Erenumab
Erenumab, a biologic. Fully human IgG2 mAb binding the canonical CGRP receptor (CLR/RAMP1 complex) on trigeminal sensory nerves and… Subcutaneous half-life 21 d.
Fully human IgG2 mAb binding the canonical CGRP receptor (CLR/RAMP1 complex) on trigeminal sensory nerves and cerebral vasculature → blocks CGRP-mediated vasodilation and neuropeptide release in the migraine cascade. Differs from the other approved CGRP mAbs which target the ligand. ~50% of patients achieve ≥50% reduction in migraine days.
PK: ABSORPTION RATE AUTHORED FROM OPEN-ACCESS FULL TEXT (PMC8252052). This row carried no ka, so the solver substituted 1.0/h and put the peak at 6.6 h. Verbatim: "Following a single dose of erenumab or galcanezumab, peak plasma concentrations are attained in approximately 5-6 days and their elimination half-lives are in the range of 27-28 days." A BACKGROUND STATEMENT rather than this study own measurement, and it is used because it CROSS-CHECKS: the galcanezumab half of the same sentence matches the EMGALITY label exactly at 5 days, and the 27-28 day half-life range contains this record stored 21 days. 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 0.02581/h, which reproduces 120 h on substitution. EXPOSURE IS UNCHANGED: the absorption rate cancels out of AUC, so only the shape moves.
Pharmacokinetics
- Subcutaneous — t½ 21.0 d · F 82% · ka 0.02581 h⁻¹ · Vd 3.5 L
Sources: PMID:28593473, PMID:26559125, PMID:33818780