Related: Biotech ETFs Remain Bell of the Ball

XBI is an equal-weight ETF, so it is not dominated by one or two large-cap stocks, but its two largest holdings are Kite Pharma and June Therapeutics.

ETF traders who are betting big on the biotechnology sector rebound have also utilized leveraged long options including the Direxion Daily S&P Biotech Bull Shares (NYSEArca: LABU), which takes the 3x or 300% daily performance of the S&P Biotechnology Select Industry Index. That is the same index XBI tracks.

Other options include the ProShares UltraPro Nasdaq Biotechnology (NasdaqGM: UBIO), which takes the 3x daily performance of the Nasdaq Biotechnology Index, and the ProShares Ultra Nasdaq Biotechnology (NasdaqGM: BIB), which takes the 2x performance of the same benchmark.

For more information on the biotech sector, visit our biotechnology category.