Active Pharmaceutical Ingredient(API)
The substance in a pharmaceutical drug that is biologically active and produces the intended therapeutic effect.
Usage Examples
- The API is manufactured at a GMP-certified facility in Ireland.
- API specifications include limits for five specified impurities.
- Process validation demonstrated consistent API quality.
What is API?
The Active Pharmaceutical Ingredient (API), also called drug substance, is the substance in a drug product responsible for the physiological or pharmacological action. APIs must meet strict quality standards for identity, purity, strength, and quality.
API manufacturing involves synthesis (chemical or biological), purification, and characterization. Critical Quality Attributes (CQAs) include potency, impurity profile, polymorphic form, particle size, and residual solvents.
Module 3.2.S of the CTD contains comprehensive API information including manufacturing process, controls, specifications, and stability data. API manufacturers often maintain Drug Master Files (DMFs) containing proprietary information.
Regulatory Context
This term appears most often in cmc & manufacturing workflows where submission quality, regulatory evidence, and audit readiness depend on consistent language. It is commonly referenced alongside ICH Q7, ICH Q11, 21 CFR 211.
When This Matters
- The API is manufactured at a GMP-certified facility in Ireland.
- API specifications include limits for five specified impurities.
- Process validation demonstrated consistent API quality.
Common Mistakes
- Failing to align CMC change narratives with current CFR/ICH expectations.
- Submitting incomplete control strategy documentation.
- Separating manufacturing and regulatory review cycles too late in execution.
Related Regulations
Frequently Asked Questions
API (drug substance) is the active ingredient itself. Drug product is the final dosage form containing the API plus excipients (e.g., tablets, capsules, injections).
ICH Q7 (Good Manufacturing Practice for APIs) covers API manufacturing. ICH Q11 covers API development and manufacturing information for regulatory submissions.
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Sources & References
