Nucala (Mepolizumab)

Brand Name

Nucala

Generic Name

Mepolizumab

View Brand Information

FDA approval date: November 04, 2015

Classification: Interleukin-5 Antagonist

Form: Injection

What is Nucala (Mepolizumab)?

Breathing shouldn’t feel like a constant battle. For many people with severe asthma, nasal polyps or rare eosinophilic disorders, standard treatments may not fully control symptoms. Nucala (generic name: mepolizumab) offers a modern, targeted option designed to reduce inflammation in the airways driven by a specific type of immune cell. By focusing on this pathway, Nucala can help decrease asthma attacks, improve lung function and enhance quality of life for patients with stubborn disease.

Nucala is a monoclonal antibody in the class of interleukin-5 (IL-5) inhibitors. Although it is not a first-line therapy, it’s used as add-on (additional) treatment when inhalers and other standard medicines aren’t sufficient. Because it addresses a specific inflammatory pathway, many patients find it more tolerable and effective than broad immune suppressants.

What does Nucala do?

Nucala is approved for several conditions related to eosinophilic inflammation, which is a process involving high levels of eosinophils (a type of white blood cell). It is used as add-on therapy for:

Severe eosinophilic asthma in children aged 6 and older and in adults (to reduce exacerbations and improve control)
Chronic rhinosinusitis with nasal polyps (CRSwNP) in adults whose disease is not fully controlled by nasal steroids
Eosinophilic granulomatosis with polyangiitis (EGPA), an inflammatory disease affecting blood vessels in adults
Hypereosinophilic syndrome (HES) in patients 12 years or older with persistent high eosinophil levels
Eosinophilic chronic obstructive pulmonary disease (COPD) in adults whose disease has an eosinophilic component and is not well controlled

In clinical trials, patients using Nucala experienced reductions in the number of asthma exacerbations, fewer hospitalizations and improvements in symptom scores versus placebo. By helping lower blood eosinophil counts, Nucala reduces the inflammatory damage these cells cause in lung tissue, nasal passages and elsewhere.

How does Nucala work?

Nucala works by neutralizing interleukin-5 (IL-5), a key signaling molecule that supports eosinophil growth, activation and survival. As a monoclonal antibody, mepolizumab binds to IL-5 in the bloodstream so it can’t interact with its receptor on eosinophil cells.

With less IL-5 activity, eosinophils decrease in number, which leads to lower inflammation and reduced damage in tissues like the lungs and sinuses. Clinically, suppressing IL-5 is valuable because it targets one root cause of asthma attacks and nasal polyp growth rather than broadly dampening the immune system.

Because Nucala acts specifically on eosinophils, it tends to have fewer side effects involving general immune suppression compared to older treatments like systemic steroids.

Nucala side effects

Like all medications, Nucala carries potential side effects. Most are mild, but some may require attention.

Common side effects (occurring in ≥5% of treated patients) include:

Headache
Injection site reactions: redness, swelling, pain, or itching
Back pain
Fatigue (tiredness)

Less common/serious side effects:

Hypersensitivity reactions including anaphylaxis, angioedema, bronchospasm or rash
Herpes zoster (shingles) infections have been observed; vaccination may be considered in eligible patients
Use caution if the patient has parasitic (helminth) infection

Avoid Nucala if hypersensitive to mepolizumab or any ingredient. Do not use for acute asthma attacks or sudden breathing issues. Treat parasitic infections before starting. Safety not established for children under 6 (asthma) or younger ages for other conditions.

If you experience swelling of the face, mouth, tongue, difficulty breathing or a severe rash, seek emergency medical attention immediately.

Nucala dosage

Nucala is administered as a subcutaneous injection (an injection given just under the skin). The standard dosing schedule for most conditions is once every four weeks.

Nucala offers flexible administration options. It can be given by a healthcare professional in a clinic setting. Alternatively, it is available in a pre-filled autoinjector pen or a pre-filled syringe, which allows patients or their caregivers to administer the injection at home after receiving proper training from a healthcare provider. This can offer significant convenience and reduce the need for frequent clinic visits.

Routine lab tests are generally not needed solely for Nucala use in stable patients. Clinicians monitor clinical response (exacerbation frequency, symptom scores, lung function) and adverse effects. Closer follow-up is required for certain diseases (e.g., EGPA, HES) to manage immunologic and organ effects. Patients should continue other asthma medications unless directed otherwise; do not stop abruptly. After training and stability, patients can self-administer Nucala at home.

Does Nucala have a generic version?

No. Nucala is a biologic drug, and as of now no generic or biosimilar version is approved for use in the U.S. However, international versions may exist in other markets.

Because biologic medications are complex proteins produced in living systems, generic equivalents (called “biosimilars”) must undergo rigorous testing to assure safety and similarity. Until then, Nucala remains a brand-only therapy.

Patients concerned about cost may ask their clinicians or pharmacies about assistance programs, insurance coverage, or patient support resources offered by the manufacturer.

Conclusion

Nucala (mepolizumab) is a sophisticated, targeted therapy that has expanded the treatment options for patients with eosinophilic-driven diseases, especially severe asthma. By blocking IL-5 and reducing eosinophil-mediated inflammation, it helps prevent asthma attacks, ease symptoms, and improve respiratory function in patients whose disease remains uncontrolled by standard therapies.

While side effects and risks exist particularly hypersensitivity reactions and infections, most patients tolerate Nucala well. Its monthly dosing and availability in autoinjector form make it relatively convenient for long-term use under medical supervision.

Nucala is most effective when used as part of a comprehensive care plan. Patients should maintain regular follow-ups, adhere to all prescribed inhalers or therapies, and communicate promptly with their care team about any side effects or changes in symptoms.

Used appropriately, Nucala offers many patients safer, more stable breathing and a better quality of life.

References

U.S. Food and Drug Administration. Nucala (mepolizumab) Prescribing Information, revised 2023. FDA Access Data+1
Drugs.com. Nucala (mepolizumab) Information. Drugs.com
DrugBank. Mepolizumab Mechanism and Pharmacology. DrugBank
EMA / European Medicines Agency. Nucala Information. European Medicines Agency (EMA)

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Brand Information

Nucala (mepolizumab)

1DOSAGE FORMS AND STRENGTHS

For Injection

100 mg white to off-white lyophilized powder in a single-dose vial for reconstitution.

Injection

100 mg/mL as a clear to opalescent, colorless to pale yellow to pale brown solution in a single-dose prefilled autoinjector.
100 mg/mL as a clear to opalescent, colorless to pale yellow to pale brown solution in a single-dose prefilled glass syringe.
40 mg/0.4 mL as a clear to opalescent, colorless to pale yellow to pale brown solution in a single-dose prefilled glass syringe.

2CONTRAINDICATIONS

NUCALA is contraindicated in patients with a history of hypersensitivity to mepolizumab or excipients in the formulation

3ADVERSE REACTIONS

The following adverse reactions are described in greater detail in other sections:

Hypersensitivity reactions
Opportunistic infections: herpes zoster

3.1Clinical Trials Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared with rates in the clinical trials of another drug and may not reflect the rates observed in practice.

Adverse Reactions in Adult and Adolescent Patients Aged 12 Years and Older with Severe Asthma

A total of 1,327 patients with severe asthma were evaluated in 3 randomized, placebo-controlled, multicenter trials of 24 to 52 weeks’ duration (Severe Asthma Trials DREAM, MENSA, and SIRIUS). Of these, 1,192 had a history of 2 or more exacerbations in the year prior to enrollment despite regular use of high-dose ICS plus additional controller(s) (Severe Asthma Trials DREAM and MENSA), and 135 patients required daily oral corticosteroids (OCS) in addition to regular use of high-dose ICS plus additional controller(s) to maintain asthma control (Severe Asthma Trial SIRIUS). All patients had markers of eosinophilic airway inflammation

The incidence of adverse reactions in the first 24 weeks of treatment in the 2 confirmatory efficacy and safety trials MENSA and SIRIUS with NUCALA 100 mg is shown in

52-Week Trial: Adverse reactions from the Severe Asthma Trial DREAM with 52 weeks of treatment with mepolizumab 75 mg intravenously (n = 153) or placebo (n = 155) and with ≥3% incidence and more common than placebo and not shown in Table 2 were: abdominal pain, allergic rhinitis, asthenia, bronchitis, cystitis, dizziness, dyspnea, ear infection, gastroenteritis, lower respiratory tract infection, musculoskeletal pain, nasal congestion, nasopharyngitis, nausea, pharyngitis, pyrexia, rash, toothache, viral infection, viral respiratory tract infection, and vomiting. In addition, 3 cases of herpes zoster occurred in patients receiving mepolizumab 75 mg intravenously compared with 2 patients in the placebo group.

Systemic Reactions, including Hypersensitivity Reactions: In the Severe Asthma Trials DREAM, MENSA, and SIRIUS described above, the percentage of patients who experienced systemic (allergic and non-allergic) reactions was 3% in the group receiving NUCALA 100 mg and 5% in the placebo group. Systemic allergic/hypersensitivity reactions were reported by 1% of patients in the group receiving NUCALA 100 mg and 2% of patients in the placebo group. The most commonly reported manifestations of systemic allergic/hypersensitivity reactions reported in the group receiving NUCALA 100 mg included rash, pruritus, headache, and myalgia. Systemic non-allergic reactions were reported by 2% of patients in the group receiving NUCALA 100 mg and 3% of patients in the placebo group. The most commonly reported manifestations of systemic non‑allergic reactions reported in the group receiving NUCALA 100 mg included rash, flushing, and myalgia. A majority of the systemic reactions in patients receiving NUCALA 100 mg (5/7) were experienced on the day of dosing.

Injection Site Reactions: Injection site reactions (e.g., pain, erythema, swelling, itching, burning sensation) occurred at a rate of 8% in patients receiving NUCALA 100 mg compared with 3% in patients receiving placebo.

Long-Term Safety: Nine hundred ninety-eight patients received NUCALA 100 mg in open-label extension studies, during which additional cases of herpes zoster were reported. The overall adverse event profile has been similar to the severe asthma trials described above.

Adverse Reactions in Pediatric Patients Aged 6 to 11 Years with Severe Asthma

The safety data for NUCALA is based upon 1 open-label clinical trial that enrolled 36 patients with severe asthma aged 6 to 11 years. Patients received 40 mg (for those weighing <40 kg) or 100 mg (for those weighing ≥40 kg) of NUCALA administered subcutaneously once every 4 weeks. Patients received NUCALA for 12 weeks (initial short phase). After a treatment interruption of 8 weeks, 30 patients received NUCALA for a further 52 weeks (long phase). The adverse reaction profile for patients aged 6 to 11 years was similar to that observed in patients aged 12 years and older.

Adverse Reactions in Adult Patients with Chronic Rhinosinusitis with Nasal Polyps

A total of 407 patients with CRSwNP were evaluated in 1 randomized, placebo-controlled, multicenter, 52-week treatment trial. Patients received NUCALA 100 mg or placebo subcutaneously once every 4 weeks. Patients had recurrent CRSwNP with a history of prior surgery and were on nasal corticosteroids for at least 8 weeks prior to screening

Table 3 summarizes adverse reactions that occurred in ≥3% of patients treated with NUCALA and more frequently than in patients treated with placebo in the CRSwNP trial.

Systemic Reactions, including Hypersensitivity Reactions: In the 52-week trial, the percentage of patients who experienced systemic (allergic [type I hypersensitivity] and other) reactions was <1% in the group receiving NUCALA 100 mg and <1% in the placebo group. Systemic allergic (type I hypersensitivity) reactions were reported by <1% of patients in the group receiving NUCALA 100 mg and no patients in the placebo group. The manifestations of systemic allergic (type I hypersensitivity) reactions included urticaria, erythema, and rash and 1 of the 3 reactions occurred on the day of dosing. Other systemic reactions were reported by no patients in the group receiving NUCALA 100 mg and <1% of patients in the placebo group.

Injection Site Reactions: Injection site reactions (e.g., erythema, pruritus) occurred at a rate of 2% in patients receiving NUCALA 100 mg compared with <1% in patients receiving placebo.

Adverse Reactions in Adults with Chronic Obstructive Pulmonary Disease

The safety data below reflects the safety of NUCALA in adults with inadequately controlled COPD and an eosinophilic phenotype. NUCALA was evaluated in a pooled safety population that consisted of 2089 patients with COPD in 3 randomized, placebo-controlled, multicenter trials of 52 to 104 weeks duration, including MATINEE and METREX

Table 4 summarizes adverse reactions that occurred in ≥3% of patients treated with NUCALA and more frequently than in patients treated with placebo in COPD trials.

Herpes Zoster: In the pooled safety population, 14 (1%) patients in the NUCALA group compared to 7 (0.7%) patients in the placebo group experienced herpes zoster.

Adverse Reactions in Patients with Eosinophilic Granulomatosis with Polyangiitis

A total of 136 patients with EGPA were evaluated in 1 randomized, placebo-controlled, multicenter, 52-week treatment trial. Patients received 300 mg of NUCALA or placebo subcutaneously once every 4 weeks. Patients enrolled had a diagnosis of EGPA for at least 6 months prior to enrollment with a history of relapsing or refractory disease and were on a stable dosage of oral prednisolone or prednisone of greater than or equal to 7.5 mg/day (but not greater than 50 mg/day) for at least 4 weeks prior to enrollment

Systemic Reactions, including Hypersensitivity Reactions: In the 52-week trial, the percentage of patients who experienced systemic (allergic and non‑allergic) reactions was 6% in the group receiving 300 mg of NUCALA and 1% in the placebo group. Systemic allergic/hypersensitivity reactions were reported by 4% of patients in the group receiving 300 mg of NUCALA and 1% of patients in the placebo group. The manifestations of systemic allergic/hypersensitivity reactions reported in the group receiving 300 mg of NUCALA included rash, pruritus, flushing, fatigue, hypertension, warm sensation in trunk and neck, cold extremities, dyspnea, and stridor. Systemic non-allergic reactions were reported by 1 (1%) patient in the group receiving 300 mg of NUCALA and no patients in the placebo group. The reported manifestation of systemic non-allergic reactions reported in the group receiving 300 mg of NUCALA was angioedema. Half of the systemic reactions in patients receiving 300 mg of NUCALA (2/4) were experienced on the day of dosing.

Injection Site Reactions: Injection site reactions (e.g., pain, erythema, swelling) occurred at a rate of 15% in patients receiving 300 mg of NUCALA compared with 13% in patients receiving placebo.

Adverse Reactions in Adult and Adolescent Patients with Hypereosinophilic Syndrome

A total of 108 adult and adolescent patients aged 12 years and older with HES were evaluated in a randomized, placebo‑controlled, multicenter, 32-week treatment trial. Patients with non-hematologic secondary HES or FIP1L1‑PDGFRα kinase-positive HES were excluded from the trial. Patients received 300 mg of NUCALA or placebo subcutaneously once every 4 weeks. Patients must have been on a stable dose of background HES therapy for the 4 weeks prior to randomization

Systemic Reactions, including Hypersensitivity Reactions: In the trial, no systemic allergic (type I hypersensitivity) reactions were reported. Other systemic reactions were reported by 1 (2%) patient in the group receiving 300 mg of NUCALA and no patients in the placebo group. The reported manifestation of other systemic reaction was multifocal skin reaction experienced on the day of dosing.

Injection Site Reactions: Injection site reactions (e.g., burning, itching) occurred at a rate of 7% in patients receiving 300 mg of NUCALA compared with 4% in patients receiving placebo.

3.2Postmarketing Experience

In addition to adverse reactions reported from clinical trials, the following adverse reactions have been identified during post-approval use of NUCALA. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. These events have been chosen for inclusion due to either their seriousness, frequency of reporting, or causal connection to NUCALA or a combination of these factors.

Immune System Disorders

Hypersensitivity reactions, including anaphylaxis.

4DRUG INTERACTIONS

Formal drug interaction trials have not been performed with NUCALA.

5OVERDOSAGE

There is no specific treatment for an overdose with mepolizumab. If overdose occurs, the patient should be treated supportively with appropriate monitoring as necessary. Consider contacting the Poison Help line (1-800-222-1222) or a medical toxicologist for additional overdose management recommendations.

6DESCRIPTION

Mepolizumab is a humanized IL-5 antagonist monoclonal antibody. Mepolizumab is produced by recombinant DNA technology in Chinese hamster ovary cells. Mepolizumab has a molecular weight of approximately 149 kDa.

NUCALA for injection is a sterile, preservative-free, white to off-white, lyophilized powder in a single-dose vial for subcutaneous injection after reconstitution. Upon reconstitution with 1.2 mL of Sterile Water for Injection, USP, the resulting concentration is 100 mg/mL and delivers 1 mL

The vial stopper is not made with natural rubber latex.

NUCALA injection is a sterile, preservative-free, clear to opalescent, colorless to pale yellow to pale brown solution for subcutaneous use.

NUCALA injection is supplied in a single-dose, 1-mL, prefilled autoinjector with a fixed 29‑gauge, half-inch needle and in a single-dose, 1-mL, prefilled syringe with a fixed 29‑gauge, half-inch needle with a needle guard. Each 1 mL delivers 100 mg mepolizumab, citric acid monohydrate (0.95 mg), EDTA disodium dihydrate (0.019 mg), polysorbate 80 (0.20 mg), sodium phosphate dibasic heptahydrate (4.16 mg), and sucrose (120 mg), with a pH of 6.3.

NUCALA injection is supplied in a single-dose, 0.4-mL, prefilled syringe with a fixed 29-gauge, half-inch needle with a needle guard. Each 0.4 mL delivers 40 mg mepolizumab, citric acid monohydrate (0.38 mg), EDTA disodium dihydrate (0.0074 mg), polysorbate 80 (0.08 mg), sodium phosphate dibasic heptahydrate (1.66 mg), and sucrose (48 mg), with a pH of 6.3.

The prefilled autoinjector and prefilled syringe are not made with natural rubber latex.

7HOW SUPPLIED/STORAGE AND HANDLING

NUCALA for Injection

NUCALA (mepolizumab) for injection is a sterile, preservative-free, white to off-white, lyophilized powder for reconstitution and subcutaneous injection in a single-dose glass vial with a flip-off seal. The vial stopper is not made with natural rubber latex.

NUCALA for injection is supplied as:

100-mg single-dose vials in cartons of 1 (NDC 0173-0881-01).

Store vials below 77°F (25°C). Do not freeze. Store in the original carton to protect from light.

NUCALA Injection

NUCALA (mepolizumab) injection is a sterile, preservative-free, clear to opalescent, colorless to pale yellow to pale brown solution for subcutaneous use. Each single-dose prefilled autoinjector delivers 100 mg of mepolizumab in 1 mL of solution. Each single-dose prefilled syringe delivers 100 mg of mepolizumab in 1 mL of solution or 40 mg of mepolizumab in 0.4 mL of solution. The autoinjectors and syringes are not made with natural rubber latex.

NUCALA injection is supplied as:

100 mg/mL, single-dose, prefilled autoinjector with attached 29-gauge, half-inch needle in cartons of 1 (NDC 0173-0892-01).
100 mg/mL, single-dose, prefilled glass syringe with attached 29-gauge, half-inch needle with a needle guard in cartons of 1 (NDC 0173-0892-42).
40 mg/0.4 mL, single-dose, prefilled glass syringe with attached 29-gauge, half-inch needle with a needle guard in cartons of 1 (NDC 0173-0904-42).

Prior to Dispensing: Refrigerate prefilled autoinjectors and prefilled syringes at 36°F to 46°F (2°C to 8°C). Keep the product in the original carton to protect from light. Do not freeze. Do not shake. Avoid exposure to heat.

Following Dispensing: Refrigerate prefilled autoinjectors and prefilled syringes at 36°F to 46°F (2°C to 8°C). Keep the product in the original carton to protect from light until the time of use. Do not freeze. Do not shake. Avoid exposure to heat.

If necessary, an unopened carton can be stored outside the refrigerator at up to 86°F (30°C) for up to 7 days. Discard if left out of the refrigerator for more than 7 days.

NUCALA injection must be administered within 8 hours after removal from the carton. Discard if not administered within 8 hours.

8PATIENT COUNSELING INFORMATION

Advise the patient to read the FDA-approved patient labeling (Patient Information and Instructions for Use).

Hypersensitivity Reactions

Inform patients that hypersensitivity reactions (e.g., anaphylaxis, angioedema, bronchospasm, hypotension, urticaria, rash) have occurred after administration of NUCALA. Instruct patients to contact their healthcare provider if such reactions occur.

Not for Acute Symptoms or Deteriorating Disease

Inform patients that NUCALA does not treat acute asthma symptoms or acute exacerbations of asthma or COPD. Inform patients to seek medical advice if their asthma remains uncontrolled or COPD symptoms worsen after initiation of treatment with NUCALA.

Opportunistic Infections: Herpes Zoster

Inform patients that herpes zoster infections have occurred in patients receiving NUCALA and where medically appropriate, inform patients that vaccination should be considered.

Reduction of Corticosteroid Dosage

Inform patients to not discontinue systemic or inhaled corticosteroids except under the direct supervision of a physician. Inform patients that reduction in corticosteroid dose may be associated with systemic withdrawal symptoms and/or unmask conditions previously suppressed by systemic corticosteroid therapy.

Trademarks are owned by or licensed to the GSK group of companies.

Manufactured by

Distributed by

GlaxoSmithKline

NCL:13PI