Continuing a recent recovery, a key biotech ETF rose 0.9 percent Thursday, topping its key resistance level of $300 for the first time since January.

The iShares Nasdaq Biotechnology ETF (IBB) hit a high of $300.29 Thursday, and closed at $300.08, just below the $302.40 level hit in January. The previously elusive $300 mark has been a level of resistance for the ETF, which tested that level twice in August before trading lower.