I am not sure how long the process took for this particular vaccine but I have outlined below the procedure that is followed for EVERY vaccine...sorry it's loong!
For a vaccine to be approved:
Exploratory Stage
This stage involves basic laboratory research and often lasts 2-4 years.
Pre-Clinical Stage
Pre-clinical studies use tissue-culture or cell-culture systems and animal testing to assess the safety of the candidate vaccine and its immunogenicity, or ability to provoke an immune response. These studies give researchers an idea of the cellular responses they might expect in humans. They may also suggest a safe starting dose for the next phase of research as well as a safe method of administering the vaccine. This phase is variable but may be up to 5-8 years long but is more usually 2-3 years
Researchers may adapt the candidate vaccine during the pre-clinical state to try to make it more effective. They may also do challenge studies with the animals, meaning that they vaccinate the animals and then try to infect them with the target pathogen. Challenge studies are never conducted in humans.
Many candidate vaccines never progress beyond this stage because they fail to produce the desired immune response.
Application to trial on human subjects
A sponsor, usually a private company, submits an application The sponsor describes the manufacturing and testing processes, summarizes the laboratory reports, and describes the proposed study. An institutional review board, representing an institution where the clinical trial will be conducted, must approve the clinical protocol.
Once the application has been approved, the vaccine is subject to three phases of testing.
Next Steps: Clinical Studies with Human Subjects
Phase I Vaccine Trials
This first attempt to assess the candidate vaccine in humans involves a small group of adults, usually between 20-80 subjects. If the vaccine is intended for children, researchers will first test adults, and then gradually step down the age of the test subjects until they reach their target. Phase I trials may be non-blinded (also known as open-label in that the researchers and perhaps subjects know whether a vaccine or placebo is used).
The goals of Phase 1 testing are to assess the safety of the candidate vaccine and to determine the type and extent of immune response that the vaccine provokes. A promising Phase 1 trial will progress to the next stage.
Phase II Vaccine Trials
A larger group of several hundred individuals participates in Phase II testing. Some of the individuals may belong to groups at risk of acquiring the disease. These trials are randomized and well controlled, and include a placebo group.
The goals of Phase II testing are to study the candidate vaccine’s safety, immunogenicity, proposed doses, schedule of immunizations, and method of delivery.
Phase III Vaccine Trials
Successful Phase II candidate vaccines move on to larger trials, involving thousands to tens of thousands of people. These Phase III tests are randomized and double blind and involve the experimental vaccine being tested against a placebo (the placebo may be a saline solution, a vaccine for another disease, or some other substance).
One Phase III goal is to assess vaccine safety in a large group of people. Certain rare side effects might not surface in the smaller groups of subjects tested in earlier phases. For example, suppose that an adverse event related to a candidate vaccine might occur in 1 of every 10,000 people. To detect a significant difference for a low-frequency event, the trial would have to include 60,000 subjects, half of them in the control, or no vaccine, group
Vaccine efficacy is tested as well. These factors might include 1) Does the candidate vaccine prevent disease? 2) Does it prevent infection with the pathogen? 3) Does it lead to production of antibodies or other types of immune responses related to the pathogen?
Next Steps: Approval and Licensure
After a successful Phase III trial, the vaccine developer will submit a Application for licence to use.
After licensure, there is ongoing monitoring of the production of the vaccine, including inspecting facilities and reviewing the manufacturer’s tests of lots of vaccines for potency, safety and purity..
Post-Licensure Monitoring of Vaccines
A variety of systems monitor vaccines after they have been approved. They include Phase IV trials, the Vaccine Adverse Event Reporting System, and the Vaccine Safety Datalink.
Phase IV Trials
Phase IV trial are optional studies that drug companies may conduct after a vaccine is released. The manufacturer may continue to test the vaccine for safety, efficacy, and other potential uses.