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Comparator: cetirizine

Organon and Co · Phase 3 active Small molecule

Cetirizine is a selective H1-receptor antagonist that blocks histamine-mediated allergic responses without significant central nervous system penetration.

Cetirizine is a selective H1-receptor antagonist that blocks histamine-mediated allergic responses without significant central nervous system penetration. Used for Allergic rhinitis (seasonal and perennial), Chronic urticaria, Allergic conjunctivitis.

At a glance

Generic nameComparator: cetirizine
SponsorOrganon and Co
Drug classSelective H1-receptor antagonist (second-generation antihistamine)
TargetH1 histamine receptor
ModalitySmall molecule
Therapeutic areaImmunology / Allergy
PhasePhase 3

Mechanism of action

Cetirizine competitively binds to peripheral H1 histamine receptors on mast cells, basophils, and other immune cells, preventing histamine from triggering allergic cascade reactions. Due to its hydrophilic nature and low lipophilicity, it has minimal blood-brain barrier penetration, resulting in reduced sedation compared to first-generation antihistamines. This mechanism provides symptomatic relief of allergic rhinitis, urticaria, and other histamine-mediated allergic conditions.

Approved indications

Common side effects

Key clinical trials

Primary sources

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SourceUsed for
ClinicalTrials.govTrial enrolment, design, endpoints, results