After disappointing investors last year, biotechnology exchange traded funds (ETFs) are roaring back in significant fashion in 2017. For example, the iShares Nasdaq Biotechnology ETF (IBB), the largest biotechnology ETF by assets, is up 10.4% year-to-date. (See also: Charts Suggest 2017 Will Be the Year of Biotech.)

The SPDR S&P Biotech ETF (XBI), which equally weights its holdings, is higher by 16.1%, but even with those impressive performances, investors are treading lightly with biotech ETFs. Investors' skittishness pertaining to biotechnology ETFs comes after the group was drubbed in 2016 amid intense election year rhetoric aimed at higher drug prices.

President Donald Trump has levied his own harsh dose of rhetoric at pharmaceutical makers this year, but he has also said some encouraging things, words that can be viewed as catalysts for the rebounds being notched by IBB, XBI and other biotechnology ETFs.

Importantly for many of the companies that dwell in ETFs such as IBB and XBI, the Trump Administration is looking to streamline the Food & Drug Administration (FDA) approval process, potentially making it easier for companies to bring new products to market. As seasoned biotechnology investors know, there is nothing quite like a favorable FDA announcement to move a biotechnology stock.

“We're also going to be streamlining the process, so that from your standpoint, when you have a drug you can actually get it approved, instead of waiting for many, many years,” said Trump earlier this year. The new president is aiming to reduce FDA regulations by 75% to 80%.

Even amid that potentially favorable backdrop, investors are not flocking to biotechnology ETFs. For example, XBI has seen year-to-date inflows of just $20.5 million, not nearly enough to offset the almost $95 million pulled from the rival IBB. Making those data points all the more concerning is that investors are not outright dodging healthcare ETFs as highlighted by the more than $1.1 billion that has flowed into the Health Care Select Sector SPDR (XLV).

The market is not waiting for investors to renew their affinity for biotechnology ETFs. On Thursday, three biotechnology ETFs hit 52-week highs, including XBI. Several other biotechnology ETFs, including IBB, trade less than 3% below their 52-week highs and of the 215 ETFs up at least 10% year-to-date, at least seven are dedicated biotechnology funds.

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