Yesterday, drug developer and Rule Breakers pick PDL BioPharma (NASDAQ:PDLI) released its first-quarter financial results.

For the quarter, revenue was up 18% year over year, as sales of PDL's own marketed products gained 31%, and the royalties PDL receives for drugs like MedImmune's (NASDAQ:MEDI) Synagis moved 11% higher. PDL lost $0.09 a share on the quarter, burning through a modest $9 million in cash in operating activities.

It's worth mentioning that there is some seasonality to when PDL receives some of its royalty payments, so investors shouldn't extrapolate one bad or good quarter as indicative of some dramatic change in its operations. For the full year, PDL expects non-GAAP earnings per share to be in the $0.50 range.

PDL's top-line growth is nice to see, but advances in its clinical stage drug pipeline will be most important to the drug developer's financial future. PDL has announced that it was advancing lead compound Nuvion into phase 3 trials and that the potential multiple sclerosis therapy daclizumab, which is partnered with Biogen Idec (NASDAQ:BIIB), was continuing in late-stage development. But it has been a long while since investors have gotten any hard data from any of its top compounds to bite into and chew on.

After numerous drug development delays, it's time PDL shows investors some data, so that they aren't hanging onto shares based solely on the promises and dreams of PDL's management. Thankfully, in three weeks, PDL will present more Nuvion data at the Digestive Disease Week meeting. This should give investors a better idea of the drug's progress and potential.

Earlier in the quarter, PDL came under attack from an activist investor for questionable expense control and a lack of progress with its drug pipeline. On the quarterly conference call, it was apparent that PDL's management is now at least trying harder to explain its spending habits -- like the expensive move of its headquarters -- and acknowledging that there are steps it can take to move some of its compounds along at a faster rate. For the sake of PDL investors, let's hope management delivers on some of these programs sooner rather than later.

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Fool contributor Brian Lawler does not own shares of any company mentioned in this article. Biogen Idec is a Stock Advisor recommendation. The Fool has a disclosure policy.