What: Shares of Alnylam Pharmaceuticals (ALNY -0.52%) were trading nearly 10% lower at 10:00 a.m. Monday after the company presented updated clinical data on two of its investigational compounds at the ongoing American Society of Hematology meeting.

So what: On Sunday the company gave an update on its ongoing Phase 1/2 trial of ALN-CC5, a compound being tested as a potential treatment for Paroxysmal Nocturnal Hemoglobinuria, or PNH. The results of the trial showed that ALN-CC5 achieved up to a 99% knockdown of Serum C5 levels and up to a 98% inhibition of Serum Hemolytic activity.

Those results managed to meet the company's goal of an 80% reduction in serum hemolytic activity and Alnylam management team believes that ALN-CC5 showed enough durability to possibly support a monthly, or even quarterly, dose regimen. The company will be transitioning the study to include patients with PNH by the end of this year and it plans on providing updated clinical data from this study by mid-2016.

In a second release Alnylam provided a clinical update on ALN-AT3, its potential treatment for Hemophilia. ALN-AT3 has officially been renamed Fitusiran and in its ongoing phase 1 clinical study was able to lower antithrombin activity by up to 88%, which in turn reduced annualized bleeding rates in patients by 85%. Fitusiran was also well tolerated in patients with no serious adverse events reported. Alnylam confirmed that Fitusiran is still on track to initiate phase 3 studies by the middle of next year.

On Dec. 10 Alnylam will be hosting a research and development day that should give its investors more color on the progress that is being made in the company's vast pipeline.

Now what: Overall the clinical data looked good so I'm a bit puzzled why shares are trading lower on Monday. Its possible that the stock is simply selling off because the biotech sector in general is under pressure today. The First Trust NYSE Arca Biotech ETF (FBT 0.11%), an exchange traded fund that invests in an assortment of biotech stocks is also trading much lower today.

Alnylam is still in money-losing mode so its stock is likely to remain subject to the whims of more speculative biotech investors until it shows that it can generate a profit from operations. Until that happens long-term investors should ignore short-term price movements and keep their eyes focused on the clinical data. If Alnylam continues to report good results then the share price will take care of itself.