Should e-cigarettes require clinical trials?

Manufacturers of e-cigarettes have received a warning from the FDA warning them about potential regulation of their e-cigarette devices. According to Fierce Drug Delivery, while many believe they are not, the FDA believes that e-cigarettes as a drug delivery device, and they should therefore have to go through clinical trials.

The FDA stated:

“FDA invites electronic cigarette firms to work in cooperation with the agency toward the goal of assuring that electronic cigarettes sold in the United States are lawfully marketed,” the letter to the association reads."

Do you agree? Should e-cigarettes be considered drug delivery devices and therefore be required to undergo clinical trials?