Fasenra

Primary Use

Fasenra is indicated for the long-term treatment of severe asthma in adults and children 6 years of age and older. It is specifically used for patients who have an eosinophilic phenotype. Eosinophils are a type of white blood cell that, when present in high levels, can cause inflammation in the airways, making it difficult to breathe.

Add-on Maintenance Treatment

This medication is used as an add-on treatment, meaning it is prescribed alongside other daily asthma maintenance medicines. It is intended for patients whose asthma is not well-controlled by their current medications, such as high-dose corticosteroid inhalers. The goal of treatment is to:

• Reduce the frequency of severe asthma attacks (exacerbations).
• Improve overall lung function.
• Help reduce the need for oral corticosteroids in some patients.

Important Limitations

Fasenra has specific limitations regarding its use in emergency situations:

• Not a rescue medication: Fasenra is not used to treat sudden breathing problems or an acute asthma attack. It will not work fast enough to relieve a sudden onset of symptoms.
• Not for status asthmaticus: It is not indicated for the treatment of status asthmaticus, which is a severe, life-threatening asthma attack that does not respond to standard treatments.

Targeting Eosinophils

Fasenra belongs to a class of medications known as monoclonal antibodies. It is specifically designed to target eosinophils, which are a type of white blood cell. While these cells are a normal part of the immune system, having too many of them can cause the airways to become inflamed and swollen, making it difficult to breathe.

How It Works in the Body

The medication works by identifying and helping the body remove excess eosinophils through the following steps:

• Binding: Fasenra attaches to a specific protein called the interleukin-5 (IL-5) receptor alpha, which is located on the surface of eosinophils.
• Immune Activation: By binding to this receptor, the drug attracts natural killer cells, a type of immune cell that destroys targeted cells.
• Depletion: This process leads to a rapid and near-total reduction of eosinophils in the blood and the lungs.

By reducing the number of these inflammatory cells, Fasenra helps to decrease airway swelling and mucus production. This helps prevent severe asthma attacks and improves overall lung function over time. It does not work immediately and is not intended to replace a rescue inhaler for sudden symptoms.

Common Side Effects

Some people using Fasenra may experience mild side effects. These typically include:

• Headache
• Sore throat (pharyngitis)
• Fever
• Injection site reactions, including redness, itching, swelling, or pain where the shot was given

Serious Side Effects

Fasenra can cause serious allergic reactions, including anaphylaxis. These reactions can occur within hours of the injection or may be delayed and appear several days later. Seek emergency medical help immediately if you experience:

• Swelling of the face, lips, or tongue
• Difficulty breathing or wheezing
• Hives or a widespread skin rash
• Dizziness, lightheadedness, or fainting

Hypersensitivity Reactions

Serious allergic reactions, such as anaphylaxis, angioedema, and hives, have occurred in patients receiving Fasenra. These reactions may happen within hours of the injection or may be delayed, appearing several days later. If a serious hypersensitivity reaction occurs, treatment is typically discontinued.

Acute Asthma Symptoms

Fasenra should not be used to treat acute asthma symptoms, acute bronchospasm, or status asthmaticus. It is a maintenance treatment and does not replace rescue inhalers for sudden breathing problems.

Reduction of Corticosteroids

Patients should not suddenly stop or reduce their systemic or inhaled corticosteroid medications upon starting Fasenra. Any reduction in corticosteroid dosage should be performed gradually and under medical supervision, as withdrawal symptoms or a return of asthma symptoms may occur.

Parasitic Infections

Because eosinophils are involved in the immune response to some helminth (parasitic) infections, Fasenra may influence the body's ability to fight these infections. Pre-existing parasitic infections should be treated before starting Fasenra. If a patient becomes infected while using the medication and does not respond to anti-parasitic treatment, Fasenra may be discontinued until the infection is resolved.

Pregnancy

There are no adequate and well-controlled studies of Fasenra in pregnant women. While animal studies in monkeys did not show evidence of harm to the fetus, human data are insufficient to confirm safety. Monoclonal antibodies like Fasenra are known to cross the placenta, particularly during the second and third trimesters, which could potentially affect the fetus.

It is important to manage asthma effectively during pregnancy, as poorly controlled asthma can increase the risk of complications for both the mother and the baby, such as preeclampsia and low birth weight. Patients are encouraged to discuss their treatment plan with their doctor if they are pregnant or planning to become pregnant.

Breastfeeding

It is currently unknown if Fasenra is excreted in human breast milk. Although many antibodies are present in milk, the effects on a nursing infant are not well understood. The decision to breastfeed while using Fasenra should involve a discussion with a healthcare provider to consider the health benefits of breastfeeding alongside the mother's clinical need for the medication.

Available Forms

Fasenra is supplied as a sterile, preservative-free liquid solution for injection. It is available in the following formats:

• Single-dose prefilled syringe: A syringe containing the medication for injection under the skin.
• Single-dose autoinjector: A device, also known as the Fasenra Pen, designed for subcutaneous administration.

The medication is a clear to opalescent, colorless to slightly yellow liquid intended for subcutaneous use only.

FDA Approval History

The U.S. Food and Drug Administration (FDA) first approved Fasenra in November 2017. It was initially authorized as an add-on maintenance treatment for patients aged 12 years and older with severe asthma who have an eosinophilic phenotype. In April 2024, the FDA expanded this approval to include children aged 6 to 11 years with the same condition.

In September 2024, the FDA granted further approval for Fasenra to treat adults with eosinophilic granulomatosis with polyangiitis (EGPA), a rare autoimmune condition characterized by inflammation of small and medium-sized blood vessels.

Regulatory Status and Safety

Fasenra is classified as a biologic drug and is available only by prescription. It is not intended for the treatment of other eosinophilic conditions or for the relief of acute breathing emergencies, such as acute bronchospasm or status asthmaticus.

There are currently no boxed warnings or Risk Evaluation and Mitigation Strategies (REMS) required for this medication. However, the FDA has monitored and updated labeling regarding potential serious risks, including:

• Hypersensitivity Reactions: Serious allergic reactions, including anaphylaxis, have been reported. These reactions can occur within hours of administration or may have a delayed onset of several days.
• Helminth Infection: Because eosinophils are involved in the body's response to parasite infections, patients with pre-existing helminth infections should be treated for the infection before starting Fasenra.

The FDA continues to monitor the safety profile of Fasenra through the FDA Adverse Event Reporting System (FAERS). In 2019, the FDA identified a potential signal of serious risk for hypersensitivity, which resulted in updated safety information in the drug's labeling.

Insurance and Coverage

Fasenra is a biologic medication, and its cost is primarily determined by your insurance provider. Coverage can vary significantly between private insurance, Medicare, and Medicaid. Your out-of-pocket expenses will depend on your plan's specific deductibles and co-pay structures.

Administration and Pharmacy Factors

Several logistical factors can influence the final price of the medication:

• Administration Site: Costs may vary depending on whether the injection is given by a healthcare professional in a clinical setting or self-administered at home.
• Specialty Pharmacy: Because it is a complex biologic, Fasenra is typically dispensed through specialty pharmacies rather than standard retail locations.

Financial Assistance Programs

Support options are often available to help patients manage the cost of treatment:

• Co-pay Savings: Patients with commercial insurance may be eligible for programs that lower their monthly out-of-pocket costs.
• Patient Assistance: For those without insurance or with limited financial means, manufacturer programs may provide the medication at a reduced cost or for free.