Biotech woes: Deja vu all over again

"It's been a tough month for biotech," Piper Jaffray analyst Josh Schimmer wrote in a research note. "Enough to make us wonder if there's something happening in our industry (concerns about pricing?) that's uniquely weighing on the sector."

With the selloff in biotech —Thursday entering its fourth day—setting the industry on edge, Schimmer's note could have been written Wednesday. But in fact it was published March 27, 2014, almost a year ago to the day.

For biotech watchers, as Yogi Berra would say, it's deja vu all over again. Through Wednesday, the Nasdaq Biotechnology Index dropped 6.9 percent since the close March 20. In that same period last year, the index dropped 7.2 percent. Panic ensued.

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Last year, there was a reason: Rep. Henry Waxman sent a letter dated March 20, 2014, to Gilead Sciences, questioning the pricing of its hepatitis C drug Sovaldi. The move crystallized fears in the drug industry around pushback on drug prices, and contributed to an overall decline in biotech stocks. From Feb. 25 to April 14 last year, the Nasdaq Biotech Index dropped 21 percent.

This year's string of declines is the longest since Feb. 4, during which time Gilead shocked the market with its announcement that it expected to provide an average discount of 46 percent on its hepatitis C drugs this year.

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This time, there's no such significant negative news peg driving the declines. They come after a euphoric day for biotech March 20, when Biogen reported positive data on an early-stage compound for Alzheimer's disease. Biogen's stock rose almost 10 percent for the day, on top of a gain into the data that altogether added about $29 billion in market value, according to Wells Fargo analyst Brian Abrahams. Abrahams, in a research note Thursday, questioned whether Biogen's shares got ahead of themselves.

Still, analysts expect Biogen's share price to increase 12 percent, according to an average of price targets on FactSet. For other large biotechs, the estimates are even higher: 18 percent for Gilead and Celgene. Analysts expect Amgen to gain 11 percent.

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So is this decline yet more of the same—a temporary pause in biotech's six-year climb?

"Almost like clockwork, the biotech tape began a meltdown yesterday, a little over 1 year since we went through this last time," Piper's Schimmer wrote in a note Thursday. "Obviously 2014 turned out to be a stellar year for biotech, and we believe industry fundamentals remain strong. 2015 should still be a good year for the industry, once we pass through this latest round of selling."