In Stage 2 of drug testing, what is primarily tested on live animals?

In Stage 2 of drug testing, the primary focus is on evaluating the drug’s efficacy and toxicity. This stage typically involves administering the drug to live animals to observe its effects on biological systems. Researchers are interested in understanding how well the drug works (its efficacy) and identifying any harmful effects it may cause (its toxicity). This can help to inform whether the drug is likely to be safe and effective for use in humans before moving to clinical trials.

The assessment of drug efficacy involves determining the optimal dosage, the intended effects on the target condition, and any physiological responses to the drug. Toxicity testing is crucial to identify potential side effects and to understand the drug’s safety profile. Therefore, this stage is essential for minimizing risks before advancing to human trials, making it a critical part of the drug development process.