Drug quality evaluation and control involve extensive use of biological methods in addition to chemical, physico-chemical and microbiological ones in order to ensure drug identity, purity and safety. Basic requirements for biological testing criteria are stated in the State Pharmacopoeia of the Russian Federation, however some aspects of testing are not described in sufficient detail and depend on the nature of a medicine to be tested. The present article describes basic requirements for introducing «Bacterial endotoxins» and «Abnormal toxicity» parameters to normative documentation. It also outlines basic aspects of test conditions validation and determination of an adequate level of drug quality standards