Dried blood spots reduce cost of drug development

Dr. Rudi Segers, Eurofins Global Central Laboratory, The Netherlands

Dried blood spots (DBS) refers to a blood sampling technique where small volumes of blood are spotted on an appropriate filter paper, dried and taken to the laboratory for analysis. The technique is well established in clinical labs for applications, such as neonatal screening for inborn diseases, but has recently experienced a surge of interest in the context of drug development, i.e. toxicokinetic (TK) and pharmacokinetic (PK) studies, biomarker assays and therapeutic drug monitoring.

DBS as a low volume blood sampling technique was introduced in 1963 in the context of neonatal screening of phenylketonurea. Much more recent is the use of DBS in drug development spurred by the ethical advantages of requiring lower blood volumes and fewer animals in the case of preclinical studies. Cost savings are also made by the simple shipment of DBS cards compared to the cumbersome dry ice sample shipment.

A rapidly increasing number of bioanalytical methods have been published, underlining the fact that many companies are now considering DBS in at least some part of the development cycle of their drugs. At the same time, not all questions have been answered, and some contentious issues remain, e.g. how best to introduce the internal standard and the impact of hematocrit on the assay result. It can also be expected that the workflow in the lab will be much improved over the years to come as various technological advances are under way at the level of sampling from the DBS cards as well as automation.

At this point, no company is sufficiently advanced to have obtained market authorisation for their compound from the FDA based on DBS. Regulatory authorities have reacted enthusiastically, but cautiously.

DBS offers a new opportunity for drug developers. Eurofins is already helping some of them with PK and pediatric applications, both in our clinic and in our bioanalytical labs.

It can be expected that the technology will see increasing use in pediatric studies and therapeutic drug monitoring. Further ramifications to large molecule applications (biomarkers PK and immunogenicity of biologicals) are also on the horizon.

Contact: bioanalysis@eurofins.com