefore, it is recommended that patients receive a vaccine to protect against meningococcal infections at least 2 weeks before they start an Ultomiris infusion treatment. 

Who Should Not Take Ultomiris?

Anyone with an ongoing Neisseria meningitidis infection—the bacteria that causes meningococcal disease—should not use Ultomiris.

In addition, patients who have not received a Neisseria meningitidis vaccination should not receive the therapy unless postponing treatment would result in a greater risk of meningococcal infection.

What Precautions Should You Follow Before Taking Ultomiris Infusions?

Consult your healthcare provider in the following cases before starting the Ultomiris infusions: 

• Si tienes una fever or infection, you should not receive Ultomiris because it can worsen your condition.
• Si tu estas pregnant o intend to become pregnant, you should not receive Ultomiris, since the effect of this drug on unborn babies is still unknown. 
• Si tu estas amamantando o planea amamantar, you should not receive Ultomiris.  Since it is not known if Ultomiris passes into your breastmilk, it is therefore recommended to NOT breastfeed during the treatment and after the treatment for at least 8 months.
• If you are allergic to any Ultomiris component, you should not receive Ultomiris infusions. 
• If you take multivitamins, herbal supplements, or over-the-counter medicines, consult your healthcare provider for dose adjustments. 

Conclusión

In summary, Ultomiris (ravulizumab) is an intravenous prescription for treating the symptoms of generalized myasthenia gravis. This drug inhibits the key protein-C5 within the complement system — a part of the immune system that disturbs the nerve signal transmission and causes gMG.