FDA-filed SPL labeling · retrieved through openFDA

Reslizumab Injection

Reslizumab is a biologic injection used as add-on maintenance treatment for severe asthma in adults who have high levels of a specific immune cell called eosinophils.

Brand name Cinqair
Drug class Interleukin-5 Antagonist
Rx Form 1 Route Intravenous
Dr. Brian Staiger, PharmD, BCPS
Reviewed by Last reviewed Jul 10, 2026
🧬 Where this information comes from Click to expand

The clinical label records used on this page are FDA-filed Structured Product Labeling (SPL) retrieved through openFDA. We identified 1 clinical label set within the page’s selected clinical scope after exact ingredient or ingredient-combination matching and applicable route/form matching. Forms, routes, brands, labelers, strengths, and NDC product-record counts are built separately from matching FDA National Drug Code Directory records. The linked DailyMed document is a representative official source for verification, not the page’s only clinical source. View the linked label on DailyMed →

At a glance
Linked label effectiveFeb 29, 2020
AvailabilityRx
Earliest approval/marketing year 2016
FDA-listed product records 2
Boxed warningYes
How we combine label and product data →
No current FDA shortage listed · checked Sep 15, 2026
Reslizumab Injection at a glance The quick version — the full detail is in the Patient Information Guide below.
💊
HelloPharmacist Editorial Team Bottom Line
Cinqair (reslizumab) is a monthly IV infusion for adults with severe eosinophilic asthma that isn't controlled on standard inhalers alone — it works by reducing the eosinophil levels that drive airway inflammation. It is always given in a clinical setting because of the risk of a serious allergic reaction, so you'll be monitored after every dose. It is a maintenance treatment only and will not help during an acute asthma attack.
⚠️ FDA Boxed Warning — the FDA’s strongest safety alert

Cinqair carries a Boxed Warning — the FDA's most serious safety alert — for anaphylaxis, a severe and potentially life-threatening allergic reaction. This reaction occurred in about 0.3% of patients in clinical trials and happened as early as the second infusion. Signs include difficulty breathing, wheezing, drop in oxygen levels, vomiting, hives, or other skin and mouth reactions. Because of this risk, Cinqair must only be given by a healthcare professional who is prepared to treat anaphylaxis. You will be monitored during and after each infusion. If you experience any of these symptoms, the infusion must be stopped immediately and you should receive emergency care. Cinqair should be permanently discontinued if anaphylaxis occurs.

Read the full warning on DailyMed →

📖 Reslizumab Injection: Patient Information Guide

A plain-language walkthrough of Reslizumab Injection — what it treats, how it works, how it’s taken, side effects, warnings and interactions. Tap any section to expand it.

🎯What it's used for

Reslizumab injection (brand: Cinqair) is approved for one specific use in adults:

  • Cinqair is indicated as add-on maintenance treatment for adults aged 18 and older with severe asthma driven by elevated eosinophil levels (eosinophilic phenotype) — used alongside, not instead of, other asthma therapies
  • Cinqair is not approved for the relief of sudden asthma attacks (acute bronchospasm) or status asthmaticus (a prolonged, dangerous asthma attack)
  • Cinqair is not approved to treat other medical conditions caused by high eosinophil levels
  • Cinqair is not approved for anyone under 18 years of age
⚙️How it works

Reslizumab works by blocking a protein called interleukin-5 (IL-5) — the key signal that tells the body to produce, activate, and keep alive a type of immune cell called an eosinophil. In some people with severe asthma, too many eosinophils build up in the airways and drive chronic inflammation, making asthma harder to control. By binding tightly to IL-5 and preventing it from attaching to eosinophil receptors, reslizumab sharply reduces the number of eosinophils in the blood — in clinical studies, levels dropped by about 92% over 52 weeks compared to 21% with placebo. This reduction in eosinophils is thought to help reduce airway inflammation, though the exact mechanism in asthma has not been fully established.

💊How it's taken

Cinqair is given as a weight-based intravenous (IV) infusion administered by a healthcare professional — it cannot be self-administered at home. It is given once every 4 weeks, and each infusion takes 20 to 50 minutes depending on your body weight. Food intake does not apply since this medicine is given directly into a vein.

  • Always given in a clinical setting — never at home
  • Administered once monthly (every 4 weeks)
  • You will be monitored during and after the infusion for signs of a serious allergic reaction
  • If you miss a scheduled infusion, contact your healthcare provider to reschedule as soon as possible
🤒Side effects — in detail

Most people tolerate Cinqair well, but some side effects have been reported:

  • Throat or mouth pain (oropharyngeal pain) — the most common side effect, occurring in about 2.6% of patients
  • Muscle aches (myalgia) — reported in about 1% of Cinqair patients
  • Musculoskeletal pain on infusion day — including chest, neck, extremity pain, or muscle spasms
  • Elevated CPK (creatine phosphokinase) on blood tests — a marker of muscle activity; elevations were usually asymptomatic and did not require stopping treatment

More seriously, anaphylaxis (a life-threatening allergic reaction) occurred in 0.3% of patients and can happen during or shortly after the infusion — seek emergency help immediately if you have trouble breathing, hives, vomiting, or feel faint. A slightly higher rate of malignancies was also observed in Cinqair-treated patients compared to placebo.

⚠️Warnings & precautions
  • Anaphylaxis (severe allergic reaction): The most critical risk. Can occur during or within 20 minutes after the infusion, even as early as the second dose. Signs include difficulty breathing, wheezing, hives, vomiting, and low oxygen levels. Cinqair must be stopped immediately and discontinued permanently if this happens.
  • Not for acute attacks: Cinqair is a maintenance medicine only. Never use it to treat a sudden asthma flare or emergency — seek appropriate acute care instead.
  • Malignancy: Cancers were reported slightly more often in Cinqair patients (0.6%) than placebo (0.3%) in clinical studies. Report any unexplained symptoms or new growths to your doctor.
  • Corticosteroid tapering: Never stop your corticosteroid medicines suddenly when starting Cinqair. Any reduction must be gradual and supervised by a physician, as stopping abruptly can cause withdrawal or unmask hidden conditions.
  • Parasitic infections: Eosinophils help fight certain worm infections. Cinqair reduces eosinophils, so existing helminth infections should be treated before starting. If a new infection develops and doesn't respond to treatment, Cinqair may need to be paused.
🔀What it interacts with

No formal clinical drug interaction studies have been performed with Cinqair. Based on available data:

  • Leukotriene antagonists (e.g., montelukast) — commonly used in asthma; do not appear to affect how the body processes reslizumab
  • Corticosteroids — frequently taken alongside Cinqair; do not appear to change reslizumab levels in the body, but should never be stopped suddenly when beginning Cinqair
  • Other IV medications: Cinqair must not be infused through the same IV line as any other drug — no compatibility studies have been done

This is not a complete list of interactions. Always talk with your doctor or pharmacist before starting, stopping, or changing any medication.

📋Before taking it
  • Known allergy to reslizumab or any Cinqair ingredient: Do not take Cinqair — this is a contraindication
  • Pregnancy: Data are limited. Reslizumab can cross the placenta, especially in the second and third trimesters. Poorly controlled asthma itself carries risks during pregnancy. Discuss the balance of benefits and risks with your doctor.
  • Breastfeeding: It is not known whether reslizumab passes into human breast milk. Discuss with your doctor before breastfeeding while on Cinqair.
  • Children and teenagers (under 18): Cinqair is not approved for this age group. In adolescents studied, asthma exacerbation rates were actually higher with Cinqair than placebo.
  • Adults 65 and older: No dose adjustment is needed based on available data; safety and effectiveness were similar to younger adults.
  • Parasitic (helminth) infections: Tell your doctor if you have or have had a worm infection — it should be fully treated before starting Cinqair.
  • Liver or kidney disease: Population analyses suggest reslizumab levels are not significantly affected by mild liver impairment or mild-to-moderate kidney impairment, but tell your doctor about any organ health concerns.
🚑If you take too much

In clinical studies, single doses considerably higher than the recommended amount were given to patients without clear dose-related toxic effects. There is no specific antidote for a Cinqair overdose. If an overdose is suspected, supportive medical care and monitoring would be provided by healthcare professionals.

📡Pharmacodynamics — effects in the body

After the first Cinqair infusion, blood eosinophil counts begin to fall quickly — measurable reductions are seen within 2 to 3 days. Over 52 weeks of treatment, blood eosinophil levels dropped by about 92% in Cinqair patients compared to 21% in those on placebo. These reductions were sustained throughout treatment with no sign of the body adapting or becoming tolerant. When Cinqair is stopped, eosinophil levels gradually return toward pre-treatment levels over approximately 120 days after the last dose.

🔬Pharmacokinetics — how your body processes it

Reslizumab reaches its peak blood concentration at the end of each infusion, then gradually clears from the body over the following weeks. It has a half-life of about 24 days, meaning it takes roughly 24 days for the body to clear half of the drug — which is why once-monthly dosing is sufficient. The drug stays mostly in the bloodstream with minimal spread into surrounding tissues. Like other monoclonal antibodies, it is broken down by normal protein-digesting enzymes in the body rather than by liver enzymes, so standard drug metabolism pathways (such as CYP enzymes) are not involved.

📦How to store it

Refrigerate at 2 ºC to 8ºC (36°F to 46°F). Do not freeze. storing in the original package until time of use.

📄 Written from Reslizumab Injection’s FDA-approved label information, summarized in plain language with AI, and reviewed by our pharmacy team before publication. Every point is grounded in that labeling — nothing is invented. How we use AI →

🩺 Pharmacist Counseling Corner

Quick, plain-English answers to the questions patients ask most about Reslizumab Injection — the kind of thing our pharmacy team would talk through with you at the counter.

What exactly is Cinqair for, and why did my doctor prescribe it if I already use inhalers?
Cinqair is an add-on treatment for adults with severe asthma who have high levels of a specific immune cell called eosinophils. If your asthma isn't fully controlled on inhalers alone, your doctor may have found that eosinophil-driven inflammation is part of the problem. Cinqair works differently from inhalers — it targets the immune signal that creates too many of those cells in the first place. It's not a replacement for your other medications; it works alongside them.
Can I use Cinqair if I have an asthma attack?
No — Cinqair is a maintenance medicine, which means it's meant to prevent attacks over time, not treat one in the moment. If you're having an acute asthma attack or trouble breathing right now, use your rescue inhaler and seek emergency medical care. Cinqair won't help during a flare and is not designed for that purpose.
What's the serious allergic reaction risk I keep hearing about?
This is the most important safety concern with Cinqair. A severe allergic reaction called anaphylaxis happened in about 0.3% of patients in studies — that's roughly 3 in 1,000 people. It can happen during the infusion or within about 20 minutes afterward, and it can be life-threatening. That's exactly why Cinqair is only given in a clinical setting where staff are trained and ready to treat it immediately. Signs to watch for include trouble breathing, wheezing, skin hives, vomiting, or feeling faint. If any of those happen, you'd be treated right away and Cinqair would be permanently stopped.
Do I need to stop my other asthma medications when I start Cinqair?
No — and this is really important — do not stop your corticosteroids suddenly. Your doctor may eventually consider reducing your steroid dose if things are going well, but any change must happen slowly and under medical supervision. Stopping steroids abruptly can cause serious withdrawal effects or uncover other health problems that were being suppressed. Keep taking all your other asthma medications as prescribed unless your doctor tells you otherwise.
Is Cinqair safe during pregnancy?
There isn't enough human data yet to know for certain. What we do know is that reslizumab can cross the placenta — especially in the second and third trimesters — and the drug stays in the body for a long time (about a 24-day half-life). That said, poorly controlled asthma during pregnancy also carries real risks for you and your baby. This is a conversation worth having honestly with your OB and prescribing doctor so you can weigh what's best for both of you.
What should I watch out for between infusions?
Most side effects with Cinqair are mild — things like a sore throat or some muscle aches, especially on infusion day. But call your doctor if your asthma symptoms are getting worse instead of better, if you notice any unusual lumps or growths, or if you think you might have a parasitic infection (like an intestinal worm) that isn't clearing up with treatment. And always go to the emergency room if you ever have breathing trouble, hives, or feel like you might pass out — even days after an infusion.
Is Reslizumab Injection available over the counter?
Reslizumab Injection is dispensed by prescription according to its FDA labeling, so it isn't sold over the counter. Your prescriber and pharmacist will determine if it's appropriate for you.
When was Reslizumab Injection first available?
Reslizumab Injection has been available in the United States since at least 2016, based on FDA approval history (Drugs@FDA) and product marketing records.

💬 Answers drafted from Reslizumab Injection’s FDA-approved label information, summarized in plain language with AI, and reviewed by our pharmacy team before publication. Grounded in that labeling — nothing is made up. How we use AI →

🧰 Keep exploring

💊 How Reslizumab Injection comes

Reslizumab Injection is available in 1 form. Different forms and brands can have different approved uses, doses, schedules, and directions. Follow the instructions for your exact product, and do not switch forms without guidance from your prescriber or pharmacist.

Injection

Into a vein
Brands Cinqair
How this form is used
What it may be used for
  • Cinqair is used as add-on maintenance treatment for severe asthma with an eosinophilic phenotype in adults 18 years and older
  • Cinqair is not for relief of acute asthma attacks or sudden bronchospasm
  • Cinqair is not approved for other conditions involving high eosinophil levels
Important instructions
  • Cinqair is given by intravenous infusion only — never as an IV push or bolus injection
  • Cinqair is administered once every 4 weeks over a 20 to 50 minute infusion period by a healthcare professional
  • Cinqair must be given in a setting where anaphylaxis can be immediately treated; patients are observed during and after the infusion
  • Cinqair must not be mixed or infused in the same IV line with any other medications
Available strengths 1 strength
2 FDA-listed product records

📊 Reslizumab Injection across the U.S. market

How Reslizumab Injection appears in the FDA’s National Drug Code Directory — including its dosage forms, strengths, brand names, manufacturers, and FDA-listed product records. These are directory records, not sales or prescription volume.

1
Dose forms
1
Manufacturers
1
Brand names
2
FDA-listed product records
2016
First marketed

🔍 Compare Reslizumab Injection products

A representative set of FDA-listed product records for Reslizumab Injection — across manufacturers, strengths, and dosage forms, grouped by form with each product’s manufacturer and how the FDA approved it. The same medicine may be made and packaged by different companies, so a single drug can have many directory entries. (It’s also why a refill can look different — a new shape, color, or box — even though it contains the same medication.)

Strength Route Manufacturer / Labeler Category Details
💊Injection
10 mg/mL Intravenous Teva Respiratory, LLC × 2 listings BLA View NDC →

Showing 2 of 2 products — FDA National Drug Code Directory. See every product, package size and price: browse all 2 Reslizumab Injection NDCs →

RxNorm Concept Web — From Ingredient to Every Form and Strength

This page starts with one ingredient concept (IN). The branches below show its dose-form concepts (SCDF), then the available clinical drug and strength concepts (SCD). Combination products remain separate concepts with their own pages.

Ingredient (IN) Reslizumab Injection RxCUI 1746889 1 dose form · 1 strength
  1. Dose form (SCDF) Injection RxCUI 1746892 In current FDA listings
    Clinical drug / strength (SCD) 10 ML reslizumab 10 MG/ML RxCUI 1746893

Look up RxCUI 1746889 in the RxCUI Atlas →

RxNorm is the U.S. National Library of Medicine’s normalized drug vocabulary. Its concept hierarchy can include forms that are not currently marketed; the status on each branch compares that concept with current FDA listings. RxCUIs identify vocabulary concepts, not individual packages or manufacturers.

🏷️ Sold under these brand names

Cinqair

🏭 Manufacturers & labelers

Teva Respiratory, LLC 2

RxNorm drug class

Reslizumab Injection belongs to the Interleukin-5 Antagonist class.

Pharmacologic class Interleukin-5 Antagonist
Drug family (ATC) Other systemic drugs for obstructive airway diseases
How it works Interleukin-5 Antagonists

Classified by RxNorm RxClass — the U.S. National Library of Medicine's standardized drug-classification service (Established Pharmacologic Class from the FDA, the ATC drug family from the WHO, and mechanism of action). Reference only, not medical advice.

🔬 Where this comes from

Core label, product, RxNorm, safety, and utilization data on this page come from the sources identified below. AI-written, editorial, and licensed sections are labeled separately.

📄
FDA-filed drug labels (SPL) Uses, dosing, warnings & side effects from SPL records retrieved through openFDA; the linked representative set can be verified on DailyMed. ✓ Linked label effective Feb 29, 2020
🏭
Forms, brands & labelersAggregated from ingredient-matched FDA National Drug Code Directory product records for Reslizumab Injection.
📈
Real-world reportsThe FDA Adverse Event Reporting System (FAERS), served through openFDA.
🚨
Recalls & shortagesopenFDA drug-enforcement reports and the FDA drug-shortage database.
🧾 Clinical label set — FDA-filed SPL labels retained for Reslizumab Injection after exact ingredient or ingredient-combination matching and applicable route/form matching
Clinical labels in scope
1
NDC products indexed
2
Distinct labelers/manufacturers represented
1
Linked representative label
Teva Respiratory, LLC
Linked label effective
Feb 29, 2020
Composite sections available
22
Linked SPL Set ID
053b9158-2a5b-48b9-bf47-5fa78a35ec33
Linked SPL Document ID
a509df2c-67b6-40c3-8b6d-f9de54b62c8a
Open the linked representative label on DailyMed ↗

How we combine label and product data

HelloPharmacist combines public FDA and NLM records; we don’t author the underlying clinical facts. We identified 1 FDA-filed SPL label set within the page’s selected clinical scope after exact ingredient or ingredient-combination matching and applicable route/form matching. The representative label is the starting point for the displayed reference monograph; the 12 largest stored in-scope SPL records, which may include that representative, are compared section by section, and the longest available version of each section is retained. Forms, routes, brands, labelers, product-listed strengths, and product-record counts are aggregated separately from ingredient-matched FDA NDC Directory records; package records listed above are associated with the linked SPL; and the normalized concept hierarchy comes from NLM RxNorm.

Where a section is identified as AI-written, its plain-language text is generated from bounded label evidence. New draft drug pages remain in the admin review queue before first publication. Teva Respiratory, LLC is the representative DailyMed label linked for verification and dates; it is not the sole source used for the page.

This is general education, not medical advice — always consult your doctor or pharmacist about your medications and any medical condition. For the exact wording of the linked representative label, view that label on DailyMed; some displayed composite sections may come from other in-scope SPL labels. Learn how we use AI and our data sources & update cadence.