This morning, Millennium Pharmaceuticals (NASDAQ:MLNM) reported second-quarter earnings. The market's reaction has been generally positive, with the stock up 4%. I'd agree that there are some bright spots, but I think the results are a bit mixed.

The company's shining star is definitely cancer drug Velcade for treating multiple myeloma. Velcade is doing well, with sales hitting $35 million in Q2. That's a robust 18% increase over the first quarter of this year. Management stuck with guidance for full-year sales of $140 million to $160 million, and I don't foresee any problems with the drug hitting that target.

The concern is Integrilin, which Millennium co-promotes with Schering-Plough (NYSE:SGP). Sales are declining, and Millennium does not believe it will hit its prior sales guidance. Millennium's revenue from Integrilin in Q2 was $48.7 million, which is down 8% from Q2 last year. However, it is possible that this trend could reverse. Millennium reached an agreement with GlaxoSmithKline (NYSE:GSK) to market Integrilin in Europe, and that could provide a boost to revenues. Also, Millennium is conducting additional trials with Integrilin that could expand the drug's use. I think it's prudent to take a wait-and-see approach with Integrilin, as I believe the growth prospects remain a big question mark.

With the shaky performance in Integrilin, Millennium is increasingly dependent on growth in Velcade to hit its goal of "non-GAAP profitability" by 2006. Maybe "real" profits will follow soon after, but those of us who recall statements about profitability by 2003/2004 are going to view this timeline with a bit of skepticism.

Growth in Velcade sales is going to be critical for reaching profitability. At this point, growth in multiple myeloma seems to be a given considering the fast uptake of the drug in that market. By itself, I'm not sure that market will be sufficient to hit the sales level that will be needed to make the company profitable.

Since Velcade is already approved for multiple myeloma, physicians can prescribe it "off label" for other cancers when they think it will benefit their patients. Such usage is likely going to depend on the generation of clinical data that suggests Velcade has a benefit. The most advanced clinical programs are in non-Hodgkin's lymphoma and non-small-cell lung cancer. Within the next six to nine months, the future plans for those two will be determined, and as the data becomes clearer in those diseases, off-label sales could pick up in advance of outright Food and Drug Administration approval.

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Fool contributor Charly Travers does not own shares of any company mentioned in this article.