Calling the tie "magic," Pfizer Inc. CEO Albert Bourla defended his firm's decision to spin off its Upjohn unit and merge in an all-stock deal with Mylan N.V., creating a new entity to be named later with pro forma revenues as high as $20 billion. "We have a commercial footprint that is very much focused on China, on emerging markets," he said, which will help Mylan.

Keeping with the trend of high-value biopharma deals, the second quarter of 2019 logged another eight partnerships worth $1 billion or more, with Gilead Sciences Inc. a party to three of them.