
Two years ago, AbbVie (ABBV) paid a hefty $5.8 billion to buy a small company with an experimental treatment for small lung cancer, which accounts for up to 15 percent of all lung cancers. The move was a big bet to expand into oncology and lessen dependence on its Humira rheumatoid arthritis medication, an $18.4 billion seller last year that will soon face biosimilar competition.
Now, though, the premise appears to be souring.