By Udbhav Bhargava
India’s drug regulator, the Central Drugs Standard Control Organization, has approved human clinical trials to be performed for ‘Covaxin’ This was the first indigenous Covid-19 vaccine candidate to obtain this approval. Such trials are expected to begin in July across India. The vaccine is being developed by the Bharat Biotech India (BBIL) and National Institute of Virology (NIV), Pune. The latter, with the assistance of Indian Council of Medical Research, isolated a strain of the virus from an asymptomatic Covid-19 patient and transferred it to BBIL. The vaccine is scheduled to launch on the 74th Independence Day.
There are 2 types of vaccines
- Live-attenuated vaccines
- Inactivated vaccines
Weakened (or attenuated) germ shape which causes a disease. Since these vaccines are so close to the natural infection that they help prevent, they build an immune response that is effective and enduring. Only 1 or 2 doses of the majority of live vaccines will provide protection against a germ and the illness it triggers for life.
Live vaccines are used to protect against: MMR combined vaccine
- Rotavirus
- Smallpox
- Chickenpox
- Yellow fever
Inactivated vaccines use the destroyed, disease-causing form of the germ. Inactivated vaccines typically do not have as high immunity (protection) as live vaccines-booster shots. Inactivated vaccines appear to have a better record of health. Inactivated vaccines are used to protect against:
- Hepatitis A
- Flu
- Polio
- Rabies
Vaccine Development – Explained
General stages of a vaccine’s growth process are 1. Stage 2 Exploratory. Phase 3 Pre-clinical. Clinical Evolution 4. Examination and approval of regulations5. Fabrication 6. Clinical development: Quality assurance
Clinical development is a process which takes three phases. Until being considered safe and appropriate for general use, new medications will move through all three stages of clinical trials. If the initial tests are successful, this Coronavirus vaccine may last 12 to 18 months until it is ready for public use.
Phase 1
Phase 1 trials evaluate a small number of people who undergo specific doses of an experimental drug, usually between 20 and 80. Researchers track how each volunteer metabolizes the given medication over the course of several months, and what specific side effects occur in response to various doses.
Phase 2
Phase 2 trials typically examine several hundred people and monitor participants for periods of from several months to two years. Primarily, Phase 2 trials serve as a secondary measure of safety and help researchers to refine the dosing of a particular medication. Researchers are currently selecting participants with characteristics, such as age and physical health, that match those of the people for whom the vaccine is being produced. Of example, although anyone may contract COVID-19, those of advanced age and those with chronic illnesses are more likely to experience serious symptoms and this should be seen in Phase 2 studies.
Phase 3
Stage 3 trials usually follow 300 to 3,000 participants in one to four years. Researchers can take note of unusual side effects of the drug with a larger group of people, and by extending the study period, they can catch long-term side effects as they arise. Phase 3 trials must show that a given medication offers the medical benefits it’s meant to.
Phase 4
Upon approval by the regulator, the company will constantly monitor the use of its vaccine on patients and apply reports of post-marketing surveillance, which will test for any possible adverse effects of the drug over the long term.
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