Last reviewed 2026-04-20 · How we verify

Cinqair (RESLIZUMAB)

Cinqair works by blocking the action of interleukin-5, a protein that promotes the production of eosinophils, which contribute to inflammation in the airways.

Cinqair (reslizumab) is a small molecule interleukin-5 antagonist developed by TEVA RESPIRATORY LLC. It targets interleukin-5, a protein involved in the production of eosinophils, which contribute to inflammation in the airways. Cinqair is FDA-approved for the treatment of eosinophilic asthma. The drug has a long half-life of 24 days, allowing for less frequent dosing. Cinqair remains a patented product, with its commercial status unchanged.

At a glance

Mechanism of action

Reslizumab is an interleukin-5 antagonist (IgG4, kappa). IL-5 is the major cytokine responsible for the growth and differentiation, recruitment, activation, and survival of eosinophils. Reslizumab binds to IL-5 with dissociation constant of 81 pM, inhibiting the bioactivity of IL-5 by blocking its binding to the alpha chain of the IL-5 receptor complex expressed on the eosinophil surface. Inflammation is an important component in the pathogenesis of asthma. Multiple cell types (e.g., mast cells, eosinophils, neutrophils, macrophages, lymphocytes) and mediators (e.g., histamine, eicosanoids, leukotrienes, cytokines) are involved in inflammation. Reslizumab, by inhibiting IL-5 signaling, reduces the production and survival of eosinophils; however, the mechanism of reslizumab action in asthma has not been definitively established.

Approved indications

• Eosinophilic asthma

Boxed warnings

• WARNING: ANAPHYLAXIS Anaphylaxis has been observed with CINQAIR infusion in 0.3% of patients in placebo-controlled clinical studies. Anaphylaxis was reported as early as the second dose of CINQAIR [see Warnings and Precautions ( 5.1 ), Adverse Reactions ( 6 )] . Anaphylaxis can be life-threatening. Patients should be observed for an appropriate period of time after CINQAIR administration by a healthcare professional prepared to manage anaphylaxis. Discontinue CINQAIR immediately if the patient experiences signs or symptoms of anaphylaxis [see Dosage and Administration ( 2.2 ), Warnings and Precautions ( 5.1 )] . WARNING: ANAPHYLAXIS See full prescribing information for complete boxed warning. Anaphylaxis occurred with CINQAIR infusion in 0.3% of patients in placebo-controlled studies ( 5.1 ) Patients should be observed for an appropriate period of time after CINQAIR infusion; healthcare professionals should be prepared to manage anaphylaxis that can be life-threatening ( 5.1 ) Discontinue CINQAIR immediately if the patient experiences anaphylaxis ( 5.1 )

Common side effects

• Oropharyngeal pain
• CPK elevations
• Muscle-related adverse reactions
• Myalgia
• Musculoskeletal adverse reactions
• Anaphylaxis
• Malignancy
• Elevated baseline creatine phosphokinase (CPK)
• Muscle spasms
• Extremity pain
• Muscle fatigue
• Musculoskeletal pain

Key clinical trials

• Dupilumab as Add-On Therapy for Hypereosinophilic Syndrome With Partial Clinical Response to Eosinophil-Depleting Biologic Agents (PHASE2)
• A Retrospective Chart Review to Investigate Clinical Remission in Patients With Severe Asthma Treated With Biologics in the United Kingdom National Health Service
• Pharmacodynamic Biomarkers to Support Biosimilar Development: Interleukin-5 Antagonists (PHASE1)
• Efficacy of Reslizumab Dose Escalation in Patients With Severe Asthma (PHASE4)
• Comparison of Biologicals in Treatment of Severe Asthma
• Fluctuation Analyses of Asthma Patients With Biologics Use
• A Study of Reslizumab in Patients 12 Years of Age and Older With Severe Eosinophilic Asthma (PHASE3)
• Reslizumab to Prevent Post-treatment Eosinophilia in Loiasis (PHASE2)

Primary sources

Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.

Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:

• Cinqair CI brief — competitive landscape report
• Cinqair updates RSS · CI watch RSS
• Teva Respiratory Llc portfolio CI