Toxicology

Toxicology

• Toxicology is the study of the adverse effects of chemicals on living organisms.
• In drug development, toxicological studies assess the potential harmful effects of drug candidates.

Types of Toxicity Studies

1. Acute Toxicity

   • Objective: Determine the effects of a single dose.
   • Endpoints: Lethal dose (LD50), clinical signs, organ toxicity.

2. Repeated Dose Toxicity

   • Subacute (up to 28 days) and Subchronic (up to 90 days)
   • Objective: Assess effects of repeated dosing over time.
   • Endpoints: Clinical observations, hematology, clinical chemistry, histopathology.

3. Chronic Toxicity

   • Duration: Typically, longer than 90 days, up to 1 year or more.
   • Objective: Identify long-term effects.

4. Genotoxicity

   • Tests: Ames test, micronucleus test, chromosomal aberration tests.
   • Objective: Detect mutations, chromosomal damage.

5. Carcinogenicity

   • Objective: Assess potential to cause cancer.
   • Duration: Long-term studies, often in rodents.

6. Reproductive and Developmental Toxicity

   • Segments:
     • Segment I: Fertility and early embryonic development.
     • Segment II: Embryo-fetal development (teratogenicity).
     • Segment III: Pre- and postnatal development.

7. Immunotoxicity

   • Objective: Evaluate effects on the immune system.

8. Local Tolerance

   • Objective: Assess irritation or sensitization at administration sites.

Regulatory Guidelines

• ICH M3(R2): Guidance on non-clinical safety studies.
• OECD Guidelines: Standardized methods for toxicology testing.

Click Here to Watch the Best Pharma Videos