A team of researchers affiliated with several institutions in France has found evidence that suggests vaping can be used as a way to reduce cigarette smoking, but it can also lead to relapse. In their paper published in the Journal of the American Medical Association, the group describes their study involving thousands of volunteers over a nearly two-year period.
source https://www.lifetechnology.com/blogs/life-technology-news-blog/study-suggests-vaping-can-reduce-cigarette-smoking-but-also-leads-to-higher-relapse