How are vaccines developed?
The effectiveness and life-saving nature of vaccines has led people to wonder when a coronavirus vaccine will be available. There are six stages of vaccine development: exploratory, pre-clinical, clinical development, regulatory review and approval, manufacturing, and quality control. The 5th stage, manufacturing, is when a vaccine becomes distributed, and it can take anywhere from a couple years to greater than 15 years for a vaccine to become available for widespread use.
With more than 100 coronavirus vaccines under development, researchers are reasonably confident that at least one will be successful. Federal health officials suggest a COVID-19 vaccine may be ready in a tenth of the time it usually takes. However, the requirement to scale up vaccine manufacturing for the numbers we would need within a short timeframe would be an extraordinary effort and will take global initiative.
Vaccine Development Process
Step 1: Research
In step 1, research is done to identify “natural or synthetic antigens that might help prevent or treat a disease.” An antigen is a foreign substance which induces an immune response in the body, particularly the production of antibodies. An antigen could include weakened strains of a virus.
Step 2: Preclinical
In step 2, researchers conduct testing to determine whether or not the candidate vaccines induce the desired immune response. Research is also done in this step to study the adverse effects that may occur, as well as formulation of a scalable, efficient, and reproducible manufacturing process. Many candidate vaccines do not make it past this step due to not producing immunity or proving harmful to test subjects.
Step 3: Clinical
In step 3, an application is submitted for an ‘Investigational New Drug’ to the U.S. Food and Drug Administration (FDA). The application includes information regarding the findings to date and how the drug will be tested, created, and distributed. Only after an approved application does the potential vaccine proceed through 3 phases of human testing. The FDA has 30 days to approve or deny the application. Phase 1 administers the candidate vaccine to a small group of people, less than 100, in a non-blinded study to determine whether it is safe to proceed and to learn about the responses it provokes among the volunteers. Phase 2 administers the vaccine candidate to a much larger group of people, usually hundreds, to study the safety, immunogenicity (ability to induce immune response), immunization schedule, and dose size. Phase 3 administers the vaccine candidate to an even larger group of people, usually thousands, in a randomized, placebo-controlled, blinded study. The same focus areas are being studied which includes monitoring potential side effects and determining the effectiveness. If the vaccine candidate successfully passes through all three stages of clinical study, regulatory review is initiated.
Step 4: Regulatory
In step 4, the vaccine developer submits a Biologics License Application to the FDA which then can conduct its own testing. The FDA monitors the potency, safety, and purity of the vaccine candidate and inspects the production process.
Step 5: Production
In step 5, manufacturing companies scale up production of large quantities of the vaccine implementing the necessary infrastructure, personnel, and equipment.
Step 6: Quality Control
In step 6, the vaccine has now been manufactured and widely distributed. Then starts the ongoing quality control process. The vaccine is continuously tracked and monitored for its safety and effectiveness through multiple systems including phase 4 trials (optional studies following release of vaccine) and two monitoring systems: the Vaccine Adverse Event Reporting System and the Vaccine Safety Datalink.
Coronavirus Vaccine Development
As of today, September 25, 2020, there are 52 candidate vaccines in step 2 – clinical study. 27 candidates are in phase 1 testing safety and dosage, 14 are in phase 2 expanded safety trials, and 11 are in phase 3 large scale efficacy tests. 5 candidate vaccines are currently approved for early or limited use. There are also 93 preclinical vaccine candidates under active investigation on animal subjects.
A number of companies, buoyed by Federal aid, have begun actually producing their candidate vaccines so that if and when they are approved past phase 3 trials they will be available to deploy immediately. This will hopefully speed up the availability of a meaningful vaccine.
If you have any questions about vaccine development, or concerns regarding the coming coronavirus vaccine, please contact us.