Endocyte (NASDAQ:ECYT) shares got hammered today on the disappointing news that partner Merck (NYSE:MRK) decided to hand back rights to vintafolide and leave the company to go it alone.

Endocyte is waiting for more data from a phase 2b trial in non-small cell lung cancer before deciding what vintafolide's future should be. The drug recently flopped in a phase 3 trial for platinum-resistant ovarian cancer.

So, with a lot of optimism priced out of the stock, is this a buying opportunity?

In the video below, health care analysts Michael Douglass and David Williamson let you know what they think.

David Williamson owns shares of Merck. Michael Douglass has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not 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.