Drug toxicological evaluation

Drug toxicological evaluation


1. Single dose toxicity test: acute toxicity refers to the toxic effect or even death caused by one contact or multiple contact with a chemical substance within 24 hours. In a narrow sense, single dose toxicity study is to investigate the acute toxicity produced by experimental animals after a single dose of test substance.

In the process of new drug research, its safety evaluation is put in the first place. It is very important to clarify the drug action target and its toxicity in preclinical research. Drugs intended for human body usually need a single dose toxicity test. The information obtained from single dose toxicity test has important reference value for the dose design of repeated dose toxicity test and the selection of starting dose of some drug clinical trials, and can provide some information related to acute poisoning caused by human drug overdose.       

List of service items for single dose toxicity test

Experimental typeExperimental animalTest substanceExposure routes
Acute toxicity testRodents        Chemical drugs, natural drugs,          traditional Chinese MedicineOral, percutaneous and injection       exposure
Note: in principle, the route of exposure should be consistent with the route proposed for clinical use


2. Repeated administration toxicity test: repeated administration toxicity test is to describe the toxic reaction of experimental animals after repeated acceptance of test substance. It is an important content of non clinical safety evaluation. By observing the changes of general physiological indexes, hematology, hematuria biochemistry, pathological indexes and some specific indexes of experimental animals, the repeated administration toxicity test can: ① predict the possible clinical adverse reactions caused by the test substance, including the nature, degree, dose-effect and time-effect relationship of adverse reactions, reversibility, etc; ② Determine the toxic target organ or target tissue of the repeated administration of the test substance; ③ If possible, determine the dose level of no observed adverse effect (NOAEL); ④ Speculate the initial dose of the first clinical trial (first in human, FIH) to provide a safe dose range for subsequent clinical trials; ⑤ provide reference for clinical adverse reaction monitoring and prevention.


      List of repeated administration toxicity test service items

Experimental typeExperimental animalTest substanceExposure routes
Subchronic toxicity testRodents        Chemical drugs, natural drugs,          traditional Chinese MedicineOral, percutaneous and injection       exposure
Chronic toxicity test
Carcinogenic test
Note: in principle, the route of exposure should be consistent with the route proposed for clinical use


3. Local toxicity test: the test object causes damage to the direct contact part of the body.

       3.1 Skin irritation test: local reversible inflammatory reaction after skin contact with the test object, including single and multiple skin irritation tests, intact skin and damaged skin irritation tests, etc. the end point of observation is skin irritation and skin corrosion. Skin corrosion is local irreversible tissue damage of skin.

       3.2 Skin sensitization test: the skin produces immunogenic reaction to the test object. This kind of test can be carried out in the open or wrapped state after skin coating. The liquid test object can be coated or injected subcutaneously in a small amount. The powder or semi-solid test object shall be exposed in a closed manner with appropriate solvent or shaping agent.

       3.3 Muscle irritation test: in order to ensure the safety and effectiveness of clinical use of intramuscular injection drugs such as injection and injection powder, the local stimulation test of the drug on the muscle at the injection site is mainly used to investigate whether the drug causes irritation symptoms such as redness, congestion, degeneration and death to the muscle tissue, so as to determine the local toxicity intensity of the injection, It is proposed to take appropriate measures to reduce or eliminate its stimulation.

      3.4 Eye irritation test: the reversible inflammatory reaction caused by the exposure of the test object on the surface of the eye. Generally, this test is not required for strong acid and alkali substances that irritate the skin. This test should be carried out separately for most chemical substances with pH close to neutral.


List of service items for local administration toxicity test

Experimental typeExperimental animalTest substanceExposure routes
Skin irritation testGavy, rabbit        Chemical drugs, natural drugs,          traditional Chinese MedicinePatch

Skin sensitization test

     Skin coating or subcutaneous             injection
Muscle / eye irritation testInjection / drip