tezepelumab

Brand: Tezspire

Prototype Drug
Drug Class: biologic — anti-thymic stromal lymphopoietin (anti-TSLP) monoclonal antibody
Drug Family: biologic
Subclass: epithelial cytokine inhibitor — upstream biologic for asthma
Organ Systems: respiratoryimmunology

Mechanism of Action

Fully human IgG2 lambda monoclonal antibody that binds TSLP, an epithelial cytokine released in response to allergens, pollutants, and infectious triggers; TSLP blockade prevents downstream activation of dendritic cells, innate lymphoid cells, mast cells, basophils, and eosinophils, suppressing all major inflammatory pathways in asthma regardless of phenotype.

thymic stromal lymphopoietin (TSLP)

Indications

  • severe uncontrolled asthma as add-on maintenance therapy (adults and adolescents 12 years and older)
  • effective in eosinophilic and non-eosinophilic asthma phenotypes

Contraindications

  • hypersensitivity to tezepelumab
  • acute asthma exacerbation (not rescue therapy)

Adverse Effects

Common

  • pharyngitis
  • arthralgia
  • injection site reactions
  • back pain

Serious

  • hypersensitivity reactions (rare)
  • helminth infections (theoretical based on mechanism)

Pharmacokinetics (ADME)

Absorption subcutaneous injection; bioavailability approximately 77%; Tmax approximately 3-10 days
Distribution Vd approximately 4.5 L
Metabolism proteolytic degradation to amino acids
Excretion proteolytic catabolism
Half-life approximately 26 days
Onset clinical exacerbation reduction over weeks to months
Peak approximately 3-10 days
Duration once every 4 weeks subcutaneous injection
Protein Binding N/A
Vd approximately 4.5 L

Drug Interactions

Drug / Agent Mechanism Severity
live vaccines potential immune interference; avoid live vaccines moderate

Nursing Considerations

  1. Administer 210 mg subcutaneously every 4 weeks; allow to reach room temperature for 30 minutes before administration; inject in abdomen, thigh, or upper arm with rotation of sites.
  2. Unlike anti-IL-5 biologics, tezepelumab does not require baseline blood eosinophil count to predict response; it is effective across all asthma inflammatory phenotypes including non-eosinophilic asthma.
  3. Observe patients for hypersensitivity reactions after administration; symptoms typically occur within hours of injection; ensure epinephrine is accessible.
  4. Emphasize that tezepelumab is an add-on maintenance medication and does not replace ICS, LABA, or rescue SABA; instruct patients on the continuing need for rescue therapy.

Clinical Pearls

  • Tezepelumab is the first FDA-approved biologic that targets TSLP, an upstream 'master switch' cytokine; by blocking the initial epithelial alarm signal, it reduces multiple downstream inflammatory cascades simultaneously — including eosinophilic, Th2, and non-Th2 pathways.
  • Unlike anti-IL-5 agents (mepolizumab, benralizumab, reslizumab) which require eosinophilic phenotype for efficacy, tezepelumab demonstrated significant exacerbation reduction in patients with low eosinophil counts — expanding the eligible population to non-eosinophilic asthma.

Safety Profile

Pregnancy avoid
Lactation insufficient-data
Renal Adjustment Not required
Hepatic Adjustment Not required
TDM Not required
Guideline Update pending