Pfizer-Allergan merger scrapped

Pharmaceutical giant Pfizer's $160 billion merger with fellow drug giant Allergan has been scrapped.

In the mutually agreed upon cancellation, Pfizer will pay Allergan $150 million in breakup fees.

The news comes just days after the Obama administration revealed new rules designed to undercut tax inversion deals where U.S. firms seek to merge with companies in lower-tax nations and then move their headquarters.

Read more from USA Today.