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FK199B

Astellas Pharma Inc · Phase 3 active Small molecule

FK199B is a selective antagonist of the complement C5a receptor that inhibits complement-mediated inflammation.

FK199B is a selective antagonist of the complement C5a receptor that inhibits complement-mediated inflammation. Used for Complement-mediated inflammatory disorders (specific indication under investigation in Phase 3).

At a glance

Generic nameFK199B
Also known asZolpidem MR Tablet
SponsorAstellas Pharma Inc
Drug classC5a receptor antagonist
TargetC5a receptor (C5aR)
ModalitySmall molecule
Therapeutic areaImmunology
PhasePhase 3

Mechanism of action

FK199B blocks the C5a receptor on immune cells, preventing the recruitment and activation of neutrophils and other inflammatory cells downstream of complement cascade activation. This mechanism reduces tissue damage and inflammation in complement-driven diseases. It represents a targeted approach to modulating innate immunity without broad immunosuppression.

Approved indications

Common side effects

No common side effects on file.

Key clinical trials

Primary sources

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

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