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Placebo/CP-690,550

Pfizer · Phase 3 active Small molecule

CP-690,550 is a JAK inhibitor that blocks Janus kinase signaling to reduce inflammatory immune responses.

CP-690,550 is a JAK inhibitor that blocks Janus kinase signaling to reduce inflammatory immune responses. Used for Rheumatoid arthritis, Ulcerative colitis, Psoriasis.

At a glance

Generic namePlacebo/CP-690,550
SponsorPfizer
Drug classJAK inhibitor
TargetJAK1, JAK3
ModalitySmall molecule
Therapeutic areaImmunology
PhasePhase 3

Mechanism of action

CP-690,550 (tofacitinib) selectively inhibits JAK1 and JAK3 kinases, which are critical for cytokine signaling in T cells and other immune cells. By blocking these kinases, the drug suppresses the production of pro-inflammatory cytokines and reduces pathogenic T cell activation, thereby dampening autoimmune and inflammatory responses.

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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