How Fast Can We Create a Covid-19 Vaccine?

12 to 18 months is the timeline we keep hearing about for a potential Covid-19 vaccine.

While this is possible, it would also be the fastest we've ever developed a vaccine.

Dr. Seema Yasmin takes a look at the standard timeline for creating a vaccine, from the exploratory stage all the way until manufacturing and quality control.

Just how does a Covid-19 vaccine fit into this timeline?

- To end the COVID-19pandemic and to returnto some kind of normal,we're gonna need a vaccine.But how long will it take to develop one?[upbeat keyboard music]12 to 18 months is the timelinethat we keep hearing aboutfor a potential COVID-19 vaccine.- When do we have a vaccine?12 to 18 months.- We're 12 to 18 monthsaway from this going away.- But here's a comparison.The fastest vaccine we'vepreviously developedwas for mumps and thattook four years to develop.And typically it takes 10 to15 years to develop a vaccine.So 12 to 18 months wouldbe record breaking.So let's look at how vaccines for virusesare typically developed.Stage one, the exploratory stage.The exploratory stage isalso known as the researchor discovery stage for a vaccine.Here researchers are trying to come upwith the best possible way toimmunize us against a virus.This first stage can takebetween two to four years.But right now scientists arespeeding through stage one,partly because of new technologies,and also because this SARS coronavirushas some similaritiesto the first SARS virus.Researchers are developingnucleotide-based vaccinesthat use the virus's genetic codeto potentially protect us from infection.This is a new way of developing a vaccine,where the virus's RNA orDNA prompts our bodiesto make a part of the virusand that's how we develop immunity to it.In January 2020, Chinese scientists sharedthe genetic sequenceof the new coronavirus.This allowed researchers around the worldto understand what the virus looked likeand how it worked, andit gave them a headstartto developing a vaccine.So if nucleotide-based vaccines work,that could mean that we're donewith this first exploratory stageand that cuts up to fouryears off our timeline.But, and this is a big but,nucleotide-based vaccineshave never made it throughclinical trials and FDA approval.So the exploratory stagecan take up to four years.But thanks to existingresearch and new technologiesfor vaccine development,some COVID-19 vaccinesmay already be through this stage.Stage two, preclinical stage.[upbeat keyboard music]This is where scientistsstart testing the vaccinein cell cultures and in animals to seeif it triggers an immune response.If there's no immuneresponse or the vaccineis causing harm to cells,then it's back to square one,the exploratory stage.So how quickly can we movethrough the pre-clinical stagefor a COVID-19 vaccine?Well, the reality is there'sno way to speed up this stage.And it'll probably take at least a year.But one way to make this more efficientis to start doing different stagesof vaccine development simultaneously.This is exactly what someCOVID-19 vaccine scientistsare doing right now.They're testing the vaccine in animalsat the same time that they'retesting the vaccine in humans.Doing the testing in animals and humansat the same time is unusual.But the FDA does have a fast-track processin cases of public health emergencies.Most vaccines don't make itpast the preclinical stage.But the American biotech company Modernais working on a COVID-19vaccine and was ableto get from the first exploratory stageto human trials in 63 days.Stage three: clinical trials.[upbeat keyboard music]This third stage is clinical trialsor testing the vaccine in people.Most vaccines don't everreach clinical trials.But if they do, then this stagecan take 19 months or moreand it consists of three phases.In the first phase, theexperimental vaccineis given to a small group of people.This phase can take about three months.If an experimental vaccine is safe,then it moves on to phase two.Phase two typically takes atleast six to eight months.During phase two, the vaccine is givento several hundred people,including a control groupwho get a placebo, not the actual vaccine.The control group helpsresearchers comparehow the vaccine works andcontrol for different variables.In phase three, thousands of people,usually folks in the outbreak area,will receive the experimental vaccine.This phase can also last at leastsix to eight months if not longer.And at this point, researchersare looking to make surethe vaccine is effective andto monitor any side effects.These are best-case scenarios in terms ofthe timeline for eachphase of human testing.Right now, there are atleast three COVID-19 vaccinesin phase-one clinical trials in the U.S.One way to speed upphase-three clinical trialsis to do something calleda human challenge trial.That's where people are given the vaccinebut then the scientistsintentionally infect themwith the virus to see more quicklyif the vaccine really works.It might sound like an extreme wayto speed up vaccine development,but it's been done many times before,including with cholera, dengue, and flu.Human challenge trials raisemany ethical red flags.In 2017, there was a proposedhuman challenge trialto speed up a Zikavaccine and Zika of coursecan cause severe birth defects.And that human challengetrial was criticizedby ethicists as being too risky.So, doing the math, the quickest waythat a COVID-19 vaccinecould make its way throughhuman testing without doinghuman challenge trialsis around 15 months.But there could be delays atany point along this timeline.Stage four, regulatory review.[upbeat keyboard music]At this stage, the vaccinemanufacturer submitsan application to receive a licenseso that they can manufacture the vaccine.Typically, it takes theFDA 10 months to conducta standard review, or sixmonths for a priority review.But the FDA can move fasterin case of a public health emergency.And some FDA programsallow for a rolling review.That's where the vaccinemaker is submittinginformation as they goalong instead of waiting'til they've finished and thensubmitting the application.The FDA is responsiblefor overseeing the safetyof any drug or vaccineavailable in the U.S.So, its review of this informationis absolutely critical before the vaccinecan make its way to a large population.No COVID-19 vaccines in theU.S. are near this stage.Over in the UK, scientistsat the University of Oxfordare hopeful that emergencyapproval of their vaccineby UK regulators could meanit's available in September.The best case would be a rolling reviewof a potential COVID-19vaccine taking less thanthe usual timeline of six to 10 months.Stage five: manufacturing.[upbeat keyboard music]This is the stage wheredrug companies start makingand distributing their vaccines.It takes an incredible amount of resourcesand investment ininfrastructure, raw materials,and scientific expertise.Manufacturing a vaccinecan take a long time.According to one estimate,it can take betweenseven to 36 months to produceand deliver a vaccine.It can also take a reallylong time for companiesto scale-up theirmanufacturing capabilities.The drug company Pfizertold The New York Timesthat it took them $600million and five yearsjust to produce a manufacturing plantfor one of their pneumococcal vaccines.And currently, we are notat the manufacturing stagefor a COVID-19 vaccine.But if we were, how quickly would we move?To be honest, this is an unknownand depends very much on the capacityof the drug company involved.Stage six: quality control.[upbeat keyboard music]So, we're not done yet.Once the vaccine isdistributed to the public,there's the ongoingstage of quality control.And this is done in the U.S. by the CDC,the FDA, and the vaccine maker.[upbeat keyboard music]So how long will it takebefore a vaccine isavailable for the public?Well, we can go through each stageand add up the time taken.But often these are time rangesand we're seeing right now that sometimesone stage is done at thesame time as another stage.When experts optimistically say that theyexpect a COVID-19 vaccineby the end of 2020,they're talking about anemergency use-authorized vaccine,not a fully approved one andvery limited supplies of one.Seeing a vaccine in 12 to 18 monthswould mean producing millions of dosesby January or June of 2021.If things continue to moveas quickly as they are now,there's a possibility that there could bea COVID-19 vaccine in twoyears, likely in early 2022.The major delays inpotentially seeing a vaccineby the new year would be the time it takesto safely move through clinical trialsand the manufacturing stage.Clinical trials usuallytake a minimum of 15 months.And that's if everything goes perfectlywith the vaccine workingexactly the way it was designedand not causing major side effects.The manufacturing stageis another unknown.Producing a safe and effective vaccinefor millions or billionsof people could take,at minimum, seven months.I know we're excited anddesperate for a vaccineto be available within 12 to 18 months.But what's even moreimportant than rushingis that we have a vaccine that's safeand a vaccine that works.And until then, we'regoing to have to stick withthe things that we know work,including those containment measuressuch as physical distancing.