A sandwich ELISA for the quantification of the anticancer peptide CIGB-552 in human plasma

CIGB-552 is a synthetic anticancer peptide that has been evaluated in vitro and in vivo in lung and colon cancer models. To optimize therapy in the clinic, pharmacokinetic studies are necessary. Previously, a sandwich-type enzyme-linked immunosorbent assay (ELISA) had been developed by our working group for the quantification of CIGB-552 in biological matrices. The objective of this work was to carry out the full validation of the ELISA to support its application in clinical trials. First, we obtained a polyclonal antibody specific for CIGB-552 and with purity greater than 95 %. The lower limit of quantification and the upper limit of quantification were 3125 ng/ml and 200 ng/ml, respectively. The method is exact and precise in the quantification of the peptide with relative error and coefficient of variation values less than 20 %. The ELISA is specific in the presence of CIGB-552 metabolites in the sample, and also presents robustness to certain protocol variations. In summary, the validated ELISA meets the requirements for its application in upcoming clinical trials as part of pharmacokinetic studies.