Baricitinib
Baricitinib. JAK1/JAK2 inhibitor — blocks cytokine receptor signaling. Approved for rheumatoid arthritis, atopic dermatitis, alopecia areata, and… Oral half-life 12 h.
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.
PK PROVENANCE, moved here from source_label when that field was shortened to a citation that names the label revision: Olumiant (baricitinib) prescribing information — V, F, ka and half-life are label-grade. No PubMed abstract states any of them, and the previously cited study states none of them either; it remains in refs[] for the clearance and Tmax it does report. PK: ZERO OF FOUR FIELDS ARE SUPPORTED ANYWHERE IN PUBMED, and no fix is available. Four separate searches — absolute bioavailability, volume of distribution, elimination half-life, absorption rate constant — return COUNT 0 or nothing usable, and the cited paper, which is a genuine healthy-volunteer PK/PD study, states none of ka 1.4, V 76, F 0.79 or t-half 12. What it does state exposes a CLASS 12 DEFECT: the stored set implies CL/F 5.56 L/h against that paper own "low oral-dose clearance (17 L/h)", a 3.06-fold disagreement, so this record OVER-PREDICTS BARICITINIB EXPOSURE ABOUT THREEFOLD. The cause is that 76 L is a volume from a bi-exponential fit — the abstract says concentrations "decline in a bi-exponential fashion" — paired with that fit terminal half-life and fed to a one-compartment solver. Reproducing 17 L/h at 12 h would need V/F 294 L, which is verbatim nowhere. The label triple is kept, its false provenance is stripped, and the error is logged rather than closed with an invented number. A 99.42 L volume in the literature is n=1, critically ill and on haemofiltration.
Pharmacokinetics
- Oral — t½ 12 h · F 79% · ka 4.388 h⁻¹ · Vd 76 L
Sources: PMID:24965573, PMID:20363976