Celgene's (NASDAQ:CELG) Vidaza, which began facing U.S. generic competition in September of 2013, just can't seem to catch a break.

First there was the generic competition -- which dropped sales by 27% year-over-year last quarter to $148 million. And more recently the drug failed a phase 3 trial in elderly patients with newly-diagnosed acute myeloid leukemia. The drug failed to provide a statistically significant benefit to median overall survival.

So, should this drug's failure dramatically affect the Celgene investing thesis?

In the video below, from Market Checkup, the Motley Fool's health care-focused investing show, health care analysts Michael Douglass and David Williamson answer.