Clinical and Pre-Clinical Application

    DBS significantly simplifies sample collection and handling in clinical studies. Sample drawing is minimally invasive and enables access to more samples in terms of amount and location. The low sample amount required is a strong advantage for pre-clinical application supporting the 3R requirements.

The pre-clinical and clinical market summarizes the testing of new pharmaceuticals in animal (pre-clinical) and human (clinical) studies. The main advantage in pre-clinical studies is the reduced number of test animals (due to the need for lower blood volumes) which is in accordance with the 3R requirement of animal studies (replacement, reduction, refinement) [1]. Drugs can be studied on a single mouse over several time points, whereas several mice are required with conventional methods. In clinical studies, there is an ease in sampling and more patient comfort.

The DBS technology offers huge advantages here, however has not been fully accepted by regulatory bodies so far [2]. The major reason for this is the hematocrit effect based on different blood viscosity. If a sub-punch is taken and the hematocrit value and the volume is unknown, an analytical error may result. However, this only results in a significant error if the hematocrit value is outside of the normal range (40 to 54% for men and 36 to 48% for women [3]) of a healthy patient. Also, in most clinical studies the patient hematocrit value is known.

The trend towards micro sampling is shaping this market, and more and more applications can be found in literature.

[1] R. V Oliveira, J. Henion, and E. R. Wickremsinhe, “Automated high-capacity on-line extraction and bioanalysis of dried blood spot samples using liquid chromatography/high-resolution accurate mass spectrometry.,” Rapid Commun. Mass Spectrom., vol. 28, no. 22, pp. 2415–26, Nov. 2014.

[2] N. Ganz, M. Singrasa, L. Nicolas, M. Gutierrez, J. Dingemanse, W. Döbelin, and M. Glinski, “Development and validation of a fully automated online human dried blood spot analysis of bosentan and its metabolites using the Sample Card And Prep DBS System.,” J. Chromatogr. B. Analyt. Technol. Biomed. Life Sci., vol. 885–886, pp. 50–60, Feb. 2012.

[3] H. Walker, W. Hall, and J. Hurst, Clinical Methods: The History, Physical, and Laboratory Examinations, 3rd editio. 1990.