We waited 50 years for this? Human Genome Sciences (Nasdaq: HGSI) gained approval of the first drug developed for lupus in half a century, but in its first full quarter on the market Benlysta brought in an uninspiring $7.8 million.

Another $1.2 million has been shipped out but not yet recognized as revenue, but still, $9 million is a far cry from a $250 million quarter that would make the drug a blockbuster. Given the unmet need, Benlysta was supposed to blow past that arbitrary number.

That's the bad news. Fortunately, it gets a little better.

Human Genome Sciences broke out the shipping of Benlysta by months, and there was a clear acceleration for the drug. The company shipped out more than $4 million in June, compared to just more than $1 million in the first month.

The somewhat slow uptake is to be expected considering that the clinical trial results weren't a home run. "Better than nothing" is good enough to get on the market, but it's a marginal marketing plan.

Fortunately, doctors seem open to trying it. Management said 85% to 90% of rheumatologists have told the company they intend to use Benlysta eventually. As doctors gain experience with the medication, they'll be more likely to increase their prescription habits. Benlysta is in somewhat the same predicament as AVANIR Pharmaceuticals' (Nasdaq: AVNR) Nuedexta. The wait-and-see approach takes time to develop.

There's also potential to increase sales by expanding beyond the U.S. The drug was approved by regulatory authorities in Europe and Canada this month. Those markets aren't as large as the U.S., but it's an incremental benefit for Human Genome Sciences and marketing partner GlaxoSmithKline (NYSE: GSK).

Human Genome Sciences' investors should sit tight. As they say, it's not how you start, it's how you finish.

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