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It's hard to find faults in Celgene's (CELG) second-quarter earnings numbers. Revenue was up 21% year over year and adjusted earnings jumped 17% compared to the year-ago quarter.

Celgene can't really have a good quarter without a strong performance from top-selling Revlimid since it makes up more than 60% of overall sales. Fortunately, sales of the cancer drug continue to grow -- up 18% year over year -- thanks to additional patients being prescribed Revlimid for new indications and patients staying on the drug for longer.

It was a mixed bag for Celgene's two other major cancer drugs. Pomalyst, which goes by Imnovid in some countries, continues its stellar uptake with sales increasing 35% year over year as patients stay on the cancer drug for more cycles. Abraxane, on the other hand, saw sales only increase 2%, although that's not surprising; sales were only up 1% year over year in the first quarter as the drug faces competition from newer drugs.

The standout for the newer drugs came from Otezla, which saw sales increase 170% year over year to reach $242 million, just shy of a blockbuster $1 billion run rate. Doctors continue to prescribe the oral drug before older biologic drugs that have to be injected or infused. Considering that only 10% of the drug's sales came from outside the U.S., there's still quite a bit of potential for higher growth left.

Adjusted earnings per share didn't grow quite as fast as revenue partially because of an increase in research and development expenses after adjusting for up-front expenses paid to collaborators for licensing deals. As long as those research expenses -- which include milestones and ongoing expenses paid to collaborators -- produces drugs down the line, the increased investment will be worth it.

Celgene still doesn't offer a dividend, but it is returning cash to shareholders through share repurchases. In the second quarter, the company bought back $343 million worth of its shares. Celgene still has $5.1 billion remaining under the stock repurchase program.

Looking forward

As it so often does, Celgene's sandbagging management increased its guidance midyear with Revlimid sales expected to come in $100 million higher at $6.8 billion and overall revenue to be at the top of the previous range of $10.75 billion to $11 billion. On the bottom line, 2016 adjusted earnings are expected to fall in the range of $5.70 to $5.75 per share, up from the previous guidance of $5.60 to $5.70.

Beyond the revenue and earnings in the second half of the year, investors can expect data from a trial testing GED-0301 in patients with Crohn's disease. It's only the first part of the trial, but it'll be a good test for GED-0301, which has blockbuster potential, especially if it works in other inflammatory diseases beyond Crohn's disease.