Omalizumab

Asthma

Omalizumab is used to treat moderate to severe persistent asthma in adults and children 6 years of age and older. It is specifically for patients whose asthma is triggered by year-round allergens and whose symptoms are not well-controlled by inhaled corticosteroid medications.

Chronic Hives

This medication is used to treat chronic spontaneous urticaria (hives with no known cause) in adults and children 12 years of age and older. It is typically prescribed when antihistamine treatments have failed to manage the condition.

Nasal Polyps

In adults, omalizumab is used as an add-on maintenance treatment for nasal polyps. It is used when nasal corticosteroids have not been effective in managing the polyps.

Food Allergies

Omalizumab is used in adults and children 1 year of age and older to help reduce the risk of allergic reactions, including anaphylaxis, that may occur after accidental exposure to one or more foods. It is intended for people with certain types of food allergies.

Important Limitations

• It is not used for the emergency treatment of an asthma attack.
• It is not used for the immediate treatment of an acute allergic reaction, including anaphylaxis.
• People taking this for food allergies must still continue to avoid the foods they are allergic to.

Mechanism of Action

Omalizumab is a laboratory-made monoclonal antibody designed to target and bind to immunoglobulin E (IgE). IgE is a type of antibody produced by the immune system that plays a key role in allergic responses.

In people with allergic asthma, chronic hives, or food allergies, the immune system produces IgE in response to triggers like pollen, pet dander, or specific proteins in food. Omalizumab works through the following steps:

• Binding to IgE: The medication circulates in the blood and attaches to free IgE molecules before they can cause a reaction.
• Blocking Immune Cell Activation: By binding to IgE, omalizumab prevents the IgE from attaching to receptors on the surface of specific immune cells, such as mast cells and basophils.
• Reducing Chemical Release: Because the IgE cannot attach to these immune cells, the cells do not release histamine and other inflammatory chemicals that lead to symptoms like wheezing, swelling, and itching.

By lowering the levels of free IgE in the body, omalizumab helps dampen the immune system's overreaction to allergens. This process helps reduce the frequency of asthma attacks and limits the severity of allergic reactions caused by accidental exposure to trigger foods.

Common Side Effects

Many people using omalizumab experience mild side effects. These often include:

• Pain, redness, swelling, or itching at the injection site
• Headache
• Tiredness or fatigue
• Joint or muscle pain
• Dizziness
• Sore throat or cold-like symptoms
• Nausea or stomach discomfort

Serious Side Effects

While less common, some side effects can be severe and require immediate medical attention:

• Severe Allergic Reactions: This can happen right after an injection or several days later. Symptoms include hives, swelling of the face or throat, difficulty breathing, and feeling faint.
• Heart and Circulation Problems: Some reports suggest a possible increased risk of heart attack, stroke, or chest pain.
• Inflammation of Blood Vessels: Symptoms may include a rash, pins and needles sensation, or numbness in the arms or legs.
• Parasitic Infections: This medication may make it easier to get certain types of worm infections in people who are already at high risk for them.
• Fever and Joint Stiffness: A group of symptoms including fever, rash, and joint pain may occur one to five days after treatment.

Severe Allergic Reactions

Omalizumab has a boxed warning because it can cause anaphylaxis, a sudden and life-threatening allergic reaction. This can happen even if no reaction occurred with previous doses. Symptoms may include wheezing, shortness of breath, fainting, or swelling of the tongue and throat. Because these reactions can be delayed, patients are typically monitored by a healthcare provider for a period after the injection.

Limitations of Use

This medication is not a rescue treatment. It should not be used to treat sudden breathing problems, such as an acute asthma attack or bronchospasm. For individuals with food allergies, omalizumab is used to reduce the risk of reactions from accidental exposure; it is not for the emergency treatment of an allergic reaction and does not allow for the intentional consumption of known food allergens.

Heart and Circulation Concerns

There is a potential increased risk of serious side effects involving the heart and blood vessels. These may include blood clots in the lungs or veins, heart attack, stroke, or sudden chest pain.

Additional Safety Considerations

• Malignancy: A slight increase in the risk of certain types of cancer has been observed in some clinical studies.
• Parasitic Infections: The medication may lower the body's resistance to certain types of parasite infections, such as roundworms or hookworms.
• Steroid Medication: If taking oral or inhaled corticosteroids, these should not be stopped or reduced abruptly when starting omalizumab. Any reduction in dosage must be done gradually under medical supervision.
• Eosinophilic Conditions: Rarely, patients may experience a serious condition involving blood vessel inflammation or high levels of eosinophils, a type of white blood cell.

Pregnancy

There is limited information regarding the safety of omalizumab use during pregnancy. While animal studies have not shown evidence of harm to the fetus, there are no adequate and well-controlled studies in humans. Because untreated asthma or other allergic conditions can pose risks to both the mother and the baby, healthcare providers must weigh the benefits of treatment against any potential risks.

If you are pregnant or planning to become pregnant, discuss your treatment plan with your doctor. If you become pregnant while using omalizumab, notify your healthcare provider immediately. You may be encouraged to enroll in a pregnancy registry, which monitors the health of mothers and babies to collect more information about the effects of the medication during pregnancy.

Breastfeeding

It is not fully known if omalizumab passes into human breast milk or how it might affect a nursing infant. Some clinical evidence suggests that the risk to the infant may be minimal, but because many medications are excreted in breast milk, caution is advised. You should consult your doctor to determine if the benefits of breastfeeding outweigh the potential risks to the infant while you are receiving this medication.

Available Forms

Omalizumab is administered as an injection under the skin (subcutaneously). It is available in the following delivery systems:

• Prefilled Syringe: A syringe containing the medication in liquid form, used for manual injection.
• Autoinjector: A device containing the medication in liquid form, designed to automate the injection process for patients or caregivers.
• Vial: A container of lyophilized (freeze-dried) powder that must be reconstituted into a liquid by a healthcare professional before administration.

FDA Approval and Indications

Omalizumab is approved by the U.S. Food and Drug Administration (FDA) for several specific conditions involving the immune system:

• Asthma: For adults and children 6 years of age and older with moderate to severe persistent asthma whose symptoms are not well controlled by inhaled corticosteroids and who have a positive skin or blood test for year-round allergens.
• Chronic Spontaneous Urticaria (CSU): For adults and adolescents 12 years of age and older with chronic hives that do not have a known cause and continue despite treatment with H1 antihistamines.
• Nasal Polyps: For adults 18 years of age and older as an add-on maintenance treatment when nasal corticosteroids have not worked well enough.
• Food Allergies: For adults and children 1 year of age and older to help reduce the risk of allergic reactions, including anaphylaxis, that may occur after accidental exposure to one or more foods. It is not intended for the emergency treatment of allergic reactions.

Boxed Warning

The FDA has issued a boxed warning for omalizumab because it can cause anaphylaxis, a sudden and life-threatening allergic reaction. This reaction can happen after the first dose or after many doses, and it may occur immediately or several hours after the injection. Because of this risk, healthcare providers must monitor patients closely after administration, and patients are often prescribed an epinephrine auto-injector for emergency use.

Regulatory History and Safety

Omalizumab was first approved in 2003. In 2014, the FDA added information to the label regarding a potential increased risk of serious cardiovascular and cerebrovascular events, such as heart disease or stroke, based on a safety review. It remains a prescription-only biologic medication administered by subcutaneous injection.

Factors Affecting Cost

The total expense for omalizumab treatment is influenced by several factors related to the prescription and administration process:

• Administration Setting: Omalizumab is typically administered by a healthcare professional in a medical office or clinic, which may involve additional costs for the visit and the injection procedure. Some patients may be eligible to self-inject at home after receiving training, which can change the associated costs.
• Dosage and Frequency: The dose is often determined by the patient's body weight and specific lab results, such as immunoglobulin E (IgE) levels. Patients requiring higher doses or more frequent injections (every 2 to 4 weeks) will face higher overall costs.
• Insurance Coverage: Most insurance plans cover omalizumab, but the patient's out-of-pocket responsibility, such as copays or coinsurance, depends on the specific terms of their policy.

Financial Assistance

Patients may be able to access financial support to help manage the costs of this medication:

• Copay Cards: The manufacturer may offer copay cards for patients with commercial insurance to help lower out-of-pocket expenses.
• Patient Assistance Programs: There are programs available for patients who are uninsured or underinsured to help them obtain the medication at a reduced cost or for free, provided they meet certain eligibility requirements.