1) Where biologics fit in GINA stepwise treatment

1. Diagnosis is truly asthma
2. Inhaler technique/adherence are good
3. Comorbidities and triggers addressed
4. Optimized high-dose ICS-LABA ± add-ons (LAMA, etc.) still inadequate control or frequent exacerbations
5. Phenotyping done (Type 2 vs non-Type 2 features)

2) GINA concept: phenotype-directed biologic selection

Type 2 inflammation indicators (any combination)

• Blood eosinophils elevated
• FeNO elevated
• Allergen-driven disease / IgE sensitization
• Need for maintenance oral corticosteroids (OCS)
• Frequent severe exacerbations despite optimized inhaled therapy

3) Available biologics and exam-essential points

A) Anti-IgE: Omalizumab

• Target: free IgE
• Best for: severe allergic asthma with sensitization and qualifying IgE range/weight criteria
• Use: add-on in patients with recurrent exacerbations despite high-intensity inhaled therapy
• Route: SC (typically every 2–4 weeks, dose by IgE and weight)
• Benefits: reduces exacerbations, may reduce steroid need, improves control in eligible allergic phenotype
• Exam pearl: needs evidence of allergen sensitization + IgE criteria

B) Anti-IL5: Mepolizumab, Reslizumab

• Target: IL-5 pathway (eosinophil maturation/survival)
• Best for: severe eosinophilic asthma
• Mepolizumab: SC (usually q4w)
• Reslizumab: IV, weight-based (less commonly used in many regions)
• Benefits: fewer exacerbations, OCS-sparing, improves eosinophilic disease control

C) Anti-IL5Rα: Benralizumab

• Target: IL-5 receptor alpha (causes near-complete eosinophil depletion)
• Best for: severe eosinophilic asthma, especially high eosinophils/frequent exacerbators
• Route: SC (q4w initially, then q8w maintenance in common regimens)
• Benefits: strong exacerbation reduction, OCS-sparing, convenient maintenance interval

D) Anti-IL4Rα: Dupilumab

• Target: IL-4 receptor alpha (blocks IL-4/IL-13 signaling)
• Best for: Type 2 asthma (eosinophilic and/or high FeNO), OCS-dependent asthma
• Route: SC (loading then maintenance every 2 weeks in common regimens)
• Benefits: reduces exacerbations, improves lung function, meaningful OCS reduction in steroid-dependent asthma
• Additional clue: useful where comorbid Type 2 diseases coexist (e.g., atopic dermatitis, CRSwNP)

E) Anti-TSLP: Tezepelumab

• Target: TSLP (upstream epithelial “alarmin”)
• Best for: severe uncontrolled asthma across phenotypes, including lower biomarker groups (though response often better with Type 2 signals)
• Route: SC (typically q4w)
• Benefits: broad exacerbation reduction; option when classic Type 2 biologic criteria are not strongly met

4) Practical GINA-style biologic eligibility checklist (exam-ready)

• Severe asthma despite optimized high-dose ICS-LABA
• Frequent severe exacerbations (or maintenance OCS dependence)
• Phenotype-specific criteria:
  • Allergic sensitization/IgE profile for omalizumab
  • Elevated eosinophils for anti-IL5/IL5R choices
  • Type 2 markers (eosinophils/FeNO) for dupilumab
  • Broader uncontrolled severe asthma profile for tezepelumab
• Exclusion of modifiable causes of poor control (adherence, technique, smoking, comorbidities)

5) How to choose between biologics (viva algorithm)

1. Allergic + IgE-eligible -> consider omalizumab
2. Eosinophilic predominant -> mepolizumab/benralizumab (± reslizumab where available)
3. Type 2 high or OCS-dependent -> dupilumab strong option
4. No clear Type 2 pattern or mixed phenotype with frequent exacerbations -> tezepelumab can be considered
5. Consider:
   • Dosing frequency/preference
   • Age approvals/local labeling
   • Comorbidities
   • Prior biologic response/failure
   • Cost/access

6) Assessing response after initiation (very important in exams)

• Exacerbation rate reduction
• Symptom control (ACT/ACQ), reliever need
• Lung function (FEV1 trends)
• OCS dose reduction (if OCS-dependent)
• Biomarker trend (supportive, not sole determinant)
• Adverse effects and patient satisfaction

7) Safety and monitoring points

• Injection-site reactions, hypersensitivity possible with all
• Anaphylaxis risk is uncommon but important (classically emphasized with omalizumab)
• Monitor asthma control regularly; biologics are add-on, not replacement for all background therapy initially
• Taper OCS carefully where possible to avoid adrenal issues
• Vaccination and parasitic infection considerations may apply depending on agent/context

8) High-yield comparison table

9) MD exam “rapid-fire” points

• Biologics are for severe uncontrolled asthma at Step 5
• Always optimize basics before labeling severe refractory asthma
• Phenotype + biomarkers + exacerbation history guide selection
• Trial then review response in a few months
• If non-response, switch mechanism, don’t persist blindly
• Aim includes exacerbation prevention and OCS minimization

1. a one-page mnemonic sheet for all asthma biologics, or
2. a case-based viva simulation (e.g., eos 450, FeNO 45, 3 exacerbations/year -> best biologic and why).