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CP690,550

Pfizer · Phase 3 active Small molecule

CP690,550 is a JAK inhibitor that selectively blocks Janus kinase signaling to reduce inflammatory cytokine production and immune cell activation.

CP690,550 is a JAK inhibitor that selectively blocks Janus kinase signaling to reduce inflammatory cytokine production and immune cell activation. Used for Rheumatoid arthritis, Ulcerative colitis, Psoriasis.

At a glance

Generic nameCP690,550
SponsorPfizer
Drug classJAK inhibitor
TargetJAK1, JAK3
ModalitySmall molecule
Therapeutic areaImmunology
PhasePhase 3

Mechanism of action

CP690,550 (tofacitinib) inhibits JAK1 and JAK3 kinases, which are critical for signal transduction downstream of cytokine receptors involved in immune and inflammatory responses. By blocking JAK signaling, the drug reduces the production of pro-inflammatory cytokines and suppresses T-cell proliferation and activation, thereby dampening pathological immune responses in autoimmune and inflammatory conditions.

Approved indications

Common side effects

Key clinical trials

Primary sources

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

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