The majority of attention focused by investors on Gilead Sciences (GILD -0.74%) is related to its top-selling hepatitis C drugs. While those treatments generate more than $19 billion in annual revenue for the company, their sales have slowed amid growing competition. However, avoiding Gilead Sciences based on that may cost you a chance to profit.

In this clip from The Motley Fool's Industry Focus: Healthcare podcast, analyst Kristine Harjes and contributor Todd Campbell discuss why investors might want to look beyond the company's short-term sales slowdown and add shares for the long haul.

A transcript follows the video.

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This podcast was recorded on Jul. 1, 2016. 

Kristine Harjes: You mentioned that we've seen a little bit of a slowdown in hepatitis C, and because of that, this stock is so cheap. I mean, really, the market, I think, is tremendously under-appreciating Gilead Sciences. The headline story right now is: "Oh, no, Harvoni sales have fallen 50% year-over-year in the U.S." I just am not that concerned about it. I mean, you've got Epclusa coming in now, but even more importantly, there is so much more to this company than just hepatitis C.

Todd Campbell: Oh, yeah! I mean, they've got drugs in belt now for NASH that theoretically could be billion-dollar blockbusters if they pan out. They've also got a very intriguing deal with Galapagos (NASDAQ: GLPG) on a late-stage drug that could target autoimmune diseases, which would be potentially huge. I mean, remember that autoimmune diseases -- that market supports Humira, which is a $14 billion a year drug. Yeah, they have revenue drivers that I think are not being appropriately modeled in by investors right now. I think investors are focusing too much on the flat-lining of sales for hepatitis C. In my view, the launch of this drug actually not only solidifies the market share, but could offer upside to the second half of this year, that's not baked into a lot of people's models.

Harjes: If you're curious about the ratio, they're trading at under 7x trailing earnings. That is insane!

Campbell: Yeah. I mean, that makes them, by far, the cheapest buy of big cap biotechs. I think that if you're going to rank the three stocks that we talked about today, Gilead Sciences, then Celgene, then Biogen.

Harjes: I completely agree, and I'll just add one more part to the Gilead story, is that they're sitting on $21 billion in cash on the balance sheet, and they are historically really, really smart about acquisitions. They're taking their time, they're being very patient with it, they're using a lot of the money to buy back their own shares, because hey, they're really cheap. But I would anticipate some interesting acquisitions going forward, that could be total game changers in any of the different disease areas that we've listed, or a completely new one. Who knows? This is a company that I am really excited about, if you can't hear it in my voice. I think Todd, you are too.

Campbell: Yeah. I mean, I always like good management teams, right? Proven management teams. They've been there, they've done that, and they've proven that they know how to protect portfolios and develop new drugs. Gilead has definitely done that, Celgene has definitely done that.