BIIB Chart

What: Shares of the biotech giant Biogen (NASDAQ:BIIB) fell by more than 11% last month, according to data provided by S&P Global Market Intelligence. The drugmaker's monthly tumble was due to the downturn among all-things biotech, along with the domestic sales of its top-selling multiple sclerosis drug Tecfidera leveling off in recent quarters. 

So what: Biogen is one of the largest holdings of the iShares Nasdaq Biotechnology ETF (NASDAQ:IBB), making it a key name to watch in terms of the market's sentiment regarding biotechs at large. After all, Biogen's poor showing last month probably contributed significantly to the IBB's January blues:

IBB Chart

Now what: With Biogen's top-line expected to grow by a modest 6% this year, the market's focus is likely to turn toward the biotech's clinical activities moving forward. The good news is that Biogen is planning on plowing roughly 20% of its total revenues into R&D this year in hopes of kick-starting its growth engine. 

Among the biotech's more noteworthy clinical activities, Biogen and its partner Ionis Pharmaceuticals are reportedly making steady progress with their late-stage experimental treatment, nusinersen, for spinal muscular atrophy that might result in an accelerated regulatory filing sometime soon. Regardless, this collaboration should start to produce top-line data readouts in the first half of 2017, possibly leading to Biogen's next major new drug. 

Although Biogen probably won't turn in a great 2016 in terms of its share-price performance, I think the stock remains a compelling buy longer term because of the company's emerging clinical pipeline that sports potentially groundbreaking new drugs like aducanumab for Alzheimer's disease and, of course, nusinersen for spinal muscular atrophy.

George Budwell owns shares of iShares NASDAQ Biotechnology Index (ETF). The Motley Fool owns shares of and recommends Ionis Pharmaceuticals. The Motley Fool recommends Biogen. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.