Half-lives of VWFpp and VWF:Ag after administration of desmopressin. The half-lives of VWFpp and VWF were determined by calculation of the first-order rate constant for the elimination phase from the slope of the VWF:Ag or VWFpp concentration against time as described. The box extends from the 25th to 75th percentile, with a line at the median. The whiskers extend to the highest and lowest values determined. The half-life of VWFpp in most patients fell within the reported normal range. The half-live of VWF:Ag in individuals varied considerably ranging from markedly decreased to normal values. The median VWF half-life fell below the reported normal range.