Adalimumab
Adalimumab, a biologic. Fully human IgG1 mAb binding soluble and membrane-bound TNFα → neutralises TNF-mediated pro-inflammatory… Subcutaneous half-life 13 d.
Fully human IgG1 mAb binding soluble and membrane-bound TNFα → neutralises TNF-mediated pro-inflammatory signalling through TNFR1/2. First fully human therapeutic antibody (phage-display discovery). Clinical impact spans rheumatology, dermatology, and gastroenterology. Once the world's best-selling drug; multiple biosimilars now available.
V_L 5.6 REMOVED as an R6 stored default — 0.08 L/kg x 70 kg is the consumer default for a protein at MW >= 10 kDa. PMID:27965661 reports AUC0-inf, Cmax and AUC0-last and states no volume of distribution at all. The Humira label does give one, but as a RANGE from an IV arm in RA patients — "The distribution volume (Vss) ranged from 4.7 to 6.0 L" — which contains 5.6 without stating it, and pairing an IV Vss with this SC route would be a second defect. Removal is numerically a no-op. PK: ABSORPTION RATE AUTHORED FROM THE HUMIRA LABEL. This row carried no ka, so the solver substituted 1.0/h and put the peak at 6.1 h. Source, verbatim from the current FDA label (DailyMed setid 4977567e-3525-44ac-9ff5-f1e74b053950): "The mean time to reach the maximum concentration was 5.5 days (131 ± 56 hours)" — a point value with its spread, after a single 40 mg subcutaneous dose. The same section corroborates the record independently: "The average absolute bioavailability of adalimumab ... was 64%" and a terminal half-life "ranging from 10 to 20 days", which contains the stored 13 days. PUBMED HAS THIS NOWHERE — 27 targeted searches across two passes returned four usable peak times for this whole class, because Tmax is a label figure that rarely reaches an abstract. A regulatory label is already a first-class source in this schema. With the stored half-life fixing ke, Tmax solves uniquely for ka by inverting the model own definition, ln(ka/ke)/(ka-ke) = Tmax — ARITHMETIC, NOT AN ESTIMATE — giving 0.01833/h, which reproduces 131 h on substitution. EXPOSURE IS UNCHANGED: the absorption rate cancels out of AUC, so only the shape moves.
Pharmacokinetics
- Subcutaneous — t½ 13.0 d · F 64% · ka 0.01833 h⁻¹
Sources: PMID:24831559, PMID:20519961