The acquisition of Amplimmune Inc. adds a new set of immune checkpoint targets to MedImmune LLC's cancer portfolio, giving it more potential combinations to test in cancer.

The AstraZeneca plc unit now has four disclosed checkpoint inhibitors addressing four different targets. Although the programs are much earlier stage, that's the same number disclosed by Bristol-Myers Squibb Co., whose melanoma drug Yervoy ipilimumab was the first checkpoint inhibitor to reach the market (see "Dueling Checkpoint Pipelines").