Baricitinib

Category: pharmacological

Aliases: Olumiant

Pharmacological Mechanism

JAK1/JAK2 inhibitor — blocks cytokine receptor signaling. Approved for rheumatoid arthritis, atopic dermatitis, alopecia areata, and adjunct in COVID-19 hospitalization. Class effects: infections, MI, malignancy, thrombosis.

Half-Life (t½)

PO: 12h

Dosing Guidelines

• PO: Typical 2 mg (Range: 1–4 mg)

Target Organ Systems

• cardiovascular
• integumentary
• immune-hematologic

Pathways It Modulates

• Calcineurin / NFAT T-cell activation (inhibitor) — JAK1/2
• CD4 T-helper differentiation (inhibitor) — JAK1/2 → IFN + IL-6 axis
• cGAS-STING cytosolic DNA sensing → type I IFN (inhibitor) — JAK1/2 (downstream IFN; approved for COVID + alopecia areata + interferonopathies)
• JAK-STAT signaling (inhibitor) — JAK1 + JAK2 (RA, alopecia areata)
• Neuroinflammation (inhibitor) — JAK1/2 → ↓IFN signature (used in CANDLE/SAVI interferonopathies)

Chemical Identifiers

• PubChem CID: 44205240
• Formula: C16H17N7O2S
• Molecular weight: 371.42 g/mol
• InChIKey: XUZMWHLSFXCVMG-UHFFFAOYSA-N
• SMILES: CCS(=O)(=O)N1CC(C1)(CC#N)N2C=C(C=N2)C3=C4C=CNC4=NC=N3

References

• PMID 24965573
• PMID 20363976