Rystiggo

Approved Uses

Rystiggo is specifically indicated for the treatment of generalized myasthenia gravis (gMG) in adults. It is used for patients who have tested positive for one of the following antibodies:

• Anti-acetylcholine receptor (AChR) antibodies: These are the most common antibodies found in people with gMG.
• Anti-muscle-specific tyrosine kinase (MuSK) antibodies: This is a less common type of antibody found in some gMG patients.

Generalized myasthenia gravis is a chronic autoimmune condition that leads to muscle weakness. This weakness often affects the muscles responsible for eye movement, facial expressions, swallowing, and breathing, as well as the muscles in the arms and legs.

Healthcare providers use Rystiggo to help manage the symptoms of this condition in patients who meet these specific antibody criteria. It is not intended for use in patients who do not have these specific antibodies.

Mechanism of Action

Rystiggo belongs to a class of medications known as neonatal Fc receptor (FcRn) blockers. It is used to treat generalized myasthenia gravis (gMG), an autoimmune condition where the body produces harmful proteins called autoantibodies. These autoantibodies attack the areas where nerves and muscles communicate, leading to muscle weakness and fatigue.

In the body, a specific protein called the neonatal Fc receptor (FcRn) normally helps recycle antibodies, preventing them from being broken down and keeping them in the bloodstream longer. Rystiggo works by binding to these FcRn receptors and blocking them.

When these receptors are blocked, the body can no longer recycle the antibodies. This leads to several effects:

• Increased breakdown: The harmful autoantibodies are broken down and removed by the body more quickly.
• Lower antibody levels: There is a significant reduction in the overall levels of Immunoglobulin G (IgG) antibodies, which include the specific autoantibodies that cause gMG symptoms.
• Reduced muscle attack: With fewer autoantibodies circulating in the blood, the immune system's attack on the nerve-muscle connection is weakened.

By lowering the concentration of these harmful antibodies, Rystiggo helps improve physical strength and the ability to perform daily activities in people with gMG.

Common Side Effects

The most frequently reported side effects of Rystiggo include:

• Headache
• Diarrhea
• Nausea
• Fever
• Injection site reactions, such as pain, redness, or swelling
• Abdominal pain
• Joint pain (arthralgia)

Serious Side Effects

While less common, Rystiggo can cause serious health issues. Seek medical attention immediately if you experience symptoms of the following:

• Infections: Because Rystiggo affects the immune system, it may increase the risk of infections, including upper respiratory tract infections and urinary tract infections.
• Aseptic Meningitis: This is a non-infectious inflammation of the lining of the brain. Symptoms include severe headache, neck stiffness, fever, nausea, vomiting, and sensitivity to light.
• Hypersensitivity Reactions: Some patients may experience allergic reactions. Symptoms can include rash, itching, swelling, or difficulty breathing.

Infections

Rystiggo may increase the risk of infections because it lowers the levels of immunoglobulin G (IgG) in the body. Treatment should not be started in individuals with a clinically significant active infection. If an infection develops during treatment, monitoring is required, and the medication may be paused until the infection is resolved.

Aseptic Meningitis

Cases of aseptic meningitis, which is inflammation of the lining of the brain and spinal cord not caused by bacteria, have occurred with this medication. Symptoms typically appear within two to three days of a dose and may include:

• Severe headache
• Fever
• Nausea and vomiting
• Stiff neck
• Sensitivity to light

Hypersensitivity Reactions

Serious allergic reactions, including rash and swelling under the skin (angioedema), have been reported. If a hypersensitivity reaction occurs, the administration should be stopped immediately and medical treatment provided. Rystiggo is contraindicated in patients with a history of severe hypersensitivity to rozanolixizumab-noli or its ingredients.

Vaccinations

The safety of live-attenuated or live vaccines has not been studied in people taking Rystiggo. It is recommended to complete all necessary vaccinations before starting treatment. Live vaccines should be avoided during therapy.

Pregnancy

There is limited information regarding the safety of Rystiggo during pregnancy. It is not yet known if the medication can cause harm to an unborn baby or lead to pregnancy loss. Because Rystiggo is a monoclonal antibody, it is likely to cross the placenta and reach the developing fetus.

In animal studies, no adverse effects on fetal development were observed at doses higher than those typically used in humans. If you are pregnant or planning to become pregnant, you should discuss the potential risks and benefits with your healthcare provider before starting or continuing treatment.

Breastfeeding

It is unknown if Rystiggo passes into breast milk or if it has any effect on a nursing infant or milk production. While many antibodies are present in human milk, the specific impact of Rystiggo is not established. Consult your doctor to determine the best course of action if you are breastfeeding or planning to breastfeed while using this medication.

Dosage Forms

Rystiggo is supplied in the following form:

• Subcutaneous Injection: A sterile, preservative-free solution provided in a single-dose vial.

The medication is a clear to opalescent liquid that may range from colorless to pale brownish-yellow. It is administered as an infusion under the skin, typically using an infusion pump.

FDA Approval History

The U.S. Food and Drug Administration (FDA) approved Rystiggo on June 27, 2023. During its development, the medication received several regulatory designations, including Orphan Drug and Priority Review status, which are intended to fast-track treatments for rare and serious conditions.

Approved Indications

Rystiggo is indicated for the treatment of generalized myasthenia gravis (gMG) in adult patients. Its use is specifically limited to patients who test positive for certain antibodies, including:

• Anti-acetylcholine receptor (AChR) antibodies
• Anti-muscle-specific tyrosine kinase (MuSK) antibodies

Regulatory Requirements and Safety Monitoring

There are currently no boxed warnings or Risk Evaluation and Mitigation Strategies (REMS) required by the FDA for Rystiggo. However, the regulatory approval includes specific safety warnings that healthcare providers must monitor:

• Infections: Because the drug reduces immunoglobulin G (IgG) levels, it may increase the risk of developing infections.
• Aseptic Meningitis: Cases of non-infectious brain lining inflammation have been reported in clinical trials.
• Hypersensitivity Reactions: Serious allergic reactions, such as angioedema and rash, may occur during or after administration.

The FDA approval was based on clinical data showing that the medication significantly improved activities of daily living scores for patients with gMG compared to those receiving a placebo.

Factors Affecting Cost

The actual price you pay for Rystiggo depends on several variables. Because it is a specialty medication administered by a healthcare professional, costs are not limited to the drug itself. Factors include:

• Insurance Plan: Your specific coverage, including deductibles, copays, and coinsurance, will determine your out-of-pocket responsibility. Many insurance plans require prior authorization for this treatment.
• Administration Fees: Rystiggo is given as a subcutaneous infusion by a healthcare provider. You may be billed for the office visit, the professional services required to administer the drug, and any facility fees.
• Specialty Pharmacy: This medication is typically distributed through specialty pharmacies rather than standard retail pharmacies, which can affect the billing process.

Financial Assistance and Support

There are programs available to help manage the costs associated with Rystiggo treatment:

• Manufacturer Support: The pharmaceutical company that produces Rystiggo often provides patient support services to help navigate insurance coverage and identify financial assistance options.
• Copay Assistance: Patients with commercial or private insurance may be eligible for copay cards or savings programs that reduce out-of-pocket expenses.
• Patient Assistance Programs: For individuals who are uninsured or underinsured, programs may exist to provide the medication at a reduced cost or for free, depending on financial eligibility.

To understand your specific costs, it is best to contact your insurance provider and the manufacturer's support program for a detailed breakdown of your coverage and potential assistance.