Still, Il Cavaliere may not be making a full comeback, as the head of the center-left Partito Democratico (PD) Pier Luigi Bersani is expected to take the elections.

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The experimental agent called nivolumab and Merck's drug, known as MK-3475, each work against a different mechanism called PD-1.

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The centre-left Democratic Party (PD) has just held a primary and confirmed Pier Luigi Bersani as its candidate.

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