Comparison of two radioimmunoassays and a microbiologic assay for bleomycin

Recently two radioimmunoassays have been independently developed for determination of bleomycin levels. In this study these assays are compared with each other and with a standard microbiologic assay for bleomycin. Bleomycin levels were determined in serum and urine samples obtained at varying intervals following intramuscular bleomycin injection. There were systematic differences between the assays. One radioimmunoassay indicated bleomycin levels lower than the levels indicated by the microbiologic assay with serum samples. With urine samples, both radioimmunoassays indicated bleomycin levels greater than the microbiologic assay.