In this segment from Tuesday's Market Checkup, Motley Fool health-care analysts David Williamson and Michael Douglass look at Merck (NYSE:MRK), and why its pipeline is one investors should be excited about today.

Amazingly, Merck looks as though it will be the first to market with its PD1 immuno-oncology drug 3475, beating the seeming favorite Bristol-Myers Squibb's (NYSE:BMY)nivolumab. David tells investors why he's excited about this coming megablockbuster and its potential for off-label use, as well as which key trials for the drug investors will want to watch for this year.

David Williamson owns shares of Merck. Michael Douglass and The Motley Fool have no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.