Human Genome Sciences (Nasdaq: HGSI) says, "We don't think the Food and Drug Administration is going to approve our new hepatitis C drug, Zalbin."

Investors reply, "Tell us something we didn't already know."

After making the above comment this morning, shares are trading up slightly, just like the rest of the market.

The theory behind Zalbin was a good one. Current hepatitis C treatments from Roche and Merck (NYSE: MRK) can cause severe side effects in many patients. The side effects can be so bad that people are advised to take the once-weekly injection at the beginning of the weekend, so they'll still be able to work during the nearly year-long treatment regimen. Zalbin attempted to make the side effects a little less burdensome with an every-other-week injection cycle.

But Zalbin's efficacy data wasn't really as strong as the current treatments, and the FDA thinks the risk-benefit analysis isn't tipping quite enough toward benefit to approve the drug. The FDA is still reviewing Zalbin, but early communication from the agency led Human Genome to think the FDA isn't going to approve it.

In April, Human Genome's marketing partner, Novartis (NYSE: NVS), pulled its marketing application in Europe, after it was clear that regulators there weren't going to approve the drug.

Of course, even if the FDA did approve Zalbin, it was likely to be a marketing flop. Next-generation drugs from Merck and Vertex Pharmaceuticals (Nasdaq: VRTX) are being tested in combination with the current treatments. The combination treatments will likely become the standard of care, which would leave Zalbin on the sidelines until Human Genome could prove that it worked as well in combination.

Now that Zalbin is all but dead -- Novartis and Human Genome are considering testing the drug as a once-a-month treatment, but I wouldn't hold my breath -- investors can turn their eyes to Human Genome's real future: lupus treatment Benlysta. Human Genome and marketing partner GlaxoSmithKline (NYSE: GSK) submitted applications in the U.S. and Europe this month, so a decision could come by the end of the year.

Expectations for Benlysta's approval are orders of magnitude higher than they were for Zalbin, so don't expect the same kind of shrug if regulators give any hint that they might not approve Benlysta.

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Fool contributor Brian Orelli, Ph.D., doesn't own shares of any company mentioned in this article. Novartis is a Global Gains pick. The Fool owns shares of GlaxoSmithKline and has a disclosure policy.