Omalizumab (Xolair)

Biologicprescriptionsubcutaneous · inferred

Humanized IgG1 monoclonal antibody binding free IgE and preventing IgE-FceRI engagement on mast cells and basophils. Approved for moderate-to-severe persistent allergic asthma, chronic spontaneous urticaria, chronic rhinosinusitis with nasal polyps, and food allergy. Asthma dosing by body weight and total serum IgE (75-375 mg SC every 2-4 weeks); CSU 150-300 mg monthly. Biphasic PK with terminal half-life ~26 days. SC bioavailability ~62%. Boxed warning: rare anaphylaxis post-administration.

Projected serum levels — 300 mg, custom (shown daily)

Omalizumab (Xolair)
Omalizumab (Xolair) modeled serum levels, 300 mg custom (shown daily) over 121 days Population-based pharmacokinetic estimate. Steady state reached after approximately 108 days. 0 2.5k 5k 7.5k 10k Day 0 Day 30 Day 61 Day 91 Day 121 Time on a regular schedule ≈ steady state · day 108
Omalizumab (Xolair) modeled serum levels with a loading dose of 900 mg, then 300 mg custom (shown daily) The first dose is larger so levels approach steady state faster. 0 2.5k 5k 7.5k 10k Day 0 Day 30 Day 61 Day 91 Day 121 Time on a regular schedule

Maintenance schedule: 300 mg custom (shown daily) (subcutaneous).

Loading schedule: 900 mg on day 1, then 300 mg custom (shown daily) — reaching therapeutic levels sooner.

Modeled steady state after ~108 days: peak ≈ 7.6k mg, trough ≈ 7.6k mg body load. Population-based estimate over 121 days for a 300 mg dose at a 70 kg reference body mass — the interactive app scales curves to your doses, timing, and body mass.

Key facts

Category
Biologic
Route modeled
Subcutaneous
Model confidence
inferred
Half-life
26 days
Common dose
300 mg
Suggested maximum
375 mg/day
Reference dose range
150–375 mg (single dose)
Suggested cadence
custom (shown daily)

Research behind this entry

  1. A mechanism-based binding model for the population pharmacokinetics and pharmacodynamics of omalizumab Hayashi N et al. · British Journal of Clinical Pharmacology, 2007 DOI

    Mechanistic PK/PD model quantifying omalizumab-IgE binding kinetics and disposition; supports dose-by-weight-and-IgE nomogram.

  2. Efficacy and safety of a recombinant anti-immunoglobulin E antibody (omalizumab) in severe allergic asthma Holgate ST et al. · Clinical & Experimental Allergy, 2004 DOI

    Pivotal efficacy trial demonstrating reduced exacerbations and improved symptom control with omalizumab in severe allergic asthma.

2 published studies referenced in the app, each with a plain-language summary.