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COVID-19 Vaccine 
Information

Last update:

How Vaccines Work

How Vaccines Work

Weak Germs Injected

Vaccines contain the same germs that cause the disease, either killed or weakened, or they contain genetic instructions that code for the disease.

Immunity Developed

After getting vaccinated, one develops immunity to that disease without having to get it first.

Antibodies Created

They stimulate your immune system to produce antibodies, as if you were exposed to the germ.

Stages of Development

Stages of Development

Pre-Clinical

Initial tests of a potential treatment or vaccine are called “pre-clinical” (i.e., non-human testing). These generally include various tests done in the laboratory (in vitro tests) and studies conducted in animals (in vivo tests) to evaluate its potential to treat the disease.

I - Clinical Phase

  • Small study of healthy people

  • Evaluates safety and immune responce at different doses.

  • Typically takes 1-2 years, however, for COVID-19 trials, the estimated time is three months.

II - Clinical Phase

Clinical trials test a potential treatment or vaccine on a large (often up to several hundred) group of people who will use the drug (patients) or get vaccinated (healthy volunteers), looking at whether the treatment or vaccine is safe and whether it works effectively. Typically takes 2-3 years, however, for COVID-19 trials, expected to take eight months.

III - Clinical Phase

Clinical trials continue to test the safety and effectiveness of a treatment or vaccine but on a much larger scale, involving up to several thousand people. Typically takes 2-4 years, but for COVID-19 trials, may be combined with Phase II.

RR - Regulatory Review

  • Government agency reviews trial data and licensing application.

  • Can occur while manufacturing. 

  • Typically takes 2-4 years, but for COVID-19, expedited tp take a few months.

IV - Clinical Phase

  • Post-approval studies that monitor effectiveness in real-world conditions

  • Testing begins after vaccine has been released to public

Early Manufacturing

EARLY MANUFACTURING

Oftentimes developers will try to ensure that enough of a vaccine is ready to ship the moment approval comes in by beginning the manufacturing process during clinical trials.

But a manufacturer loses significant resources if approval doesn’t come or a vaccine is no longer needed in the marketplace. The more vaccines produced, the more risk incurred. To mitigate risk and encourage manufacturing, governments, industry and international organizations are working together.

PRE

I

II

III

RR

IV

Non-Ideal Case

  • Developer manufactures mass quantities of a vaccine, but does not get approval, leaving the public without a vaccine and resources put into manufacturing lost. For COVID-19 vaccine development, private philanthropy has pledged to pay the lost costs for this scenario.

PRE

I

II

III

RR

IV

Good Case

  • Developer gets fast approval, but has not manufactured enough of a vaccine to distribute in mass quantities. The public must wait longer for more vaccines to become available.

PRE

I

II

III

RR

IV

Best Case

  • Developer gets fast approval and has been concurrently manufacturing the vaccine during clinical trials.

  • The vaccine is now ready to distribute in mass quantities.

Inactivated Virus
Live Attenuated
Protein Subunit
DNA-Based
RNA-Based
Replicating Viral Vector
Non-Replicating Viral Vector
Virus-Like Particle
Other Vaccines
Vaccines In Use
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