Vaccine development typically goes through several phases, each designed to assess the safety, efficacy, and immunogenicity of the vaccine candidate. Here are the general phases of vaccine development:
- Exploratory/Preclinical Stage:
- Scientists identify and characterise potential antigens that could be used in the vaccine.
- Initial testing is done in the laboratory to understand the basic characteristics and immune response.
- Preclinical Testing:
- The vaccine candidate is tested on animals (usually mice/monkeys) to evaluate safety and immune response and to determine the appropriate dosage for the vaccine.
- Investigational New Drug (IND) Application:
- Researchers submit an IND application to regulatory authorities for permission to test the vaccine in humans.
- Clinical Development (Human Trials):
- Phase 1 - Safety and Dosage: Small groups of healthy volunteers receive the vaccine to assess safety, dosage, and initial immune response.
- Phase 2 - Expanded Trials: The vaccine is given to a larger group to further evaluate safety, immunogenicity, and dosage.
- Phase 3 - Efficacy: A larger-scale study involving thousands of participants to assess the vaccine’s efficacy, safety, and potential side effects.
- Regulatory Review and Approval:
- Researchers submit comprehensive data to regulatory agencies for review. Regulatory authorities decide whether to approve the vaccine for public use.
- Manufacturing and Quality Control:
- If approved, the vaccine is produced on a larger scale.
- Post-Marketing Surveillance (Phase 4):
- Continuous monitoring of the vaccine’s safety and effectiveness once it is available to the public.
- Adjustments or improvements may be made based on real-world data.