Drug Development Process

The process of drug development 
Is something that’s quite relevant 
It has a lot of different steps
And it’s kind of long and complex

Preclinical studies are what happen first
So starting here let’s get immersed
Cell cultures or animals are used to check
If a drug seems safe and has the wanted effect

Then clinical studies, they come next
Four phases take place with human subjects

For Phase I the volunteers are healthy and strong
Twenty to a hundred of them for several months long
About two thirds of drugs make it to the next phase
Because these are the ones that seem to be safe

Phase II involves hundreds of folks with the target condition
Checking for effectiveness is the primary mission
It takes several months to two years to see
And only 45 percent of these drugs move on to Phase III

In Phase III it takes 1 to 4 years to collect data like a detective
Confirming if a drug is both safe and effective 
Hundreds to thousands of patients participate
But only five to ten percent of these drugs will graduate

Phase IV begins after a drug hits the market
To post-marketing surveillance we’ve gotta commit
Monitoring for rare adverse events in the population
To protect public health across the nation

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