That is a thing called a direct entry medical program. It gets you the the end of medical school in 6 years instead of 8 by dispensing with the undergraduate degree. The extra two years cover the sciences and how to learn at medical school speeds.

It shaves two years off, but at the cost of pinning the student into a rigid track. The number of high school seniors who think they want to be doctors and change their mind during an undergraduate is pretty high.