Is serum copeptin a modifiable biomarker in autosomal dominant polycystic kidney disease?

Table 2 Summary of vasopressin limitations compared to copeptin advantages as a biomarker using the thermo scientific B.R.A.H.M.S KRYPTOR assay (adapted from Thermo Fisher scientific)

Features	Limitations of measuring AVP	Advantages of CT-proAVP (Copeptin)
Ex vivo stability	Unstable (even at -20 °C)	Stable at > 3 d at room temperature
Sample volume required	400 L	50 μL
Time to results	3 working days	approximately 1 h
Sensitivity	Low (small molecule size, measured only by competitive immunoassay)	High (larger size, can be measured using a sensitive sandwich immunoassay)
Measuring range	1.15-73.8 pmol/L	0.7-500 pmol/L and up to 2000 pmol/L with automated dilution
Handling	Manual	Automatic

AVP: Arginine vasopressin.