PHYSICOCHEMICAL PROPERTIES of active compound DRUG DELIVERY SYSTEM for human testing are DEVELOPED Animal testing→ ADME in living system (may be corrected) Possible side effects and toxicities (same with human, min. of 2 weeks)→ 1 RODENT, 1 NON-RODENT ADMINISTRATION: Animals same route of dosage form with humans ANIMAL SAFETY TESTING: highest no-effect dose, plasma concentrations